Wow! I’m surprised this old thread is still alive. I’ve done a lot of reading on this subject over the years and learned for the most part what was said earlier in the thread was/is true. Too bad I was so thick headed back then.
FWIW – Out of stupid dumb luck I ran across a pair of Outlaw 7900s brand new in the boxes on eBay for a very good price and went with those. Expensive, but still a lot cheaper than going my original route, and they take up a whole lot less space. As to be expected, they do sound similar to the Yammies but I do hear differences. The Outlaws are quieter with a lower noise floor, dynamic range and transient handling is better, and low-level detail seems to come through clearer. So even though there hasn’t been any major changes in the basic design of amps, the minor changes that have been made definitely do add up after 30+ years of evolution. A win/win for me.
Seems like you are one of those who managed to learn, and not blindly follow the logic of "if amps sound the same, why are there different ones made and people willing to pay a fortune for some...." kind of non sensical arguments or other hearsay about how even amps designed for transparency would sound warm, medium warm, cold, punchy, forward sounding, blablabla kind of BS.
This is indeed an old thread, during that time iirc., we typically would get such posts about "amp sounds" weekly, but a lot of the members have learnt too over the years and we have been getting much fewer posts of such nature and more are asking more objective questions. For example, instead asking which amp would match their bright, forward sounding speakers, they would ask instead, whether the amp being considered could drive their speakers that are known to be "difficult to drive", or power hungry kind of more sensible questions. It is so silly to think people need to match the sound "signature" of amps to speakers, as though we need some kind of dating apps in order to find good matches lol.., instead of relying on specs and measurements. Dating apps would do a good job to match people up, but amps are designed, build based on known matured science and their characteristics, unlike humans, are totally measurable.
Regardless, the arguments will never die for the obvious reasons. Certain facts however, remain unchanged, and I would think most can agree on, such as:
Different amps will sound different, if not compared on apples-to-apples basis such as:
Not level matched, one amp is pushed closer to its clipping point, whereas the other amp is nowhere near its clipping point, one amp has audible noise (such as some of the vintage amps), tube amps purposedly designed to have audible distortions (say 0.1%), one amp has high output impedance, whereas the other has output impedance well below 0.1 ohm, one amp is too current limited for the speakers used whereas the other amp is not limited in voltage or current for the same speakers and for the same test conditions, and the most important one is, if one know which amp one is listening to against the other one being compared, he would naturally hear (perceive) differences between the amps. This "fact" has been proven in many/various studies.
Above are just some examples of the reasons different amps could sound different.
Based on objective facts, once you get pass the entry level amps, such as you Outlaw 7900, you can then almost assume that as long as you use the amp within it's output limits (think voltage and current, not watts), it will sound the same as any other amps that have comparable specs in SNR/DR, FR, THD+N, cross talk, output impedance (or the so called damping factor), input impedance, and IMD (usually low if THD is very low), just to name the important ones.
The Outlaw 7900's specs checked all the boxes and based on website info:
Signal To Noise Greater than 120dB; rated FTCfull bandwidth power
So yes, it should be near silent for normal use, even in a relatively quiet room.
Since you have been doing a lot of reading, I am not writing this long post to convince you. Just like as I mentioned, we haven't seen much of post on the amps sounding different/same topics so I thought it wouldn't hurt to sort of comment on the first resurrected post (the one before yours) since 2015.
