Im having problems after completing the wiring for the boost. my volume pot is really sensitive and with my amp volume barely on (< 9:00) and my guitar volume on 10 it is mildly overdriving the amp. my amp is a epi Vjr. this is with no boost on. i have it wired the same way that it shows on the diagram except i had to move the TBX to the back pot and the boost in the middle. my pickups are Lace Hot Golds. anybody who has installed this kit i would appreciate your help. was it like this for you??? could i have put the 250k pot in the volume and the 50k for the boost pot??? or should i put a 250k pot instead of the 50k pot for the volume?? it just seems really loud as compared to before and the pickups are around the same output.i know the boost is always on but it is not always adding drive. i have listened to every demo available and i never get their clean tone and there drive just sounds creamy and mine sounds harsh. could it be my amp is too small (Epi valve jr 5 watt combo). thanks for your help.
Last edited by Blackie08 at Feb 7, 2009,
Check my post here:


FYI, it isn't your amp...this guitar setup loves tube amps, even 5w ones.

I've never used the Epi Valve Jr, but if you can, try pushing those tubes as much as you can (create a really gritty sound), and then turn the bottom pot up slowly. When using clean settings, back off on the boost, or it will sound very harsh.
the vj overdrives at low volume. it is the amp. EL84 tubes tend to drive at lower volumes than other amps, and the vj is el84 driven. mine starts to break up at about 9:00.

thats not to say the vj isnt a good amp. it is a great amp. it just has low headroom.
Gibson SG Faded
Epi VJ Stack

Quote by Øttər
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But it really shouldn't be the problem of "harsh sound". I've plugged my strat with the tbx kit into some really cheap solid state amps, and it works fine...with his 5w tube amp, it really should do great. My midboost sounds best when I have the Fender BJ at Volume = 10+, Master = usually 2.5 (any more is way too loud for a small room setting).
but thats 15w, with 2 el84, and a tonestack.

the vj is 5w, 1 el84, no tonestack. very, very low headroom.

however, the harsh sound thing, i will admit, is wierd. i have spiked the mids on my distortion at low gain and it sounds pretty good, so idk. maybe use the old trick of backing off on the guitar's volume a little instead of the amp's.
Gibson SG Faded
Epi VJ Stack

Quote by Øttər
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thanks for the help guys. i played my strat through my OD pedal (SD twin tube classic) and the problem goes away completely. no funky volume stuff or anything.. the boost works great as does the tbx. i am beginning to think that it is in fact my amp. any other suggestions guys???
Yup...Angus seems to be right, it probably is your amp.

Just remember, the boost is made to boost a really gritty/dirty signal. Boosting a clean signal (even through high quality amps) does really weird things...the kind of things that will make dogs howl.

If you have a budget for an amp, check out the Fender Blues Junior:




Those three all have different speakers and colors. The speaker type will be beneficial, depending on what type of music you play.

I have the NOS, which has a Jensen speaker...the Hot Rod has a Celestion Vintage speaker...I couldn't say which is better for what kind of music, but they are both $575.

The Original BJ has a Mexican Fender speaker, and is ~$100 less than the other two models.

If your not a fan of Fender amps, you could go with the Vox AC15:


In short, your mid boost kit needs a nice tube amp that it can push its signal through. The kit was designed for Clapton's guitars, which retailed for $1300-$2500 (depending on the model). I guess fender was figuring that if you could afford the guitar, you probably have a nice tube amp...but one shouldn't assume

Also, you might find it beneficial to take your guitar to a local guitar retail shop and try some amps out.
Last edited by Bravo86 at Feb 9, 2009,
thanks for your help guys.. i was thinking of a Blues Jr, Epi Valve Senior (if they ever get released!!) or a Peavey Delta Blues 115. i play EC and SRV all of the time and if i need more OD or distortion i already have a great pedal, do ya think those r good choices??? im leaning towards the Epi cuz it has 2 6V6gt's for powertubes and i prefer the sound of 6V6's to el84's
Well...if you want to get a good EC or SRV sound, you really can't do better than the Blues Junior (especially for the money).

Clapton tones are very easy to get out of the BJ, and as for SRV tones...well...look here:


This guy loves SRV's style, and emulates his tone perfectly with his Mexican Strat and Fender BJ. Here is his YouTube page:


Nearly all of his videos are done with the Fender Blues Junior NOS.

I don't know much about the Peavy Delta Blues or any Epiphone amps, but if you go to a shop that carries the BJ, I would definitely try it out.
Last edited by Bravo86 at Feb 9, 2009,
i found the problem... the circuit board and some of its components was touching the cavity wall and effectively grounding itself and dumping the load onto the volume pot, causing a volume increase because of the increased load
Glad you fixed the problem. I'd still buy a Fender Blues Junior though
^dude...if my setup had both the VJ and the blues junior in it...holy crap...
low power, class a tube amps ftmfw!!!!
Gibson SG Faded
Epi VJ Stack

Quote by Øttər
Whenever I clean my guitars, my family wonders why it smells so good; I say that I exude a fresh citrus scent from hidden orifices.
They stopped asking