Onboard Guitar Preamp/Boost

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rstites

rstites

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Anyone around here use an onboard preamp and/or boost on their guitar? For that matter, does anyone know of someone who sells pcb's to build your own?

I have a couple of old guitars with switches mounted on them that have long been disconnected. I thought it'd be worth a try to see if I can get something to work for nice clean boost on the guitar with those for the fun of it. I could perf-board up a simple JFET or Op Amp boost easily enough but figured I'd see what other have tried first.

Note: this will be going into a hot amp, so I really want something that serves the purpose of an OD pedal for boosting, rather than needing volume boost as that's not going to happen!
 
Well, other than the usual suspects, EMG and Neal Moser (BC Rich), I've only seen a few that attempted to do this. I've never seen a DIY. Seems like it'd be a pretty easy thing to do, though. Wouldn't think the board itself would be too big, and with a battery, would probably fit in most guitars. You could even add some miniature pots on the board (set & forget tone, drive, boost, etc.). Starting to sound like it might be a fun project... I'd love to see what you come up with!
 
Also the Music Man JP models, Luke 3, and the Valentine have one onboard
 
Yeah, I can board something up and give it a whirl. Getting 20 dB clean boost from a single transistor really isn't that difficult. I'd probably used a FET to keep current consumption down, and I like JFET's for this, but a MOSFET has a nice high input impedance so as not to load the pickups at all. Even if I didn't know how to design amplifier stages already, several of the DIY web pages have well designed versions of that.

For some reason though, I swear I saw someone with little PCB's for sell for this purpose several years ago and now I don't see them around. Yes, a little perf board or vero strip deal would do just fine.

Assuming the schematic I found is correct, it looks like the EMG boost is just a couple of op amps - one as a clean gain stage and the other as a driver (unity gain) stage. It's pretty simple too.
 
There's a company called Artec that builds onboard boosts, clean preamps, and similar for guitars. The prices are right at ~$20!

However, sorting schematics, it looks like I could build a ZVEX SHO on a little perfboard and put it in there. I've never played one, thought I wish I would have realized years ago that I could stuff a single transistor boost into a bare metal enclosure, have a kindergartner paint it, and sell it for a couple of hundred bucks. I never thought there was much money in the boutique pedal world, but maybe there was! :)
 
I have one on my Custom Shop Ironbird. It’s awesome.
 
i use SPC with SA single coils, works perfect, i like it better than a TS or boost pedal
 
I've seen in a book a guy took apart an MXR Microamp pedal and put it in his guitar, battery life is 1500 hours.

The Guitar Handbook has a circuit built on perfboard that uses one opamp.
 
Btw, I found that General Guitar Gadgets carries some small boards that work for this, including the Micro amp one mentioned above, and a general purpose boost board to build a variety of FET-based boosts on.

I'll probably explore that way, but have to finish building my digital delay first......too many projects! :)
 
Uli Roth does this with his sky guitar. There's a clip about it on youtube.
 
I use to have an afterburner in my Jackson but I ended up ripping it out, I swear it just added mud to how it sounded.
 
Yeah, any particular boost can definitely become a mud-machine. This really becomes a problem with a true clean boost. Generally, you want to roll the bass off a bit to prevent mud, even though you may not want it to be apparent that you're rolling it off. It's a fine line.

I like the old SD-1 in front of my amps. I do have a couple of pedal-based FET boosts I've built that are pretty good. I'll most likely just adapt one of those and try it out.

The real problem here is that it's my two old Charvels with the small electronics cavity, so there isn't much extra room in there. However, at one time both had EMG's in them with a switch. I just figure I might as well try something with those switches. Otherwise, they just set there filling the old holes!

If I like it enough, I'll retrofit it to some other guitars. If not, I'll try something else.
 
I have one on a Valentine. It gets really shrill if you don't compensate. Nice to have on here and there, but overall, I rarely use it.
 
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