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In Reply to: RE: But posted by A.Wayne on December 08, 2014 at 08:17:01
"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.
Follow Ups:
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
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