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In Reply to: RE: Have to take the Lamm M1.1 off my list posted by A.Wayne on December 01, 2014 at 10:46:43
What you are saying is all nice but not really true. THe LAMM has more than enough current grunt to drive Apogee Scintillas so the Thiel is not really a huge challenge. Your explanation for "lack of life" also doesn't hold water because one of the very best sounding amps we have heard on the Thiels was the VAC 30/30, which I am sure would not meet your definition of sufficient drive for the Thiel. Also, my friend's standard amps, Octave MRE 280 monoblocks, would also not deliver the same amount of current as the LAMMs into the Thiels more diffcult load and yet it sounds significantly better.
Also, up until clipping the KR VA350i also drove the Thiels beautifully.
Given that the LAMMs in this case were purchased SPECIFICALLY to drive 1 ohm Scintillas and do so without complaint and without clipping in a largish room to highish volumes (when set to the 1-6 ohm setting) I am not quite sure how you arrived at the conclusion (they make 230watts into 2 ohms...hardly wimpy). Given that the Thiel is 90db or so per watt it doesn't take a lot of power to get pretty loud. If 230 watts into 2 ohms, which in my book is indication of sufficient current from this amp, is not sufficient to drive a 90+db speaker to loud levels in a moderate sized room then please educate me with some math on how much power I should need??
Nevermind I will do it for you.
Let's say the Thiel is 90db watt but it is 4 ohm so it takes actually 2 watts to reach that volume. Now add a second speaker and give us 3db more for that and then subtract about 3 db for losses to the listening position (it is less than the square of the distance because of reflections) and we get 90db for 2 watts at the listenign position of about 3 to 3.5 meters away (already pretty loud).
90db 2 watts
93db 4 watts
96db 8 watts
99db 16 watts
102db 32 watts
105db 64 watts
108db 128 watts
So, we see that we should be able to get well over 100db at the listening position from this amp...too loud to listen to for a long time. Even with compression setting in we would be well over 100db with the power available. Also, give that the power, while not doubling into 2 ohms, is still 230 watts, indicating plenty of current drive from the amp.
As for the other Apogees we were using, the Studio Grand is a nice and easy 5 ohm load with about 87db/watt sensitivity and the Centaur Major is something similar. You can tell me that an amp of the LAMMs capabilities cannot drive these speakers successfully?? You must be joking I think. We have driven them with a number of tube amps as well as lesser SS amps (and more beastly ones too) and never encountered an amp that "could not drive" these more modest load Apogees.
Follow Ups:
That would all be true if the speaker in question were a Resistor.
The fact that the Thiel is a fairly reactive load cuts DELIVERED power. At the Cosine of the phase angle between voltage and current.
Too much is never enough
Are you nuts picture guy, who's going to explain that to them ... :)
Yes, I'm nuts. Does that make the truth easier to take?Didn't think so.
The short of it.
Speakers are NOT resistive, as a general rule. They range from slightly capactive or inductive to fairly large extremes of 'reactance'. Large phase angles at the same place as large impedance dips are deadly to any but the more robust amp designs.
Power amps with the SAME RMS power, as measured into a resistor, vary WIDELY in their ability to drive reactive loads. The greater the difference between voltage and current peaks, the WORSE it is.
When voltage and current are 90 degrees apart, NO power is delivered to the load. I've never even heard of this in a loudspeaker. I don't think this is possible in a sound transducer.
What we're talking about here is called 'Power Factor'. Here is the WIKI link which will explain it in general terms. Europe, for example has strict rules on power factor, especially for all those millions of wall warts powering or charging cellphones to lap tops. If you owned a factory, you could be charged a PREMIUM on your electric bill for large power factor usage. You USE VA but get billed for WATTS. Same on your stereo. Speakers use VA, but the amp produces Watts, which are basically from a resistive measure.
PF=1 is pure resistive.
Too much is never enough
Edits: 12/03/14
He said the Vac 30/CH sounded better so power factor doesn't seem to be the issue then right? I get it about measurements in to a purely resistive load too.
E
T
Edits: 12/05/14 12/05/14
You've got a point. And, at THIS point, I'll bow out. I have no idea why the amp in question didn't sound rite. I think the 'voicing with particular speakers' arguement may be a red herring, since all speakers, even within a manufacturers line are subtly or greatly different. Which speaker do you pick as your 'reference' for your new amp? A bewildering choice.
PF was a suggestion, but I'm not 'married' to it. Maybe someone has the right idea?
Too much is never enough
To be honest I am a bit mystified by it as well. IMO, the amps have plenty of grunt, Mr. A.Wayne's objections notwithstanding, and the measurements reveal that they have some highly desirable characteristics such as low feedback, flat distortion vs. frequency, a benign harmonic distortion pattern and IMD pattern is not particularly nasty.
However, I had a similar experience with the Einstein "The Absolute Tune" that I once owned. It had measurements not so dissimilar to the LAMM but with significantly less power. It did not sound bad, but it was disappointing overall in terms of dynamics and tone. Clearly I have more work to do on my metrics for good sound :), although to be fair, once I really ran the numbers it did not fair all that well against amps like the Wyetech Topaz...on paper and now I am quite sure in real life it would get stomped by the Wyetech.
Lamm ,Notice curve and power outputs 8,4,2... Distortion lowers with a sweet spot between 1-10watts. If Mr Cab measured while listening he will find the amp sweet spot is about here, the transition after the knee is the same up to a 100 watts,( @ .1% thd the power is the same in all impedance's) before the last big swing towards 1% thd.
Cab listen again , keep the Lamm below 30 watts on a high sensitivity speaker and report ...
regards
Edits: 12/05/14 12/05/14 12/05/14 12/05/14
Cab listen again , keep the Lamm below 30 watts on a high sensitivity speaker and report ..."
You still don't get it, do you?? MOST of the listening was well below 30 watts. Only peaks would be higher than this...even with the Apogees.
You know this because you measured right , get a clue Cab , if all you have is , continuos conjecture and dogma then no one will take you serious, well i wont .
Merry xmas
I know this because I know how loud we listen and how much power that takes...we do measure SPL levels and this is then easy to calculate power to a reasonable accuracy.
You are one of those guys who justifies needing 1000 watts becuase for 5ms there is a peak in a recording when the other 99.999% of the recording uses a watt of power or less for a normal listening level.
