Which watts are the right watts in SS amps?


Hello Sports Fans!

More than a few people over the years on these pages have said only those SS amps which double down in output power as impedance drops are truly special or worthy amps. Eg., 200 @ 8ohms; 400 @ 4 ohms; 800 @ 2 ohms; etc.

Not every SS amp made does this trick. Some very expensive ones don’t quite get to twice their 8 ohm rated power when impedance halves to four ohms. BAT, darTZeel, Wells, and Ypsalon to name just a few.

An amps ‘‘soul’’ or it’s ‘voice’ is the main reason why I would opt in on choosing an amp initially and keeping it. Simultaneously , I’d consider its power and the demands of what ever speakers may be intended to be run with it or them.

I’ve heard, 80% of the music we are listening to is made in the first 20wpc! I’m sure there’s some wisdom in there somewhere as many SS amps running AB, are biased to class A Only for a small portion of the total output EX. 10 – 60 wpc of 150 or 250 wpc.

After all, any amps true output levels are a complete mystery when anyone is listening to music anyhow.

I suspect, not being able to actually measure true power consumption, the vast majority of listening sessions revolve around 60wpc or so being at hand with traditional modern reasonably efficient speakers.

Sure, there are those speakers which don’t fit into the traditional loudspeaker power needs mold such as panels or electrostats, and this ain’t about them.

The possibility of clipping a driver is about the only facet in amp to speaker matching which gives a person pause while pondering this or that amplifier.

I feel there is more to how good an amp is than its ability tou double output power with 50% drops in speaker impedance.

However, speakers are demanding more power lately. Many are coming out of the gates with 4 ohm ‘nominal’ IMPs which lower with fluctuations in frequency. Add in larger motors on larger drivers, multiple driver arrays, and on paper these SOTA speakers appear to need more power.

IMHO It is this note which introduces great concern.

I’ve read every article I can find on Vienna Acoustics Music. Each one says give them lots of watts for them to excel.

Many times good sounding speakers I’ve owned sounded better with more power, albeit from arguably a better amp.

I tend to believe having more than an adequate amount of cap power is indeed integral. … naturally the size and type of transformers in play possess a strong vote for an amps ability to successfully mate with speakers.

Controlling a driver’s ability to stop and restart is as well a key to great sound and only strong amplifiers can manage this feat. Usually this gets attributed to ‘damping’ factor, but damping as I read it is more a shadow than a tangible real world figure as it depends on numerous factors. Speaker cable length alone can alter damping factors.

A very good argument exists about those mega watt amps voices. Each 500 or 600 wpc amp or amps, I’ve heard have had stellar voices too, not merely more watts.

So is it predominately these mega watt power house amps souls or their capacities that fuels the speakers presentation?

Would you buy an ‘uber expensive’ amp based more on its voice or soul, than on its ability to output loads of watts, even if you feel the amp may be somewhat under powered for the application?

Choosing this latter option also saves one money as the more powerful amps do cost more than their lower outputting siblings.

Please, share your experiences if possible.

Tanks muchly!

blindjim
I’m also not convinced that the drawbacks of feedback are so bad it should be completely avoided.


A little story about feedback.

An output transformer "GOD" wound up some very nice massive cores for a friend of mine who was his buddy cost no object, interleaved to the hilt. I ended up with these cores when he passed away.
The transformer "GOD" I got in touch with and he got me to get some special C-Cores from Egypt where apparently is the best silicon. These transformers could be changed via the separate interleaved winding tabs for 16,8,4,2,and even 1ohm.

They sounded magnificent on a big pair of 150w tube monos I had, and I decided that maybe because the transformer were that good that there was maybe no need for feed back to help them have a lower output impedance. So I put on a variable feedback pot that could be changed from 30db down to zero. Adjusting the volume for the change in gain, it was clear as a bell that zero feed back was by far the best and because the transformers were that good the bass remained tight and dry.

So that proved to me, feedback is good in tubes to get better bass with lower output impedance, but it does have a negative effect on the rest of the music.

Cheers George 
Go ahead and spend gobs of money on those pure class A amps that burnout after 7-10 years
Any truth to this? (i.e. is a class A amps life span known to be less than other designs)

If so, is there anything that can/should be done from a practical perspective to prolong the longevity of a class A amp?

Thanks.
If so, is there anything that can/should be done from a practical perspective to prolong the longevity of a class A amp?

Thanks.

Keep them biased right, Pass recommends palm hand test on the hottest part of the heatsinks being able to keep them pressed for at least 6 seconds (no brickies hands) any shorter and it’s running too much Class-A, and also keep them in a well ventilated spot.

Cheers George
Post removed 
Go ahead and spend gobs of money on those pure class A amps that burnout after 7-10 years
Any truth to this? (i.e. is a class A amps life span known to be less than other designs)
No. We've been making class A amps for the last 41 years, and recently serviced one that had been in the field since 1988.

Just make sure that they can get adequate cooling and they are fine.

I'd like the process of component pairing to be less guess work and more analysis.
Me too- but its not going to happen unless the audio industry cares enough about quality of reproduction to address the shortcuts (including measurement issues) that have been taken so often in the last 50 years. Until then, equipment matching is a thing :/