Change from Battery to Wall Wart Power Supply (SLMS)

[El Mop]

Do I have to take C16 and C18 out if I want to change from Battery to
Wall Wart Power Supply?
Are any other changes necessary?
Thx in advance.

[Feifer]

There's not enough information here to reply.

[El Mop]

What information do you need?

PS: OH, I´m talking about the Sound Lab Mini Synth! Surely that is what you mean. My fault. Sorry.

[Feifer]

Ah, I see where it is now. Short answer is no, you don't have to take those out. In fact, a little extra rail filtering is never a bad idea. If they're already in I'd say just keep them. As far as other potential changes, are you going from 9 to 12 volts?

[El Mop]

Yes, I´m going from 9 to 12V.

[Feifer]

So it's not really necessary to change this, it'll still work just fine, but I found that going to 12V will give you too much frequency range so that a good amount of your pot will be wasted on too low to hear and too high to hear frequencies. You might want to increase R50 and R52 as well as adding a resistor to the negative side of R55 and R58. You'll have to play with them to get the range right, but it really helps when you're trying to tune it in.

I noticed a similar problem with the VCF, but now I can't remember if it gave too much or too little cutoff and res. I ended up not fiddling with it but you might want to play with the resistors on either side of those pots too.

Another change to that project that I did, and this is just personal preference and actually has nothing to do with the voltage change, is put the LFO output pot to ground instead of -V. It makes it symmetric around your preset frequency which I think is nice.

[El Mop]

Thanks.
Also for that LFO-Pot-Thing. Sounds good to me either.
I will try this.

[alieneYe]

hey there,

i recently changed my soundlab to 12 volts. i had to add a 47K resistor to the Filter cutoff pot on the negative voltage side. without it the filter cut completely out when the pot reached about the "nine o'clock" position and had not much effect from that position to completely anti-clockwise

also had to change R56 & R59 from 1M to 1.5M to get closer to 6 octaves of tuned Oscillators