All Amps Sound the Same....

Onhwy61 - Rowland amps sound great because of Jeff Rowland and not any measurements.

Atmasphere amps measure quite bad (THD=1%, DF=1) but sound great.

I don't want to go into details why "feature massive use of negative feedback, outrageously good measurements and supposedly outstanding sound quality" isn't possible, but if you think of soulution 710 amplifier then you're mistaken. This particular amplifier has zero feedback:

http://www.axissaudio.com/amplifiers/710.htm

It is also mentioned in 6 moons review that 700 amps have zero feedback. Anything can be designed. The issue is cost ($40,000).

Icepower that you mentioned measures average. Popular 1000ASP module has only 38kHz bandwidth, 60deg phaseshift (20Hz-20kHz) and 0.2% THD

Onhwy61, "I think the audiophile world is on the verge of what might be a significant advance in sound reproduction quality as engineers are becoming more knowledgeable about what to measure and how the interpret the data."

Can you elaborate on that, please?

Trelja, this may not be that coherent an explanation, but this is what I'm thinking...

A generation ago the engineers and tech involved in grand prix motorcycle racing basically had a stop watch, temp gauges and the comments of the rider to tell them about the race track performance of the motorcycles. With so little information the rider's comments about feel and responsiveness dominated the motorcycle's development. Today the situation is vastly different. With multiple computer setups data is streamed in real time or downloaded for analysis. The rider's comments are still important, but they are not necessarily the most important source of information about how to get the bike around the track faster. The better race teams have learned gather and make use of the data.

I think we're at a similar point in audiophile equipment design and manufacturing. We no longer have to just rely upon our ears and a seat of the pants explanation of what is going on inside the components when they are playing music. We're no longer stuck with static test signals and can now actually observe circuit behavior under dynamic conditions over time. At least that's what I am led to believe from reading manufacturers' papers. As an industry we're moving beyond frequency response, THD and S/N. I think that's a very good thing, but at the same time it doesn't guarantee better sounding components. I do think that over time the improved analytical capabilities available when used by skilled engineers/designer will eventually produce better components. We're always going to have to trust our ears, but we're also going to have to trust the measurements too.

Kijanki, from reading your posts I think you know way more about electronics than I ever will. I acknowledge that and I respect you for that. However, when you say that you should avoid products that measure well -- I just have say that don't make no sense.

As far as Soulution and NFB -- some of their product blurbs say they don't use it and at the same time there are printed comments from their designer saying he's taken heroic measures to implement high speed NFB circuits into the product.

Onhwy61 - I'm only saying to avoid products that measure too well for the price, because something has to give and often it is sound. Soulution monoblocks look very impressive but I'm more withing Rowland 625 range.

I agree, that some kind of dynamic test would help not only designers but also buyers to make right decisions, but so far I can see many key specifications missing or without reference point. We all learned, one time or another, that equipment tested with sine or square waves behaves completely different with music. Often not a good specification but rather company name is wort paying for. I ended up buying small Rowland amp knowing that Rowland for over 20 years produced only very good amps. My next amp is likely to be Rowland.

I'm all for better testing, being frustrated with trial and error while pieces are often not available for trial (heavy or expensive). To add insult to injury some dealers start charging for in store demonstration. Well, it is what it is.

Onhwy61, the analogy with motorcycle racing is one I must applaud you for!

This is the argument I've been making here and there on this site over the past year or so. Quite simply, the move of measurements from algebra to calculus.

Previously, in motorsports, the means of measurement you enumerated dealt with the steady state - algebra. As you also noted, because of the intense competition (and available processing power) they were forced to transcend that realm of operation, and now deal in the real time measurement of acceleration/deceleration, forward/reverse, stop/start, etc - calculus. At that point, folks are able to digest this data, make adjustments, and ultimately implement things which yield tangible benefit to the craft.

It would be nice, as you say, that this transition also took place in audio. Unfortunately, I must say that I am not as sanguine as you are about how this will proceed in our niche. In my opinion, with few exceptions, this lies beyond the ability/capability of the designers currently in the high-end audio hobby.