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#1
I plan on modding a epiphone valve junior, i already have the parts for the brightness switch and the r1 and r2 resistors. i plan on adding a capacitor parrellel to c6, online they say that you need about 100uf and 450v, i dont want to order the parts online but i m able to get ahold of a 100uf 370v, will i be able to add this to the c6 slot and stil lhave it reduce the 60khz and 120 khz hum.
-caleb
#2
If it says 450v, it means that anything less is likely to blow. You need 450V.
Quote by corduroyEW
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#3
Quote by tubab0y
If it says 450v, it means that anything less is likely to blow. You need 450V.

well i tihnk that the ones that come stock are a lot less than 450 seeing as they re prettty whimpy capacitors
#4
It should say on the stock ones what they are.
Quote by corduroyEW
Cheap amps are "that bad". They suck up your tone like cocaine at Kate Moss' party.


I am Michael!
#5
metal film caps have pretty good voltage. electrolytic caps are the ones with low voltage.
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#6
I would think that 370v capacitors should be able to handle a VJ. I know the ax84 p1 uses a 350v capacitor in the power stages but if you can you really should try to get 450v capacitors just in case i am wrong.
#7
well this is a large filtering capactior that im adding to the high voltage side, will it still filter if its a metal film or electrolytic
#8
You should be safe with 370V, although I would recommend 450 just for the breathing room. I replace C6 in mine with a 100uf/385V cap and I've had no problems. If I measured the voltage correctly in mine, I got 348V running across C6. Of course that's in my amp, measure yours just to be safe.
#9
Quote by Whole Lotta Led
You should be safe with 370V, although I would recommend 450 just for the breathing room. I replace C6 in mine with a 100uf/385V cap and I've had no problems. If I measured the voltage correctly in mine, I got 348V running across C6. Of course that's in my amp, measure yours just to be safe.


I'd go with a higher rated cap, just to be safe. I've had smaller electrolytics explode and do quite a bit of damage (cracking a plastic enclosure), so I wouldn't want to be anywhere near a larger one if it went off.
"Everybody, one day will die and be forgotten. Act and behave in a way that will make life interesting and fun. Find a passion, form relationships, don't be afraid to get out there and fuck what everyone else thinks."
#10
I sure hope mine doesn't explode

I haven't had any problems though, I probably will swap it on down the road just for the piece of mind.
#11
Are you modding the new or old version VJ? Most of the modsites are for the old version with the stripe in the middle of the faceplate. The new one has improved filtering, too much filtering can make an amp sound dead.
The Laney Thread are big and clever. No exceptions.
#12
I just did these two mods yesterday actually. Why not just buy the darn capacitor online? I think it was like $1.50 for two of them. By the way these are glorious mods, the sound quality improved greatly, there's a fair bit more preamp gain and so it gets a little crunchier without getting messy, and the whole tone is more articulate and less dark. I never thought that putting $.87 worth of parts in my epi would practically double its sound quality. I added extra filtering to the new version too, (it has two more of the same size caps I believe- 5 insted of 3) and I don't think it has made the amp sound dead at all, you can definately get away with the 450V cap icap in the new version.

edit: I wish people would start posting some mods for the new versions, especially the head.
Last edited by dullsilver_mike at Sep 28, 2007,
#13
yah i already have the capacitor for te brightness thats the one thats like 150 for two but a large capacitor like the 100uf/450v those are like 10 bucks not 150. i also have the two resitors for r1 and r2 or something like that
#14
ok, I found them, I bought mine at electonic goldmine, just google it. They cost $2.50 each, I was mistaken, but that's still well worth it I'd say. I've ordered from there several times, it's worth it if you happen to be buying some other stuff to double up on shipping, but I understand not wanting to blow $5 after the part and shipping on one cap and then having to wait 4 days to get it.
#15
Quote by dullsilver_mike
I just did these two mods yesterday actually. Why not just buy the darn capacitor online? I think it was like $1.50 for two of them. By the way these are glorious mods, the sound quality improved greatly, there's a fair bit more preamp gain and so it gets a little crunchier without getting messy, and the whole tone is more articulate and less dark. I never thought that putting $.87 worth of parts in my epi would practically double its sound quality. I added extra filtering to the new version too, (it has two more of the same size caps I believe- 5 insted of 3) and I don't think it has made the amp sound dead at all, you can definately get away with the 450V cap icap in the new version.

edit: I wish people would start posting some mods for the new versions, especially the head.

