BOSS pedal trimpot compendium
- Pepe
- Posts: 1685
- Joined: Thu Aug 16, 2018 2:19 pm
- Location: Germany
- SBZ: Multi Platinum
- Bossarea: Double Platinum
- Contact:
BOSS pedal trimpot compendium
█ → you can tweak these trimpots by ear to adjust the pedal's performance to your taste
█ → don't think about touching these without technical skills and/or an oscilloscope
AW-2 Auto Wah
- RT-1 (LED brightness of optocoupler? I read that somewhere ...)
BF-1 Flanger
- VR-1 clock frequency
- VR-2 bias
- VR-3 mixing balance
- VR-4 resonance
BF-2 Flanger
- VR-5 resonance
- VR-6 bias
- VR-7 clock frequency
→ calibration process explained by cctsim (screenshot from the first BossArea Forum)
CE-2 Chorus
- VR-3 bias
CE-2B Bass Chorus
- VR-3 bias
CE-3 Chorus
- VR-3 bias
CEB-3 Bass Chorus (analog version)
- RT-1 bias
DC-2 Dimension C
- RT-1 bias B
- RT-2 bias A
DD-2/3 Digital Delay and DSD-2/3 Digital Sampler/Delay
- RT-1 (main board) clock "high end"
- RT-2 (volume board) clock "low end"
DD-3 Digital Delay (modern)
- RT1 clock adjustment
- RT2 clock adjustment
DM-2 Delay
- VR-1 set-point (minimising distortion)
- VR-2 clock leakage
- VR-3 delay time set-point
DM-2W Delay
- VR-13 max. delay time
DM-3 Delay
- RT-1 BBD bias
- RT-2 leakage
- RT-3 clock frequency (delay time set-point)
HF-2 Hi Band Flanger
- VR-5 resonance
- VR-6 BBD bias
- VR-7 clock set-point
LM-2 Limiter
- VR-5 (?)
- VR-6 (?)
MZ-2 Digital Metalizer
- RT-1 clock frequency
NF-1 Noise Gate
- VR-3 sustain level
- VR-4 decay time
OC-3 Super Octave
- L2 sealed trimpot
- L3 sealed trimpot
OD-2 Turbo OverDrive
- RT-1 (master level?)
PH-1R Phaser
- VR-1 bias
PS-2 Digital Pitch Shifter/Delay
- VR-5 clock frequency
PS-3 Digital Pitch Shifter/Delay
- RT-1 bias
RV-3 Digital Reverb/Delay
- RT-1 bias
SG-1 Slow Gear
- VR-3 bias
SP-1 Spectrum
- VR-3 gain adjustment
TW-1 T Wah
- VR-3 frequency adjustment
VB-2 Vibrato
- VR-4 BBD clock set-point
- VR-5 BBD bias
█ → don't think about touching these without technical skills and/or an oscilloscope
AW-2 Auto Wah
- RT-1 (LED brightness of optocoupler? I read that somewhere ...)
BF-1 Flanger
- VR-1 clock frequency
- VR-2 bias
- VR-3 mixing balance
- VR-4 resonance
BF-2 Flanger
- VR-5 resonance
- VR-6 bias
- VR-7 clock frequency
→ calibration process explained by cctsim (screenshot from the first BossArea Forum)
CE-2 Chorus
- VR-3 bias
CE-2B Bass Chorus
- VR-3 bias
CE-3 Chorus
- VR-3 bias
CEB-3 Bass Chorus (analog version)
- RT-1 bias
DC-2 Dimension C
- RT-1 bias B
- RT-2 bias A
DD-2/3 Digital Delay and DSD-2/3 Digital Sampler/Delay
- RT-1 (main board) clock "high end"
- RT-2 (volume board) clock "low end"
DD-3 Digital Delay (modern)
- RT1 clock adjustment
- RT2 clock adjustment
DM-2 Delay
- VR-1 set-point (minimising distortion)
- VR-2 clock leakage
- VR-3 delay time set-point
DM-2W Delay
- VR-13 max. delay time
DM-3 Delay
- RT-1 BBD bias
- RT-2 leakage
- RT-3 clock frequency (delay time set-point)
HF-2 Hi Band Flanger
- VR-5 resonance
- VR-6 BBD bias
- VR-7 clock set-point
LM-2 Limiter
- VR-5 (?)
- VR-6 (?)
MZ-2 Digital Metalizer
- RT-1 clock frequency
NF-1 Noise Gate
- VR-3 sustain level
- VR-4 decay time
OC-3 Super Octave
- L2 sealed trimpot
- L3 sealed trimpot
OD-2 Turbo OverDrive
- RT-1 (master level?)
