Are future improvements in Amp/PreAmps slowing to a crawl?


don_c55
@kosst_amojan

The gold standard is class A and nobody has come close to building a class D amp that touches the qualities of class A. Even the very best draw very mixed opinions. Amplifiers are art. Every amplifier imparts distortion with some character. For those of us accustomed to low order distortion imparted by simple topologies using as few gain stages as possible, class D isn't even on our radar.
It may interest you to know that our tube amps are class A with only one stage of gain. It can't get a whole lot simpler than that.

And I've yet to hear a class D amp that can keep up. But it would be a mistake to simply write off class D. Its still on the steep part of the price/performance curve.
I think in General,  Nelson is exactly right... when it comes to the traditional designs of A... A/B anyway.  I look at an old Sumo or Gas Amp that Mike Bettinger mods.  He changes caps & resistors to newest & best as well as switching a bipolar to a Jfet,  the results are that you have a 30 to 40 year old amplifier that competes with modern amps or  Take an old PS Audio 200C.... from 1985.  Yes it can be beat, but if comparing apples and apples,  it still stands up with modern amps.  So what I see is better devices,  better parts, not necessarily better design.  I think really that was what Nelson was referring to is that He jumped in a big way to LISTEN to Input/output devices to build the best components that he could muster, based upon the best parts that he could find and how those individual parts sound,  it wasn't necessarily a revolutionary new design.  With that said.  I agree that we have newer technology that will matter.  Class D output Is pretty amazing... I've taken abletec modules and built some of the light weight little amps that don't get hot, yet are very musical amplifers.  So, I see both sides and suspect that some new input or output part will come along for Nelson or someone else to make the Next Best Thing. 




Why would a respected tube amp designer want to play with something very different?
Anyone who thinks the best Class D is the lesser technology or always inferior sounding when compared to Class A is just not paying attention.

"Will it sound like what you like?",

That is a completely different discussion to have. If anyone can make a _better_ amplifier than the best linear and Class D for normal speakers I cannot hear it.

However, lots of ways of making amplifiers sound different, juicier and more colorful.

As someone once told John Coltrane (I believe): "You can't make it better, only different."


Peace,

E
Speaking of Pass, it is important to note that the model for a high quality SS amplifier was first really codified in the late 1970's by the work of the late Dr. Marshall Leach Jr. Using bipolar transistors Dr. Leach's proposal set the blueprint for every SS design going forward for decades.

Almost 40 years after this paper, I would love to have a panel discussion with Pass, Curl, Carver about how far we have come from then, what Leach got right, what he got wrong, or what they think Dr. Leach would have done better with the parts we have today.

Best,


E