what tube for a less bright univalve?

[SF audio]

Just got one of these - very cool amp, however with the stock EL34 it's a little bright and the distortion is a bit fuzzy for my tastes. What power tube works well for a darker, less fuzzy sound? and preamp tubes, for that matter?

 

thanks

[Bbach1]

You might post this to the ask miles sticky thread on top. Tubes are a deep subject and swapping them out could require some adjustments to the bias so look into it in depth before making any changes.

[Gifthorse]

I would go to the THD Univalve forum. You can learn alot.

 

But if you are looking for a less harsh distortion that will come from changing the first preamp tube to something lower output.

 

When I got my Bivalve it had EL34s and 2 12AX7s. It got massive distortion. I swapped the left preamp tube for a 12AT7 (I think it is 60% of a 12AX7). Anyways, supposedly using a weaker preamp tube in that position makes so it has more powertube distortion and less preamp gain. It made mine more rounded, less harsh, more punchy than crunchy.

[MILLO]

Judging from the THD audioclips page, it seems like I'd love to get a Uni and fit it w/ a 6CA7. Supposedly these tubes are in the EL34 family, but they tend to produce a "darker" sound.

 

Preamp tubes are cheap, so you can experiment w/ a bit more ease on this side, I'd guess. Why not trying those Ruby 12ax7's? I've heard people say the JJ's are dark-sounding, too.

 

 

Tsup, Gifthorse?

[Gifthorse]

Hey dude

 

I haven't experimented with preamp tubes much.

 

I think they are as important or more important than the power tubes as far as shaping the tone.

 

I think E34L's would be my choice for power tubes. For pre I would have to experiment with a few to get the perfect combo. I lost my BEST one!! I don't even know what kind it was other than an AT7.

 

I haven't experimented enough with my amp. When I play through it now it doesn't feel right cuz I am so used to acoustic. If I spent a couple hours playing through it I would fall in love with it all over again though cuz of how perfect it sounds to me.

[picker]

The Univalve is supposed to take power tube changes without needing bias adjustments, primairly becase there is only one power tube. Biasing is to make the tubes work together properly.

That being said, try a 6V6 power tube. They tend to get darker as you push them into distortion.

[BillWelcome Home Studios]

I'm moving, so all of my stuff is packed. But here is a short quote from a message from long ago about this... by the way, if you go into the Ask Myles thread, you'll find a lot of THD info.

/////////////////////////////////////////

 

Myles suggested I start a thread giving my impressions of these tubes for other UniValve owners to comment on... as well as anyone who might want to experiment with their own amps and tubes.

 

So, as a starting point, here's what the kit contained...

 

- 6V6 NOS Mazda

- 6V6 Electro Harmonix

- 6L6 Chinese (Ruby Tubes)

- 6L6 JJ

- EL-34 Svetlana

- EL 34 JJ

- EL 34 Chinese

- 6550 Coke bottle

- KT-66 GEC tooling copy

- KT-88C

 

So far I've spent a few hours each with 4 of the tubes, the KT-66, the 6V6 NOS Mazda, the 6L6 JJ and the EL-34 Svetlana.

 

Here are my first thoughts...

 

- KT-66. The first thing you notice is that this is a BIG TUBE. The UniValve has a cover that easily comes off to change tubes, but this tube is so large and tall that the cover can't be used at the same time... no problem in the studio... not suggested for playing out! The sound of this tube is very solid and clean. I easily got great blues and jazz rhythm sounds from the low input of the amp... with plenty of headroom. This was also one of the loudest tubes I have tried so far. For clean chord comping... this is one I'll often use.

 

- 6V6 NOS Mazda. The first impression of this tube is the opposite of the KT-66. It's the smallest of the tubes in the kit. But the size has nothing to do with its "big" sound. I'm a "blues-rock" player and this tube seems perfect for that style. The notes "sing" at overdriven levels and have a nice and musical "bloom" with no harshness. It doesn't have anywhere near the headroom of the KT-66, but it did sound great on the low power input, with the input level cranked. It's that harmonically rich "clean but just starting to break up" sound that is VERY responsive to pick attack and guitar volume changes. For the sound I'm going for, THIS tube could be the one I use most. VERY COOL.

 

- 6L6 JJ. Since I had a couple of 6L6's I had liberated from my HR Deluxe, I thought I would already know how this tube would sound. But I was pleased to find that even tubes that are similar in name each have their own subtle personality. Like the other 6L6's I have you get a classic "Fender" vibe. On the low input it's blackface clean sounds, with articulate chords where you can hear each string, and bluesy lead sounds. On the high input, you get a sweet overdrive that cleans up with a softer pick attack and lower guitar volume. If I want to "emulate" how my HR Deluxe sounds, (only better), this is the family of tube to use. This one seemed to break up a little faster than my other 6L6's and I found I liked the treble backed off a bit more at higher volumes. Very musical tube.