PH-1R Phaser
- VR-1 bias
PS-2 Digital Pitch Shifter/Delay
- VR-5 clock frequency
PS-3 Digital Pitch Shifter/Delay
- RT-1 bias
RV-3 Digital Reverb/Delay
- RT-1 bias
SG-1 Slow Gear
- VR-3 bias
SP-1 Spectrum
- VR-3 gain adjustment
TW-1 T Wah
- VR-3 frequency adjustment
VB-2 Vibrato
- VR-4 BBD clock set-point
- VR-5 BBD bias
- Pepe
- Posts: 1685
- Joined: Thu Aug 16, 2018 2:19 pm
- Location: Germany
- SBZ: Multi Platinum
- Bossarea: Double Platinum
- Contact:
Re: BOSS pedal trimpot compendium
I received a TW-1 this week and when I opened it to clean it I saw that it has a trimpot like so many other BOSS pedals. I thought that we could list all the BOSS pedals with internal trimpots and sum up what they affect. And we can highlight those that can be tweaked by any user (like the BF-2's feedback trimpot to make the flanger self-oscillate) and also those that require higher technical skills and/or an oscilloscope, etc.
I will put all the information in the first posting. Thanks in advance for all your help!
I will put all the information in the first posting. Thanks in advance for all your help!
- laurie
- Posts: 1649
- Joined: Fri Aug 17, 2018 2:07 am
- Location: Canada
- SBZ: Multi Platinum
- Bossarea: Multi Platinum
Re: BOSS pedal trimpot compendium
Deleted - full list below.
Last edited by laurie on Fri Jun 12, 2020 11:32 pm, edited 1 time in total.
- Pepe
- Posts: 1685
- Joined: Thu Aug 16, 2018 2:19 pm
- Location: Germany
- SBZ: Multi Platinum
- Bossarea: Double Platinum
- Contact:
Re: BOSS pedal trimpot compendium
Thanks a lot, laurie!
Can you check your info about the PS-2 again? And is my information about the trimpots of the analog chorus pedals correct (bias)?
Which ones are those in your opinion that can be tweaked if the average player is not fully satisfied with the pedal's performance? I'd recommend the resonance trimpots of the BF-2 and HF-2. What about the trimpots of the AW-2 and TW-1? I have another envelope filter by KORG and adjusting the trimpots had a huge impact on the performance (in the positive way).
Can you check your info about the PS-2 again? And is my information about the trimpots of the analog chorus pedals correct (bias)?
Which ones are those in your opinion that can be tweaked if the average player is not fully satisfied with the pedal's performance? I'd recommend the resonance trimpots of the BF-2 and HF-2. What about the trimpots of the AW-2 and TW-1? I have another envelope filter by KORG and adjusting the trimpots had a huge impact on the performance (in the positive way).
- laurie
- Posts: 1649
- Joined: Fri Aug 17, 2018 2:07 am
- Location: Canada
- SBZ: Multi Platinum
- Bossarea: Multi Platinum
Re: BOSS pedal trimpot compendium
PS-2 typo... VR4 and VR5
More to follow
More to follow
- chromandre
- Posts: 215
- Joined: Sat Aug 25, 2018 3:15 am
Re: BOSS pedal trimpot compendium
I'm going to guess there is no reason to adjust these right?
....fwiw, I was actually able to do the PH-1R by ear. I had one in for repair and likely because someone moved the trim pot. there is an extremely small range of pleasing results sitting on split hairs of adjustment. Basically if your PH-1R sounds correct at max depth and slowest rate, don't touch the trim pot!
-
- Posts: 273
- Joined: Sat Aug 18, 2018 2:11 am
- SBZ: Platinum
Re: BOSS pedal trimpot compendium
I have a complete screen capture of that post:
https://1drv.ms/u/s!At7zhavfCGMhu5Vkqq6 ... A?e=At5jpZ
I'll leave that link active indefinitely in case anyone needs it.
-Scott
- Pepe
- Posts: 1685
- Joined: Thu Aug 16, 2018 2:19 pm
- Location: Germany
- SBZ: Multi Platinum
- Bossarea: Double Platinum
- Contact:
Re: BOSS pedal trimpot compendium
Wow! A screenshot from the original BossArea Forum. That brings back some memories.
Thanks a lot for the link, sclitheroe! I included it in the first posting.
Thanks a lot for the link, sclitheroe! I included it in the first posting.
