Fool Audio Research Tesla Booster
I finished up another of my treble boosters today.
This is based on the old Rangemaster booster, but it's got three switchable input capacitors. The original used a 5 nF, but I always thought that was a little too thin. This one is switchable between a 10 nF, 22 nF and 47 nF.
These kinds of treble boosters were used to change the frequencies where your amp clipped back when amps like the JTM-45 and AC-30 tended to be a little flabby-sounding, due to their designs being geared around a more full-range style of reproduction. Later Vox would add, "Top Boost" and Marshall would reduce the value of their cathode bypass capacitor to shift the point where the amp clips. So these are designed for that kind of thing, just in case this is unfamiliar territory.
So the 10 nF setting (the, "toppy-est") gets you into that kind of Brian May thing to my ears. Or at least that's what I was shooting for. The 22 nF setting has a nice biting midrange thing going on. Finally, the 47 nF was my attempt at the old Tony Iommi Rangemaster sound. Not a full-range boost, but very close.
The, "Secret Sauce" here is a Tesla NPN germanium transistor. The original used PNP transistors, so it had to run on battery power only or a finicky adapter. This will run on a standard Boss adapter. There's actually no provision for battery power. These transistors break up and add some grit to the signal. Like a light overdrive. It's actually my favorite effect because it voices the guitar/amp and adds a very light and transparent overdrive at the same time.
These particular transistors are very low-noise and have an extremely pleasant tone. They aren't great at reproducing high frequencies, which probably seems a bit anti-intuitive. These transistors were made for AM radios back in the day. The problem with a lot of treble boosters is that they turn the extreme high end into kind of a harsh thing. These transistors boost the upper mids that you want (well, that I want) boosted, but then run out of steam before they get to the extreme upper range that makes your head hurt (well, makes MY head hurt, anyway). They're the perfect treble booster transistor, IMO.
Some people kick these in for a solo boost, which is a good use for 'em. Brian May used to just leave his on all the time. It was a key part of his sound. These also sound great stacked with other fuzz, overdrive and distortion effects. I think they sound amazing into a Fuzz Face, but I've also had really cool experiences using one to drive an Expandora.
There is no provision for battery power. I just want to repeat that to make sure it's clear. These are DC-only operation, but they don't need any kind of finicky power adapters like most germanium pedals. The enclosure has a durable powder coated finish. Hopefully you'll enjoy this design as much as I do.
Fool Audio Research Tesla Booster
I finished up another of my treble boosters today.
This is based on the old Rangemaster booster, but it's got three switchable input capacitors. The original used a 5 nF, but I always thought that was a little too thin. This one is switchable between a 10 nF, 22 nF and 47 nF.
These kinds of treble boosters were used to change the frequencies where your amp clipped back when amps like the JTM-45 and AC-30 tended to be a little flabby-sounding, due to their designs being geared around a more full-range style of reproduction. Later Vox would add, "Top Boost" and Marshall would reduce the value of their cathode bypass capacitor to shift the point where the amp clips. So these are designed for that kind of thing, just in case this is unfamiliar territory.
So the 10 nF setting (the, "toppy-est") gets you into that kind of Brian May thing to my ears. Or at least that's what I was shooting for. The 22 nF setting has a nice biting midrange thing going on. Finally, the 47 nF was my attempt at the old Tony Iommi Rangemaster sound. Not a full-range boost, but very close.
The, "Secret Sauce" here is a Tesla NPN germanium transistor. The original used PNP transistors, so it had to run on battery power only or a finicky adapter. This will run on a standard Boss adapter. There's actually no provision for battery power. These transistors break up and add some grit to the signal. Like a light overdrive. It's actually my favorite effect because it voices the guitar/amp and adds a very light and transparent overdrive at the same time.
These particular transistors are very low-noise and have an extremely pleasant tone. They aren't great at reproducing high frequencies, which probably seems a bit anti-intuitive. These transistors were made for AM radios back in the day. The problem with a lot of treble boosters is that they turn the extreme high end into kind of a harsh thing. These transistors boost the upper mids that you want (well, that I want) boosted, but then run out of steam before they get to the extreme upper range that makes your head hurt (well, makes MY head hurt, anyway). They're the perfect treble booster transistor, IMO.
Some people kick these in for a solo boost, which is a good use for 'em. Brian May used to just leave his on all the time. It was a key part of his sound. These also sound great stacked with other fuzz, overdrive and distortion effects. I think they sound amazing into a Fuzz Face, but I've also had really cool experiences using one to drive an Expandora.
There is no provision for battery power. I just want to repeat that to make sure it's clear. These are DC-only operation, but they don't need any kind of finicky power adapters like most germanium pedals. The enclosure has a durable powder coated finish. Hopefully you'll enjoy this design as much as I do.