anevilspar7an
Well-known member
One mod you could do to get more tonal variety from your preamp tubes is to do a Hi/Lo input impedance switch. Could be used to dial in vintage and modern basses.
A DIY 100 watt tube bass amp
- Thread starter Passinwind
- Start date
Passinwind
Well-known member
Right now input impedance is ~100k. The plan has always been a 3 or 4 way rotary switch for that, you can see the knob labeled "Imp" at far left in the first pic. But both of my basses are active and I almost never use bypass mode on the one that even has a bypass. I do own a couple of passive guitars though, so certainly worth a try for them. I finally tried using my Spark 2's line out as a guitar front end a few days ago, which works plenty well enough to keep me happy until I get around to a proper guitar amp build.
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Passinwind
Well-known member
Dust cover from Coveramp in Quebec:
Fiits like a glove and seems very well made in general.
Fiits like a glove and seems very well made in general.
Passinwind
Well-known member
It's been a busy couple of weeks working out pedals for acoustic and electric guitar so I can enjoy this amp with more than my basses. That has gone surprisngly well, and it was nice to have an excuse to build a few more PPCB projects up. Here's how my guitar board is shaping up so far:
So: Kliche (Klon) Mini --> PW3B-LPF EQ (for clean electric mostly) --> Crystal Lettuce Silver --> Mahanaya (Zendrive) OD --> PW/Cabintech delay/verb/chorus. So a hard clipper drive, opamp AIAB, and soft clipper drive, which turn out to all play pretty nicely with each other in various combinations. Power underneath, via Cioks C4 and an Iniu power bank. Green pedal at top right is for acoustic guitar. Smaller new delay box in process - a 1590XX for now but can probably go to 1590 BBS with the newer CT digital BBD board when I re-up. This all sounds absolutlely badass through the new amp, even just through a modest 1 X 8 cab. I'm sure I'll get to designing my own drive pedals soon enough, but I still want to work through a few more of the classics via the huge PPCB selection. And of course all the keepers will get reboxed in due time.
So: Kliche (Klon) Mini --> PW3B-LPF EQ (for clean electric mostly) --> Crystal Lettuce Silver --> Mahanaya (Zendrive) OD --> PW/Cabintech delay/verb/chorus. So a hard clipper drive, opamp AIAB, and soft clipper drive, which turn out to all play pretty nicely with each other in various combinations. Power underneath, via Cioks C4 and an Iniu power bank. Green pedal at top right is for acoustic guitar. Smaller new delay box in process - a 1590XX for now but can probably go to 1590 BBS with the newer CT digital BBD board when I re-up. This all sounds absolutlely badass through the new amp, even just through a modest 1 X 8 cab. I'm sure I'll get to designing my own drive pedals soon enough, but I still want to work through a few more of the classics via the huge PPCB selection. And of course all the keepers will get reboxed in due time.
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Passinwind
Well-known member
I wired in the four way impedance switch last week just before going to visit my primary luthier client down in Oregon. He does quite a few "boutique Fender-ish" builds and I wanted to see how my amp might deal with that. The switch did help and it also reinforced that with my designs going as high as 1 Meg is rarely needed or that beneficial, for bass at least. I went out of my way to optimize for uber hifi active instruments though, and so it was no surprise that those sounded the best, although going a bit above 100K did bring some nice things in many cases. A useful enough feature to be a keeper in any case!
So far the predominant reaction in testing has been "killer studio amp." I'm going to recruit a couple of pro friends to leverage that into some demo recordings, because ironically enough I don't really enjoy the recording process at all myself, plus I don't even own a fretted bass.
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