So I've got one of these B1 Korg boards on it's way to me from Leeuwarden. I'm excited to try it out, but I didn't realise I need an oscilloscope or analyser to adjust the Nutube. All I have is a basic multimeter!
Are there two points on the board that I can measure between to get an idea of the voltage offset? Failing that, roughly what position should the pots be in for neutral, or about 9v (that's about 1.5% distortion, or Nelson's preferred / suggested setting right)?
I'm not going to buy a scope, so I might as well try by ear, but it'd be good to have a rough starting point.
Are there two points on the board that I can measure between to get an idea of the voltage offset? Failing that, roughly what position should the pots be in for neutral, or about 9v (that's about 1.5% distortion, or Nelson's preferred / suggested setting right)?
I'm not going to buy a scope, so I might as well try by ear, but it'd be good to have a rough starting point.
No scope needed. Just a DMM. Follow Nelson's adjustment procedure from his article on the Firstwatt website.
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Ah ha! Thank you, that's really helpful. I was just comparing both circuits and board layouts trying to figure out the points.
So we're looking for about 9.5v at T7 & 8. That's powered up but with no input signal?
So we're looking for about 9.5v at T7 & 8. That's powered up but with no input signal?
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So, only three years later I get around to trying this out.
Can I add jumpers to the output switch pins and volume pins to have it hardwired to channel 1 and 100% volume? Or maybe I can add a certain resistor value across the volume pins?
Basically just want to add it between a source and an existing preamp to see how it sounds.
Can I add jumpers to the output switch pins and volume pins to have it hardwired to channel 1 and 100% volume? Or maybe I can add a certain resistor value across the volume pins?
Basically just want to add it between a source and an existing preamp to see how it sounds.