- Pepe
- Posts: 1685
- Joined: Thu Aug 16, 2018 2:19 pm
- Location: Germany
- SBZ: Multi Platinum
- Bossarea: Double Platinum
- Contact:
Re: BOSS pedal trimpot compendium
You are absolutely right. I did that as well with my PH-1R after replacing the electrolytic capacitors. The sweet spot is clearly noticeable. I used a synthesizer for the process. I played a chord in hold mode so I had the chance to fiddle around with the trimpot until I was satisfied with the result.chromandre wrote: ↑Sat May 30, 2020 11:16 pm....fwiw, I was actually able to do the PH-1R by ear. I had one in for repair and likely because someone moved the trim pot. there is an extremely small range of pleasing results sitting on split hairs of adjustment. Basically if your PH-1R sounds correct at max depth and slowest rate, don't touch the trim pot!
- laurie
- Posts: 1649
- Joined: Fri Aug 17, 2018 2:07 am
- Location: Canada
- SBZ: Multi Platinum
- Bossarea: Multi Platinum
Re: BOSS pedal trimpot compendium
These notes are OPINIONS. Use your judgement before attempting any adjustments.
Everywhere that says "should be OK to be adjusted by ear"... you will likely need a scope to get it back to factory setting. So please be sure this is really what you want to do.
Take care messing with vintage pedals. Incorrect settings can affect the resale value of the pedal.
“Scope” means something like a Tektronix 1002B (this is the one I use).
===========
AW-2 Auto Wah
- RT-1 LED brightness of optocoupler. Do not adjust without a scope.
BF-1 Flanger – unable to verify, no schematic available.
- VR-1 clock frequency. If clock frequency should be OK to be adjusted by ear.
- VR-2 bias. If BBD bias, do not adjust without a scope.
- VR-3 mixing balance. If BBD balance, do not adjust without a scope.
- VR-4 resonance. If resonance, should be OK to be adjusted by ear.
BF-2 Flanger
- VR-5 resonance. Set by ear is OK.
- VR-6 bias. Do not adjust without a scope.
- VR-7 clock frequency. Do not adjust without a scope.
CE-2 Chorus
- VR-3 BBD bias. Do not adjust without a scope.
CE-2B Bass Chorus
- VR-3 BBD bias. Do not adjust without a scope.
CE-3 Chorus
- VR-3 BBD bias. Do not adjust without a scope.
CEB-3 Bass Chorus (analog version) – unable to verify, no schematic available.
- RT-1 bias. If actually bias, do not adjust without a scope.
DC-2 Dimension C
- RT-1 BBD bias B. Do not adjust without a scope.
- RT-2 BBD bias A. Do not adjust without a scope.
DD-2/3 Digital Delay (all versions of DD-3) and DSD-2/3 Digital Sampler/Delay
- RT-1 (main board) clock "high end". Can be adjusted by ear. Better with a scope.
- RT-2 (volume board) clock "low end". Can be adjusted by ear. Better with a scope.
DM-2 Delay
- VR-1 BBD bias. Do not adjust without a scope.
- VR-2 clock leakage. Do not adjust without a scope.
- VR-3 delay time set-point. Can be adjusted by ear.
DM-3 Delay
- RT-1 BBD bias. Do not adjust without a scope.
- RT-2 clock leakage. Do not adjust without a scope.
- RT-3 clock frequency (delay time set-point). Can be adjusted by ear.
HF-2 Hi Band Flanger
- VR-5 resonance. Can be adjusted by ear.
- VR-6 BBD bias. Do not adjust without a scope.
- VR-7 clock set-point. Can be adjusted by ear. Better with a scope.
LM-2 Limiter
- VR-5 Feedback. Might be OK to adjust without a scope. No service notes available, so set-point and effect of adjusting unknown.
- VR-6 Threshold trim. Should be OK to adjust without a scope.
MZ-2 Digital Metalizer
- RT-1 clock frequency. Should be OK to be adjusted by ear. Better with a scope.
NF-1 Noise Gate
- VR-3 sustain level. OK to be adjusted by ear. Better with a scope.
- VR-4 decay time. OK to be adjusted by ear. Better with a scope.
OC-3 Super Octave – unable to verify, no schematic available.
- sealed trimpots
OD-2 Turbo OverDrive
- RT-1 2.5V rail set. Do not adjust without a volt-meter.
PH-1 Phaser
- VR-1 FET bias. Do not adjust without a scope.
PH-1R Phaser
- VR-4 FET bias. Do not adjust without a scope.
PS-2 Digital Pitch Shifter/Delay
- VR-4 clock bias. Do not adjust.
- VR-5 clock frequency. No set-point information available. Do not adjust.
PS-3 Digital Pitch Shifter/Delay
- RT-1 bias. Do not adjust without a scope.
RV-3 Digital Reverb/Delay
- RT-1 bias. Do not adjust without a scope.
