Valve Junior v.3 combo and Red Fuzz

[mac]

After 3 month of use, maybe 30 to 50 hours, this little combo is sounding better and better. It is like old new car engines that needed 2500km on the road. The eminence 8"  is sounding a lot better. The initial fizziness above 1/2 drive it's almost gone.
Still needs about 10-20min to warm up. I'm using it up side down.

I'm using  a Red Fuzz ( GGG ) as a kind of tone control and to boost the signal. It filters some low freqs, and the tone control the highs, which is cool when you set the amp above 3/4. The RF volume pot does the rest. I set the RF drive pot near zero.
I normally set the RF tone to the middle, volume at or above unity gain, and drive near zero, and the VJ to 3/4 or full gas. This set up gives a fuzzy, creamy and plastic mid-range sound.
If I want something less fuzzy, a trebly crunch or overdrive, I set the VJ to 1/4 or 2/3, and the RF tone to the high side, and the volume way above unity gain. Or I can use my Rangemaster. Or better, I can turn my Laney LC30 on and rock the whole building

If you have a VJ, I suggest you trying a Red Fuzz, or Rat or Ibanez FatCat. Just change the output fet to a MPF102 or BF245C to get near 4.5v at the source.
I can easily get  "we won't get fooled again" or "money for nothing" or "at the woodchoppers ball (live)" kind of sounds.

BTW, I'm looking for the VJ PCB to build my own clone with better parts, like Hammonds PS and OT. Links anyone?

mac

[.Mike]

BTW, I'm looking for the VJ PCB to build my own clone with better parts, like Hammonds PS and OT. Links anyone?

A lot of people rebuild their Valve Juniors using turret board from, surprisingly enough, TurretBoards.com. I've never ordered from them, but they have a good reputation.

Click the "VJr Stuff" link on the left side. It looks like the turret board with pre-mounted tube sockets is on sale for $33.60 plus shipping.



Mike

[newfish]

Almost related - I've got similar (very pleasing) results from a Behringer AC-108 and a dirty booster pedal.

Single Tranny booster hard-wired for maximum gain (Collector straight to ground with 22uF cap in parrallel) with a single volume control on the output.

Drives the 12AX7 pre-amp beautifully.

Amp has been modded with a 1/4" switching socket to allow connection to a bigger speaker.

Small amps, when given a bit more drive are definately the way forwards.

[m-theory]

http://forums.epiphone.com/Default.aspx?g=posts&t=7
http://www.sewatt.com/node/14462

First off, the red fuzz is a great circuit for any amp.  Haven't quite figured out why it's called a fuzz, but it sounds really good nonetheless. 

Onto the amp...I'm really not much a fan of the stock Vjr tone, even the V3.  I find them to be harsh, buzzy, mushy, and uninspiring in their stock form.  Now, the V3 is marginally better than previous versions, because the output transformer is better suited to an EL84 tube, but most of the basic flaws in the circuit remain from the previous versions. 

At the very least, the output tube is biased FAR out of spec, and should be dialed in.  That change alone (as well as dropping C3 and C4 to between 1uf - 3.3uf, to eliminate bottom end flubbiness) is a marked improvement overall. 

I've had a V2 head since they first came out, and went through every machination of mods known, other than the one that's named for a certain transformer manufacturer, and recently did a turretboard EL34 build.  This is what I should've done long ago.  This amp is now as close to tonal perfection as I believe an SE amp can possibly get. 

On transformers, there's no need to upgrade the PT.  The stock V3 OT is somewhat in between a 125CSE and 125DSE, so unless you're going to an ESE, there's no need to upgrade that, and if you're staying with the el84 tube, there's only marginal improvement in going to the ESE.  You'll need that one if you're going octal, however. 

You won't likely find a PCB for it.  Either upgrade and mod the one you've got or scrap it and do a turret or eyelet board build.  Heed common AC voltage warnings before starting. 

[Theox]

+1 what m-theory said.

Ditch the PC board and go octal with an eyelet board from turrteboards.com and a good OT.

The stock V3 OT may be more to spec according to the tube data sheet for a EL84, but it's still a cheap P.O.S.

For the same cost as a decent pedal you can make your VJr sit up and bark.

[mac]

Maybe mine is sounding nice because I'm using the 220V PS input, and I swap the OT terminals, the yellow and white wires IIRC. Believe it or not that made a little difference.
Power dissipation is 12W. I heard comments that some units run at 13W or higher, so the 220R should be increased to 270R or 330R.
Not bad at all for euros 109!!!

The ref Fuzz is a great pedal, I like it more than a TS. But I'm thinking of building a fet booster with tone controls specificallly for the VJ.

m-theory, do you have the schem of your EL34 version?

mac

[m-theory]

Maybe mine is sounding nice because I'm using the 220V PS input

Could be that, or perhaps you've got a different idea of what sounds good.  Tone is, after all, very subjective.  Not sure what your actual wall voltage is, but in the states, it's usually considerably higher than the rating on most equipment.  In the case of this amp and others, that are biased quite high to begin with, this pushes tubes well beyond where they're most happy. 

But I'm thinking of building a fet booster with tone controls specificallly for the VJ.

I like FET boosters a lot. 

m-theory, do you have the schem of your EL34 version?

I don't, but I can find one, correct the values that I changed, and email it to you.  It's gonna be a few days though, because I've got rehearsals the next three evenings, and gigs Fri/Sat/Sun.  If you haven't seen anything in a week, email me to remind me, ok? 

[mac]

Could be that, or perhaps you've got a different idea of what sounds good.  Tone is, after all, very subjective.

Yes. Well, I'm 43
I like farty Fuzz Face-like tones that make my amp dancing like an unbalanced wash machine.
I like those 22uf bypassing the 1K5 resistors in the VJ, and perhaps a bigger cap at the EL84 cathode.
The Red Fuzz filters lows so it can suit the taste of younger people

mac

[CLAAS]

43?
Young Fart

[tackleberry]

I got my Vjr with the intention of modding it alot. I did some basic stuff first like a few caps, fixed the input resister situation, and added a pot so its gain and volume. I did figure out pretty fast the stock board is junk doesnt take much to screw up the aluminum traces on it. I was going to gut it and rebuild it. But figured as I was pretty much going to be building a complete amp I would just keep it this way and build another amp. So I left it with the few mods so it can be run pretty close to clean and just use pedals with it. I use a BSIAB and a DoubleD with it. Works pretty good this way with a stereo chorus sending the other signal to my other small amp I built. I can get just about any tone I need with those 2 pedals.

[mac]

I should not modify the amp. Since everything can be disconnected from the board, I'd build a new pcb with better caps, etc, trying to match the tubes holes in the chassis with the new pcb.

Some ago I opened it and experimented with it live. I put 6.8uf poly caps across the 1K5 resistors, and a good low ESR 100uf electro ¿Panasonic? bypassing the cathode resistor, and that changed the sound a lot.

mac