Cab,
Did you level match when comparing , what did you compare the Lamm to on the scinnies ? Best to measure listening voltage , this would really give us something to use along with your opinion , seeing we are not there to hear for ourselves..
Regards ...
In these cases I did not level match. However, if you read my old reviews on preamps I was level matching to within 0.5db.
Do YOU do everything you are recommending? I seriously doubt it. I think hypocrisy would be the key word here. We were listening for pleasure not trying to dissect the amp.
I really don't care if you use my opinion or not...you don't seem to get that. I KNOW how to make measurements (see my review on the Piega C2 ltd. as an example in Positive Feedback). I know how to measure the SPL level I listen at and I know how that translates to power.
So, when I tell you we were rarely above 30watts I know what I am talking about.
In the end, all you can do is listen for yourself. I merely stated I will take it off MY list of desirable amps...YMMV.
Cab ,Im not saying you are Full , i don't have to , you're doing a good job of it, unfortunately for you i have experience working with scinnies , ribbons in general and loudspeakers on a whole ( past design work ) , here's Audio Mag take on the scinnies, mirrors mine..
"However, this gorgeous sound comes at a price. Presented with the Scintilla's 1-ohm load, distinctly outside manufacturers' ratings, a number of fine amps took on unpredictable sonic characteristics. Greenhill's reference Levinson ML-9 stereo amplifier which usually plays with a neutral midrange and a big, dynamic bass-became sweeter, tube-like, and mellow (not unwelcome, by the way!) until its current limiting cut in (at clipping) with a spray of static. The dual-mono Tandberg 3009As, which Greenhill had found to be fast, detailed amps with etched highs, took on a bass emphasis and acquired a stronger midrange presence. Both amps can deliver more than 400 watts into 4 ohms, and Tandberg claims more than 800 watts output at 1 ohm. But neither could drive the Scintillas on peaks to more than 88 dB (at 1 meter) in Kachalsky's normally upholstered living room.
The speakers were then reconfigured to a 4-ohm load. Seven color-coded wires were repositioned on the rear of the speaker terminals and on a separate terminal strip within the enclosure. This 30-minute procedure must be done carefully for each speaker, since the hardware can easily slip down into the nylon sock that covers the rear of the enclosure. It also helps to have good color vision (both authors are colorblind, so we acknowledge the help of Mrs. Kachalsky) to place the purple, green, and gray wires on the correct terminals. At 4 ohms, the authors heard no sonic aberrations in the amplifiers, but the Scintillas lacked the ultimate naturalness, air, openness, and midrange clarity heard with the 1ohm configuration. You won't realize this unless you have heard them driven at the lower impedance setting.
We preferred the very expensive Krell mono KMA-100 ($4,900/pair) and 200watt KMA-200 ($7,500/pair) amplifiers for driving the Scintillas. We used them in a bi-amplified fashion (a pair of KMA-100s for midrange and tweeter, a pair of KMA-200s for the woofers), which produced the widest dynamic range. At 1 ohm, the KMA-100 is claimed to deliver 800 watts per channel and the KMA-200 puts out 1,600 watts per channel. A single pair of Krells were "bi-wired" (two speaker cables connected to each amplifier output terminal) to each Scintilla's double set of speaker posts: SPL measurements showed Scintilla output peaks of 94 dB (KMA-100s) and 98 dB (KMA-200s) at audible clipping. No change in tonal character or sudden presence effects were heard at 1 ohm-just sweet, open, detailed sound. Dan D'Agostino, the Krells' designer, uses the Apogees as a test load. The Class� Audio DR-3 amp also performs beautifully at the low-impedance setting."
-Audio 1985
So i will iterate , the Lamm is not the amp for that job there is no way to listen to scinnies or any low sensitivity low -z ribbon with less than 400-800 watts /ch, to do so will net a lame soft sound , devoid of dynamics and realism of size. To do with 30 watts would mean a listening level din of 72- 74db with dynamic peaks not exceeding 10db, far below the levels necessary for realism of sound ..Since you did not measure nor able to say more than this amp is off "my list" i would have to assume you have an agenda , sadly audio today is cluttered with nothing more than opinionated rags and "reviewers "
Regards
Edits: 12/08/14 12/08/14
"M1.2's output varies with output power with the Hi-Z bias setting into loads varying from 2 to 16 ohms. The amplifier comfortably exceeds its rated output power, giving out 180W into 8 ohms (22.6dBW), 305W into 4 ohms (21.8dBW), and 490W into 2 ohms (20.9dBW), all at 1% THD."
Now, on what planet is that an incapable amplifier? The M1.1 gives similiar numbers but was not tested in the same way as the M1.2 (TJN only tested the low impedance on the low impedance settings). Therefore, I give you the M1.2 numbers.
"For comparison, fig.5 shows what happens with Lo-Z output-stage biasing: the maximum output power is almost halved, but the signal benefits from significantly lower distortion into low impedances. "
Yes, power is halved but the amount of Class A into the lower loads is increased. STill it delivers over 200 watts into 2 ohms. What isn't tested is power at 1 ohm but LAMM itself states that in the LowZ mode it will produce 400watts into 1 ohm...more than enough to give Scintillas a kick. Given that a Krell KMA 100 can generate 94db and also makes around 400 watts into 1 ohm I would says that the LAMM can do similar.
Regardless, the sound from the Thiels, a MUCH easier drive than Scintillas and much higher sensitivity also did not sound as good as expected...when I said not more than 30 watts I was referring to Thiels, not Scintillas...I know you like to forget but I will remind you one last time I am talking about FOUR different loudspeakers...not just Scintillas.
"My B-weighted estimate on its tweeter axis, assessed with DRA Labs' MLSSA system, was slightly above that figure, at 90.7dB(B)/2.83V/m."
So they are 90db/3 ohm speakers:
Let's say it takes 2.5 watts to make 90db from ONE speaker...two = 93db. Drop in room of about the same gives 90db at the listening position for 2.5 watts:
90db = 2.5 watts
93db = 5 watts
96db = 10 watts
99db = 20 watts
102db = 40 watts
Now, I can tell you for certain that we were not listening with peaks above 99db...this is too loud for my comfort. Average levels were in the low to mid 80s with peaks in the mid-90s, therefore, I can state that we were almost certainly using less than 30 watts.