 

- EL-34 Svetlana. This tube has more of the "Marshall" vibe in its sound. IMHO it's best when cranked for more of a rock, chunk, roar sorta sound. On the low input it was a little spikier, more trebly, not as smooth as some of the other tubes. I don't think I'd use this for jazz much. But overdriven, it SINGS. I can easily get the "good feedback" happening, and it really liked my humbucker guitars a bit more than the single coil ones. When cranked, it doesn't clean up as well as the others when I lowered the guitar volume... but that could be cool for rock songs where you want to keep the grind, at lower volumes than you would solo at...

 

Well, I don't want this to be a novel, so I'll end it here. If you have any questions about any of these, let me know. I'll give you my input... And as I try out the other tubes, I'll add to this post.

 

guitplayer

--------------------------------------------------------------------------------

 

guitplayer...

 

First off ... you sort of "stole" that kit! I had the reserve way too low. I have other kits now that are similar, but raised the reserve two times over what it was on your kit, and it has one less tube.

 

By the way ... when "old" tubes that are worn out and not matched, don't toss them anymore, they work GREAT in the Univalve.

 

On the KT-66 ... when I use these, I just leave off the cover. Then the amp looks sort of like a vintage McIntosh. Turn off the lights and look at the "blue glow" when you turn on the B+ (standby OFF). It is a very linear tube, more so than any 6L6. The KT stands for "kinkless tetrode" and was developed to get rid of the kink in the curve of 5881's and 6L6's. It has more body in the mids and lows without having them just be louder.

 

The NOS Mazda is perhaps one of the ultimate blues tubes of all time. They are great in Fender Deluxes too. My most used Univalve or GT Single config is a 12AX7 in V1, 12AT7 in V2, and the 6V6 as the power tube. These are super articulate and touch sensitive. They are even more amazing in the GT Single, as the Single runs higher plate voltages (and will eat up 6V6's faster), and has an output transformer about twice the size of the THD's. Like in cars where "there is no subsitute for cubic inches", in amp transformers, "there is no subsitute for iron". A great tube in either amp!

 

6L6 JJ. Think of this as something of a cross between an strong 6L6 and an EL34. More mids and highs than most EL-34's. I have a lot of clients that play hard rock with Fender Twins and Showmans that love this tube.

 

EL-34 Svetlana. Your's is of the date codes prior to the problems of the recent Svets, so this is a good example. Wait until you try the E34Ls and the EL-34C ... you will see how different EL-34's can be!

 

The EL-34C is my favorite 25 watt EL-34 in the Univalve, GT Single, and in JCM 800 and earlier Marshalls, or Rivera amps.

 

Happy playing !

 

--------------------

Myles S. Rose

[mdrs]

The THD Univalve amp sounds fasinating. To be able to easily swap out tubes, and evaluate their different tones in one rig sounds like a great chance for a "tube education". I've always heard talk of how one tube sounds a certain way, while another tube is distinctly different sonically. The THD Univalve sounds like a great platform to explore this with.

 

I think I HAVE TO GET ONE!!

 

Serious question....where do you get these tubes you guys are discussing? If one wanted to really test the waters, what group of tubes should I get?

[BillWelcome Home Studios]

Originally posted by mdrs:

...Serious question....where do you get these tubes you guys are discussing? If one wanted to really test the waters, what group of tubes should I get?

Myles is the best soiurce for guitar amp tube info that I have ever seen. He will point you towards numerous sources of NOS and new tubes, of all different types, and he has tried most of them and knows how to describe to you the differences among them. (And it is amazing the different sound that one gets from the same tube, from a different manufacturer, or even manufacturing batch.) I bought a handful of Groove Tubes, and I got some Mesas (which are Groove Tubes, rebadged), and I got some real vintage tubes from an electrician tech for Korby Audio (a boutique vintage style mic manufacturer). But there are guys on the web who sell the real deal. Warning.. though some tubes are as little as under $10, many of the more affordable vintage NOSes are in the $55 range, and some are $85 to $125 or even more.

 

The key to keeping the costs in line is to know what sound you are after, and describe it to Myles. Then try out his suggestions, a couple at a time. It is a bracketing process... aim, fire, adjust left; aim, fire, raise elevation; aim, fire, etc, etc. It only took me a couple of tries, but I started out by passing on the hard to get and over $40 tubes, and I knew what I wanted to hear.

