Question about powering two pedals in one box

[mr.adambeck]

I'm planning on going all True bypass, except for two buffers.  I was going to put the two buffers in one enclosure, one buffer being at the start of my chain, then going through all the effects and having the line come back in to the second buffer and then to the amp.  They would be powered by my daisy chain, not from a battery.
Do I need to attach two, separate 9 volt adapters to the enclosure, or can they both run off of the same supply?  If they are coming from the same supply, it doesn't get less power, right?  Or am I confused?  Thanks!

[sean k]

Just de-couple the power at each opamp or section in that the power in to each buffer section has it's own .1uf and 10-100uf caps as close as possibble to the opamp. I have them above pins 1 and 8 then go down the centre between the pins to make the bias with the two resistors and another cap so the whole power supply is above and below the opamp and the signal stuff can go to the sides.

This way you have everything on its own + and - supply and only two wires going in. It works with multiple sections on one board because the signals on the + are smoothed at each section and the - is kept to each section then goes to one point which all the sections share.

Power used depends on the load resistance and if you halve the load, which happens if you add two sections, the current draw doubles so you just make sure you have enough on tap. 

[mr.adambeck]

whoa, whoa whoa, slow down.  I'm way too much of a noob to understand that.  I'm making the buffer build suggested in beavisaudio.com's buffer tutorial.  What do I need to change (specifically?) in order to do what you are saying?

[tempus]

Why do you need 2 buffers?

[mr.adambeck]

Tempus - according to the article here : http://beavisaudio.com/techpages/Buffers/  "A buffer at the beginning of your chain of true-bypass pedals, and perhaps one at the end is a good thing"
I was basically going to do that, but put both the buffers in one enclosure.  I'm just trying to figure out if I need two separate dc jacks, or if I can power both off of one.

[tempus]

I figured that must be where you got that idea. The thing is though (and this depends of course on which pedals you're actually using) if you have a buffer at the start, you probably don't need one at the end, since most pedals already have a low impedance output (which is what your buffer provides) If you've got your pedals bypassed, you don't need one at the end, because you've already got one in your signal chain at the start - IOW you don't need 2 buffers in a row. Again, it depends on the setup, but you could save yourself the hassle and be 'more true bypass' if you didn't have the 2nd (probably redundant) buffer.

Which buffer are you going to build? You may be able to use just 1 tap for 2 buffers if the buffer doesn't draw much current.

[GibsonGM]

+1, Tempus.   If you are all True-bypass, you might not need a buffer at all!  Are you experiencing loss of high freq's with everything off?  If not, you're fine.  Geez, I run 4-5 effects, all T bypass, and don't need any buffers at all....unless you just want to 'condition your signal', in which case 1 at the beginning of the chain would work well.  I don't like altering my input signal, though (sort of like having a compresser in the line, yuck).

If you're set on having a buffer, I'd suggest building a temporary one on a breadboard first and then running it into your pedal chain, see what effect it has on your sound.   

[Barcode80]

wow, all these posts and no one directly answered the OP's question??

yes, you can wire them both to the same dc jack and only have one jack in the enclosure. Just tie each buffer's +9v and ground together.