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In Reply to: RE: I disagree with your assessment posted by morricab on December 02, 2014 at 02:00:23
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 12/02/14Follow Ups:
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!!
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