mybud
Well-known member
So, I've been venturing into the arcane territory of BBD chip circuits of late. First, GPCB's Mini-Me, a surprisingly rich-sounding chorus given it only has rate and depth controls. Then, PPCB's Caesar for which board and parts I waited a fair length of time (delays this side, not from the suppliers).
I obtained the clock and BBD chips from eBay and couldn't wait to build it. Took my time, checked and double-checked component values and soldering integrity: no joy. To be more precise, it was clearly amplifying the signal as expected but not doing the chorus thing.
Someone helpfully posted working voltages and when comparing these to mine, I observed that fiddling with the trimmer got my values into the ballpark. Lo and behold, the pedal formerly known as Julia spoke volumes of rich and occasionally quite wacky chorus/vibrato. Just what I was looking for, given Walrus Audio's demos of said pedal.
While I understand the Julia-Caesar connection in naming the pedal, I thought that I should not go in the Roman direction (Morituri te salutant struck me as too violent and gladiatorial, Dear Henry (as in Kaiser) too obscure even for my taste), and so on. I thought the Chinese Empress Wu 624-705 (https://en.wikipedia.org/wiki/Wu_Zetian) might fit the bill, since 'She was the only legitimate female sovereign in the history of China. Under her 40-year reign, China grew larger, corruption in the court was reduced, its culture and economy were revitalized, and it was recognized as one of the great powers of the world.'
I want to thank the OP of the working voltages (alas, I can't recall exactly who did this), @jeffwhitfield for helping double-check and verify the original order from eBay and general encouragement and @MichaelW for posting a successful build report.
FWIW, I subbed a TL062 for the unobtanium 022 (eventually settling on an LM358P for the LFO section), a known functioning BL3207 from Banzai and left the MN3102 in place (since I have no subs therefor), and finally swapped out the 4558 for another variant of the same chip. None of this might have made any difference were it not for the OP's original working voltages.
So, I'm very glad that I have a working Caesar which sound fab to my ears and does a nice range of chorus/vib effects somewhat akin to PPCB's Abyss but subtly different.
Thanks for reading. That's all, folks!
I obtained the clock and BBD chips from eBay and couldn't wait to build it. Took my time, checked and double-checked component values and soldering integrity: no joy. To be more precise, it was clearly amplifying the signal as expected but not doing the chorus thing.
Someone helpfully posted working voltages and when comparing these to mine, I observed that fiddling with the trimmer got my values into the ballpark. Lo and behold, the pedal formerly known as Julia spoke volumes of rich and occasionally quite wacky chorus/vibrato. Just what I was looking for, given Walrus Audio's demos of said pedal.
While I understand the Julia-Caesar connection in naming the pedal, I thought that I should not go in the Roman direction (Morituri te salutant struck me as too violent and gladiatorial, Dear Henry (as in Kaiser) too obscure even for my taste), and so on. I thought the Chinese Empress Wu 624-705 (https://en.wikipedia.org/wiki/Wu_Zetian) might fit the bill, since 'She was the only legitimate female sovereign in the history of China. Under her 40-year reign, China grew larger, corruption in the court was reduced, its culture and economy were revitalized, and it was recognized as one of the great powers of the world.'
I want to thank the OP of the working voltages (alas, I can't recall exactly who did this), @jeffwhitfield for helping double-check and verify the original order from eBay and general encouragement and @MichaelW for posting a successful build report.
FWIW, I subbed a TL062 for the unobtanium 022 (eventually settling on an LM358P for the LFO section), a known functioning BL3207 from Banzai and left the MN3102 in place (since I have no subs therefor), and finally swapped out the 4558 for another variant of the same chip. None of this might have made any difference were it not for the OP's original working voltages.
So, I'm very glad that I have a working Caesar which sound fab to my ears and does a nice range of chorus/vib effects somewhat akin to PPCB's Abyss but subtly different.
Thanks for reading. That's all, folks!
