Spyder question 15 volt output

[wavley]

So I've ordered all the parts to build a Spyder x2.  I need one of the 9VAC outs for my Boomerang, but I don't really need the other and I do need a 15VDC out for my Attack Sustain.

Is it better to use one 11 Volt secondary and the 9 Volt one for 20VAC and then regulate down to 15VDC with a single regulator or is it better to use two regulators and do both of them at 7.5VDC and parallel them for 15VDC?

A friend at work happened to find these and show them to me the morning after my wife gave me the go ahead to order parts, I ordered two sets and it looks like it will save me quite a bit of work http://www.ebay.com/itm/10pcs-LM317-Adjustable-Power-Supply-Board-With-Rectified-AC-DC-Input-DIY-KIT/111379415005?_trksid=p2045573.c100033.m2042&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20131017132637%26meid%3D52cc036eaf7b45a293aa2ed84e7bdc91%26pid%3D100033%26prg%3D20131017132637%26rk%3D2%26rkt%3D4%26sd%3D191218579434

[PRR]

> both of them at 7.5VDC and parallel them for 15VDC?

Series might be even better?

I would in general be dubious about working regs in series (or parallel!). Probably works, but they could get in a fight.

Seems you could use either 11VAC+9VAC or 9VAC+9VAC to get ~~ 26VDC, and one 7815 reg to soothe it. Mainly depends on which secondaries you need for other outputs.

One 9V winding to a voltage doubler also gets in this zone and will handle smaller currents excellently.

If you don't need dead-clean and steady or a lot of power (dunno what a Attack Sustain is), just the 11VAC rectifyed onto a big cap will give pretty near 15VDC.

[wavley]

> both of them at 7.5VDC and parallel them for 15VDC?

Series might be even better?

Oops, yes.  I was thinking about the Voodoo labs thing and remembering that they use a Y cable to get 18V from two 9V outs, in my head Y cables are parallel, but this I'm sure is wired series.

I would in general be dubious about working regs in series (or parallel!). Probably works, but they could get in a fight.

It seems like pretty common practice in multi out power supplies lately, but it just didn't seem like a good idea.

Seems you could use either 11VAC+9VAC or 9VAC+9VAC to get ~~ 26VDC, and one 7815 reg to soothe it. Mainly depends on which secondaries you need for other outputs.

I'm planning on using one of my 9VAC secondaries, but don't have any use for the second one, that's why I was thinking 11+9

One 9V winding to a voltage doubler also gets in this zone and will handle smaller currents excellently.

If you don't need dead-clean and steady or a lot of power (dunno what a Attack Sustain is), just the 11VAC rectifyed onto a big cap will give pretty near 15VDC.

The 9V and a doubler sounds like a good plan too, I don't know what the current draw of the Pigtronix attack sustain is, but it's basically just a compressor and an improved EH Attack Decay, I don't imagine that it's a lot.