THD Univalve ....... Good, bad or ugly ?

[Dr. Tweedbucket]

My thoughts on buying one of these are, it would be cool for testing out different tube, guitar pickup and guitar tone characteristics. Too, it could make a cool bedroom amp. Supposedly it is very transparent and will reveal subtle differences between different tubes or guitars.

But! ..... I read mixed reviews on this amp ..... it seemed to be either a love / hate thing. Any users or opinions here?

 

[vchizzle]

Great.
It being single ended class A, people don't expect it to sound the way it does maybe? It doesn't like V30 speakers and sounds better with open back cabs. I think its a very pure tone.

 

[BIGGERSTAFF]

I don't own one, but have played them, and listened to others playing them on a number of occasions. I think they sound great, and are a great deal at their selling price. If you don't need super high levels of clean headroom, they're easily giggable in small clubs.

 

[sampleinajar]

I own one and will keep it, but it is very finicky. It is astonishing how it can sound like the worst amp ever with certain combinations of tubes, guitar, and speakers, and then the next minute sound like the greatest amp, hands down, that I have ever heard with other combinations. My personal experience is that it likes humbuckers better than single coils, and that it lacks a little low-end response that can be compensated for by proper speaker and cabinet choices. The built in attenuator is useless (Sorry Ed and Andy), and you'll never be happy with bedroom level tones out of this amp. Just don't go there. It sounds best with the volume between 1-5 o'clock (dimed). If you need any amount of clean headroom, just forget it in terms of gigging. Distorted lead and rhythm tones are where it shines.

All MHO, of course. It is a cool amp, and i have had mine for 5+ years.

I could see going with a two amp A/B set-up for clean tones with a Fender or JTM-45, and lead tones with the Uni.

Steve

PS - Ed, if you're listening, I think a stripped down Uni with no attenuator, and no line-out would be killer. Maybe add a mid-control, and your talking a killer amp.

 

[dumeril7]

I had one. Overall, it was a great amp but not a good fit for my purposes. Gain-wise, I thought it was at its best as a hard rock or old-school metal amp. Yes, you can swap tubes for lower gain, but I always felt that it didn't sound as good that way. To my ears, there was a character to the upper harmonics when overdriven that really worked well for hard rock, but not so much for warmer vintage tones. (And yes, I did a whole lot of experimentation with tubes to see if I could change that.) sampleinajar's comments about its low-end response and clean headroom were right on the money IMO. Don't buy this amp thinking you'll be able to quietly play with great tone in an apartment at midnight. It is, however, a whole lot quieter cranked up than anything rated 18W or more. If you buy it with the intent of rocking out at reasonable volumes, I can't imagine not being happy with it. It would also be cool in a multi-amp setup as the lead voice IMO; you could get that cranked tone at a comparable level to other amps running clean or crunchy.

D7

 

[Natron]

I had one. Just note that while switching tubes will change the sound of the amp, it won't change the sound of the amp enough to sound like other amps. It'll just sound like a different variation of what a Univalve sounds like. If you buy one thinking you'll have a "Marshall Plexi" set of tubes and a "Fender Tremolux" set of tubes you can simply swap back and forth, you'll be disappointed. It sounds like a Univalve, period.

It was a great amp but didn't work for what I wanted at the time. These days, I would consider buying one again since I use some lower-gain tones at times. When dimed and running full power tube distortion, be ready for the sound to be loose as a goose. It's not very tight at that point, obviously, since the power tube is running right on the ragged edge of its limits.

If I could squeeze more gain out of it with a boost pedal or something and not have the response be so loose, I would pick another one up immediately.

 

[Dr. Tweedbucket]

That's a lot of good information, thanks. Half of my interest is in hearing differences if I swap from an EL34 to a 6L6 to a KT88..... or swapping a Sovtek 12AX7 out for a Mullard ECC83 to hear the difference.

Also, as long as I can get some decent tone out of it in just playing it, or recording with it, I'll be happy.

Maybe some of the poor reviews I read was from guys who just didn't get the right combo of guitar / tubes or speakers dialed in.

 

[dumeril7]

Half of my interest is in hearing differences if I swap from an EL34 to a 6L6 to a KT88..... or swapping a Sovtek 12AX7 out for a Mullard ECC83 to hear the difference.

It'll be good for that. But what I think you'll learn is that an amp's sound is the result of a system of components, not any single one. As Natron said, tubes will nudge an amp in one direction or another, but the effect isn't earth-shatteringly dramatic.

Maybe some of the poor reviews I read was from guys who just didn't get the right combo of guitar / tubes or speakers dialed in.

No, I don't think that's it. There must be some for whom that's the reason, but I think its mostly people who just didn't like the core sound of the Univalve and nudging it in one direction or another by changing tubes (or speakers) didn't change it from being a Univalve. It didn't for me anyway. That said, if you dig the basic character of the amp, nudging it to emphasize or deemphasize certain qualities will be very rewarding IMO.

D7

 

[Dr. Tweedbucket]

It'll be good for that. But what I think you'll learn is that an amp's sound is the result of a system of components, not any single one. As Natron said, tubes will nudge an amp in one direction or another, but the effect isn't earth-shatteringly dramatic.

No, I don't think that's it. There must be some for whom that's the reason, but I think its mostly people who just didn't like the core sound of the Univalve and nudging it in one direction or another by changing tubes (or speakers) didn't change it from being a Univalve. It didn't for me anyway. That said, if you dig the basic character of the amp, nudging it to emphasize or deemphasize certain qualities will be very rewarding IMO.

