Audio Science Review = "The better the measurement, the better the sound" philosophy

French or regular?

@tonywinga My first turntable was a Dual 1209 and a 1960s tube Kenwood receiver!  I was 13 years old.  I had tubes with cages to protect against my young daughter (vice versa). 

My last 31 years, I've had a dedicated pair listening rooms with closed doors because for 24 years I have used high voltage uncaged tube amps with top caps (.6P7S - 6BG6 G Beam Tetrode power tubes).  Only my wife and I turn the amps on/off and the cats who occasionally enter with us ignore the equipment (sleep in front of the speakers).    

@kota1 I have gone to revival movie theaters to view 30s and 40s movies from safety prints where I experienced close to what audiences saw when they were new.   I have two 4K 75" Sony LCD TVs which are were top models 3 and 5 years ago and are quite nice still.   Too bad I haven't combined the audio and video rooms together (I use a Yamaha CR620 receivers hooked up to a pair of MB Quart 980S and ADS L620s).  Eventually, I will replace the MB Quart with Legacy Signature IIIs.  

@crymeanaudioriver Note fellow Audiogon posters, this member signed up to annoy us on this forum, much like the lectures from Amir.  He is a regular on ASR.  Try to ignore him (unlike ASR where trying to ignore someone who is not a follower of all things Amir gets you defamed and booted).  

By crymeanaudioriver:

@fair  -- All that typing, and all that work, but not even a minute of research to understand why a resistive load is used for amplifier testing.

"Cute", isn't it? A typical example of a "gentlemanly" statement considered normal at ASR these days.

It took me a bit longer to understand this item. I think I spent almost 30 minutes, but now I am comfortable with the answer.

At this point a replying person usually goes into explaining what relevant educational, professional, and life experiences he had over prior 30 years to come to his understanding of the issue at hand. I know better now. I won't.

I also know now that everyone uses resistors for testing including Stereophile. Stereophile has a simulated speaker load, but this measurement provides no additional information that cannot be ascertained in other measurements.

This is emotionally a very strong, and technically a very wrong statement. For details, please see:

https://www.biline.ca/audio_critic/mags/The_Audio_Critic_20_r.pdf (page 16 on)

and

Measuring Power Amplifiers with Reactive Loads

I quickly found at least 6 and probably there are many more discussions on using complex loads for amplifier testing on ASR. I had to Google to understand some of the terms, but I muddled through. Even the stronger proponents of complex load testing, after the discussion progressed, agreed it was of limited and would only be valuable with an extreme speaker and a marginal amplifier.

I did such search too, yet got quite different results. There are a number of threads where the issue comes up, yet remains unresolved. For instance:

hypex power ratings

What is it about McIntosh?

KJF Audio MA-01 Review (Multi-channel Amplifier)

Review and Measurements of Accuphase E-270 Amplifier

 

One thread, dedicated to the subject, appears to be expressing virtually all conceivable points of view, yet it is inconclusive as well. Also, quite a few replies there were redacted: one can see quotations from them and references to them, but not the original replies in their entirety.

Complex Load for Power Amplifier torture testing

 

I thank you for encouraging me to look into this as I sort of understood it, but had not delved deep enough. It was a less complex topic than I was expecting.

Here we differ too. As technical as the dedicated ASR discussion thread was, it didn't touch on stochastic behavior of non-linear time-dependent systems, of which a practical multi-transducer loudspeaker is a prime example.

Attaching such a system to an approximately linear, approximately time-independent power amplifier leaves the combined system still non-linear and time-dependent.

The math describing non-linear time-dependent systems is far more sophisticated than the one underlying the simple measurements that Amir uses.

Providing strings of measurements that all demonstrate factors beyond anything that can be heard by anyone or have any effect whatsoever on the sound that can be heard is totally futile, making decisions on such data is totally ridiculous.