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Tube Preamp for Benchmark AHB2 or Class D/SS Poweramp?

It's a fairly dumb thing to do, but one thing no one has mentioned yet. Tube preamps like to drive tube power amps because they have high input impedance. Solid state power amps have much lower input impedance than tube power amps. And tube preamps have higher output impedance than solid state preamps. So you could end up with an impedance miss match.
 
Seems like a terrible waste of an AHB2. You could maybe try a SET amp if you want fuzzy stuff.
+1 :cool:

I use one -- mostly driven by a ss preamp of no particular provenance*. Actually, it's not even technically a preamp, much less a stereo preamp -- but don't tell it.





A delightfully fuzzy combination, in my opinion.

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* Actually, I picked it up from the scrap pile at the Grantham NH dump a few years back. :)
 
Schitt Freya Noval (or Freya Plus) does exactly that. I have done this with my JBL 708P and Meyer Sound Amie and I think it's great. The passive attenuator is as good as the APx555 and at least when used for attenuation rather than amplification, the level of distortion in tube mode is not so high to be bad, but high enough to offer some effect to the music. I know someone that uses a Vinnie Rossi 300B pre-amp with their ATC active speaker setup!

If you're based in the US, I'm probably going to sell my Freya Noval if you're interested. Currently I use a Yamaha AVP instead of the Freya Noval since it has one-box simplicity. Just PM me. Just saw that you're in the UK.

 
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Try a pair of these. Expensive at $799 a channel. All tube, transformers (where tube sound is when there is one), and still goes thru transformers and tube with EQ bypassed. Balanced outputs and inputs too. Also has very adjustable EQ so you can definitely monkey with the sound. Recreation of the Pultec tube EQ units.
Great stuff, thanks for the hint! I know the WA preamps from a recording context but hadn't considered putting them into a hifi chain. Still got an old Avalon 737 in storage that I used to use as mic preamp in what feels like a former life. Maybe I'll get a second one and.... ;-)

What do you think of this one? Looks quite flexible in terms of modding options and is reasonably priced...

 
Plus, good tube pre's aren't audible much. Something of a myth as much as anything.
That. You're more likely to get audible distortion from a tube power amp.
 
That's great, so we agree! I acknowledge in my post that tubes would reduce the accuracy of reproduction. Yet, as with mechanic watches, there is more than one subjective / hedonic way to appreciate sound or a time piece...
I fully understand and it’s your prerogative of course to distort or do whatever you want. That’s why I suggested some more cheaper, quicker and adjustable way of doing it, instead of buying one amp after another (besides you probably won’t even hear it).

Look, adding distortion to reproduction is quite common for example for DJs. They take out frequencies, pan, … add all kinds of effects. And this is done for performance (artistic reasons if you like - without starting an argument what art is or not) but it occurs during reproduction of music and has not the objective to accurately reproduce the original recording.
 
+1 :cool:

I use one -- mostly driven by a ss preamp of no particular provenance*. Actually, it's not even technically a preamp, much less a stereo preamp -- but don't tell it.





A delightfully fuzzy combination, in my opinion.

________________
* Actually, I picked it up from the scrap pile at the Grantham NH dump a few years back. :)
Nice... but that's a power amp then, right? And I think a tube power amp that would drive my speakers would be at least $1.5k+?
 
Great stuff, thanks for the hint! I know the WA preamps from a recording context but hadn't considered putting them into a hifi chain. Still got an old Avalon 737 in storage that I used to use as mic preamp in what feels like a former life. Maybe I'll get a second one and.... ;-)

What do you think of this one? Looks quite flexible in terms of modding options and is reasonably priced...

Don't know anything about the one in your link. So hard to say much.

Hey, I remember way back when getting a Conrad-Johnson PV5 as people told me it would get you halfway to a tube sound as I needed a powerful SS amp for my speakers. It was a fine piece of gear. It didn't have much sound really. Later a C-J MV50 tube amp did.

Maybe peruse some of the 2nd hand sites looking for an old C-J or similar. Don't know what they go for these days. Or grab another Avalon 737. ;)
 
That. You're more likely to get audible distortion from a tube power amp.
I've had a look at the Muzishare X7. A Chinese Push/Pull which gets raving reviews in... well... subjective reviews and among tubesters... ;-)
 
I've had a look at the Muzishare X7. A Chinese Push/Pull which gets raving reviews in... well... subjective reviews and among tubesters... ;-)
I'm hardly the one to rate tube amps, being a crabby old engineer. But mhardy6647 can perhaps steer you right...
 
Nice... but that's a power amp then, right? And I think a tube power amp that would drive my speakers would be at least $1.5k+?
Right -- @fpitas and I suggested, flippantly, but I'll opine only partially so, that the AHB2 power amp is a superb performer and merits a superb front end.
If one wants tube sound -- the AHB2 should probably get out of the way.
I don't intend to speak for @fpitas, though, despite the fact that I sometimes wonder if we were separated at birth or something*. ;)

You could (in seriousness) try a "passive preamp" -- in other words, a high quality attenuator** and a source selector (if needed) -- if your "use case" doesn't require additional drive for the power amplifier's line-level input.

In full disclosure, I do sometimes use the above-pictured SE 2A3 amplifier with a passive "front end", also with good results, but the additional drive capability of the Yamaha adds some oompf to the proceedings and has become my de facto standard in the past few years.



