Chaining power supply

[curtcurt55]

I want to make a rack mounted unit with a few different pedals all in one unit.

I'm not sure how to wire it so that I can power all the pedals from one single wall wart.

would it be as simple as going negative to positive and just connecting the first positive and last negative to a power supply jack?

thanks everyone!!

ps, this is my first post.

[Ice-9]

Chain linking the supply to all pedals would work but may cause some ground loop hum, you will have to try it to see. As for wiring the psu chain it should be wired in parallel, ie from the supply jack + to all effects positive, supply jack negative to all effects negatives.

THIS IS ASSUMING ALL YOUR EFFECTS ARE 9V DC and not a mixture of dc and ac powered effects or positive earth type effects.

[GibsonGM]

Chain linking the supply to all pedals would work but may cause some ground loop hum, you will have to try it to see. As for wiring the psu chain it should be wired in parallel, ie from the supply jack + to all effects positive, supply jack negative to all effects negatives.

THIS IS ASSUMING ALL YOUR EFFECTS ARE 9V DC and not a mixture of dc and ac powered effects or positive earth type effects.

+1

Running them + to -   and so on, will result in ADDING the voltages.  We don't want to do that

In parallel, your effects will see the same voltage as the power supply.  They will all draw different currents. It's your job to make sure the current draw of all of them doesn't exceed your supply's ability to deliver!

[curtcurt55]

Oh great! So how would I know if the current draw exceeds my supply?

I will probably have 5 effects in this unit, all usually wired to a 9v battery. I plan on replacing the battery clips with this chaining idea, if it works how i hope it will, it will essentially be a glorified preamp with an eq, a booster, and a compressor.   

[Ice-9]

Running the positive to negative in series through the effects would actually result in a series of short circuits as the ground in the instrument connections would short out the PSU supply.

To work out the total current draw, if you have a DMM you can measure each effect by setting the DMM on Ma and connect one on the battery conections to the battery snap while holding one of the Meter leads to the unconnected battery and the other meter lead to the unconnected battery snap connection. With the pedal activated (led on)  you will get a current reading on the meter.

Alternatively tell us what effects you intend to use and forum members may know appx current drain of each effect.

[davent]

I've a small box that i use to  daisy chain the power to an effect i want to measure the current draw of. Puts a 1r resistor in series, measure the mV drop across the resistor for the mA draw of the effect.

[Tony Forestiere]

I've a small box that i use to  daisy chain the power to an effect i want to measure the current draw of. Puts a 1r resistor in series, measure the mV drop across the resistor for the mA draw of the effect.

That is brilliant.  (Now where did the light-bulb emoticon go?)
Very nice execution for a defined purpose.