I'm curious... how have others here who've made their own amps powered their preamps... I'm thinking of a 3886 chipamp and I'm considering my options for preamp, transformer, etc... separate transformer, or one with extra secondaries...etc.
No one? I'm just curious... looking for ideas... transformers (scavenged/bought)... powersupply ideas, etc.
It seems the best idea is a small secondary transformer, its easy, cheap and supposedly helps cut out unwanted noise.
Check out the preamp schematic in ESP's Project 27 (http://www.sound.westhost.com/project27.htm). He uses a power resistor and a Zener diode. That's how I'm powering my preamp.
I see... yes, that's the sort of solution I was looking for... How would you change the components if you needed a different voltage, I wonder?
Did you decide on a preamp, turbo?
Quote from: Stompin_Tom on August 31, 2006, 11:02:34 AM
I see... yes, that's the sort of solution I was looking for... How would you change the components if you needed a different voltage, I wonder?
Did you decide on a preamp, turbo?
Well, I have two preamps built and ready to go. The Sans Amp GT-2 from www.tonepad.com which is a converted stompbox preamp and I've also built the Project 27 preamp from ESP. One of these should work I'm guessing. I'm hoping the Sans Amp preamp works like I want it to. I need to find a nice high gain preamp to play with as well. Anyone have suggestions?
You can change the resistore to suit the amount of power you need. The schematic above is set up for about 50 milliamps at +-15v. 35V / 680 = .0515. If you need more power than that, you can drop the power resistor value some and if you need to change the voltage, use a different value Zener diode.