Treble/Bass Onboard Preamp?

Vincent Vespa

New member
Hey there! I was wondering if you guys might know where I can find a stacked Treble/Bass Onboard Preamp like the EMG ETC (http://emginc.com/products/index/104/146/4) but for guitar. I've been looking for one for a couple hours with no luck.

I don't suppose anyone knows if I could just wire the ETC in to my guitar and not have any problems? It's made for bass, though. :-\
 
Re: Treble/Bass Onboard Preamp?

Kind of. I'm looking for something with two independent controls in one stacked knob. I'm looking to have two preamps, one that controls treble and bass and the other one mids and gain (Spectrum-1). I'm looking to have an all around EQ using just two pot spots (leaving one for volume control). I'm not sure if a stacked Bass/Treble preamp exists, but I figured I'd ask.

Worst case scenario, I'll use the EXG (which is a bad scenario at all! :D).
 
Re: Treble/Bass Onboard Preamp?

The bass circuit would work for guitar, but not as well as it does for bass or as well as a guitar-specific unit would because those are usually tailored for bass guitar freqs. I put a Jackson active bass circuit in a guitar once years ago (20dB boost/cut) but since it was eq'd for bass and not guitar, the bass frequencies were not as drastically affected as they were on a bass guitar. The highs had a bit of a funky spank with the treble way up, but that was about it.

There was a thread here a while back by Frank or Evan asking what onboard stuff we'd like to see SD work on. Shoulda thought about that then, if it wasn't mentioned.
 
Re: Treble/Bass Onboard Preamp?

The bass circuit would work for guitar, but not as well as it does for bass or as well as a guitar-specific unit would because those are usually tailored for bass guitar freqs. I put a Jackson active bass circuit in a guitar once years ago (20dB boost/cut) but since it was eq'd for bass and not guitar, the bass frequencies were not as drastically affected as they were on a bass guitar. The highs had a bit of a funky spank with the treble way up, but that was about it.

There was a thread here a while back by Frank or Evan asking what onboard stuff we'd like to see SD work on. Shoulda thought about that then, if it wasn't mentioned.
Which one do you think would work better? The EXG or ETC?
 
Re: Treble/Bass Onboard Preamp?

Have been looking for info on the the Starr switch onboard EQ and can't find jack. any info I could get would be great, A friend of mine brought over an Ibanez MC-400 w/ the original active EQ replaced w/ a Starr switch board (as well as different P/U's, and concentric pots for the EQ) and I can't find any info so far. any help would be awesome (again)
 
Re: Treble/Bass Onboard Preamp?

If you want shelf EQs it really matters where the cutoff frequency is.
 
Re: Treble/Bass Onboard Preamp?

Its just a builtin pedal... Unless you really exoect to fiddle with knobs a lot in midsong, forego it. Theyre finicky, unnecessarily complex, and consist of $20 worth in components (controls for a 65-cent retail/15-cent wholesale opamp chip), for often $200ish, never do anything particularly amazing that other things cant, yet give you the added "confidence" of 70-200 more solder joints that can get buggered up inside your control cavity. And, with most configs, one goes out and you lose the entire signal.
 
Re: Treble/Bass Onboard Preamp?

Its just a builtin pedal... Unless you really exoect to fiddle with knobs a lot in midsong, forego it. Theyre finicky, unnecessarily complex, and consist of $20 worth in components (controls for a 65-cent retail/15-cent wholesale opamp chip), for often $200ish, never do anything particularly amazing that other things cant, yet give you the added "confidence" of 70-200 more solder joints that can get buggered up inside your control cavity. And, with most configs, one goes out and you lose the entire signal.

+1. Seems like a complicated, and unnecessary way to do things.
 
Re: Treble/Bass Onboard Preamp?

BTW, what is a good electronics forum where I can ask people to help me package up a few opamps to have a shelf EQ at cutoff frequencies I want?

And BTW, are those preamps discussed here shelf EQs?
 
Re: Treble/Bass Onboard Preamp?

I think Bartolini preamps are designed to work with passive pups as well as actives - TCT series, which can still be found.
 
Re: Treble/Bass Onboard Preamp?

These types of onboard preamps are easy to install and very stable today. Battery space and battery life is the only real consideration. I personally don't find them beneficial for my needs, but I do appreciate the functionality for some players. They are used with great success. The Starr system is an old design and I doubt it is even in production anymore.

And BTW, are those preamps discussed here shelf EQs?

