Wall plug voltages

[pete.young]

I've been having some problems with my pedal board recently and have been trying to find the source of the trouble. Pedal arrangement is like this:

Korg DT10 -> EBS Multicomp -> Double bypass loop -> Amp

Loop 1: EBS Octave -> Bass Big Muff -> Korg G5 analog synth
Loop 2: Boss C5 chorus

Power is provided by a Dunlop DC Brick. All pedals are 9V except for the chorus, which is 18V. All the cables are relatively new.

The problem is when I switch in loop 1, I have an intermittent drop in gain. Sometimes none at all, sometimes 50% , sometimes complete silence.

I don't think the problem is with the Bypass loop pedal - there's essentially nothing in it except for switches, which either work or not. This got me thinking about the power supply voltages so I whipped out the multimeter - 9V outputs are giving 8.7V, 18V outputs are giving 16.5V . The DC Brick wall wart puts out a nominal 18V which goes straight through to the 18V outputs.

I stumbled across another 18V transformer - output 23 V. The 9V transformer that came with the G5 puts out - 14.4 Volts !

So how sensitive are these pedals to voltage drop? I admit I'd be thinking about changing a battery that read only 8.7 volts.

Comments, questions, thoughts?

[Protium]

IME analogue pedals are affected less by a drop in voltage (to a certain point) but digitals need to be run close to 9V. They'll work to a point but then completely cut out after that, whereas the analogues will continue operation albeit with strange effects

I wouldn't trust a battery reading 8.7V at a gig, try taking out any digital effects (the EHX and Korg are analogue afaik, is the EBS octave digital?).
Another idea - is there enough juice from the power supply (in terms of mA) to power all the pedals?

Edited December 7, 2009 by Protium

[Kev]

the korg is most certainly digital, and im pretty sure the rest are all analogue.

Check the current draw as Protium said, the G5 will suck a lot.

[pete.young]

[quote name='Protium' post='677241' date='Dec 7 2009, 09:33 PM']Another idea - is there enough juice from the power supply (in terms of mA) to power all the pedals?[/quote]

I thought so, but apparently not! The DC Brick supposedly has an output of 1000 mA. But, read the small print.

The maximum current it will deliver to all the 9V outlets is a puny total of 375 mA. The adaptor for the G5 is rated at 600mA, so I think you guys have hit the nail on the head. I'll try running the G5 on it's own power supply and run the rest of the board off the DC brick and see where that takes me. Shoulda bought a Diago!

Many thanks for all the help, it is much appreciated.