Modern "High-Gain" Amps

[Enzo]

No.

Idle dissipation is just a static amount, not related to audio power. I think my best analogy is idle speed on your car engine. My truck idles at about 500rpm. But if I were to goose that up to 700 or 1000 rpm, it would have zero affect on how fast the car can drive or the horsepower it could generate.

I don't want to spark the same tired debate, but there are ways to look at amp power. Ultimately the power rating is a measure of how much audio power it can put into a speaker load. This comes from the power supply fundamentally, but also is influenced by the tubes involved, and the circuit. The debate? Some want to measure power like hifi: how many watts into the load without distortion. My position? What if the amp is distorted all the time? Does it put out zero power? I consider it the amount of energy the amp can put into a speaker. I will let others worry, "they SAY it is a 120 watt amp but it only puts out 96 watts."

[trem]

Yes...Thanks.
I understand what you are saying.

So back to these "high-gain" amps. What i keep reading is that the amp designer is getting All/Most of the tone and character of his amp from the preamp, and the power tubes are simply there to drive the speakers and make the amp audible.
This Marshall JVM for example. Would it make just as much sense then to do away with the power tubes and OT and simply use a Solid State Power Amp.?
Or are they still benefiting from the "interaction" of tubes and a Output Transformer to develop the sound they are after.
Thank You

and i guess you would also ditch the PI tube.?
i suppose this would all start to take its toll on the sound of the amp, wouldn't it.?
Thanks Again

p.s. I am on a fairly "old" computer. It DOES have a calculator, but no matter which button you select, it wants to add everything.

[eschertron]

Yes...Thanks.
I understand what you are saying.

So back to these "high-gain" amps. What i keep reading is that the amp designer is getting All/Most of the tone and character of his amp from the preamp, and the power tubes are simply there to drive the speakers and make the amp audible.
This Marshall JVM for example. Would it make just as much sense then to do away with the power tubes and OT and simply use a Solid State Power Amp.?
Or are they still benefiting from the "interaction" of tubes and a Output Transformer to develop the sound they are after.
Thank You

While line out-to-mixing console tends to leave people unimpressed, my crystal ball shows the "modern amp" has a tube tone/distortion generator in front, and a SS power section. There's quite a bit of understanding on how tube output impedance affects the sound, and quite a bit of engineering on how to mimic it with SS components. It's going that way

and i guess you would also ditch the PI tube.?
i suppose this would all start to take its toll on the sound of the amp, wouldn't it.?
Thanks Again

My understanding is that the PI is part of the power amp. Especially when there's a loop insert after the Preamp and before MV/PI.

[Enzo]

yes, the PI is part of the power amp.

[eschertron]

and i guess you would also ditch the PI tube.?
i suppose this would all start to take its toll on the sound of the amp, wouldn't it.?

I think part of the appeal of 'tweed' and other older pre-MV amps is that the sweet spot involves a bit of PI and power tube distortion. It's not easy to build a circuit with preamp tubes that mimics this behavior, from sag to the sound of pentodes in push-pull. But this is not the 'high-gain' sound, as the preamp does most of the tonal coloring.

[nosaj]

I think part of the appeal of 'tweed' and other older pre-MV amps is that the sweet spot involves a bit of PI and power tube distortion. It's not easy to build a circuit with preamp tubes that mimics this behavior, from sag to the sound of pentodes in push-pull. But this is not the 'high-gain' sound, as the preamp does most of the tonal coloring.

makes me think of Ray Wylie Hubbard's Snake Farm. It just sounds nasty.

nosaj

[Justin Thomas]

Fender's Prosonic was an uber-gain (for the time) amp, and you could leave it at a nice tube-rectified hot-cathode-biased setting, and crank the Gain & Volume knobs on 10... I won't say whether it was pleasing or not, but, it was... errrr, interesting? But it definitely had all of the above! If you could take it. I could.

Justin

[The Dude]

Ah yes, the "Zinky". You could get a lot of different tones out of those because of the way the controls interacted. IMO, a pretty versatile amp- not just a gain monster,...... although it could do that too.