 

Bill

[mdrs]

Thanks, Bill. I've been interested in the THD, particularly after you mentioned that you sold your vintage amps off after getting one! The prospect of exploring the sonic properties of different tubes has also caught my interest.

 

Now, should I buy one on eBay or a new one?? I did notice that many sold on eBay are going with extra tubes included.

 

Decisions, Decisions!!

[BillWelcome Home Studios]

Originally posted by mdrs:

Now, should I buy one on eBay or a new one?? I did notice that many sold on eBay are going with extra tubes included.

 

Decisions, Decisions!!

That is always the question, isn't it?

 

Well, if someone is offering the tubes that you want to try, then ebay may be the way to go.

 

I do want to caution you... I still say that if you really want a 1959 Deluxe or somesuch, then that is what you should buy. Just because I sold my own amp collection, that does not mean that you will be so enthralled with the THD as I was. I got the sound that I wanted, not an exact copy of any vintage amp sound. This was not my intention.

 

Bill

[mdrs]

I'm with you Bill. I LOVE my old amps, and would not consider parting with any at this point. But, your having done so speaks loudly about the quality of the THD.

[miroslav]

I saw a Univalve on eBay last night with a $650 BIN price...(if it's still there).

[Gifthorse]

Excellent commentary Bill. I have to try a 66. I tried KT 77's and I thought they were a little too much low end for me. So far I like the ruby 6L6 and EL 34. I haven't actually tried an E34L but they sound exactly like what I want. They have more clean headroom.

 

 

I would get it on Ebay or Craigslist locally if you have one Don.

 

I mean it is the kind of amp, I believe, most people wouldn't throw around.. It would attract a serious player who cared. No worries there. When I was looking I saw Univalves going for pretty cheap. Like $600 with tubes used and even cheaper. The cheapest one I saw was $500.

 

I think it is a good idea actually if you can get it with tubes. Find out why the guy is getting rid of it of course. Also what kind of cabinet are you going to use?

 

God I know I never shut up about it but I can't wait to hear my Bivalve through a 4/12. Holy shitballs..

 

Funkjazz bought one cuz I was going sick about em, and he is blown away completely just like I am. Its pretty undeniable. Good luck not becoming a tube geek. You will be on the phone with your friends and to other people you will sound like your from another planet.

[mdrs]

Cool, Flag!! I have a couple of Marshall 4x12 cabs, each with different speaker in them. I also have a Reeves 4x12, which has fane speakers that stays remarkable clean even played loud. I also have a Cornford 2x12 with Vin. 30s, and a Rivera 4x10. So, I'll have a bunch of cabs to choose from and see which on the amp "likes".

 

I always felt most like a "guitaraholic", but I guess anything that can become a "facilitator of tone" is something I'm keenly interested in. So, maybe it's tube time.....

[BillWelcome Home Studios]

Originally posted by mdrs:

I always felt most like a "guitaraholic", but I guess anything that can become a "facilitator of tone" is something I'm keenly interested in. So, maybe it's tube time.....

Yeah, and then you'll start to be disatisfied with your effects, and make the jump to Fulltone, Keeley, Teese, analogman, etc. I kmow that I did. I was perfectly satisfied, in an 'ittlldo' way, with my multieffects units until I got the boutique amps. (sigh....)

 

Bill

[mdrs]

The never ending quest.........

 

It's an interesting road.

[Gifthorse]

I have a feeling it will give you what you want. God if I had a great tube collection I think I would lock myself in a room (naked) with my bivalve.

 

Heh, always the clowns. As if using the plural works...

[mdrs]

I bought one on eBay. It comes with;

 

groove tubes 6L6, groove tubes kt66, westinghouse japan 6v6gta, EH 12ax7, USA black plate (rca) 12au7, marshall ecc83, GT 12at7, mesa spax7.

 

So, I'll have a beginners' Primer on tube tone soon!

[Gifthorse]

Killer dude. I am jacked for you. I was only kiddin about the naked thing. Don't get carried away!!

 

Don't forget about El34's.

 

Since your a doctor you can go sick with the tubes cuz you are worth MILLIONS upon MILLIONS. Just don't order any boob tubes.. God, that sucked but I had to go with the flow. I think I even sent Myles a message that said my girlfriend needed some new tubes or something. Whatever, its all chicken eggin me out. But there is nothing wrong with that. OK, getting kind of early, I better hit the hay.