So, to reiterate, there is plenty of Juice from the LAMMS and stereophile's measurements bear that out for all kinds of speakers...IMO it just doesn't sound as good as one would hope for that kind of money. If you think it does then more power to you.
"i would have to assume you have an agenda "
Based on what deduction have your reached this odd conclusion?? That I didn't like the sound of the amp? Is that now grounds for "agendas"?? Seriously??
In case you haven't noticed, rags are not big on negative comments like I have given...so your point is simply wrong.
Mr Morricab wrote:"B-weighted estimate on its tweeter axis, assessed with DRA Labs' MLSSA system, was slightly above that figure, at 90.7dB(B)/2.83V/m."
So they are 90db/3 ohm speakers:
Let's say it takes 2.5 watts to make 90db from ONE speaker...two = 93db. Drop in room of about the same gives 90db at the listening position for 2.5 watts:
90db = 2.5 watts
93db = 5 watts
96db = 10 watts
99db = 20 watts
102db = 40 watts"
Mr Cab are you sure you are a scientist or an Attorney ..? you only lose 3 DB at 3-4 M listening distance? you should check out the 3.7's impedance phase angles too and to answer your other point, you were the one who brought up scinnies, by stating this was a high current amp bought for scinnies.
Regards
Edits: 12/09/14 12/09/14 12/09/14
Cab,
You are entitled to your own opinion , not your own science...
"The dual-mono Tandberg 3009As, which Greenhill had found to be fast, detailed amps with etched highs, took on a bass emphasis and acquired a stronger midrange presence. Both amps can deliver more than 400 watts into 4 ohms, and Tandberg claims more than 800 watts output at 1 ohm. But neither could drive the Scintillas on peaks to more than 88 dB (at 1 meter) in Kachalsky's normally upholstered living room."
MEASURED:
So 800 watts peak at 1 ohm netted 88db (measured @1M) and you estimate what ? As to your other conjecture of the where lamm 1.1 would put out 400 + watts at 1 ohm is also absurd, I had gone to the trouble to post up it's thd vs power output and at anything above 100 watts it's distortion takes off , same for 8,4,2. I'm sorry Cab, you may not be as scientific as you project, Give us your opinion, I'm usually in agreement, but until you improve on your methodology, stay away from such absurd statements as fact.
My take ? if you have ribbons or hard to drive heavy current demanding speakers, stay away from Lamm 1.1 . Acceptable to me after viewing the 1.1 test results ...
Regards..
And I have seen much higher outputs mentioned in other reviews for more modest 1 ohm outputs. Seriously, something is off with the numbers you have presented. 88db with 800watts??? Surely you're joking Mr. A.Wayne.
Either their Scintillas were broken or the Tandberg amps make nowhere near the claimed 800 watts into 1 ohm...wouldn't be the first time someone lied about their output.
800 watts and 88db implies sensitivity below 70db and that is simply not the facts.
79 = 1 watt (1 ohm)
82 = 2 watts
85 = 4 watts
88 = 8 watts
so 8 watts not 800 watts!
Mr Morricab,
Read again , slowly, that was an actually test done by a mag reviewer , not some opinionated peristalsis from a golden Ear wanton... :)
Sensitivity below 74 db is believable , you should measure Cab and stop trying to bluff your way thru everything. I'm solidly of the opinion, you were never really exposed to SOTA level hi-fi based on your Comments or do you think everyone powering these things with mega watts were just insane , including Jason Bloom.
8 watts .. LOL , 2,83v on a scinnie is 8 watts, go measure ....
Regards
In 1ohm mode, the conventionally rated voltage sensitivity (referred to 2.83V input, an 8ohm 'watt') will increase by 6dB, bringing the apparent in-room sensitivity to 85dB/W. Given sufficient current, this would explain why the Krells could attain such high sound levels with the Scintillas. In a medium-sized (80m3) room, peak levels of 103-105dBA will be possible from a stereo pair, this a decently high level if not quite of disco intensity. Driven to this level, they could be clearly heard all over the house, even with the intervening doors closed.
This is from Martin Colloms in Hifi News in 1985.
Krell KSA-100 is the obvious choice, capable of driving the Scintilla to majestic levels in 1 ohm mode. In truth, one would need to go no further.
Also from the same review. Now the KSA100 makes 800 watts into 1 ohm or about double what the Lamms can do. That is only 3db less so it means that the Lamms can do around 100db before clipping.
Clearly the Tandbergs were not up to what they claimed.
I would also like to address your theoretical 3 db ,less say for discussion sakes you are running around 20 watts for your avg din of 84 db from listening position, a dynamic peak of 15 db will require 640 watts, clearly exceeding the 400 @3%thd clipping out of your Lamm 1.1 . Less say your super scinnies only need 10 watts to achieve 84db from your listening position, then you will still require 320 watts to reproduce the same dynamic peak , at which time the Lamm is producing above 2% thd and clipping, hence my point.
So less say you like to listen at even lower levels and size and drop your avg din to 81 db max then you will require 160 watts of power to reproduced sustained peak of 15 db , at which time your lamm would be putting out 170 watts at approx 1% thd @ 1 ohm( clipping ). Hence my point , you dislike the sound of the lamm over driven ..
Note: that anything above 100 watts is after the knee and thd is a straight line up ..SO ,
You are dynamic limited with this amplfier , IMO, it's best suited for 4 ohm and above speakers in the 88db/w/m and above range..
Regards,
Edits: 12/17/14
" The M1.1's discrete clipping powers (at 1% THD+N) were 140W into 8 ohms (21.5dBW) (115V line); 138W into 4 ohms (18.4dBW) (114V line); and 230W into 2 ohms (17.6dBW) (115V line). "
The Lamm puts out 230 watts into 2 ohms at 1% and around 400 into 1 ohm.
That is in the low impedance mode.
The M1.2 was more thoroughly tested in the high impedance mode and records the following:
" Fig.4 shows how the THD+noise percentage present in the M1.2's output varies with output power with the Hi-Z bias setting into loads varying from 2 to 16 ohms. The amplifier comfortably exceeds its rated output power, giving out 180W into 8 ohms (22.6dBW), 305W into 4 ohms (21.8dBW), and 490W into 2 ohms (20.9dBW), all at 1% THD. "
So, in the high Z setting it makes nearly 500 watts into 2 ohms and half that at the low Z mode (so about the same as the M1.1) and doubles again into 1 ohm.