The new version is the same as the old version, just with some better power supply filtering and some grounding issues corrected. The tone is the same, the signal path is the same, all component values in the signal path are the same, only it's a bit harder to get the board out. The head is the exact same thing as the new combo.
#16
I'm looking at a picture of DVM's Valve Junior Mod Page right now and it does'nt have as many stock caps as my epi head did yesterday when I opened it up and installed the 450v Cap (DVM's has three in line-, mine had four in line and one out of the line-though I don't know if it was something else or just wired in parallel but placed differently), maybe they didn't change the schematic documentation to match, I haven't looked, but I know what I saw with my own eyes and the number of stock caps is definately different.

That said, you're right about it being pretty much the same. Even though the board is shaped a bit differently and is more difficult to access, the R1 R2 mod worked great for me, I didn't see an open C3 slot on the board anywhere though so I didn't do the bright switch. Did I just not look carefully or has this been ommitted from the new board? Anyone know?
#17
Yeah, the new board is missing the C3 slot. And the new one has better filtering, too.

EDIT: While we're on the subject of VJs, how do you get the board out without stripping the screws? Mine is way too tight to get out.
#21
i just changed the resistors and it sounds great(by great i mean amazing, big difference), im not going to add the other capictor cuz im happy with how it is now, im kinda mad about not being able to do brighness (due to mine being a v2) i didnt realize that only v1's had a c6 slot, is there still a way to add the brightness switch
#23
no just as simple, i did the whole thing, including getting out the head and such in about 15 minutes ( i plugged in the iron went to work and it was all hot by the time i got to it )
#24
Quote by mercinariesgtr
i just changed the resistors and it sounds great(by great i mean amazing, big difference), im not going to add the other capictor cuz im happy with how it is now, im kinda mad about not being able to do brighness (due to mine being a v2) i didnt realize that only v1's had a c6 slot, is there still a way to add the brightness switch

Yeah, you can just solder the capacitor over R6. There's enough wire poking over the board to make the connection, and it should hold pretty well.
Quote by Whole Lotta Led
^What mods have you done so far? Not much else I can do to mine, besides nfb and a new ot.

I've done a bright cap, input impedances, and within the next few days I'm going to lower C1 to .0068. I might also try some other mods that I've thought up, but I don't have the right values for that yet. I'll let you know if I do them.
Last edited by cokeisbetter at Sep 28, 2007,
#25
Quote by cokeisbetter
Yeah, you can just solder the capacitor over R6. There's enough wire poking over the board to make the connection, and it should hold pretty well.

I've done a bright cap, input impedances, and within the next few days I'm going to lower C1 to .0068. I might also try some other mods that I've thought up, but I don't have the right values for that yet. I'll let you know if I do them.

do you have a v2
#27
^probably only when u work around big capacitors... and if u remember to unplug it and stuff i think u'd be fine...
Call me "Shot".

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Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


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#28
^With the combo you'll need to drain the filter caps unless they changed that in the newer models. The head has bleeder resistors so you should be fine.
#30
^if u can mod a VJ it would be such a monster tho...
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


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#31
I wouldn't mind getting another one to mess around with. So far I've done, master volume, tone control, gain switch, pentode/triode mode, raised the input impedance, and new tone caps, and swapping C6 if you want to call that a mod. About the only thing I'll trade for it now is a Plexi or a Bluesbreaker
#32
Quote by Whole Lotta Led
I wouldn't mind getting another one to mess around with. So far I've done, master volume, tone control, gain switch, pentode/triode mode, raised the input impedance, and new tone caps, and swapping C6 if you want to call that a mod. About the only thing I'll trade for it now is a Plexi or a Bluesbreaker

is urs v1 or v2
#35


Just solder one end of the cap to the switch and the other end to a lead on R6 (doesn't matter which end).
#36
Quote by mercinariesgtr
do you have a v2

Yes.
Quote by kurtlives91
Do you have to take any safety precautions when modding a VJ?

It's got the bleeder resistors... I hope.
#39
i used 1/2 watts , i just did the brightswtich mod and it sounds great, so far i h ave swapped the r1 and r2 and done the brightswitch, its a completely different amp now, im thinking of adding the 8ohm jack too that seems simple, just split the brown ( common) and then wire the other side to an output jack
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