Any Interest in Fully Modded Valve Junior Combo?

[duhvoodooman***]

No, not my personal one! But I have a line on a used VJr combo for sale locally at a good price. From the photo I've seen, it looks to be in excellent condition, and it appears to be a version 2, so it wouldn't need as much upgrading as the version 1 that I own. I will inspect it carefully before purchasing, in any case.

If you've read postings here in the Mods forum by Tunghaichuan, myself and a few others, you will know that with some carefully chosen modifications, this very respectable sounding 5W Class A single-ended amp can be turned into a truly GREAT sounding amp, amazingly powerful for its size, with excellent punch & clarity.

Looking at the cost of the used amp (assuming it's a v.2), the modification parts, and the time involved to do the work, I can offer the fully modded amp for $225 with the stock speaker or $260 with an upgraded Jensen C8R. In that case, you'd get the original speaker, too. I can install pretty much any other 8" speaker of your choice, with the price adjusted according to it's cost + shipping. Shipment of the amp to you will be an additional cost, of course.

If you're interested, PM me. I can provide a full list of all the mods that will be done, upon request. If you've been reading about the Valve Jr mods and drooling over one of these little tone monsters, but aren't willing or able to undertake the mod work yourself, here's your chance to snag one! :

[duhvoodooman***]

I went ahead and bought this second Valve Jr. Contrary to what I thought from the photo, it's a version 1 combo, just like the one I already own. I've checked my figures and what's involved in the upgrade, and decided that I can do better than the prices I originally quoted. So if any of you Fretters would be interested in a genuine DVM-modified Valve Jr. combo that will stun & amaze you with its punch, power and clarity, it can be yours for $199 plus shipping. That's with the original speaker and Sovtek tubes. Those can also be upgraded, which I would do at part cost + shipping (for example, ~$35 for a Jensen C8R speaker upgrade, or ~$25 for a new set of JJ tubes).

Obviously, everything in the amp is fully functional, or I wouldn't have purchased it in the first place. I took the chassis out to inspect the components and the PCB, and everything looks to be in excellent shape. I was pleased to see that there is very little thermal discoloration around the EL84 tube socket, unlike the original combo I purchased & modded for my own use, which was amber brown from the heat. This would indicate that the amp wasn't given a lot of hard use by its previous owner. The original Sovtek tubes look to be in good shape, too. Here are a few pics I took, since I thought I'd get a good set of before, after and "work-in-progress" pics for this amp upgrade:









PM me if interested....

[marnold***]

MAN do I wish I could jump all over this one now.

[warren0728]

MAN do I wish I could jump all over this one now.

i'm with ya.....then i could sell my unmodded one....just can't do it right now....i've got a car to buy :

ww

[Kazz]

Voodoo......I might be interested......one question...are those capacitors leaking?

[duhvoodooman***]

one question...are those capacitors leaking?

No, that's just an adhesive they put around the base of the caps at the factory. I have the same stuff on my own VJr. I can see where it might prevent some vibration on the three larger filter caps, but it seems rather silly on the little ones!

[duhvoodooman***]

Since ponying up a couple of C-notes for a reworked amp is a fairly significant cash outlay, I thought I'd list a summary of what the various mods I'll be doing will accomplish:

Reliability & Safety Mods

• Reduce voltage levels and bias of EL84 power tube (stock is w-a-a-a-y too hot)
• Upgrade multiple resistors to quieter/safer metal oxide type
• Replace dinky stock volume pot with a beefier 24mm pot
• Add "bleeder" resistor to DC power rail to drain large filter caps after power-down (shock hazard reduction)

Noise/Hum Reduction

• Convert to DC filament heating
• Add more filtering to power section
• Multiple resistor & capacitor upgrades to reduce noise

Added Features

• Tone pot, patterned on Fender's Tweed-era Princeton Reverb amp
• Standby switch
• Gain boost switch
• Brightness switch

Tone & Gain Improvements

• Upgrade stock output transformer to a Hammond 125DSE--multiple tonal benefits
• Multiple resistor and capacitor changes/upgrades to improve tone, clarity, gain and punch

So you can see that this is a very extensive overhaul of the amp!