That is a LOT more power than you are claiming. Not 5%, not 3% but 1% THD.
"The M1.2 Reference is conservatively rated to deliver 110 Watts into 8 and 4 Ohms in pure class A operation (high and low impedance settings, respectively); 220 Watts into 2 Ohms, and 400 Watts into 1 Ohm (low impedance setting), continuous."
Since LAMMs specs were accurate at 4 and 2 ohms, I don't doubt that they are correct about their 1 ohm output (in lowZ mode). One may also safely assume that LAMM rates these at 1% THD...just like Stereophile confirms.
So, your numbers are simply out to lunch.
Speaking of lunch , I will place the test results in your lunch box , who knows .........
WHatever floats your boat A.Wayne.
BTW you never did address the fact that I reached my conclusions about the Lamms not on the Scintillas but on the Thiel CS3.7...a 90+db speaker with a minimum of 2 ohms impedance. Surely you won't tell me that the Lamms are inadequate to drive this speaker too? You look pretty silly already with your inability to read stereophile's test report on the Lamms. The fact that the same issues popped up not on one, not on two but on three different speaker systems is a fact that you have conveniently ignored in your zeal to prove me wrong about the Lamms being able to drive Scintillas just fine (a failed attempt at that).
You look silly without my input Morri, you're pretty good :) and i only addressed your high current low - z rating for the Lamm 1.1 on scinnies , thats what mostly got me started in the discussion , i guess the Thiel's are now your new strawman argument ....
Take a look at the thiels impedance phase, see anything .... ?
Regards..
Read the original post...I make it clear that I am taking them off my list because of how they sounded AFTER hearing them on Thiel CS3.7s...so much for your reading comprehension.
You do know how to entertain Morri, here's hoping you finally get to hear a good system in 2015, not good having the same bad experience every year.
So get well soon and all the best ....
Regards,
Edits: 12/20/14 12/20/14
Fortunately I get to hear a good one nearly every evening...mine.
Morri, best to focus on you Class-D shoot out , maybe toobs will be off your list next ......
Edits: 12/21/14
Mr Cab,Again more conjecture, look at the distortion vs power for the Lamms, the Lamms do 100 watts into 2 ohm before distortion (look at the Knee @ 100watts , where distortion takes off) takes off into clipping, it will be at best the same into 1 ohm. 100 watt Cabbie , your theoretical 400 watts would be approx 3% THD @ 1 ohm. Anyway you should measure, very easy , use any test cd and a meter or a scope and measure 2.83 volt out of the lamm's, then measure with a Db meter at listening position , see , easy !
Look at that ...
Cabbie, you are running the lamm into clipping and you hate how it sounds , not like your toooby stuff where the distortion is Noooice when that happens.... :)100 watts on a scinnie is ok for very moderate none dynamic listening, no one is running scinnies with 100 watts/ch , well no one serious about hi-fi reproduction, so thanks for the info , Lamm 1.1 is bad at below 4 ohms, the measurements tell me that and i concur with you .
Regards..
Edits: 12/17/14 12/17/14 12/17/14 12/17/14 12/17/14 12/17/14
Mr Morricab,
Read again , slowly, that was an actually test done by a mag reviewer , not some opinionated peristalsis from a golden Ear wanton... :)
Sensitivity below 74 db is believable , you should measure Cab and stop trying to bluff your way thru everything. I'm solidly of the opinion, you were never really exposed to SOTA level hi-fi based on your Comments or do you think everyone powering these things with mega watts were just insane , including Jason Bloom.
8 watts .. LOL , 2,82v on a scinnie is 8 watts, go measure ....
Regards
of pontificating which amps are "good" and which aren't. Always ready to dispense your dogma concerning negative feedback, class d, ad nauseam. The consistency with which you jump in with your opinions, which are usually put forth with an air of absolute truth, belies your "I really don't care if you use my opinion or not". Seems you care quite a bit; why else keep a "list"? I wonder how large the readership is?
"In the end, all you can do is listen for yourself" is the most accurate thing I have seen you post to date. Perhaps you might take your own words to heart in the future...
try it! you know you want to!
Your views are always appreciated and are among the first I look for here.
Keep it up!
Its so funny when people like you throw around words like "dogma" and don't even really understand what that means. Dogma is defined as the following:
"1.An authoritative principle, belief or statement of opinion, especially one considered to be absolutely true regardless of evidence, or without evidence to support it. "
or
"2.A doctrine (or set of doctrines) relating to matters such as morality and faith, set forth authoritatively by a religious organization or leader. "
Now assuming you meant number 1, I would say that while I think I have done my research and based on my listening obsreavations have found correlation with different types of amp designs. These designs have been found to generate distortion in such a way that a number of studies would say that most listeners would prefer over the standard design orthodoxy. So, there is evidence to support my point of view and it is both observational and scietifically generated evidence.
Take papers by Cheever, Geddes and others as a basis for figuring out what kind of distortion sound better than others (there is no "good" distortion just more or less audible) and some attempts to numerically catagorize it (Shorter, Geddes, Cheever and others) and I have indeed come up with a list based on available measurements and amps that I have heard first hand. Keith Howard also found interesting things when he added distortion mathematically to music. He found undistorted sounded best; however, he found that the patterns that people like Jean Hiraga found the most pleasing were the least damaging to the recording. So, while no distortion is benign there is less damaging and more damaging.
Declaring which amps I have found to sound good and those I have not is not pontification, nor is it dogma...it is observational science (the foundation of all science is observation and then research into that observation). I am a scientist, more specifically, I am an analytical scientist...I make measurements and devise testing schemes for a living. Starting many years ago, I started listening to as many amps and preamps as possible and started to realise that I was leaning in a particular direction because of the sound I heard and how it compared to my experiences with live, unamplified music. I started to form a hypothesis about what constitutes good sound and started then to find research that has been done to support that hypothesis. I have found a number of papers that support what I am hearing but it is far from perfect science. That much is clear.