SG-1 Slow Gear
- VR-3 bias. Can be adjusted by ear… but should use a volt-meter.
SP-1 Spectrum
- VR-3 gain adjustment. Can be adjusted by ear… but should use a scope.
TW-1 T Wah
- VR-3 frequency adjustment. Do not adjust without a scope.
VB-2 Vibrato
- VR-4 BBD clock set-point. Can be adjusted by ear… but should use a scope.
- VR-5 BBD bias. Do not adjust without a scope.
Everywhere that says "should be OK to be adjusted by ear"... you will likely need a scope to get it back to factory setting. So please be sure this is really what you want to do.
Take care messing with vintage pedals. Incorrect settings can affect the resale value of the pedal.
“Scope” means something like a Tektronix 1002B (this is the one I use).
===========
AW-2 Auto Wah
- RT-1 LED brightness of optocoupler. Do not adjust without a scope.
BF-1 Flanger – unable to verify, no schematic available.
- VR-1 clock frequency. If clock frequency should be OK to be adjusted by ear.
- VR-2 bias. If BBD bias, do not adjust without a scope.
- VR-3 mixing balance. If BBD balance, do not adjust without a scope.
- VR-4 resonance. If resonance, should be OK to be adjusted by ear.
BF-2 Flanger
- VR-5 resonance. Set by ear is OK.
- VR-6 bias. Do not adjust without a scope.
- VR-7 clock frequency. Do not adjust without a scope.
CE-2 Chorus
- VR-3 BBD bias. Do not adjust without a scope.
CE-2B Bass Chorus
- VR-3 BBD bias. Do not adjust without a scope.
CE-3 Chorus
- VR-3 BBD bias. Do not adjust without a scope.
CEB-3 Bass Chorus (analog version) – unable to verify, no schematic available.
- RT-1 bias. If actually bias, do not adjust without a scope.
DC-2 Dimension C
- RT-1 BBD bias B. Do not adjust without a scope.
- RT-2 BBD bias A. Do not adjust without a scope.
DD-2/3 Digital Delay (all versions of DD-3) and DSD-2/3 Digital Sampler/Delay
- RT-1 (main board) clock "high end". Can be adjusted by ear. Better with a scope.
- RT-2 (volume board) clock "low end". Can be adjusted by ear. Better with a scope.
DM-2 Delay
- VR-1 BBD bias. Do not adjust without a scope.
- VR-2 clock leakage. Do not adjust without a scope.
- VR-3 delay time set-point. Can be adjusted by ear.
DM-3 Delay
- RT-1 BBD bias. Do not adjust without a scope.
- RT-2 clock leakage. Do not adjust without a scope.
- RT-3 clock frequency (delay time set-point). Can be adjusted by ear.
HF-2 Hi Band Flanger
- VR-5 resonance. Can be adjusted by ear.
- VR-6 BBD bias. Do not adjust without a scope.
- VR-7 clock set-point. Can be adjusted by ear. Better with a scope.
LM-2 Limiter
- VR-5 Feedback. Might be OK to adjust without a scope. No service notes available, so set-point and effect of adjusting unknown.
- VR-6 Threshold trim. Should be OK to adjust without a scope.
MZ-2 Digital Metalizer
- RT-1 clock frequency. Should be OK to be adjusted by ear. Better with a scope.
NF-1 Noise Gate
- VR-3 sustain level. OK to be adjusted by ear. Better with a scope.
- VR-4 decay time. OK to be adjusted by ear. Better with a scope.
OC-3 Super Octave – unable to verify, no schematic available.
- sealed trimpots
OD-2 Turbo OverDrive
- RT-1 2.5V rail set. Do not adjust without a volt-meter.
PH-1 Phaser
- VR-1 FET bias. Do not adjust without a scope.
PH-1R Phaser
- VR-4 FET bias. Do not adjust without a scope.
PS-2 Digital Pitch Shifter/Delay
- VR-4 clock bias. Do not adjust.
- VR-5 clock frequency. No set-point information available. Do not adjust.
PS-3 Digital Pitch Shifter/Delay
- RT-1 bias. Do not adjust without a scope.
RV-3 Digital Reverb/Delay
- RT-1 bias. Do not adjust without a scope.
SG-1 Slow Gear
- VR-3 bias. Can be adjusted by ear… but should use a volt-meter.
SP-1 Spectrum
- VR-3 gain adjustment. Can be adjusted by ear… but should use a scope.
TW-1 T Wah
- VR-3 frequency adjustment. Do not adjust without a scope.
VB-2 Vibrato
- VR-4 BBD clock set-point. Can be adjusted by ear… but should use a scope.
- VR-5 BBD bias. Do not adjust without a scope.