'All tube' may not mean all tube...

MilwMark

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Please list amps the manufacturer describes as “all tube” that have SS or digital gain stages.
If an amp has tubes, what is wrong with referring to it as a “tube amp”?

The thread premise is that manufacturers list amps as “all tube” but aren’t. What is that premise based on? I’d love for OP to answer my Q above.
 
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printer2

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First let me say that my understanding of how electricity works is not that far removed from how home household plumbing systems work...so anyone who wants to jump in here, please do!

But my understanding is that those 5Y3 tubes in my amps had current flow and efficiency limits, and when some super badass thing I had just played demanded a big macho jolt of current to reproduce the ass-kicking waveform at the speaker, the tube rectifier could get taxed and “lag” a perceptible amount in delivering the rectified current the circuit was asking for. Whereas the SS rectifier just delivered with no perceptible lag.

And despite that, with that particular amp I liked the saggier response better.
Oh, you mean the sag. Sure, just put a sag resistor in with the SS diodes. Done that many times.
 

Powdog

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I love and build tube amps but agree with everything said above. It’s totally subjective. If SS sounds better to your ears then power to you. Tube amps, especially vintage ones are a PITA. Filter caps, carbon resistors, tubes. Personally I don’t care for SS guitar amps. Any effect or gain feature just sounds like a bad MP3 file. Very fatiguing to my old ears. And the whole “single tube” in an otherwise SS amp is complete BS. Just a marketing trick. No one has figured out how to emulate tube distortion.
 

printer2

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If an amp has tubes, what is wilting with referring to it as a “tube amp”?

The thread premise is that manufacturers list amps as “all tube” but aren’t. What is that premise based on? I’d love for OP to answer my Q above.

Classic Vox Tone in a Compact All-tube Amp​


From chimey cleans to classic Top-Boost-style crunch, the AC10C1 delivers all-tube tones with legendary Vox panache!

Finally, you can have the sought-after Vox Top Boost tone in an all-tube and affordable combination.

It does say that it has SS reverb, it has a LND150 Mosfet on the input stage as well as the effect loop.

hbgftHa.png


Mind you, this is not the original AC-10 circuit of the 60's. Given a pair of 12AX7's they chose to put them where they make the most sense. The more I look at it the more I am thinking of copying the first stage rather than just using a pair of tubes alone.
 

printer2

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I love and build tube amps but agree with everything said above. It’s totally subjective. If SS sounds better to your ears then power to you. Tube amps, especially vintage ones are a PITA. Filter caps, carbon resistors, tubes. Personally I don’t care for SS guitar amps. Any effect or gain feature just sounds like a bad MP3 file. Very fatiguing to my old ears. And the whole “single tube” in an otherwise SS amp is complete BS. Just a marketing trick. No one has figured out how to emulate tube distortion.
Actually you are wrong about someone not figuring out how to emulate tube distortion, a Russian fella did a good job from what I heard. Mind you the circuit never made it into production equipment, might be because it runs at high tube like voltages. With two 12AX7's you can get a decent tube sound.
 

Kev-wilson

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Am I correct in recalling that at least some of the Vox modeling amps used a 12AX7 after the modeling preamp as a tiny power tube, imparting some kind of power stage compression/non-linearity mojo, which was then amplified to speaker-driving levels by a SS power amp?

If so, to me that seems like a cool way to get some real “reminiscent of a tube amp” feel with a single preamp tube. But I may have that wrong, and my playing time on those Voxes is almost nil anyway.
I had an AD30VT that worked as you described, I'm no connoisseur but I found it a quite poor sounding amp that did the high gain models better than the cleaner ones, not helped by poor onboard effects and the attenuator dial on the back removes most of what fun there is in the first place.
 

Powdog

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Actually you are wrong about someone not figuring out how to emulate tube distortion, a Russian fella did a good job from what I heard. Mind you the circuit never made it into production equipment, might be because it runs at high tube like voltages. With two 12AX7's you can get a decent tube sound.
I read somewhere two guys figured out how to create a nuclear fusion reaction in their kitchen but I’ve never seen it. Being silly to make a point: I’ve never personally experienced a SS gain circuit that sounded like a tube. And I didn’t mean to infer that you can’t get a decent sound from a Marshall Valvestate. The gain circuit just doesn’t sound anything like a JTM45 (100% tube).
 

wabashslim

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Am I correct in recalling that at least some of the Vox modeling amps used a 12AX7 after the modeling preamp as a tiny power tube, imparting some kind of power stage compression/non-linearity mojo, which was then amplified to speaker-driving levels by a SS power amp?

That tube was in there purely for marketing. I had a first-gen Valvetronix and it was the most digital-sounding POS ever - worse than the first POD. Poorly designed anti-aliasing filtering that they tried to mask by cutting off the normally life-giving upper mids & sparkle...but that couldn't kill the annoying peakiness of the filters. The tube, while technically in the circuit, did nothing useful except to sell the thing. I tried changing that tube as well as the speaker...some difference but no improvement.
I don't know about the later V-tronix with the metal grill. They might be better.
 

printer2

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I read somewhere two guys figured out how to create a nuclear fusion reaction in their kitchen but I’ve never seen it. Being silly to make a point: I’ve never personally experienced a SS gain circuit that sounded like a tube. And I didn’t mean to infer that you can’t get a decent sound from a Marshall Valvestate. The gain circuit just doesn’t sound anything like a JTM45 (100% tube).




 

archetype

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Fender's marketing for the Super Champ XD boasted a 12AX7 as a preamp tube. Technically it's a preamp tube (it's before the power stage in the circuit), but practically it's not because the preamp on these amps is a sound engine microprocessor (100% digital modeling). The 12AX7 tube is a phase inverter for the pair of 6V6 power tubes.

Yes. Specifically, one triode for the driver, one triode for the PI.
 

TC 57

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Please list amps the manufacturer describes as “all tube” that have SS or digital gain stages.
the AC10 C1 (as I own one),AC30 S1, I believe, though not certain, the lower priced Marshalls and Blackstar amps have always made use of tube/SS circuits..I'm sure there's more
 

TC 57

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Classic Vox Tone in a Compact All-tube Amp​


From chimey cleans to classic Top-Boost-style crunch, the AC10C1 delivers all-tube tones with legendary Vox panache!

Finally, you can have the sought-after Vox Top Boost tone in an all-tube and affordable combination.

It does say that it has SS reverb, it has a LND150 Mosfet on the input stage as well as the effect loop.

hbgftHa.png


Mind you, this is not the original AC-10 circuit of the 60's. Given a pair of 12AX7's they chose to put them where they make the most sense. The more I look at it the more I am thinking of copying the first stage rather than just using a pair of tubes alone.
OK, The Chinese made AC10 C1 does not have effects loop...the AC30 S1, which is a scaled up version of this, does...
 

TC 57

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I love and build tube amps but agree with everything said above. It’s totally subjective. If SS sounds better to your ears then power to you. Tube amps, especially vintage ones are a PITA. Filter caps, carbon resistors, tubes. Personally I don’t care for SS guitar amps. Any effect or gain feature just sounds like a bad MP3 file. Very fatiguing to my old ears. And the whole “single tube” in an otherwise SS amp is complete BS. Just a marketing trick. No one has figured out how to emulate tube distortion.
The Tone King Imperial is superb...as are a few other boutique brands ...but they come at a price
 




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