Andy Summers Preamp PCB

[mrmorrison]

I'm building an Andy Summers Telecaster copy, since they're all sold out and they were $15k. I have sourced pretty much everything, the last piece that remains is the preamp which is a modified Eric Clapton mid-boost PCB. Does anyone have Andy Summers guitar or have access to a schematic for the modified PCB? Any help would be greatly appreciated!

[mrmorrison]

I'm building an Andy Summers Telecaster copy, since they're all sold out and they were $15k. I have sourced pretty much everything, the last piece that remains is the preamp which is a modified Eric Clapton mid-boost PCB. Does anyone have Andy Summers guitar or have access to a schematic for the modified PCB? Any help would be greatly appreciated!

Anything?

[David Schwab]

Andy's real preamp was nothing like that Fender preamp.... just a simple transistor booster.

You can find a lot of booster schematics on the internet. He said it gave him a little bass boost, so probably a non JFET booster would work well. A JFET booster usually brightens up the tone as well.

Forget that hacked together Fender crap... just make your own booster.

[Mark Hammer]

Be careful what you wish for. I've had assorted on-board preamps for 30 years, and, unless well planned out, I caution against them for a few reasons.

First, you have to change the batteries, and that can result in eventual thread stripping on the guitar, so be careful.

Second, they need to be WELL secured. Loose wiring and a booster simply makes for louder noise.

Third, too much boost at the guitar can be fun if the guitar always goes straight into an amp, but can wreak havoc with pedals between guitar and amp that are designed around an assumed signal level. To whit, I had made myself a TS-808 spec'd Tube Screamer, and used it with a preamp-equipped guitar. Hated it, hated it, hated it. Couldn't begin to imagine why others liked it. Then I bought myself another guitar and left the preamp off. Plugged into the TS and fell in love. The TS wants a weaker signal to do what it does. Similarly, things like compressors, noise gates, phasers, and some BBD-based pedals, want a signal that is not too hot.

My advice is to not let the gain exceed 3-4. That will provide some oomph if you need it, but not push pedals so hard that you can't compensate easily with the guitar volume pot. Remember that if you turn down an uncompensated volume pot you'll lose highs through loading, and if you turn down a bypass-cap compensated volume pot and follow it with a treble-preserving preamp, you can find yourself with too tinny a tone for your liking.

[David Schwab]

Mark, I agree here. I have preamps or buffers in most of my basses, but none of my guitars, except for my FirstAct GuargeMaster, which has a factory installed preamp. I did have a JFET buffer/booster in my Tele, but it was too bright with it.

From what I've heard about Summer's real preamp, it sounds like something similar to the old BC Rich preamp. That didn't make it brighter, and actually boosted the lows somewhat for a thicker tone.

So I agree that the correct sounding preamp is important, and not to use too much gain.

[alierrett]

Have you had any luck finding out about this preamp yet? I'm in the same place as you. Know the specs of the rest of the guitar but just want to know what preamp he uses. Its definitely a modified clapton boost

[David Schwab]

Have you had any luck finding out about this preamp yet? I'm in the same place as you. Know the specs of the rest of the guitar but just want to know what preamp he uses. Its definitely a modified clapton boost

The real preamp was a home made job that was in the guitar when he bought it from one of his guitar students.

[Mike Sulzer]

Third, too much boost at the guitar can be fun if the guitar always goes straight into an amp, but can wreak havoc with pedals between guitar and amp that are designed around an assumed signal level.

It could be more than just the signal level, which you could take car of by turning down the volume on the guitar down. The pedal input might rely on loading the guitar signal down to reduce the high frequencies. You cannot do this if you have a preamp.

[David Schwab]

It could be more than just the signal level, which you could take car of by turning down the volume on the guitar down. The pedal input might rely on loading the guitar signal down to reduce the high frequencies. You cannot do this if you have a preamp.

I think it's safe to assume all pedals these days have high impedance inputs. I can't think of a single pedal designed to load the pickups, and that wouldn't work with active pickups like EMGs, or if the pedal is was after another pedal.

Also turning down the volume on a passive guitar will roll off high end.

In an old interview in Guitar Player Magazine, Summers said the preamp made the sound a bit thicker, and a bit louder, probably like the preamps in the original BC Rich guitars. It certainly didn't remove high end, since his guitar tone on the Police records is quite bright and chimey.

[Mike Sulzer]

I think it's safe to assume all pedals these days have high impedance inputs. I can't think of a single pedal designed to load the pickups, and that wouldn't work with active pickups like EMGs, or if the pedal is was after another pedal.

Also turning down the volume on a passive guitar will roll off high end.

In an old interview in Guitar Player Magazine, Summers said the preamp made the sound a bit thicker, and a bit louder, probably like the preamps in the original BC Rich guitars. It certainly didn't remove high end, since his guitar tone on the Police records is quite bright and chimey.

The germanium transistor fuzzface still has a following. Some even hunt down old stockpiles of germanium transistors and select ones with the right beta.

Loading the pickup is something to consider if you are making an active guitar. It is the simplest way to get rid of the resonant peak, giving a bland response that is most flexible if you want to make active tone controls (especially ones that include a tunable peak).

[David Schwab]

The germanium transistor fuzzface still has a following. Some even hunt down old stockpiles of germanium transistors and select ones with the right beta.

Yeah, but if you look into it you will see they are also often modified to operate better. Same thing with the old wah pedals. It's common to add buffers to the input.

Not the same thing as the preamp in question though.

Loading the pickup is something to consider if you are making an active guitar. It is the simplest way to get rid of the resonant peak, giving a bland response that is most flexible if you want to make active tone controls (especially ones that include a tunable peak).

Yeah, like this:

Audere Audio Bass Guitar Preamp with Z-Node Switch

But getting back to the original question... Summer's preamp is just a bipolar transistor booster, such as the one in the original BC Rich guitars, or the Bartolini TC1.

It doesn't have any EQ built in, but was just a byproduct of the circuit, unlike the Fender version. If you ever played an old BC Rich, the booster also adds a bit of a low end boost, but it's rather subtle. The high end is not attenuated, however, as it would be if the input was loading the pickups. The gain is just weighted more towards the low end.

There are loads of bipolar booster circuits on the 'net that would work better in this application than trying to find the Fender circuit, and be more authentic as well.