____________
* He, however, was seemingly raised by a solid-state tribe, while the tribe that reared me subsisted on tubers. ;)
** I like transformer or autoformer volume controls, but there are very fine ladder-type resistance attenuators, as well.
 
I've had a look at the Muzishare X7. A Chinese Push/Pull which gets raving reviews in... well... subjective reviews and among tubesters... ;-)

I'm hardly the one to rate tube amps, being a crabby old engineer. But mhardy6647 can perhaps steer you right...

umm, yeah, no. actually to both comments ;) -- but the "Muzishare X7" is junk. Sorry. :(
 
Have you played with the EQ and loudness on the RME? You could get different sound signatures by warming it up or adding more presence.

I'm not sure how much "good distortion" you'd get from a preamp stage, but I think some people recommended specific effects for that, which would likely work better than a normal tube preamp.
 
He, however, was seemingly raised by a solid-state tribe, while the tribe that reared me subsisted on tubers. ;)
Not quite. I kept my trusty box of tubes quite late in the game, perhaps 1971, because transistors were so terrible back then. But then I threw them in a lake. Luckily the only valuable tube was a 6SN7, which I'm sure would be placed on some audiophile's pedestal now.
 
I fully understand and it’s your prerogative of course to distort or do whatever you want. That’s why I suggested some more cheaper, quicker and adjustable way of doing it, instead of buying one amp after another (besides you probably won’t even hear it).

Look, adding distortion to reproduction is quite common for example for DJs. They take out frequencies, pan, … add all kinds of effects. And this is done for performance (artistic reasons if you like - without starting an argument what art is or not) but it occurs during reproduction of music and has not the objective to accurately reproduce the original recording.
I'm all for sonic pluralism and believe in meaningful exchange across paradigms. I'll definitely look into the plugins as a kind of dry-run to get an idea of how a tube stage may sound in my setup...

I respect your perspective on the consumption of a musical reproduction as a process in which the listener is the a passive receiver. Just saying there's a school of thought that considers any artistic performance (even reproduction) or really any communicative exchange as an act of active co-creation of meaning between artist and onlooker / listener... Not looking to get into epistemological arguments though. I hope my original post didn't come across like I wanted to convince anyone of anything that goes against their strongly held beliefs.
 
Right -- @fpitas and I suggested, flippantly, but I'll opine only partially so, that the AHB2 power amp is a superb performer and merits a superb front end.
If one wants tube sound -- the AHB2 should probably get out of the way.
I don't intend to speak for @fpitas, though, despite the fact that I sometimes wonder if we were separated at birth or something*. ;)

You could (in seriousness) try a "passive preamp" -- in other words, a high quality attenuator** and a source selector (if needed) -- if your "use case" doesn't require additional drive for the power amplifier's line-level input.

In full disclosure, I do sometimes use the above-pictured SE 2A3 amplifier with a passive "front end", also with good results, but the additional drive capability of the Yamaha adds some oompf to the proceedings and has become my de facto standard in the past few years.



____________
* He, however, was seemingly raised by a solid-state tribe, while the tribe that reared me subsisted on tubers. ;)
** I like transformer or autoformer volume controls, but there are very fine ladder-type resistance attenuators, as well.
AHA! I now have proof you stole my design for solid adjustable shelves for your gear. I made one like that 30 years ago. Only I rounded the corners on the shelf, and eventually painted them in shiny black. Sturdy, relatively inexpensive, infinitely adjustable (though inconvenient to adjust). I also later sheathed the threaded rod in softer material so you wouldn't risk scratching gear as you slid it in or out of a shelf.

Or maybe great minds just think alike.
 
Don't know anything about the one in your link. So hard to say much.

Hey, I remember way back when getting a Conrad-Johnson PV5 as people told me it would get you halfway to a tube sound as I needed a powerful SS amp for my speakers. It was a fine piece of gear. It didn't have much sound really. Later a C-J MV50 tube amp did.

Maybe peruse some of the 2nd hand sites looking for an old C-J or similar. Don't know what they go for these days. Or grab another Avalon 737. ;)
Much appreciated! I'll look into these!

What I like about the MP pre is its simple circuit and the fact that it allows not only tube rolling but also capacitor rolling without soldering... So many ways to abuse that AHB2... :-D

MP-701-MK2_04-1024x683.jpg
 
I'm all for sonic pluralism and believe in meaningful exchange across paradigms. I'll definitely look into the plugins as a kind of dry-run to get an idea of how a tube stage may sound in my setup...

I respect your perspective on the consumption of a musical reproduction as a process in which the listener is the a passive receiver. Just saying there's a school of thought that considers any artistic performance (even reproduction) or really any communicative exchange as an act of active co-creation of meaning between artist and onlooker / listener... Not looking to get into epistemological arguments though. I hope my original post didn't come across like I wanted to convince anyone of anything that goes against their strongly held beliefs.
All good. You made it clear that you don’t want accurate reproduction for your experiments. Enjoy.

Will be fun to play with a DAW. At least I enjoy it too occasionally.
 
Have you played with the EQ and loudness on the RME? You could get different sound signatures by warming it up or adding more presence.

I'm not sure how much "good distortion" you'd get from a preamp stage, but I think some people recommended specific effects for that, which would likely work better than a normal tube preamp.
Yes, played with the EQ and Loudness. Neat features. RME now has a computer/iPad based "remote" app for the ADIs. Full control of the EQ and DSP...
1701299209124.png
 
I don't mean to criticize any of the posters in this thread, but man, what a peculiar discussion.
 
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