I have one of these and was wondering about some mods that could be made to it. Anyone have any?
What about "univibing" it?
Sigh. The sixth reply was a fulminating case of BUMS.
Why exactly do you want to mod it? Is it that the sound is not very exciting and you think it could be turned into a new monster sound? That won't be the case in general.
"Univibing" a phaser can be done to any phaser. Whether you want to or not is subject go some question. The whole issue of how the univibe does phase stage location versus the rest of the phasing world has finally gotten settled. It was actually settled in the mid 70's, but I didn't get to read the paper until almost 30 years later.
What JC calls "univibing" is staggering the values of the phase caps to spread the phase shift range over the middle of the audio spectrum. What this does in the univibe is to give a better vibrato sound by making the apparent frequency shift be spread around over the audio spectrum instead of concentrated in one place. This is a big deal when one of the switch positions is marked "vibrato". It's less of a big deal when what you want is phasing. It moves the phase notches out to ideosyncratic positions that may or may not be pleasing and diffuses the phase sound. There were a couple of papers on this in the JAES in the mid 70's, and the upshot is that the best phasing sound comes from identical time constants in the phase stages. But as I'm fond of saying "What exactly do you mean by 'best'?" There can be no "best".
Sorry - you pushed my button.
No, I don't have any mods for it.
The other difference I find clever is the presence of Q6. Q5 does the usual job of lifting/making the contact to feed the wet path to the mixing stage. Q6 is there to compensate volume levels and achieve level balance between effect and bypass modes. It does this by changing the resistance of the ground leg from pin 2 of IC2. Neat.
Yeah, I did like that one. Once you go to cold switching, it's good to remember that you can switch ANYTHING when you switch operational modes. It's well worth remembering.
I think if I was designing a phaser, I'd go for a few fixed phase shift stages before the variable phase line, maybe a few fixed stages in parallel, and probably two phase lines in parallel, but driven from synchronized but not identical LFOs. Something like a 3 to 4 relationship maybe. And allow much of the assemblage to be switched in or out with signal routing on the board.
OK, I guess what I'm really doing now is modding. Busted.
So my mod for the PH-1r goes like this: Take four of them. Neuter the LFO on two of them. Disconnect the internal feedback on all of them. Run one in series with one of the non-neutered ones, and another in parallel into the final mixer, which you will also need. Run the output of the two live phase stages back through a pot to the input of that section. Now put switching in/out on all of them, and add synchronized LFOs on the two active phase lines. Or, to taste, just leave the LFOs non-synched and let the human do it.