[MILLO]

Don't forget to try JJ Electronics KT77 output tube. Or KT 88 for that matter.

 

Someone who had the BiValve here in Austin told me he loved the KT88 along w/ an EL84.

[Gifthorse]

My buddy in Portland has all of them.

 

When you get it you will be a free man with all those tubes. You can run free and make up your tone as you go along. Not a bad idea. I am going to my singers now to check out my new free tubes. Then I will come back and post a huge long thing about how great the Bivalve is and how Lee would love it. Anyways, I gotta go. The coffee is kickin I am going to go rake the kitchen or something.

[mdrs]

I got my THD Univalve and cranked it up today. I started with a Marshall ECC 83 in the "input", and a Groove Tube GT12AT in the "driver". The first power tube I put in was a Groove Tube GT-KT 66.

 

WOW!! Think touch sensitive Marshall Plexi.....and powerful. It really liked my Rivera 4x10 cab. This Amp ROCKS....and boy is it loud! I'll be using my ear plugs playing this for sure.

 

You can hear every nuance of your string attack on this amp, and you can go from very funky touch sensitive with your guitar volume down, to "rip you a new one" with the guitar volume up. It really was exhilarating to play this amp!!

 

The power attenuator, which is built into this amp, is the best I've heard to date. It does save the ears, yet allows the tone to come thru.

 

I've got two more power tubes to check out, and a couple of pre amp tubes. I also want to get a NOS Mazda 6V6 to check out.

 

I'm not going to sell off my "wall" of vintage amps. But, after playing this thing, I can certainly understand why one might!

 

This is an outstanding amp! If you can check out a Rivera 4x10 speaker cab. It really helps deliver your sound clearly, with excellent articulation.

[MILLO]

I'm DEFINITELY getting a Univalve in Jan. or Feb. And a few power tubes! I'm pumped!

 

mdrs: What speakers does the Rivera cab have?

Which other cabs did you like w/ it? I guess it'd depend on what tubes are in there.

[mdrs]

I only played it for a couple of hours tonight....the time just flew by...I was hypnotized by this amp!!

 

I played it thru a Marshall TV 4x12 cab, and it sounded very deep and dark and more distorted...it really had balls!

 

I preferred it thru my Rivera 4x10...I'm not sure what speakers come in the Rivera. I think they are Celestions, but the have a plain black coating on the back of the speaker. I checked on their web site, but could not find out for sure what speakers are in it. But, it enhanced the tone, but keep things clearer....what I mean is that the pleasing distorted tone was maintained, but the Rivera made it easier to hear all of the notes I was playing. It kept the sound less mushy.

 

I did find a "factory blowout" sale of a 4x10 speaker cab for $300 bucks.....if it's the same one I have, that's a pretty good deal;

 

http://www.rivera.com/sale.php

 

I FOUND OUT THAT MY RIVERA 4X10 IS A C410 SPEAKER CAB WITH EMINANCE SPEAKERS.

[BillWelcome Home Studios]

Originally posted by mdrs:

I only played it for a couple of hours tonight....the time just flew by...I was hypnotized by this amp!!

 

When I still had the studio, I had found the tube combo that worked in the UniValve for me, and I was sitting with a Fulltone Deja2, a Fulltone Clyde, and the smallest bit of distortion from a Reverend DriveTrain, and I just got lost in it. I was playing the Gibson 336 with the new Duncan Fat Cat P-90 humbucker replacement size pickups. A client showed up at the door, let himself in, and said how he didn't want to bother me while I was "channeling Hendrix". Like you, I found the amp exhilarating, and it was easy to get lost, as everything sounded so good when I found the right tubes.

 

According to most everyone who follows these things, the power attenuator, though not bad, is not 'the best'. I think that the Dr Z AirBrake might be the one that seems to have the least impact on the tone. But the THD seems to be the next choice, so we didn't do too baddly in getting one included in the price of the amp, since it runs close to $300 on its own.

 

Bill

[Gifthorse]

You know, it is hard to compare them really. I mean I think the attenuator on the Bivalve is PERFECT for the amp.

 

My singer had an Airbrake. It worked, it has more controls than the one on the Bivalve. I wouldn't say it is better. I think that and the Hotplate just have more parameters. So much of how it will sound depends on your amp. I think it works alot better on lower wattaged amps.

 

The airbrake through the VHT Pitbull 45 was pretty cool, but at 45 watts it was still almost too loud. I mean you had to crank it up to make it sound good. It did knock off some volume though. Myles told my other guitarist to forget about using one on his Fender twin reissue which is 85 watts.