Adjustable 2-band. Bass EQ (20hz here) is generally fixed shelving as you would imagine for that HZ. High-end is adjustable to 4 settings. 2 shelves fixed at different frequencies and 2 constant Qs set at different bell curves.

Cheers and respect,

RG
 
Re: Treble/Bass Onboard Preamp?

BTW, what is a good electronics forum where I can ask people to help me package up a few opamps to have a shelf EQ at cutoff frequencies I want?

And BTW, are those preamps discussed here shelf EQs?

Sabratone has some layouts for musicman guitar and bass onboard preamps (built on TI 062 chips or later direct replacement generations, the "preamp" itself costs a whopping 2x $0.22, and the rest is pots caps resistors etc to control it). You can build them into the cavity or toss em in a pedal enclosure (much like any pedal, should you really wanna, can be wired in before the jack inside an instrument). Built in, it's always at your fingertips, though things csn get fragile/cramped. But...outboard it, and you only ever need one.

Btw, almost ALL preamps for guitar/bass use the same chips (or 072s for better but less battery time), and are essentially different control schemes for the same damn thing. Recently blew one in an Ibanez SR-1015 (stupid battery box that allowed reversing by accident + no protection diode on the circuit)... tried replacing it, but maintenance on those tiny flimsy and sloppy (!!! - ibanez japan got em OEM from friggin mighty mite, of all places) was too much of a pain. and once I got that done I realized even the friggin PICKUPS shorted out, just tore everything out and got a $150 set of openbox SD Blackouts for Bass online... Bit disappointed that theyre actually WEAKER than old APB Lightnin Rods and the blackout thing is somewhat of a misnomer, but stilll sooooo much better. And no more freakin preamp pcb, who needs that junk. Just 25k pots.
 
Re: Treble/Bass Onboard Preamp?

I think Bartolini preamps are designed to work with passive pups as well as actives - TCT series, which can still be found.

ALL preamps are "for" passive pups, but generally work with actives (or ANY other signal, long as it isn't powerful enough to damage them, if badly designed, or make them compress and actually clip the signal, if well designed).... Same as with amps, lol. Onboard preamps are just a piece of an amp schematic moved over to the guitars side.

Bte, MOST "active" basses have factory passive pups, theyre just talking about active EQ.

...active pups have a preamp epoxy'd inside already, but usually without controls (exception: 80s Duncan APB/APJ pickups had minitoggles for 3 band boosts). However, nothing keeps you from chaining any number of other active (+/- vs. just cut or "-" as normal potentiometers do) EQs after it (onboard, on some pedals, on some amps).

Most onboard preamps for anything are a copy of one of two ancient SS bass amps' equalization options - basic 3-4 band or "parametric" 3 band with "mid frequency" sweeper controlling which part of the mids you wish to alter.... NOTHING MORE.

Easier to buy a graphic EQ pedal with a gazillion bands. Can do way more complex shapes too....AND CHEAPER!!!!
 
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Re: Treble/Bass Onboard Preamp?

Sabratone has some layouts for musicman guitar and bass onboard preamps (built on TI 062 chips or later direct replacement generations, the "preamp" itself costs a whopping 2x $0.22, and the rest is pots caps resistors etc to control it). You can build them into the cavity or toss em in a pedal enclosure (much like any pedal, should you really wanna, can be wired in before the jack inside an instrument). Built in, it's always at your fingertips, though things csn get fragile/cramped. But...outboard it, and you only ever need one.

Btw, almost ALL preamps for guitar/bass use the same chips (or 072s for better but less battery time), and are essentially different control schemes for the same damn thing. Recently blew one in an Ibanez SR-1015 (stupid battery box that allowed reversing by accident + no protection diode on the circuit)... tried replacing it, but maintenance on those tiny flimsy and sloppy (!!! - ibanez japan got em OEM from friggin mighty mite, of all places) was too much of a pain. and once I got that done I realized even the friggin PICKUPS shorted out, just tore everything out and got a $150 set of openbox SD Blackouts for Bass online... Bit disappointed that theyre actually WEAKER than old APB Lightnin Rods and the blackout thing is somewhat of a misnomer, but stilll sooooo much better. And no more freakin preamp pcb, who needs that junk. Just 25k pots.

Yeah, I already have all the parts here and schematics for various configurations.

But I need some form of forum where I can ask people how to compute the capacitors and resistors around the opamp so that I can place the shelf EQ where I want. I already went through the trouble of finding out where I want them with a mastering software.
 
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