For amps I haven't heard I think at this point I can tell from the data if they COULD be interesting or not. Until I hear them for real it is not a fact only a possibility. The LAMMS on paper should be a possibilty but in practice I found that something bothered me about the sound.
In the end, I am sharing my findings, which you are free to accept or refuse but unlike most people I have a clear methodology for finding really good gear. If you think that is dogma then you are mistaken in your use of the word.
If you think my statement that I find Class D to not be good sounding as being dogmatic, well you are wrong again because I have owned three different types of Class D amps and tried many many others. I don't give up after the first listen. It is based on the OBSERVATION that all of the Class D amps I have heard don't deliver really good sound. Not at home, not in shops, not at shows, not at friend's...not!
We had the Devialet (original) in-house (widely considered to be the best Class D) and it was soundly beaten by other amps of more conventional design.
I have heard more Class AB SS amps than I can possibly remember, including flavors of the year, Halcro, Soulution, darTZeel, Vitus (not bad actually), Pass etc. etc. on many many different speaker systems... they have problems like one would expect if you read Cheever and others. Sonically they are missing realism.
I am always open to the POSSIBILITY that one of these Class D or Class AB with a lot of negative feedback will be the ONE, otherwise I wouldn't bother to even try them out anymore...that would be dogmatic...like DISBELIEVER and his views about tubes on this forum. I try them, they fail based on my observations. Based on this repretitiveness of experience my hypothesis mostly holds true. I have yet to hear a pure SS amp that I could live with for the long term. The closest was the Edge NL reference monoblocks but I didn't try to live with them so I don't know how they would fare.
When I say, "I don't care", I really mean it because I don't need your validation for me to decide if I am heading in the right direction or not...my ears and my scientific knowledge tell me that I am. I like to share what I find and I like to debate those who don't agree with me but usually they are like you who haven't a clue and can't offer anything meaningful in way of counter argument. I also don't care about my "readership", maybe I have some maybe not. People do drop me emails from time to time...
Obviously everyone has to listen for themselves...I won't spend your money for you but I am happy to guide those who I am quite sure want a better sound than they have. It is a never ending learning process for me as well but I am largely self-directed (although I have had my mentors along the way as well.) I ONLY decide to buy something based on what I have heard and not on other's opinions...so I take my own words to heart everytime. Only a very few items I have bought without hearing first stayed in my system for long.
what exactly "better sound" is and why do you think you are qualified to determine for others exactly what that is? What's next? Are you going to tell me what food I should like? Which beer is "best"?This is the issue I have with your ilk- you "know" what is "best" because you have "heard" it. The simple fact that there are many kinds of amp topologies, each with their proponents and detractors, should tell you something- that there is no "best". There is only personal preference. Yours is but one opinion in a sea of opinions. What is true for you is not true for everyone...So you have heard a boatload of amps. Your experience tells me nothing about them but rather everything about your subjective preferences.
In truth, your "observations" mean -0- when it comes to what others may like or dislike. You have made blanket statements here repeatedly about the "evils" of negative feedback, class d, etc. You have no evidence to support this, i.e., "dogma"- the simple fact is, there are intelligent, knowledgeable people who think you are full of it and their preference and ownership of amps that use large amounts of it are both evidence and proof to the contrary. Again, what is true for you is not true for everyone- all you offer up are subjective opinions which you like to tout as some universal truth based on "science". I don't need to read a paper on TIM or NF to know whether or not I like the sound of an audio system.
If you want to debate the objective performance, great. That is were science, fact, and logic apply. There is nothing scientifically significant in your observations; science, fact, logic, have nothing to do with personal preference; anyone that is married can verify that... You like to draw these grand conclusions and generalizations based on amp topologies and oversimplifications; you have heard THREE (3) class d amps and have made your pronouncement. Never mind there must be at least 20 or more discreet class d amp platforms on the market and an infinite number of system combinations possible- yes, some amps perform differently depending on the system they are used in...there is no universal correlation-see above.You state: "I like to debate those who don't agree with me but usually they are like you who haven't a clue and can't offer anything meaningful in way of counter argument"...You seem to have "opinion" and "argument" confused: an opinion does not necessarily have to be supportable or based on anything but one's own personal feelings. And this is ALL opinion...I think I am the best judge of my own tastes- you are the one without a clue in that regard. I wouldn't presume to debate the validity of your preferences with you. Your appeal to authority ("I have heard so many SS amps I lost count", etc. therefore I am an expert) is spurious.
And yes, def. 2 fits as well: you do seem to come across like a religious zealot or "authority", who has exclusive access to the one and only holy path to "better sound"...
I could care less what path you are on, much less if you are heading in the right direction, or not. It is nice to know that you only buy based on what you hear, not on other's opinions, yet one can't help but wonder why you would then presume to think that your opinions would mean more to others than what they hear...
Perhaps others are taken in by your "science" and impressed by the long list of amps you have heard. Maybe they also make purchasing decisions based on internet "expert"'s "truths". Too bad for them. I would like to hope that most have more common sense than to take someone else's word on what will sound "good" to them in their system.
try it! you know you want to!
Edits: 12/08/14 12/08/14 12/08/14 12/08/14
"what exactly "better sound" is and why do you think you are qualified to determine for others exactly what that is? What's next? Are you going to tell me what food I should like? Which beer is "best"? "
It's called psychoacoustics and in case you didn't know there are ways to find out what sounds most people like the best.
I haven't just heard it, I have been able to correlate it to a greater or lesser degree, with particular amplifier designs. It just so happens that these designs produce particular distortion patterns that are low in perceptible distortion not in absolute distortion. What I am telling you from my experience is that I find that there are scientific explaantions as to why some amps would be preferrable to others for the majority of listeners.
Objective performance based on an oscilloscope or FFT generator is meaningless in isolation. As an analytical scientist one is always trying to relate a measurement feature BACK to a real world phenomenon. This correlation is where the meaning lies not in the raw numbers. The problem is that engineers have for decades pursued numbers as the ends and not as the means to achieving good sound. They have misunderstood the purpose of measurements in their drive to achieve better numbers.
This was realized a long time ago by D.E.L. Shorter at the BBC and Norman Crowhurst who wrote about the problems that negative feedback causes in signal generation back in the 1950s. Otala later saw a problem with negative feedback loops and speaker interaction. I am not coming at this out of the fantasy blue sky. Other rather smart men laid the groundwork for this kind of thinking. Cheever put it together pretty nicely in his Master's Thesis.