[warren0728]

you're killing me : ....someone is going to get a really great amp! i'd be all over it if i weren't buying a car in the next month...

ww

[Robert****]

Put wheels on the amp and you have both, Warren!

[F_BSurfer]

Somebody should snag this up this is a really goooooooooood deal !!!!!!!!I have a little more than 200 invested in mine not counting my labor.

[duhvoodooman***]

4/7/08 Progress Update:

Got all the parts for the upgrading of this Valve Jr combo by late last week and tore into it over the weekend. I basically got all the PCB component work done and tested/verified. So next come the more time-consuming modifications to the chassis, including changing the output transformer, converting the filament heating to DC, installing the "Tweed" tone control, and mounting the switchable mods (brightness, gain boost and standby) and new 8 & 16ohm output jacks.

Here are a couple of pics I took. The first one shows the PCB after removing all the stock components (resistors, caps and diodes) being replaced or upgraded. As you can see, there's not much left, other than a few resistors and the three power filter caps. The second one shows the board with all the new components installed. The only position still open on the board is the one labeled C3, which is the optional brightness cap's spot. I'll run wires out from those eyelets to a silver-mica cap & SPST toggle switch on the front panel. The last photo is a comparison of the puny little stock VJr OT to the much beefier Hammond 125DSE replacement:







So when the heck are one of you astute bargain-seekers gonna BUY this puppy?? :

[marnold***]

So when the heck are one of you astute bargain-seekers gonna BUY this puppy?? :

If I had my check from the gub-mint in my grubby paws (and my wife wouldn't shoot me), I'd be all over this one.

[Tone2TheBone]

I'm running a silent guess as to which one of you guys is going to cave and get this fine specimen of a custom amp.......I'm not tellin' who though I'm thinkin' will.....

[kerc]

Clips would be cool. And useful.

[duhvoodooman***]

Finished! Well, with all the electronics, at least. I still need to do some touch-up on the cabinet, which has a couple of small dings in the tolex along one top-side edge and needs a good overall cleaning. But all the mods & new features are complete and fully functional. I haven't been able to crank it up yet, since the family was sleeping when I made the last solder joint, but it sounds just like my original Valve Jr. (i.e. very good) when played at low volume through my 1x12 cab.

I'll take some photos of the completed chassis tonight and get them posted, and will record a demo clip as soon as possible.

Now, who around here has a couple of spare Benjamins in their wallet and is looking for a great deal on one hot little class A amp???

[duhvoodooman***]

Photos, as promised. A clip to follow, hopefully soon:

Underside of the chassis, showing the new Hammond 125DSE output transformer at right-rear:



Inside shot of the modded chassis, fully assembled:



Front panel, showing added feature controls. Not labeled yet, but they are (l to r) a brightness switch, insulated nylon input jack, gain boost toggle, upgraded volume pot, new "Tweed" style tone pot, standby switch, and the original power switch.



Rear panel of the chassis, showing the original 4 ohm output jack and the new 8 and 16 ohm jacks to its left. The 8 ohm jack is the former input jack that was replaced with an insulated nylon cliff jack. The 16 ohm is another cliff jack.



Inside shot of the front panel, showing the "working end" of the mods. On the right side, the new output jack is the black U-shaped plastic object between the two green toggle switch bodies. At center-top is the "Tweed" tone control assembly modeled on the classic Fender 5F2-A Princeton amp. This involves two differently rated capacitors soldered between different lugs of the volume and tone pots. Directly in front of that, with the fairly large black electrolytic capacitor mounted on it, is the bridge rectifier used to convert the tube filament heating from AC to DC, eliminating a source of 60Hz hum.



Here's a close-up of the three output jacks from the inside of the chassis. The various different impedance secondaries from the OT(green = 4 ohm, yellow = 8, white = 16) are each wired to a separate jack, and the black ground wire is daisy-chained to all three.

[ted s]

Nicely done Vood !

[warren0728]

oh man....you are killing me! :

ww

[just strum]

oh man....you are killing me! :

ww

Not only you.

Nice job DVM

I have to pass, but I wrote my guess as to who will buy it behind this line ----------