Tridacnid
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- Jun 10, 2007
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Hey all. This isn't my first build, but I'm currently attempting the "Infinity Universal Preamp" for my bass guitar. And it ain't going too well. My building has always been a mess, but it works. So far, I've gotten audio to output, but it's incredibly distorted and there's a ton of hum. The hum is generated before the volume knob, as turning it down also reduces hum. The hum is not generated by the bass pickups (threw a 1M resistor in front of the bass and it still hummed). Could my somewhat ghetto virtual ground power supply be the culprit?
The schematic (direct source): http://www.techniguitare.com/projets/ChaosPreamp/Preamp-Schems-V1.1-En.pdf
The thread that the project originated in: http://www.diystompboxes.com/smfforum/index.php?topic=74219.0
Anyways, what could be making the humming? And distortion? The distortion leads me to the power supply, because I know that an IC will distort if it isn't powered properly.
The virtual ground circuit mine is based off of (it uses the BUF632): http://tangentsoft.com/elec/vgrounds.html
EDIT: Forgot to mention that the rails in the VGC differ by about 0.1 volts without a load.
Thanks,
Tri
The schematic (direct source): http://www.techniguitare.com/projets/ChaosPreamp/Preamp-Schems-V1.1-En.pdf
The thread that the project originated in: http://www.diystompboxes.com/smfforum/index.php?topic=74219.0
Anyways, what could be making the humming? And distortion? The distortion leads me to the power supply, because I know that an IC will distort if it isn't powered properly.
The virtual ground circuit mine is based off of (it uses the BUF632): http://tangentsoft.com/elec/vgrounds.html
EDIT: Forgot to mention that the rails in the VGC differ by about 0.1 volts without a load.
Thanks,
Tri