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jugglindan
07-06-2020, 05:39 PM
Curiosity got the better of me, so I hooked a multimeter in between a battery and some effect pedals. Once I remembered to change the lead from the voltage/resistance socket, I got the following:



Pedal
mA Off
mA On


Barber Compact Direct Drive Clone
3.8
12.9


BYOC OD-2
4.9
8.2 (both boost and TS engaged)


Phase 45 clone
5.7
9.2



I tried to test the Xtomp mini (a digital pedal), but it wouldn't power on from the battery.

And then I got bored, so didn't test any others. Might update this thread later if I ever get around to it.
For most of those pedals, the increase in draw when the pedal is on looks suspiciously like the extra current draw of the indicator LED. There's not really anything else changing.

Bakersdozen
07-06-2020, 06:07 PM
Curiosity got the better of me, so I hooked a multimeter in between a battery and some effect pedals. Once I remembered to change the lead from the voltage/resistance socket, I got the following:



Pedal
mA Off
mA On


Barber Compact Direct Drive Clone
3.8
12.9


BYOC OD-2
4.9
8.2 (both boost and TS engaged)


Phase 45 clone
5.7
9.2



I tried to test the Xtomp mini (a digital pedal), but it wouldn't power on from the battery.

And then I got bored, so didn't test any others. Might update this thread later if I ever get around to it.
For most of those pedals, the increase in draw when the pedal is on looks suspiciously like the extra current draw of the indicator LED. There's not really anything else changing.

Interesting investigations. I had always assumed that a non-buffered true bypass pedal wouldn't be drawing anything until the circuit was engaged. Your previous investigations on the Joyo and this confirms that they all still draw an amount even whilst in bypass state.

DrNomis_44
07-06-2020, 06:15 PM
Some analog delay pedals based on BBD (Bucket Brigade Device) technology tend to be a bit current-hungry.

jugglindan
07-06-2020, 06:15 PM
Yeah, I am not sure why they are wired up like this. Maybe it prevents popping that might occur if the power is switched on and off.

To be fair, it's a tiny amount of power though.

Bakersdozen
07-06-2020, 06:17 PM
Oh yeah totally . Just funny how your mind perceives how you think things would work.

jugglindan
07-06-2020, 06:28 PM
Some analog delay pedals based on BBD (Bucket Brigade Device) technology tend to be a bit current-hungry.

Sadly I don't have one of those to measure. I do plan a PT2399 based delay later this year. Just can't decide between building a Mad Professor Deep Blue Delay, or the closely related Earthquaker Disaster Transport Jr.

The hungriest pedals I have are all the digital ones. They draw 2 to 3 orders of magnitude more power.

McCreed
07-06-2020, 07:00 PM
A few years ago I went through a similar process of compiling a list of all the pedals I owned.
I didn't measure all of them so some as stated by the MFR and some recorded by me (as noted on the list). However I didn't do a full comparison of "stated" vs "measured" mA.

I haven't updated it in quite a while, and I definitely have acquired more pedals since then. Maybe I'll take the time and do those so I can get them on the list. I only did it so I could keep an eye on total current draw vs what my power supply could handle.
I've been using a 2A supply for a long time and never have come close to that. (even if I turned them all on simultaneously)

My main pedalboard regularly consists of 10-11 pedals.
Which makes me think... have we had a "show us your pedalboard" thread here???

Anyway, here's the list if anyone is interested. (Sorry had to save as .txt to fit file size)

Simon Barden
07-06-2020, 09:30 PM
Have you tried measuring current draw with a guitar signal going through, rather than a simple on/off test? I would have thought that the drives at least would draw a bit more when actually amplifying a signal.

jugglindan
07-06-2020, 09:56 PM
Have you tried measuring current draw with a guitar signal going through, rather than a simple on/off test? I would have thought that the drives at least would draw a bit more when actually amplifying a signal.

I agree, but didn't test that. However, my figure for the OD-2 is in line with reported draw for various tube screamers (http://stinkfoot.se/archives/852).