Monthly Archives: April 2014

1967 Baldwin Burns Jazz Bass

Due to a shortage of information on what’s become one of my favorite basses ever, I’m attempting to compile as much as I know about this instrument in a single place.
Baldwin Burns Jazz BassMine is a 1967. Burns manufactured the Jazz Bass from ’64-’65 ( Baldwin purchased the company in ’65 and the Jazz bass was continued until ’70 (


  • 22 frets
  • 30.5″ scale
  • Controls:
    • Pickup selector – 4-position rotary switch
      • Contrabass – Neck Pickup, with highs rolled off
      • Bass – Neck and Middle Pickups
      • Treble – Bridge Pickup
      • Wild Dog – Middle and Bridge PIckups with Bridge out of Phase.
        • I added the neck pickup to ‘Wild Dog’ to give it low end that was completely missing originally. The out-of-phase sound is still there, so it’s a nice contrast to the ‘Bass’ position.
    • Tone
    • Volume
  • Burns patented Gear-o-Matik® Truss Rod Gearbox mechanism in heel of neck. geared low, i.e. requires more turns than traditional direct adjust truss rods. The modern gearing is 1:18. I don’t know if the old ones are the same. It turns easily and did take full turns where I’d normally have made only partial turns.
  • Fully adjustable bridge with roller saddles on threaded shaft for side to side adjustment
  • Burns Tri-Sonic pickups, but not split-sound that are mentioned frequently which only seem to be on the guitars. They are low impedance requiring transformers.
  • Metal-button Van Ghent tuners with a streamlined cover. (

Truss rod tool and bolt head:

Burns Gear-o-Matik® Truss Rod Wrench Burns Gear-o-Matik® Truss Rod Bolt Burns Gear-o-Matik® Truss Rod Wrench in Place
About the pickups (I contacted Burns UK and got the following response):

“Regarding the pickups – the low impedence units that you have were only made for a few years and then discontinued, never to return. Although the system worked quite well, it was massively expensive to produce/manufacture and really the same sort of sounds/tone could be achieved with the standard high impedence units which were fitted to different Burns models, at a fraction of the price. If you disconnect your pickups from the transformers, they will basically become useless and un-useable. If you try to wire high impedence units through the transformers it would probably work, but the residual noise would be ridiculous and there would be almost no high end frequencies whatsoever. All the new pickups currently supplied by Burns London are the high impedance standard units.”

He also said in another exchange:

“Regarding your E-mail to Burns London about the schematics/wiring on your Baldwin bass. There is a copy of the original UK Burns schematic printed in Paul Day’s “Green Burns Book”. However, this is a copy from an original heavily used schematic – and in all honesty is barely legible – and gives little info on component values etc.. Burns instruments were also notorious for changing spec on an almost weekly basis – this was really down to the availability of various components at that time. To make matters even more complicated, when Baldwin purchased Burns – much of the actual production moved to the large EKO plant in Italy. This also caused circuits/components to change. Regarding the “wild dog” setting – many people are under the impression that this was some sort of booster or overdrive sound. In fact, it was essentially an “out of phase” setting – which basically sucked the mid frequencies out of the signal. The pickups were normally very low impedance units and the small transformers under the pickguard boosted the coils back up. This was an attempt to achieve a very “clean” un-distorted type sound.”

Baldwin Burns Jazz Bass - BodyBaldwin Burns Jazz Bass - Controls

Other feature of note – the awesome scroll headstock.

Baldwin Burns Jazz Bass - Head

I use Thomastik-Infeld flatwound Jazz Bass strings – JF324 – they’ve gotten expensive, but they really make the bass speak well. It’s amazingly consistent all over the neck with a nice fat sound around and above the 12th fret. It came with unidentified roundwound strings that were unremarkable.

I have a ’75 Gibson EB-3 that I also love, but it’s hard to play live because its sound is inconsistent on the lower frets, ranging from really dead to super boomy. I’ve had good luck recording it, but I don’t play it any more, though, because I moved the now 10-year old Thomastik strings to the Baldwin bass.
'75 Gibson EB-3

I would like to draw up a schematic with as much info as I can determine. The transformers are only labeled 3206 and 3136, which I’ve found is consistent with other Baldwin/Burns instruments, but I doubt I’ll ever figure out any more than that.

Sound Clips:

George Urgo Blues Band from our last summer in Philadelphia. I recorded this live at a Sunday brunch at Juniper Commons, April 2015.

Guitar, Vocals – George Urgo
Drums – Ben Diamond

Bass – Andrew Nelson

Other links:

Recovering Data From a Broken USB Flash Drive

Last year I was able to extract all the data from a friend’s 16GB USB flash drive that was broken in half when the laptop it was still plugged into was put in a knapsack. It was broken almost cleanly through, so I broke it all the way to expose the guts, cut open a USB cable and soldered wires to the power connector PC board traces. The exposed parts of the traces for the data connectors, however, were torn off and what remained was too small to solder to. So I stuck two sewing pins through a piece of 1/4″ lauan, lined up the pins with the data traces, wiggled them through the insulating coating and after a few tries had a slow but steady transfer of the nearly 16GB of critical, non-backed up data. On my first try, I was holding the board and the pins (needed enough weight to make contact), but my hand cramped up before it could finish. After that, I steadied the board with two finishing nails and weighted it down. All I had to do then was tip toe and keep the cats away from it. Kinda surprised it worked.

Hotwiring a USB Drive

Repaired Presonus HP4 v1 Headphone/Monitor Amp

My very useful Presonus HP4 v1 headphone amp fried last Fall. I found another on eBay for not too much, but I hung onto the old one. Turns out they’re full of this quad amp IC, MC33079P, and one on the input stage failed. The chip is obsolete, but I replaced it with an MC33079PG that seems to be the same. Or at least compatible.

The hardest part was un-soldering a 14-pin IC without destroying the PC board. I added a socket in case something else had (and would again) aggravated the chip, but after several long days’ use it seems to be doing fine.

What spurred me on to do this was that channel 1 of the replacement HP4 failed. A check with a VOM from the power pins to the signal pins shows the same lack of potential (15V DC) across one of the amp’s pins. The power supplies seem good, so I think it is the chip that’s failing, and not the power supply or a current limiting resistor.

Next project is to replace the channel 1 chip on the replacement HP4 and try to make two complete units.


Update: after receiving a question about suppliers, here’s where I found the IC and the socket (thanks, Jordan):
MC33079PG IC
14-pin Socket

Update II:
– Apparently these amps are version 1 which use a 16V AC power supply. The latest ones seem to use a 12V DC power supply. I’m not sure what other components have changed. Since I can’t find the original ICs, it’s a good bet, they’ve changed in the newer ones as well.
– 3 months later the repaired HP4 is working great.
– I repaired my other one with a bad channel 1 and a scratchy channel 4. Made the same IC replacement. So far, so good.