I'm getting 12v-13v from all my 9v power supplies??!

[auden100]

That's pretty much it. I'm debugging a pedal, checking voltages, and notice that everything is coming out 13v. So I change power adapters. Again 13v. So I get another. Same thing. I'm not sure how this is possible, and its consistency is making me think either I'm doing something wrong, or there's something wrong with my DMM. I've been measuring the voltage on the circuit and directly from the AC adapter. Then I checked a couple of 9v batteries to compare, and they each read 8v or 5v, roughly. How is this possible?

[earthtonesaudio]

Unregulated power supplies put out their stated voltage only at the stated current.  At lower currents, they put out higher voltage, and vice versa.

[auden100]

ah. I didn't realize. Thanks for the quick response, Alex. Now on with the debugging!

[zombiwoof]

I found out that with the "9-volt" adaptors that come with the BBE pedals, and was told they are unregulated (and they put out a little over 13 volts unloaded).  In comparison, a Danelectro 9 volt adaptor puts out right around 9 volts (I think it was 9.6 volts, similar to a new battery).  The good thing about the BBE adaptors is that I found that they would power my old ACA-powered Boss pedals.  The old ACA adaptors were unregulated and put out over 12 volts, and there was circuitry in the pedal to knock that down to 9 volts.  You can daisychain the ACA Boss pedals with other pedals in a 9-volt chain and they will work correctly, but by themselves they need the unregulated adaptor unless you mod the pedal (bypass the regulating circuitry in the pedal).

I'm surprised that BBE is taking this approach however as most pedals these days use regulated power supplies.

Al

[fatfoohy]

I can relate to this, i picked up a power supply at a yard sale, and after looking at ( it was making all my pedals act funny) i discovered it was putting out 13 volts, even while connected to one of my pedals while it was on. I proceeded to take out to my work bench where i have been too lazy to put a voltage regulator on it.