The disconnect between what is heard and what is measured has also caused JA at Stereophile much consternation. When AD likes something a lot that measures rather poorly and MF gets caught that way too sometimes it makes JA wonder what is it that is going on. Geddes explored this in 2 AES papers and found that his new metric fit much better than THD + noise measurements, which if anything had a slight NEGATIVE correlation with sound quality!
"In truth, your "observations" mean -0- when it comes to what others may like or dislike. You have made blanket statements here repeatedly about the "evils" of negative feedback, class d, etc. You have no evidence to support this, i.e., "dogma"- the simple fact is, there are intelligent, knowledgeable people who think you are full of it and their preference and ownership of amps that use large amounts of it are both evidence and proof to the contrary"
I have given reference to evidence about these other technologies it is up to you to read and comprehend. Ownership of those other products is often based on other factors than sound quality...that is often the nature of human psychology.
I call it objective/subjective because while, yes it comes down to individual perception there are clear rules that govern what most of us perceive as "good sound" and they are related to how our ear/brain has evolved to understand soundwaves and harmonic patterns in nature. Screw with what nature produces and you run a high risk of an unpleasant sounding result. If you read Cheever, you will notice that it is also sound pressure level dependent and therefore the sensitivity and impedance of the speaker and how the amp reacts to that also matters.
This is objective, observational science and theory synthesized from studies to link the two. I may not have conducted these studies but I am trained and qualified to take their findings and extrapolate what it means with various types of amplifiers.
" you have heard THREE (3) class d amps and have made your pronouncement"
You have a SERIOUS reading comprehension problem. I said I OWNED 3 different Class D amps and have heard at length about a dozen others.
"Never mind there must be at least 20 or more discreet class d amp platforms"
Heard most of them, including the new N-core from Putseys. I have also heard at length exotica like the Sharp SX-200 and Tact Millenium (and their cheaper models too) as well as Lyngdorf, numerous B&O modules (Jeff Rowland, Bel Canto etc.), T-amps, Nuforce, Devialet, Hypex UcD (several DIY), N-core (mola mola), Zap pulse (my own), PS Audio (my own), other Sharp (my own) etc..
"I don't need to read a paper on TIM or NF to know whether or not I like the sound of an audio system."
And that is the problem. You, unlike me don't care WHY you prefer something. I go looking for the reason I like what I like and continually lean towards certain gear and away from other gear. As a scientist I am trained to investigate the root cause of an observation...you clearly are not trained to do this.
"Your appeal to authority ("I have heard so many SS amps I lost count", etc. therefore I am an expert) is spurious.
"
THis is NOT an appeal to authority. If I had said, "AD thinks all SS amps are crap so I they are crap" then THAT would be an appeal to authority (assuming we both agree AD is an authority on audio). I am giving my firsthand observation, something quite different.
"You seem to have "opinion" and "argument" confused: an opinion does not necessarily have to be supportable or based on anything but one's own personal feelings."
As I have said many times in the past (you obviously read only what you want to read and not the whole post), I have an observation and have found evidence to support what I am hearing (see comments above about research in psychoacoustics and distortion perception) and based on this information have synthesized a hypothesis about what I think should sound good and what I think would not sound good. I make arguments using research that some kinds of amps will be inherently less good sounding based on their designs and the subsequent distortions that those designs invariably produce.
"And yes, def. 2 fits as well: you do seem to come across like a religious zealot or "authority", who has exclusive access to the one and only holy path to "better sound"..."
No, as I have pointed out that I have used scientific observation along with documented research in the field of psychoacoustics...is it possible it is wrong? Probably not completely but I am sure it can be further tuned and improved. I have never appealed to any authority other than the research results from various sources but I let the data there speak.
"to think that your opinions would mean more to others than what they hear..."
People seem to like my advice once they try it...I have had numerous adopter of my system concepts, particularly electronics. Since that is a fact (I would be blind not to notice friends who copy my systems) then I have to assume I am offering some value from my advice. They take my word only as far as giving something a try...if it fits then they try to buy it if not...well then I guess what they hear differs from me.
"Perhaps others are taken in by your "science" "
I am sure you have no idea what is involved in practicing science so I will leave your comment as such. I have over 20 years as a practicing analytical scientist so I think I know a thing or two about scientific method and falsifiability of hypotheses.
Again, your science is flawed. Your "science" as to which topology is "best" may be accurate for you, and undoubtedly some others will agree, but not for all, probably not even for most. Each amp topology has its rabid supporters who will tell you their amp is the "best". Where a subjective factor is involved, there is no singular solution. If there was, there wouldn't be the plethora of products in the market. People can't even agree on whether or not cables, fuses, etc. have an effect, never mind which are "best". How many amps are on the market? 500? How many topologies and variations? Digital (NOS? Tube output? Which chip?)or vinyl? Surely if there was a "best", there wouldn't be as many options available nor would this question continue to be discussed. The simple reality is there is no consensus "best", only different. It is these differences in perception and taste that drive not only the audio market, but nearly every other consumer market.You consistently generalize and oversimplify: there is no one class a or class d topology but many. Lumping them all together is like saying a Honda is faster than a Chevy.
Amps make no sound. They transfer a signal with gain. Systems make sound. In light of the fact that an amp and its subsequent performance is dependent and subject to the system in which it is inserted, again, your theory fails.Personal preference is an individual choice with no right answer. Your pseudoscience falls short because unlike people's preferences, it is attempting to use logic and reason to analyze something that does not subscribe to the rules of logic and reason.
Even if MOST people agreed with your preferences, it does nothing to prove they are "right". Personal preferences are not subject to a democratic rule of the majority. Again, there is no right and wrong. Only different.
Best of luck with your delusion.
try it! you know you want to!
Edits: 12/09/14 12/09/14 12/09/14
For all intents and purposes, this is a 100 watt /ch amplfier and should be used accordingly, Mr Morricab dislikes the Lamm distortion/clipping characteristic.
Regards..
I explained why, your lack of understanding aside, your Dogma wont allow. Firstly i see we have /are talking past each other, for some reason i see your responses , then some only after answering , then noticed you already answered. Then i cant edit, then i cant find the post, then a day later it shows up.Pretty hard to have a conversation that way...
