spi
Well-known member
Here's a double build report to wrap up 2022.
Up first is the GuitarPCB "Black Dog", which is their adaptation of the RAH. This is marketed as a "Jimmy Page in a Box" pedal, mimicking his Hiwatt sound from 1970 recordings. I was interested for several reasons: First, as a lifelong fan of Led Zeppelin it just sounds cool. Second, I always wanted to try one of the Howard designs from Catalinbread. Lastly, the circuit is a variation on the Box of Rock. I have the Van Pelt, which is also a BoR variant (using 3 cascading mosfet boosts for gain). The Van Pelt grew on me over time, and has become one of my favorites. The RAH is similar but adds a feedback loop, and I was curious what it would do to the sound. A blowout price when BarryGPCB cleared out old revisions of this board ended up the deciding factor.
This one sounds pretty good to my ears. It has that stacked-mosfet gain sound I've come to know from the Van Pelt, but a bit more touch sensitivity. It's not a high-gainer, which is to be expected from an amp of that era, but has the gain for LZ type tones.
Second up is the Dark Esbat. I wasn't sure what to expect from this. It's not really a "Tony Iommi in Box", as it's not trying to replicate his amp or sound, rather it's marketed as a boost endorsed (and presumably used) by Tony. It's supposed to capture his Rangemaster tone--but with three op-amps it's definitely not a Rangemaster (It calls for MC33178s, and a common sub is TL072, but I used 4580Ds). And with bass and treble controls, and mid-range switch, it's way more versatile than a treble booster. After getting it boxed up last night, I got on this forum and found this fresh post by @MattG: Ember Boost and Dark Esbat: same circuit. He recognized that this is really a Spark Boost in disguise.
Last night while playing around I found it's very effective as a tweak-able boost, but it also does a great job of fattening Strat single coils when at unity volume. There's lots of settings to explore and I only got the tip. The odd thing is the output and gain knobs--both seem to impact the volume level, but there isn't really a lot of overdrive gain--bumping up the gain only adds volume, and sometimes a mild amount of grit, but other times not really noticeable. I don't think it's an issue with my build because I see some other build reports confirm the same.
Both these use waterslide decals (LZ and BS themed, my favorite part was finding matching fonts, which are obscured by the knobs in my pictures), with a top coat of Envirotex. This was my second attempt to use Envirotex and while I learned a bit the first time, I realized I'm still on the upward learning curve with this coating. The coating could be better, but the imperfections don't bother me.
The knobs on the Dark Esbat are temporary. The knobs I ordered were too large and hung over the side... I had to borrow ones planned for a different build in the meantime, until I can order replacements. Embarrassingly, there's a burnt capacitor box in there too .
I should also mention these two sounded great together, stacking the boost into the OD.
Up first is the GuitarPCB "Black Dog", which is their adaptation of the RAH. This is marketed as a "Jimmy Page in a Box" pedal, mimicking his Hiwatt sound from 1970 recordings. I was interested for several reasons: First, as a lifelong fan of Led Zeppelin it just sounds cool. Second, I always wanted to try one of the Howard designs from Catalinbread. Lastly, the circuit is a variation on the Box of Rock. I have the Van Pelt, which is also a BoR variant (using 3 cascading mosfet boosts for gain). The Van Pelt grew on me over time, and has become one of my favorites. The RAH is similar but adds a feedback loop, and I was curious what it would do to the sound. A blowout price when BarryGPCB cleared out old revisions of this board ended up the deciding factor.
This one sounds pretty good to my ears. It has that stacked-mosfet gain sound I've come to know from the Van Pelt, but a bit more touch sensitivity. It's not a high-gainer, which is to be expected from an amp of that era, but has the gain for LZ type tones.
Second up is the Dark Esbat. I wasn't sure what to expect from this. It's not really a "Tony Iommi in Box", as it's not trying to replicate his amp or sound, rather it's marketed as a boost endorsed (and presumably used) by Tony. It's supposed to capture his Rangemaster tone--but with three op-amps it's definitely not a Rangemaster (It calls for MC33178s, and a common sub is TL072, but I used 4580Ds). And with bass and treble controls, and mid-range switch, it's way more versatile than a treble booster. After getting it boxed up last night, I got on this forum and found this fresh post by @MattG: Ember Boost and Dark Esbat: same circuit. He recognized that this is really a Spark Boost in disguise.
Last night while playing around I found it's very effective as a tweak-able boost, but it also does a great job of fattening Strat single coils when at unity volume. There's lots of settings to explore and I only got the tip. The odd thing is the output and gain knobs--both seem to impact the volume level, but there isn't really a lot of overdrive gain--bumping up the gain only adds volume, and sometimes a mild amount of grit, but other times not really noticeable. I don't think it's an issue with my build because I see some other build reports confirm the same.
Both these use waterslide decals (LZ and BS themed, my favorite part was finding matching fonts, which are obscured by the knobs in my pictures), with a top coat of Envirotex. This was my second attempt to use Envirotex and while I learned a bit the first time, I realized I'm still on the upward learning curve with this coating. The coating could be better, but the imperfections don't bother me.
The knobs on the Dark Esbat are temporary. The knobs I ordered were too large and hung over the side... I had to borrow ones planned for a different build in the meantime, until I can order replacements. Embarrassingly, there's a burnt capacitor box in there too .
I should also mention these two sounded great together, stacking the boost into the OD.
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