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average joe
03-30-2010, 09:13 PM
Well I built a simple 8 bit r/2r ladder dac and attached it directly to pins 0-7. Plan is to write a ?simple? ASDR to be triggered by external events. I need to generate 0 -5v cv for Vca hacked from an Alesis Microlimiter. I want to use the bs2 to generate cv based on picking dynamics of my guitar. Any thoughts? Spare parts project once again. Has anyone played with anything like this?

davejames
03-30-2010, 11:58 PM
Hey Average!

Interesting project you have.

What ever happened with the buffer project from last year?


DJ

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average joe
03-31-2010, 08:11 AM
Hey DJ, I had to put that project on the back burner. SNR was 20db with a noise floor of -40db,unbuffered pickup noise floor was about -65db. The added noise was due to poor power supply isolation, ground loop issues. After looking at the project again I've decided I need new wire, thinking cat-5 to run balanced signal for each pickup. This should fix the ground loop problem. Also working on new power supply. I'm going to play with it more when I finish building my new guitar. Right now I'm just using a simple 1 in, 3 out 4053 based switcher. Works good. Clean. Will post schematic if interested. Any thoughts on the new project?

davejames
04-01-2010, 12:33 AM
AJ,

Yeah - from those numbers, it does sound like a "rethink" is in order. High impedance, low signal level circuits can be a bear. Yes, please, schematic for the simple switcher.

I have not done anything remotely related to your current project. With that said, I'm mildly concerned that that BS2 would be fast enough to convert audio in this fashion. That's definitely not a "no - won't work"; I'd have to sit down and play with the circuit and see the results (something I'm having to do in my own current project). Schematic for this please?

DJ

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