[Chuck H]

Bruce Zinky picked apart that design for years. So much so you'd think he didn't like it. I read his postings on more than forum stating things like the amp only sounds good with certain speakers or the plate to grid caps should be removed, etc. I had one. I was impressed enough that Bruce became a minor hero of mine WRT design. I met him at the 2009 winter NAMM show and it turns out he's sort of weird. Not in a bad way. Just one of those guys that's really smart but lacks social skills. He was alone in his Supro booth and just seemed nervous, most of what he said was a little odd and keeping a conversation on topic was impossible.

[Zozobra]

Yes...Thanks.
I understand what you are saying.

So back to these "high-gain" amps. What i keep reading is that the amp designer is getting All/Most of the tone and character of his amp from the preamp, and the power tubes are simply there to drive the speakers and make the amp audible.
This Marshall JVM for example. Would it make just as much sense then to do away with the power tubes and OT and simply use a Solid State Power Amp.?
Or are they still benefiting from the "interaction" of tubes and a Output Transformer to develop the sound they are after.
Thank You

and i guess you would also ditch the PI tube.?
i suppose this would all start to take its toll on the sound of the amp, wouldn't it.?
Thanks Again

p.s. I am on a fairly "old" computer. It DOES have a calculator, but no matter which button you select, it wants to add everything.

Depends on the amp and what tone the user wants, but some stuff sounds fine without the PI and power amp. This is an Engl backmore recorded using the FX loop send for example:
https://soundcloud.com/tjore/engl-bl...direct-in-test

Here is the Engl E530 preamp straight into an interface.
https://www.youtube.com/watch?v=7YjGal6ABqg
https://www.youtube.com/watch?v=-lKlcymOgb4

Both recordings use impulses/speaker sims and sound pretty much how I would expect them to if they'd mic'd up the cab.
Now of course neither of these preamps are all that subtle in their mangling of the input signal to say the least which helps.

More traditional marshall tones don't fair as well but they certainly aren't bad when the PI/PA are omitted

JVM: https://www.youtube.com/watch?v=o1bBYv-7pPE
DSL: https://www.youtube.com/watch?v=CuaZxmf_ddM

So we've established that with a bit of trickery that a tube pre can sound more than passable.

One notable hybrid amp that springs to mind is the Verellen Kalaloch. I can't find any good demos of it at the moment but that is two independent amps in one box. There are two clean tube pres, most likely fender derived circuits, for pedal use that each feed a 700W class D module. It's quite the thing.

[eschertron]

makes me think of Ray Wylie Hubbard's Snake Farm. It just sounds nasty.

nosaj

Well, I guess there's no better time than a Friday night to fall into a previously undiscovered oevre filled with greasy swamp boogie. Thanks, Jason!

[nosaj]

Well, I guess there's no better time than a Friday night to fall into a previously undiscovered oevre filled with greasy swamp boogie. Thanks, Jason!

Tell me what you think of him. I like his music a lot.
nosaj

[nosaj]

Tell me what you think of him. I like his music a lot.
nosaj

Also Ry Cooder is good and for something different try Honky (bassist from Butthole Surfers)
nosaj

[eschertron]

Tell me what you think of him. I like his music a lot.
nosaj

I like the 'cleverness' of his songs. There's a great deal of songwriters who simply drape the lyric over a music bed; here I get the sense of stylistic unity, it feels sincere. And regardless of the band lineup, he's got a great groove!

Also Ry Cooder is good and for something different try Honky (bassist from Butthole Surfers)
nosaj

Ry has been around, I probably need to catch up on what he's done in the last 30+ years
Honky? OK, down the rabbit hole again...

[TimmyP1955]

Here is the Engl E530 preamp straight into an interface.
https://www.youtube.com/watch?v=7YjGal6ABqg
https://www.youtube.com/watch?v=-lKlcymOgb4



More traditional marshall tones don't fair as well but they certainly aren't bad when the PI/PA are omitted

JVM: https://www.youtube.com/watch?v=o1bBYv-7pPE
DSL: https://www.youtube.com/watch?v=CuaZxmf_ddM

D module. It's quite the thing.

I like 530 #1, though only the Marshall with the green box sounds bad.