Jump to content

Using preamps in guitars


Mr_Buttman

Recommended Posts

Hi guys.

As many of you already seen i've recently finished my bass build and what interesting about it is that i used the onboard preamp in guitar/bass for the first time.

Before this build i never understood why are so many knobs in most of good basses and why bass players need them and guitar players does not.

So when choosing electronics for Rhino bass i was looking for best pickups (so i choodes Nordstrand DC). Then i explored several forums and found that these pickups combination with Aguilar OBP is the best. It have 3-band equalizer, 400/800 Hz mid frequency swithc, active/passive switch, volume and blend controls.

What can i say? I now fully understand why so many high class basses (like Alembic) have so much controls. The sound changes drastically when you use EQ, you can make almost any sound you want from bass - it can be warm, sharp, round, bright. There is no noise. After active mode the passive one looks poor. Of course i understand that you can use passive bass and external preamps with equalizers but this is another story.

So what's the question? If the bass preamps work so well and used in so many high-class products why can't we see anything like this in guitars?

Do any of you have experince of using built in preamps with EQ in guitars?

Link to comment
Share on other sites

In my opinion, those preamps can alter the tone to the point where you lose the bass' character. Of course, not all preamps are created the same but when you take great care and attention in building an instrument, you want its character to come through the speakers.

To me, its like using EMG actives in an electric guitar. It doesn't matter what the guitar is made of when you use EMGs because they completely mask the guitar's character.

Link to comment
Share on other sites

Since you mentioned Alembic:

They built, through their connection to the Grateful Dead, one of the first recognized and used pre-amps in a guitar. The Strat-O-Blaster. It is simply a unity gain buffer. It can be used as a booster although it tends to change the tone dramatically as the gain increases.

When I built my first guitar, I built a multiple gain staged onboard pre-amp. single/bucker/bucker with on/off swtiching and coil taps on the buckers. there is an onboard stereo effects loop with its own volume control, two tone controls (treble and bass) and a straight guitar volume. taking the fx loop out of the equation, you can have the sound of a lot of different guitars. Then blend in the color you want.

The pre is touch sensitive more akin to an acoustic than an electric - the sound doesn't change, it just gets louder.

Does it work? yes. Is it complete overkill? yes.

Link to comment
Share on other sites

i have a specific booster for then duncan jazz neck pickup on my bez. it is only kicked in on the neck position only to help bring a little more slam to the amplifier with the same sound as the jazz.

Link to comment
Share on other sites

A lot of people bitch about pre-amps making an instrument sound sterile or whatever. The fact of the matter is, they lower the output impedance of the instrument which significantly reduces to completely eliminates cable losses. I'm quite the advocate of my differential pre-amps purely for this purpose and I intend on installing one in my 1951-5 bass project. Less for the noise reduction (which it will do anyway) but more for the ability to oomph a signal to drive a cable. Not entirely unlike those Neovin pre-amps you posted about, Tim37.

Link to comment
Share on other sites

It isn't really do to with impedance of the input for whatever the guitar is plugged into. The issue I am referring to as a "pro" for pre-amps is the cable run's capacitance combined with passive output impedance levels forms a basic low-pass RC filter. Dropping the output impedance by buffering the output prior to the cable shifts the cutoff point out of the audible range. You're still right that loading a pickup can be desirable in some instances.

Tim37 nailed it, mentioning that guitarists are finicky and prefer a bigger palette than bassists. Hell, last time I was in a band I had one tone that nailed it all. No problems. Locked in with the drummer, job done. Bassists seem to have a more KISS approach (no Gene Simmons pun or whatever intended) whereas guitarists want a tutu, deep-sea diving helmet, clown shoes, lipstick, deely-boppers, Vulcan ears, false teeth, fake plastic boobs, cardigan, shaved legs kind of setup. Then add more on top of that. Guitarists like dancing about in pedal minefields like a Morris dancer on crack.

I think the most mileage a guitarist gets out of controls onboard are more in the field of switching options than equalising or bringing outboard "onboard".

Apologies in advance to any guitarists out there....but you know that this is true....

Link to comment
Share on other sites

...whereas guitarists want a tutu, deep-sea diving helmet, clown shoes, lipstick, deely-boppers, Vulcan ears, false teeth, fake plastic boobs, cardigan, shaved legs kind of setup. Then add more on top of that. Guitarists like dancing about in pedal minefields like a Morris dancer on crack.

I'm not sure what you're trying to say here. Some guitarists are ridiculous with effects but some are not. Regardless, this has nothing to do with the original topic, does it... or am I missing your point?

Would I add a preamp to my guitars? Maybe.... it depends... With a preamp usually comes more gain, which drastically changes the sound and dynamics. If all you're interested in is a buffer, you can achieve that with a pedal pretty easily.

With Bass, we're taking about a different application and different amplification, effects, speakers etc..

Link to comment
Share on other sites

Having a buffer as outboard sort of defeats the point unless it is meant to drive a much longer cable run. An onboard buffer eliminates high end cable loss. Gain is not always a product of buffering, for example the ones I use are specifically unity gain.

You're the one that brought up the buffering, not me... and I never said that gain is a product of buffering so I don't understand why you bring that up.

Link to comment
Share on other sites

We're tripping up over each other somewhat. I muddied the waters by bringing up buffers, or "pre-amps without EQs" as a response to yours about EMGs. The EMG pre-amps (at least, the "original" ones) and pickup designs were not without its flaws, however it is not fair to damn all pre-amps/buffers in the same sense. This is patently not true. Mr Buttman specifically referred to pre-amps *with* EQs so perhaps we need to get away from buffers/pre-amps without EQs.

As mentioned, Aguilar OBPs are a safe bet for most basses. Well-designed pre-amps/EQs flatter certain known aspects of an instrument's tone. Guitars are perhaps less easy to pin down although some benefit from a simpler, less all-affecting EQ like a treble boost or whatever.

Link to comment
Share on other sites

Also worth noting is that an active EMG pickup itself has an onboard preamp and buffer encased inside the pickup - anyone using EMGs is already experiencing what it's like to use a guitar with a preamp.

In my experience most guitarists like their guitar controls simple and prefer processing to happen further downstream, whereas bassists are more open to the idea of onboard multiband EQs and preamps.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...