So i go again , the Lamm is really a 100 watt per channel amp , period, this is where it's best sonic merit will take place, it is also the point of lowest distortion, if you pay attn to it' distortion curve vs power.
Unfortunately Mr Cab, is not able to grasp this, the distortion rises pretty fast after the knee and in practical use, the sonic's of the amplfier, any and all amplfiers will change accordingly. From past measurements and observation , we have found that SS amps sound at their best when hovering around 33% of their rated 8 ohm output. If you look at the curves posted by Stereophile you will see the lowest point , then the curve starts to knee upward. This transition is where he will hear this sonic change. Now If Mr Cab , would actually measure his actual voltage in use with a meter or a scope he will see this for himself as he goes up and down with the volume.
250 watts@clipping is not enuff for a pr of scinnies to sound "alive" it will not happen , never heard that and i have measured and tested one, something Cab hasn't done and never will , well, only with conjecture.
The Bias /voltage Scheme used by Lamm is the issue IMO, you have to look at it's 8 ohm rating, you will see the tale and remember distortion goes up as you go thru Z-min, the Lamm is not what i would use on High current, Low-Z drive speakers, like 1 ohm apogee's.
So no I'm not surprised, Morricab is, put the Lamm on a 90db 8/4 ohm speaker and it will sound very different.
Regards..
Edits: 12/05/14
That's why I leaned toward inability to drive reactive loads? But the Apogee? Like its 2nd cousin, the Magnepan, a very benign load. Goodly current needs, but nothing a good amp should not be capable of.
But if the amp can't cut it with fair and reasonable loading, what's to be thought? I have ONE last bullet which just NOW occurs to me. Some manufacturers who make what I guess are called RICHLY biased A A/B amps might have trouble at the A-A/B transition? I wouldn't know a better way to put it or if you gave me a room full of cool test gear, exactly WHAT I'd be looking for as a measurable, but I'm just tossing that out? I'd LOVE to see how the Pass amp handles this transition.
Fini:
Too much is never enough
I think you misunderstand the point. I never said the LAMM had issues driving any of these speakers or that it sounded strained...it just didn't sound nearly as good as expected with some very different systems. Therefore, I take it off my list of recommendable amps.
I don't know how to ADD links to an existing post.
Here is a link to a test of a Beheringer amp by the Power Cube method. Not bad results, actually, when you consider the budget.
Scan down to the measurements section and check out the 'graphic'. That'll explain fairly well about amp power vs phase vs impedance……against output at 1% distortion.
Too much is never enough
Cab,Easy a scinnie is 79db @m with a drive of 2.85v so at 4 M listening distance its 73db with 8 watts , @91dB it will require approx 500 watts , per channel to achieve peaks of 95db stereo pr or more specifically 22.5 amp/ch unclipped .The lamm is not capable , so either you're listening very moderately in a small room or love distortion when listening . Also the Lamm produces its measley 250 watts at 1%thd ,other words, after the kneeing effect. Looking at the graphs published by sterophile this amp sonic sweet spot IMO is at 100 watts /ch and 8 ohm load ...
Edits: 12/02/14 12/02/14
THey produce 250 watts into 2 ohms, if we assume that they can approximately double into 1 ohm again then you are close to 500 watts into 1 ohm.
Second, your estimate is off for a real room the drop is less than you calculate...I know I have done the measurements with other dipole speakers of similar size to the Scintillas. Also, that is for only 1 speaker so you can add another at least 3db for a stereo pair. The real in-room sensitivity is probably more like 79db at 4 meters for a pair.
THis means that you can get close to 100db with a 500 watt amp.
With all due respect, I don't think you have any experience with Scintillas, whereas I have 3 different friends that own this speaker. One friend drives his in a pretty large room with a pair of Classè DR3 switched to monos (90 watts Class A). This plays plenty loud. The other friend uses a Sphinx Project 16, which is 100 watts Class A hybrid with switchable power suppply much like the LAMMs and it works great and plays plenty loud.
You can see this in reviews of the past as well.
Third: The other two Apogee models, Studio Grand and Centaur Major, are NOT the same as the Scintillas. They are moderate impedance 5 ohms and moderate senstivity 87db or so. The sound quality was basically the same with those speakers.
Fourth: The Thiel does not drop below 2 ohms and it is clear that the LAMM produces a fair amount of power into 2 ohms (yes, 250watts is PLENTY for domestic applications) and will drive the Thiels to well over 100db given their relatively high sensitivity. It is silly of you to state that the LAMMs have inadequate power and current for the Thiels.
Cab,
This is getting hilarious , the lamm current limits going from 8-4 , yet you have it doubling going from 2-1 ohm .....:) please Sir, spare me, please actually measure and at the typical listen distance necessary for a scinnie and Im sure i have a little more experience with apogees ( measured them) and speakers in general than yourself.
Typical listen distance is 2.5-3 M for proper integration , please measure with 2.85v drive at 1 ohm (8watt) then do your 100db calculations. Next slap a scope on the amp being used then report back how much clipping distortion sounds good to you .. I'm of the opinion , based on your comments , what you favor might just be the Clipping characteristics of these amplifiers...
Follow me now :
The LAMM , does not have strong current drive ,you dislike the sound of this amplifier because you are running past it's distortion sweet spot, go back and look at the test results ,compare its distortion at 8 and 2 ohm , see something , yes imagine that , measurements do say something ..
Regards
"the lamm current limits going from 8-4 ,"
No it doesn't, the measurements were made with two different amp settings...the impedance switch man, the impedance switch it affects the Class A output of the amp.
I did the calculations correctly prove me wrong.
Now, did you notice the doubling of power from 4 to 2 ohms??? How do you explaing that in the measurements if the amp is current limiting from 8 to 4 as you claim?? Not logical is it? It is simple to explain when you understand that the 8 and 4 ohms are optimized by the impedance switch to maintain Class A power delivery. Into 2 ohms it is nearly doubling and has probably slipped into Class AB.
"I'm of the opinion , based on your comments , what you favor might just be the Clipping characteristics of these amplifiers..."
And I'm of the opinion, based on your comments, that you haven't got a clue about good sound or what can drive what in reality...OR you listen VERY VERY LOUDLY (average 100db+). Honestly, no one likes the sound of clipping and it is stupid to suggest so.
