Cgs synth

ok after doing some research ive realised i can get a dc plug pack,
then run that in to a rail splitting circuit and from there in to
linear regulators. i was going to get a 24vdc power pack that would
deliver 500ma. but i have no idea how many ma the synthacon (and
lm3915 circuits) would draw. im guessing the two lm3915's with their
LED bars would chew up 100ma, and i was going to run it off the power
pack directly.

so i wanted to know how much current you guys think the synthacon
would draw?

i ask because the obvious choice for rail splitting before regulation
would be a TLE2426 (i have a few left over from my HP amp projects),
however this can apparently only really handle 20-40mA loads. i have a
pimeta headphone amp that i built, it utilises a TLE running 3 buf
634's and 3 opa627's. i run it off two 9v batteries giving 18v. so a
different scenario but the TLE seems to do ok there.....the schematic
is here http://tangentsoft.net/audio/pimeta/misc/schematic1.pdf

the next option for parts i already have would be to create a virtual
ground circuit with a buffer (i have buf634's) that can apparently do
up to around 150mA. I'm sure there won't be ANY problems with 150mA,
but I have made TLE circuits in the past but not buffer based rail
splitters.

so my thoughts on a powersupply are:
24vDC plug pack -> rail splitting circuit -> regulation circuit
(7912/7812).

the other option is:
25vDC plug pack -> regulation circuit (lm317) -> rail splitting circuit.

what do you guys think about these options??

thanks

sean :)

>so i wanted to know how much current you guys think the synthacon
>would draw?

not much at all. I haven't measured it, but it would be under 50ma.

>the next option for parts i already have would be to create a virtual
>ground circuit with a buffer (i have buf634's) that can apparently do
>up to around 150mA. I'm sure there won't be ANY problems with 150mA,
>but I have made TLE circuits in the past but not buffer based rail
>splitters.

possible.

>so my thoughts on a powersupply are:
>24vDC plug pack -> rail splitting circuit -> regulation circuit
>(7912/7812).

forget it. You'd need 30 volts to do this. There is too much drop in the
regulators.

>the other option is:
>25vDC plug pack -> regulation circuit (lm317) -> rail splitting circuit.
>
>what do you guys think about these options??

Better option - 15 to 18V AC plugpack through a pair of half-wave rectifiers
into 78xx and 79xx.

See here.
http://www.cgs.synth.net/modules/cgs46_sba.html
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Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
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