D7

Makes sense.

Have you ever compared one to an Orange Tiny Terror?

 

[GCDEF]

That's a lot of good information, thanks. Half of my interest is in hearing differences if I swap from an EL34 to a 6L6 to a KT88..... or swapping a Sovtek 12AX7 out for a Mullard ECC83 to hear the difference.

Okay. so you do that for an hour or two. Then what? You're stuck with an amp with very limited practical application.

 

[Jon Silberman]

I owned one for 3 months before selling it. It got my vote for worst amp disappointment ever in the long thread to that effect that was ongoing here a while back. Then again, I've heard clips of Ed DeGenaro, I believe it was, playing though one and it sounded like the voice of angels. So I think it's a very idiosyncratic call on that particular amp. To be fair to it, it's not your father's "old design" and shouldn't be judged that way (as, in retrospect, perhaps I unfairly did). Still, wouldn't ever buy another for myself.

 

[myles111]

Best "distortion pedal" out there.

Set up the amp with nothing connected to the speaker jack (yes, it is safe and fine on the UV).

Run a cable of the line out at instrument level using a regular guitar cord to the input of a clean amp. Turn the UV all the way up using a 6V6 or EL84 in their adaptor and crank it. Adjust the UV output level using it's level control on the back panel as to not overdrive (unless that is your desire and taste) the front end of the main amp.

Dial in the degree of agression you prefer and have the big clean amp project your tone.

Even better with a Twin Reverb but with these Pro Tube Series that have a nice clean side but an awful distortion side (for my taste) the UniValve can be a great tool.

 

[Dr. Tweedbucket]

Okay. so you do that for an hour or two. Then what? You're stuck with an amp with very limited practical application.

I think it has potential. If I get tired of it, I'll plug into some other amp that's sitting around.

 

[Gigbag]

I've had my Univalve for 5 years and don't see getting rid of it.

Pros:

• Great for experimenting with tubes. Learn about tubes (pre and power), and put in tubes with 2 to 3 watt output for low volume (better than attenuation).
• Can be morphed into a wide range of tones with tube and speaker swaps.
• Has its owne unique sound.
• Is a favorite distortion box (as noted above).
• Very well built.
• With tinkering (setting knobs much different than unattenuated) you can get good low volume tones (not the same as full volume).
• Great line out (intrument or line level, and output level controls).
• Built-in dummy load (which is great for DI or use as distortion box).
• Heavenly response and tones unattenuated.
• Looks cool.
• Great customer service from THD.
• Compact size.
• The qualities of your guitars will show (for better or worse).

Cons:

• Attenuation is not a magic pill for whisper quiet stage volumes.
• Could use more clean headroom.
• No effects loop (but Bi-valve has one).
• Can be bright with certain tubes/speakers.
• Tone controls do not work the same as common amps, which may confuse people who don't get used to them -- often resulting in bad reviews.
• It will not let you get by with sloppy technique (which is a plus as it forced me to be less sloppy) like some amps do.

 

[Glass Onion]

I love mine and have for a few years now. It is picky and some days sounds right horrible. Other days it is the best of the best. I use mine out live but do not have a heavy hitting drummer. I also have a custom vibrolux for clean. Get it and play it. It should be alot of fun.

 

[vchizzle]

For your application I think it will be great. That's what it did best for me. If you have an array of good tubes, they do make a difference. I think you can change the sound of the amp ALOT with the tube swaps. I've had 2 of these amps and am certain I have another someday. RCA blackplate 6L6's or 6V6's yield incredible clean tones. To me it was very noticeable from the garden variety 6L6. I liked the 6V6 in it the best great clean or dirty tones. KT-77's sound great for overdriven stuff. Preamp tubes and different combos of them make a difference too. I spent a long, long time tube swapping. You can certainly find bad combos, but there are some that when you find it, you won't wanna try anything else for awhile.

The Rock and Roll inputs make a huge difference between clean and dirty tone. To me the THD cab makes it sound glorious. There's a THD forum, not super active, but lots of good reading there. If I find it I'll let ya know.

 

[vchizzle]

here you go: http://www.univalve.net/

 

[Jerrod]

Okay. so you do that for an hour or two. Then what? You're stuck with an amp with very limited practical application.

Limited? If it works, it works. It obviously didn't for you, and you got rid of it. For others it works great.

 

[stump]

I've had mine for a couple of years now and still enjoy it regularly. I grab cheap single tubes at Flea Markets and yard sales and get a wide variety of tones. Like others said the attenuator is not great and the amp definitely has it's own character. I like the ability to get unique tones from it as well as it being real responsive. It's a hell of a lot of fun IMHO.

 

[[email protected] C]

For something in the same ballpark but with potentially more usablility, you may wanna check out the Univalve's brother, the BiValve. Same basic design, but with more "oomph" @ 30 watts plus a nice FX loop. Not as bright as the UniValve, but with more bottom end.

I've spent a lot of time swapping tubes in mine, and yes, you can hear a difference. It's not earth shaking, but it certainly does change how the amp sounds. I look at it as being able to fine tune the amp- it still sounds like a THD, but you can flavor the tone a bit.

The attenuator is ok, as other have stated, but certainly usable for gigging. I've used mine in everything from worship services to outdoor gigs to small clubs, and I've been able to dial in a volume that works without killing the tone. Not really good for bedroom levels though.

Great, well built/ engineered amps- YMMV though!