"Follow me now :
The LAMM , does not have strong current drive ,you dislike the sound of this amplifier because you are running past it's distortion sweet spot, go back and look at the test results ,compare its distortion at 8 and 2 ohm , see something , yes imagine that , measurements do say something .. "
Nope, not buying one cent of your argument. Your assumption is based only on what I would consider very loud listening...I don't listen nearly as loud as it would take to stress this amp on ANY of the speakers mentioned...especially the relatively sensitive Thiels and the easy to drive Studio Grands.
No my good friend you are the one clueless when it comes to Hi-Fi and full of nothing but conjecture to boot. I do suggest finding someone to help you with your setup and testing before making these ridiculous statements and get some good amplification for those Apps. :)
Regards
Edits: 12/03/14
Personal attack is always the last resort of the loser in a debate.
You didn't and cannot address a single point I brought up but if you look at the M1.1s successor, the M1.2 it becomes more clear. That amp was tested more thoroughly with all the settings in Stereophile and showed prodigious power into 2 ohms in the high setting (something that wasn't tested by TJN previously). JA ran it more through its paces. Now you could say that the M1.2 is a different amp but only incrementally and the basics are the same.
From the LAMM website (the M1.1 is no longer listed there):
"The M1.2 Reference is conservatively rated to deliver 110 Watts into 8 and 4 Ohms in pure class A operation (high and low impedance settings, respectively); 220 Watts into 2 Ohms, and 400 Watts into 1 Ohm (low impedance setting), continuous. The M1.2 Reference can drive any known speaker. The harmonic structure remains intact regardless of the speaker load, while the extreme clarity is maintained at all power levels."
400 watts into 1 ohm!! Given that what they claim for 2 ohms in the low impedance setting is born out in STereophile's tests there is no reason to doubt the higher power into 1 ohm!!
Measurements in STerophile bear this out at least down to 2 ohms.
If 400 watts into 1 ohm is not sufficient current for you and according to STereophile the M1.2 delivered 790 watts into 2 ohms in the high impedance setting (this was NOT tested by TJN for the M1.1) then I am not sure what you consider to be enough current drive for a speaker.
SERIOUSLY, address the numbers or shut up!
I have also hit you with data on Apogees, about which you are wrong wrong wrong and the best you can do is call me clueless??? You are a joke and it is clear you have no definition for what you consider to be "enough" current.
Do you understand the difference between Class A and Class AB operation? Do you understand that amps are normally optimized for a given impedance for that Class A operation?? Do you not realize that LAMM has a switch on the amp to optimize its Class A operation for different impedances??? Do you not understand that much more current is available once the amp leaves Class A operation (as evidenced by the M1.1 near doubling from 4 to 2 ohms and the increases obeserved in the M1.2 as measured by JA).
Address this or stay silent admitting you are just plain wrong about the amp, regardless of how it sounds.
Cab,Please stick to the opinionated reviews , i enjoy those, very much so, worse i agree with most of your selections( not all ) but this, yet your rotational science is getting to me, not meaning to be spiky and with all due respect , you are technically clueless , do you have any measuring equipment , do you even or have ever tested any type of gear..?
Hard correcting you when you make up your own opinionated science, sadly too are the plethora of opinionated mags like TAS populating audio ..
Please read carefully stereophiles test on the Lamm, it current limits tremendously into 2 ohm, now anyone can like audio equipment for what ever reason , this is not an amp someone should use with low sensitivity high current drive speakers ...
Regards ..
Edits: 12/03/14 12/03/14
Technically clueless?? Hardly. Not sure what you mean by rotational science because I am looking at the numbers rather directly.
I have tested gear and have digital oscilloscope and access to a THD meter and computer based measurement tools.
Now to the meat of this disagreement. Stereophile's measurements.
I quote:
"In this figure, it's clear that, with the impedance switch set to the most appropriate setting, the M1.1 puts out almost identical power into both 4 and 8 ohms."
The main point to point of this quote is impedance swich set to the most appropriate setting. What do you think that switch is doing?? Obviously the amp does not have output transformers so it is adjusting the voltage/current delivery of the power supply. It is keeping the amp in Class A for these two impedances and as a result the power output is the same.
" Lamm M1.1, distortion (%) vs output power into (from bottom to top at 1W): 8 ohms (impedance switch set to 6–8 ohms), 4 ohms, and 2 ohms (both with impedance switch set to 1–6 ohms)."
With these settings the power into 4 ohms is 138W into 4 ohms (18.4dBW) (114V line); and in 2 ohms it is 230W into 2 ohms (17.6dBW) (115V line).
Now, please explain to me how you consider " it current limits tremendously into 2 ohm," when it is producing nearly double the power into 2 ohms...please explain how nearly DOUBLE the power constitutes current limiting. Seriously enough of the claiming I am clueless and start proving your BS. The data doen't support your claims!!
This is so far off technically Cab , too much to correct here , how can the Lamm have enough current to drive anything but an 8 ohm speaker, it current limits from 8-4, it barely increases it's 8 ohm rating into 2, so your math is way in every direction.
The amp will have an issue on those type of load, period, Wrong Horse, wrong course ..
Regards
Edits: 12/02/14
It is clear that you don't understand that the amp has two power supply ranges. A higher voltage/lower current mode and a lower voltage/higher current mode. In the low impedance mode it nearly doubles power from 4 to 2 ohms.
What JA didn't test is what happens going from 8 ohms to 4 ohms when the amp is in the 6 - 8 ohm mode. My guess is that it double but is no longer in Class A.
To reiterate; the design is Class A into 8 ohms in the 6-8 ohm mode and Class A into 4 ohms in the 1-6 ohm more. This is why it has the same power rating at both loads with the switch in power supply (Reread Stereophile you will see how it was tested).
What is also clear is that in the 1-6 ohm more the amp almost doubles in power from 4 to 2 ohms and also probably goes from Class A to Class AB into the lower impedances.
Let me ask you, how do you think its possible for an amp to have no increase in power from 8 to 4 ohms and then magically doubles going to 2 ohms??? Pretty bizzare unless you know that the amp has actually 2 ranges where the amp is kept in Class A for best sound.
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