andrewsrea
Member
- Build Rating
I have to admit I bought this PCB as a challenge, as I could never bond with a Tube Driver (neither Chandler, nor the BK Butler). I found them to be like a cross between a Big Muff (furry big sound that has limited use in music without getting lost in a mix) and a Fuzz Face (unlike a Muff, it cleans up and thins out when you turn the guitar volume down). Also, the EQs are quickly over-bearing. My 'challenge,' was to get it a little more mid-range friendly and to sit in a mix better, while retaining some Tweed amp characteristics.
I first built it stock and within 5 minutes of playing, I burnt my ears out there was so much treble and as 'scooped' in the midrange as scooped gets.
Accordingly, my first move was replacing the C6 hi-pass cap (470pF allowing too much highs and not enough mids to pass) with a 180K resistor in series with a 1nF cap, which created a high pass beginning at 884Hz. Note that I tried more aggressive Cap + resistor combos at 884Hz (18K+ 10nF, for example), which made the mids too pronounced and caused a weird phase shift as I played.
Then I connected a 10nF cap at the juncture of R8 & R10 and the other end to ground, to bleed even more treble and self-noise.
QUICK EDIT: I auditioned A TL072, OPA2134, JRC4556. JRC4560, MC1458 and a LM833. OPA2134 won the spot! The MC1458 was noisey and undefined and the tone got better as I used the faster dual op amps. The OPA2134 was close to the TL072, with drastically less noise, was a hair crisper and a little more headroom.
With the internal MOSFET trims a little above 'off,' the gain and level at 2 o'clock, the Low just a little above 'off' and the Hi off - it sounds pretty much on target. It still has mucho high end but works both in a 1964 BF Twin Reverb and a Marshall JCM800 100w (less pedal gain and more level). Overall, more gain range that is amp-like distortion., yet you can get it to do the Big Muff thing with some tweaking. To me, it was in that 80w Hi-power Tweed Twin with 2 Alnico magnet Celestion Creme speakers sound.
I used my AMI Special, which is set up to sound like a Stat, Tele, P-90 or Les Paul, very quickly. The pedal responded best to single coils but did justice to the humbuckers.
I think I am going to replace the low and hi pots with audio taper next, as the linear taper feel like all or nothing. I anticipate the audio taper will make those controls more usable.
IMHO this also needs an inverting buffer at the end before the volume, as the circuit is inverting (sound coming out is 180 degrees out of phase with the signal) and I always feel inverting designs fight my playing. However, I currently am not motivated to mod this board to that extent.
I'd be interested in hearing how others who built this PCB, did with their builds.
I first built it stock and within 5 minutes of playing, I burnt my ears out there was so much treble and as 'scooped' in the midrange as scooped gets.
Accordingly, my first move was replacing the C6 hi-pass cap (470pF allowing too much highs and not enough mids to pass) with a 180K resistor in series with a 1nF cap, which created a high pass beginning at 884Hz. Note that I tried more aggressive Cap + resistor combos at 884Hz (18K+ 10nF, for example), which made the mids too pronounced and caused a weird phase shift as I played.
Then I connected a 10nF cap at the juncture of R8 & R10 and the other end to ground, to bleed even more treble and self-noise.
QUICK EDIT: I auditioned A TL072, OPA2134, JRC4556. JRC4560, MC1458 and a LM833. OPA2134 won the spot! The MC1458 was noisey and undefined and the tone got better as I used the faster dual op amps. The OPA2134 was close to the TL072, with drastically less noise, was a hair crisper and a little more headroom.
With the internal MOSFET trims a little above 'off,' the gain and level at 2 o'clock, the Low just a little above 'off' and the Hi off - it sounds pretty much on target. It still has mucho high end but works both in a 1964 BF Twin Reverb and a Marshall JCM800 100w (less pedal gain and more level). Overall, more gain range that is amp-like distortion., yet you can get it to do the Big Muff thing with some tweaking. To me, it was in that 80w Hi-power Tweed Twin with 2 Alnico magnet Celestion Creme speakers sound.
I used my AMI Special, which is set up to sound like a Stat, Tele, P-90 or Les Paul, very quickly. The pedal responded best to single coils but did justice to the humbuckers.
I think I am going to replace the low and hi pots with audio taper next, as the linear taper feel like all or nothing. I anticipate the audio taper will make those controls more usable.
IMHO this also needs an inverting buffer at the end before the volume, as the circuit is inverting (sound coming out is 180 degrees out of phase with the signal) and I always feel inverting designs fight my playing. However, I currently am not motivated to mod this board to that extent.
I'd be interested in hearing how others who built this PCB, did with their builds.
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