freshtapescent
Well-known member
- Joined
- Jan 25, 2014
- Messages
- 46
Gentlemen-
I have some vintage preamps that don't and won't have phantom power locally enabled. Thusly I'm building a 12 channel external phantom supply that will sit next to my snake, and only condensers and mics that need phantom will have to go through it. That way my tube mics, dynamics and ribbons don't have to see any superfluous circuitry. I've got a Power One linear +48 supply, and will complete the rest on perf/vero. I've poured over the net for a few days trying to figure out the best sounding but safest way to protect my mic preamps. Please have a look and call BS if you see anything you don't like. Electrolytics in the signal path will be Nichicon MUSE KZ. Switch provides a path back through 6k8 to drain caps before disconnecting mics. R4/R5 limit current through Zeners in the case of a mic disconnecting while phantom is still on. R6/R7 drain off leakage current. Back to back zeners on both legs to save preamp input circuitry. R1/C1 Local decoupling will be on each channel to soften the snap to a thump when the global switch is thrown.
I have some vintage preamps that don't and won't have phantom power locally enabled. Thusly I'm building a 12 channel external phantom supply that will sit next to my snake, and only condensers and mics that need phantom will have to go through it. That way my tube mics, dynamics and ribbons don't have to see any superfluous circuitry. I've got a Power One linear +48 supply, and will complete the rest on perf/vero. I've poured over the net for a few days trying to figure out the best sounding but safest way to protect my mic preamps. Please have a look and call BS if you see anything you don't like. Electrolytics in the signal path will be Nichicon MUSE KZ. Switch provides a path back through 6k8 to drain caps before disconnecting mics. R4/R5 limit current through Zeners in the case of a mic disconnecting while phantom is still on. R6/R7 drain off leakage current. Back to back zeners on both legs to save preamp input circuitry. R1/C1 Local decoupling will be on each channel to soften the snap to a thump when the global switch is thrown.