gene;908200
I spent many years thinking everything in audio could neatly be measured and quantified. If fact I am pretty anal retentive about this beyond just audio but I am slowly realizing that we don't always get the whole picture from text book measurements & analysis.

This is a good topic for an article that I plan on writing when I find the time.

I do the most exhaustive testing in amplifiers that I've seen compared to any publication. I've even spoken with the folks at Audio Precision and they were impressed with my methods. I am still not 100% happy however as I'd like to do more but as you pointed out, my time is limited and I am the only person on staff that does amplifier measurements for Audioholics.

Distortion audibility is a complex topic one that the folks at AP also discussed at our 2008 SOTU event in this rather boring but interesting video:

Audio Precision Amplifier Testing Methods Class — Reviews and News from Audioholics [audioholics.com]

Again sometimes text book theory doesn't always apply to real world. I found this especially true with loudspeakers and somewhat applicable to amplification.

IHO as an engineer, even subtle differences have equations behind them and there are measurements or a combination of measurements that will correlate to how an amplifier sounds. I firmly believe this. Maybe its never been done before to that extent but I think it should be. That way audiophiles and people selling snake oil ( not implying anything to you ) can be held accountable for the travesties in this industry.

Speakers are different from amps only from the perspective of room interaction espcially with respect to seating position. There are too many variables in/for a room to even think that measurements would describe accurately how a speaker sounds. I realize that even mic placement can alter the measurements of a speaker. Its far more complicated from a variables point of view than amps that for sure. If one had a thousand years, maybe one could accurately model speaker interaction with its room.

I look forward to the article. It may change my opinion on amp's sonic signatures

GranteedEV;908190
Um..... why exactly can't you measure a worst case test load?

It sounds to me a classic case of "The measurements are incomplete therefore the listening is more relevant"

But for electronics I'm not sure that should ever be the case given the dubious nature of the industry. The measurements should always be weighed greater. If that means measuring into a 1 ohm load @ 75 degree phase angle for a $5000 amp @ 10hz to 22khz, I don't see why not. It's pretty insane but the measurements should always represent a worst case scenario not a middle of the road scenario.

Likewise with loudspeaker measurements. Why only measure 30 degrees off axis when the sound at 60 or 70 or even 150 degrees off axis has been shown to affect perception?

I understand as a reviewer time constraints etc come into the picture but it's unfair to do half-measurements - and then claim that they don't help identify what you heard.

I'm not criticizing your measurements here Gene. They're great and appreciated as are the subjective commentary. But It's a bit disheartening to see you post the measurements and then claim they're inadequate relative to your experience. If your own speakers are a more complex load than the test signal, then as pretty much the publication leader we expect you to address that objectively rather than use the limitations of the measurements as evidence. I don't really like the idea that something that can be heard but can't be measured. That's awful close to "cable" territory to me. It can either be measured or you choose not to/lack the capability to measure it.

Sorry to rant especially since this was a really good review but your comment that you can hear things that you can't measure just doesn't sit well with me. I'll admit my measurement capability compared to yours is infinitesmal but I also don't make such claims. I know you know this but it feels you just word things in a certain way that gives teh wrong impression.

It seems like a very good topic for an AH article - what aspects of amplifiers when isolated - are actually audible in an ABX / single blind test? I have no doubt that if you can hear it, you can measure it but complexity is the keyword.

I spent many years thinking everything in audio could neatly be measured and quantified. If fact I am pretty anal retentive about this beyond just audio but I am slowly realizing that we don't always get the whole picture from text book measurements & analysis.

This is a good topic for an article that I plan on writing when I find the time.

I do the most exhaustive testing in amplifiers that I've seen compared to any publication. I've even spoken with the folks at Audio Precision and they were impressed with my methods. I am still not 100% happy however as I'd like to do more but as you pointed out, my time is limited and I am the only person on staff that does amplifier measurements for Audioholics.

Distortion audibility is a complex topic one that the folks at AP also discussed at our 2008 SOTU event in this rather boring but interesting video:

Audio Precision Amplifier Testing Methods Class — Reviews and News from Audioholics [audioholics.com]

Again sometimes text book theory doesn't always apply to real world. I found this especially true with loudspeakers and somewhat applicable to amplification.