Modding Epi Valve Junior !! MORE content added!

[JE]

this is a newbie (ME) modding the valve junior. yup, my first time using a soldering iron for that matter. it gotta start somewhere right? after heavy reading over the net (www.18watt.com; i would recommand ANY person that uses tube amp to go and take a look) and getting parts from nik, here it goes:

the gut shot of the stock valve junior

stock sovtek tube (so hard to photo these glass bottles :? )

sweet little things going into the amp. start from top left, clockwise: power filter caps, mallory signal caps, carbon comp resistors and power resistors

first and foremost, the stock output transformer (OT) is really quite out of place. it's small, and it does not have the proper impedance matching the power tube. a proper OT is installed after drilling an extra mounting hole.

No prize for telling which is the stock OT.. it's just... too small

 

[JE]

modding the OT

to install the big OT, an extra hole is drilled. and voila!

the new OT installed

of cos, the OT is useless without output jack. please don't laugh.. my first 3 soldering joints :lol:

output jacks soldered

some mistakes were made when removing the PCB.. i totally destroyed two screws.. :x arghh.. gotta go and drill them off..

that's all for today. or..should i say yesterday.. haha. keep checking back yo.

 

[thor666]

Nice work. But, triple check your work, and be careful - can't stress more, after all it's 240V. Don't fire the amp up until you are so very sure.

 

[Radius_Vector]

Good job

But aspiring modders, do note that there is enough charge in a tube amp to kill, even while switched off! Im not sure about the 5W Moeity though, Just be careful guys

 

[JE]

thank you

actually the amp has near 400V voltage and yeah, the capacitor will remain charged (@400V) for sometime even after switch off. but

it's safe if you follow safty practice. not to mention it's super fun. on a side note, i always have problems unscrewing the screws in the stock stuff (pedals, amps...) anyone can give an insight why? the treads in the screws gets leveled pretty quickly. :?

 

[soundwavesmm]

Screwdrivers!

You are probably using the wrong size of screwdriver head. If it slips while turning, try a different size. You need a good set of screwdrivers with different sizes to start with.

Or maybe its just your luck that all your stuff has over tightened screws!

 

[JE]

maybe a little bit of both i think.. i managed to remove 4 out of 6..

 

[edder]

as what soundwaves says. you're probably using the wrong screwdriver size.

good luck and most importantly check the capacitors +/- direction before you take em out and put on the new ones. Fix it the other way round and you may have some nice kabooom.

 

[JE]

It's DONE!!!! :lol: :lol: :lol:

the amp just sounds amazing :lol: :lol: :lol:

i will post up more pics soon.. gotta sleep now before i think of playing it again.

 

[lifele55]

LMAO 4.23am....hahahahah

 

[suckasucks]

man i so want that amp.. just that it doenst have eq the valbee has..

 

[Reth]

Valbee...

Any mods for a valbee? Oh, JE, did you pop back the stock tubes?? or changed theh too

 

[suckasucks]

yeah any way to make the gain on the valbee more brit-voiced?

 

[Phil]

Good thread, had a good read. Very interesting, :wink:

 

[JE]

had a busy day yesterday.. now it's time for more pics :lol:

the new componets are soldered in

the trace here is cut and a resistor is placed here to prevent over-current in the tube

this is how it looks when everything is put together.

i did put back the old tubes.. want to use them as cannon fodder in case anything went wrong. they are practically indestructable :twisted:

it doenst have eq the valbee has..

true. but i think the best EQing is just change the parts in the amp. okay.. i have really limited experience in all these. but if you look at eq as signal filtering (cutting off some frequencies) it's definately going to affect the tone.

from what i read, you need a tube to power a threeband tone stack , need another one to power the effect loop, another one for tremolo, another one for reverb.. never ending .. haha.

as for valbee, maybe there are mods available gotta look around and do some reseach haha. as long as the amp is tube based, it shouldn't be too difficult to mod.. FYI component count in valve junior is less than 50. 8O

there are people who fit a KT88!!!! into a valve junior!!! 8O well..

last pic of the day: the rejects :roll:

 

[JE]

yeah any way to make the gain on the valbee more brit-voiced?

you can always pull every thing out and build a marshally amp from it 8)

nah, joking aside, you can swap out the cheapo capacitors (commonplace in low cost amps). and maybe try plugging it into a bigger cabinet first?

 

[Reth]

cool.. that sounds tough! (me no experience)

 

[imcorn]

u should consider adding a standby switch so that the tubes last longer

 

[JE]

imcorn: i did consider putting a stand-by... but

some people (.. okay.. quite a lot of them actually) warns about the misuse of the standby switch. heated tube without plate voltage applied can lead to cathod stripping (like a normal light bulb wearing out). anyway there is only 2 tiny tubes in this, and they warms up pretty fast (~30sec).

since even the les paul junior amp from Gibson (and many others) does not come with stand-by.. i decided to just cut corner a bit.. if i want to mute it, just turn down the volume

 

[JE]

NEW TUBES!!

the new tubes from ebay are IN!!!

the "glorious" boxes..

the tube itself

tried both in the amp, the tubes sound so delicious. ebay really holds good (and cheap) stuff.. one more step in to valve addiction.