Modern tube amplifier designs?

[xenu]

seen some post from 2004 but no follow ups.
Any updates?
original article


Thanks in advance.

[xenu]

As a newbie to the tube world, I'm following this forum for quite some time.
My impression is that most of the designs discussed here are based on 50-70s designs.

Since than a lot had changed:
1. The requirements are more stringent (noise floor, dynamic range)
2. There are much more advanced solid state electronics available for control and regulation.

While I've seen few high voltage regulation circuits, I have not seen an amplifier design that takes advantage of solid state capabilities such as auto-bias control (vs. fixed or manual). Not to mention heresies like (negative) feedback.

Am I'm missing the modern designs that exist out there?

[SpreadSpectrum]

Morgan Jones's Crystal Palace comes to mind. My current project also comes to mind as it is all active regulated and employs a bias servo to maintain bias current balance.

It's true, many here are stuck in decades past and will gladly pay big money for a 10 pound choke to do a job much better and much cheaper done by a bit of sand.

[leadbelly]

Originally posted by xenu
As a newbie to the tube world, I'm following this forum for quite some time.
My impression is that most of the designs discussed here are based on 50-70s designs.

Am I'm missing the modern designs that exist out there?

Well, if you have been following this forum for a long time, you certainly have not been paying much attention. No modern techniques? No solid state? LED bias, MOSFET source follower, numerous SS/hybrid CCS designs, nothing ring a bell? Maybe you should turn off the TV while you are "following this forum"?

[nhuwar]

What do you mean no led bias, it's SY favorite method LOL

[tubelab.com]

When I first started talking about CCS loads coupled with Mosfet followers (PowerDrive) for driving DHT's the die hard tube heads were not pleased. Many sent me some ugly emails about sandy tube amps, and there were even a few posts here.

Now that the Tubelab SE has been around for a few years, the people who have actually heard one like them enough to build their own.

The DSP controlled cathode follower is still a bit too much for many to take, yet.

[ray_moth]

It's true, many here are stuck in decades past and will gladly pay big money for a 10 pound choke to do a job much better and much cheaper done by a bit of sand.

Love it!

Actually, there are more than a few more adventurous souls here who are happy to make use of what modern SS devices can offer. I believe in using the best device to get the job done. If I read a post that says something to the effect that "SS has no business in tube audio circuits", I stop reading that post because to me that's just dogma (a.k.a unsubstantiated opinion).

[aardvarkash10]

A quick scan will show that the ones who rail against sand in their glass are the same ones who spend squillions on hydro-epoximide-infiltrated oxygen-free interconnects and other such twaddle. It seems their hatred of modern only reaches as far as an RCA socket... Their hypocracy however knows no bounds.

[SpreadSpectrum]

there are more than a few more adventurous souls here...

I know and it is a pleasure exchanging ideas with you. You are very much appreciated. We are unfortunately a minority to what I like to refer to as the 'CLCLCLCLCRC filter' crowd.

[atmasphere]

What qualifies as a new tube design? Something that was not around in the 50s, 60s, or 70s?