Anyone ever tried a 1176 on a dual 15V supply?
It was just that I could use another comp, I like the 1176 and had 4 dual 15V supplies and no way to go for the -10/+30V. So there was a challenge to make a nice comp with a sound with the parts I had lying around.
Today I got this prototype running and it even sounds good to my ears.
The input is a THAT1240 line reciever.
After which I kept the discrete first gainstage and rectifier.
I used a very simple DOA to drive an OEP 2:1 output transformer. Like the Jensen 918.
Of course no spare Sifam meter, and that's where I'm stuck now.
I used an electronic opamp based rectifier for a $7,- meter, which works fine for metering output level... Problem occurs in GR-mode... I think I have to look over my PCB layout and design around the TL071...Because the TL071 driving the rectifier seems to act like a comparator.
I can see the GR on the meter, but i swings full left or right and is untrimmable. Not that it's over sensitive, more digital, like yeah, gain reduction is taking place or no you're below threshold...
I changed some R's because the circuit around the metering is fed +15V/-10V instead of +30V/-10V, but that was mostly guesswork, I changed the 4k3 to 2k1 aswell as lowering the 10k under the 'zero-adjust' trimpot... I think I might have to lower/half the 10k source resistor of the control-fet...
Well I have a good night sleep and will post schematic/pcb-layout if I get the GR-metering to work if anyone is interested.
It was just that I could use another comp, I like the 1176 and had 4 dual 15V supplies and no way to go for the -10/+30V. So there was a challenge to make a nice comp with a sound with the parts I had lying around.
Today I got this prototype running and it even sounds good to my ears.
The input is a THAT1240 line reciever.
After which I kept the discrete first gainstage and rectifier.
I used a very simple DOA to drive an OEP 2:1 output transformer. Like the Jensen 918.
Of course no spare Sifam meter, and that's where I'm stuck now.
I used an electronic opamp based rectifier for a $7,- meter, which works fine for metering output level... Problem occurs in GR-mode... I think I have to look over my PCB layout and design around the TL071...Because the TL071 driving the rectifier seems to act like a comparator.
I can see the GR on the meter, but i swings full left or right and is untrimmable. Not that it's over sensitive, more digital, like yeah, gain reduction is taking place or no you're below threshold...
I changed some R's because the circuit around the metering is fed +15V/-10V instead of +30V/-10V, but that was mostly guesswork, I changed the 4k3 to 2k1 aswell as lowering the 10k under the 'zero-adjust' trimpot... I think I might have to lower/half the 10k source resistor of the control-fet...
Well I have a good night sleep and will post schematic/pcb-layout if I get the GR-metering to work if anyone is interested.