A few years ago, I build the PedalPCB Ember Boost, which is based on the TC Electronic Spark Booster. This is marketed as boost, which it certainly is, but the "fat" and "mid" modes also make it useful as a light overdrive; the Baxandall tone stack gives it a fairly flexible EQ. The core topology is similar to a Bluesbreaker-style pedal.
I really liked the Ember/Spark Boost in "mid" mode, but personally didn't find too much use for the "fat" or "clean" modes. I had actually started some napkin sketches of how I could mod the mode switch to be more in line with how I wanted to use the pedal.
Before I got too far with those plans, @Chuck D. Bones managed to read my mind and work his magic on the Dark Esbat. The PedalPCB Dark Esbat is based on the Black Country Customs TI-Boost ("TI" for its endorser, Tony Iommi). The Ember/Spark Boost and Dark Esbat/TI-Boost are the same circuit, with only a couple minor component value changes.
Not only did Chuck rework the mode switch, but he took it a step further than I could have, and simplified the circuit. The original circuit had some fluff; in the end, the modded version omits a whole opamp, plus a number of resistors and capacitors.
I'd been meaning to whip up a PCB of Chuck's modded Dark Esbat/Ember Boost for a while, and finally got around to it a few weeks ago. The PCBs arrived last week, and I had some time to assemble the pedal this weekend. I paired it with my pre-made buffered electrical bypass module. The enclosure is the December 2024 Limited Run from Love My Switches. The clipping arrangement is two pairs of three series diodes. For each triplet, I used two BA282 and a 1N4001.
It worked on first power up, no drama! I just sold my Ember Boost, so couldn't make a direct comparison. The role I intend for this pedal is for a touch-sensitive dirty boost/edge-of-breakup pedal with a flexible EQ, to work both as a very light drive and/or to push a medium gain drive (such as the Hard Rock Pinnacle). The nearest "competitor", and the pedal to which I was directly comparing, is the Cast Iron (Lollar Overdrive). I was able to quickly dial the modded Dark Esbat in where I wanted it. It's too early to say which I prefer, as I need more time with it to get a better sense of the "feel". But straight away, I can tell it absolutely meets my expectations.
The mids switch is really well tuned: almost too well-tuned, as I couldn't figure out which setting I like the best! In theory, I like the idea of the flexibility of an actual pot for mids (or any EQ, really); but in practice, I like the simplicity of a well-tuned switch. I think this is one area where Barber pedals have really nailed the "user interface" for pedals, particularly for gigging. Pedals like the Gain Changer or Direct Drive have (at least to my ears) a really great core sound, almost perfect with all knobs at the noon position. The knobs are more for fine-tuning, rather than forcing a square peg into a round hole. And the versatility (or "changing the shape of the peg") comes from the switches, rather than having to re-tune all the pots when you want a different sound. So this pedal I feel is a nod in that direction, which I appreciate: spare me the self-induced neurosis of trying to perfectly dial in my mids, just give me a switch with a few good settings! Chuck D Bones: "hold my beer".
Any way, I'm super-happy with this build. Eagle-eyed readers will note the PCB revision is v1.1. I drew up v1.0, wasn't happy with the layout, and completely re-did it. I still didn't think it was a great layout. So I never fabbed v1.0, and instead drew up v1.1. I shamelessly stole the top-of-board shape from the Dark Esbat. After more hours than I care to admit, I ended up with what I think is a decent layout. I was able to route almost all of the traces on the front side of the board; the back is satisfyingly tidy.
I have a few extra boards that I'm happy to send out to anyone who asks, just PM me. I'm also happy to post the Gerbers if there's any interest.
I really liked the Ember/Spark Boost in "mid" mode, but personally didn't find too much use for the "fat" or "clean" modes. I had actually started some napkin sketches of how I could mod the mode switch to be more in line with how I wanted to use the pedal.
Before I got too far with those plans, @Chuck D. Bones managed to read my mind and work his magic on the Dark Esbat. The PedalPCB Dark Esbat is based on the Black Country Customs TI-Boost ("TI" for its endorser, Tony Iommi). The Ember/Spark Boost and Dark Esbat/TI-Boost are the same circuit, with only a couple minor component value changes.
Not only did Chuck rework the mode switch, but he took it a step further than I could have, and simplified the circuit. The original circuit had some fluff; in the end, the modded version omits a whole opamp, plus a number of resistors and capacitors.
I'd been meaning to whip up a PCB of Chuck's modded Dark Esbat/Ember Boost for a while, and finally got around to it a few weeks ago. The PCBs arrived last week, and I had some time to assemble the pedal this weekend. I paired it with my pre-made buffered electrical bypass module. The enclosure is the December 2024 Limited Run from Love My Switches. The clipping arrangement is two pairs of three series diodes. For each triplet, I used two BA282 and a 1N4001.
It worked on first power up, no drama! I just sold my Ember Boost, so couldn't make a direct comparison. The role I intend for this pedal is for a touch-sensitive dirty boost/edge-of-breakup pedal with a flexible EQ, to work both as a very light drive and/or to push a medium gain drive (such as the Hard Rock Pinnacle). The nearest "competitor", and the pedal to which I was directly comparing, is the Cast Iron (Lollar Overdrive). I was able to quickly dial the modded Dark Esbat in where I wanted it. It's too early to say which I prefer, as I need more time with it to get a better sense of the "feel". But straight away, I can tell it absolutely meets my expectations.
The mids switch is really well tuned: almost too well-tuned, as I couldn't figure out which setting I like the best! In theory, I like the idea of the flexibility of an actual pot for mids (or any EQ, really); but in practice, I like the simplicity of a well-tuned switch. I think this is one area where Barber pedals have really nailed the "user interface" for pedals, particularly for gigging. Pedals like the Gain Changer or Direct Drive have (at least to my ears) a really great core sound, almost perfect with all knobs at the noon position. The knobs are more for fine-tuning, rather than forcing a square peg into a round hole. And the versatility (or "changing the shape of the peg") comes from the switches, rather than having to re-tune all the pots when you want a different sound. So this pedal I feel is a nod in that direction, which I appreciate: spare me the self-induced neurosis of trying to perfectly dial in my mids, just give me a switch with a few good settings! Chuck D Bones: "hold my beer".
Any way, I'm super-happy with this build. Eagle-eyed readers will note the PCB revision is v1.1. I drew up v1.0, wasn't happy with the layout, and completely re-did it. I still didn't think it was a great layout. So I never fabbed v1.0, and instead drew up v1.1. I shamelessly stole the top-of-board shape from the Dark Esbat. After more hours than I care to admit, I ended up with what I think is a decent layout. I was able to route almost all of the traces on the front side of the board; the back is satisfyingly tidy.
I have a few extra boards that I'm happy to send out to anyone who asks, just PM me. I'm also happy to post the Gerbers if there's any interest.
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