Question about Daisy-Chaining 12v Boss Pedals

[Jjango]

Hi, folks.

After decades of powering my effects pedals with batteries, I finally decided to get an effects board recently.

After reading up on TalkBass for a bit, I discovered that each of my three 1980s-era Boss pedals require a 12 volt power supply - not a 9 volt.

These are my pedals:

However, the power supply on my pedal board only has ONE 12 volt outlet:

So here's my question:

Can I power all three pedals from the effects board by using a Daisy Chain cable like this?

https://www.amazon.com/Guitar-Effect-Supply-Splitter-Adapter/

Thanks in advance for any assistance you can provide!!

 

[smogg]

It should work fine as long as the combined power draw of the three pedals is less than the output of the 12v outlet.

 

[Jjango]

Thank you, smogg!

According to this list, the power draw of my pedals is:

PEDAL	CURRENT DRAW
BOSS OC-2 Octave	4mA
BOSS PH-1r Phaser	<5mA
BOSS CE-3 Chorus	13mA

So the combined power draw of my Boss pedals is 22 mA, and my effects board offers 200mA on the 12v power socket.

I should be good to go then, correct?

 

[whoismarykelly]

Daisy chaining ACA Boss pedals defeats the voltage dropping circuit so you should run them off a 9V tap rather than a 12V tap.

 

[smogg]

@Jjango .
imo you can trust advise from @whoismarykelly. He knows his stuff. Still diggin' my MBD2.

 

[Jjango]

Thanks, will do, @smogg! And thank you to @whoismarykelly!

---

To expand on what whoismarykelly said, if you daisy-chain a Boss pedal that requires a 12v power supply with any pedal that requires a 9v power supply, it “deactivates” the part of the Boss 12v pedal's hardware that insists on having 12v.

Since I'm explaining this so incredibly poorly, here is a much better explanation for anyone who might read this thread in the future:

When powering a Boss ACA (old-style 12v) pedal from a 9v PSA adapter, you will probably notice that the LED barely lights up. This is normal and expected behaviour, since the 9 volts fed to the pedal really is too little – it wants roughly 12 volts on the adapter input, remember? But when the power is being provided via a daisy-chain, with other 9v PSA pedals connected to the chain and with signal cables connecting them, the LED suddenly lights up as normal…

What happens is that all the pedals in the daisy chain share a common ground, which bypasses the voltage limiting components in the 12v ACA pedal(s), causing the pedal to receive the full 9 volts. This trick works with any power supply where the outputs share a common ground – daisy chain setups, DC Brick etc.

Boss ACA & PSA – what gives? – stinkfoot.se

stinkfoot.se

 

[devnulljp]

To expand on what whoismarykelly said, if you daisy-chain a Boss pedal that requires a 12v power supply with any pedal that requires a 9v power supply, it “deactivates” the part of the Boss 12v pedal's hardware that insists on having 12v.

Is this still true if all 3 pedals daisychained together want 12V? I've done this with my old OC2 and daisychained to my (9V) tuner. Guess I should try with some other old Boss pedals and report back.
(@whoismarykelly ?)

 

[Jjango]

Is this still true if all 3 pedals daisychained together want 12V? I've done this with my old OC2 and daisychained to my (9V) tuner.

Mind you, I am absolutely NOT an expert in this stuff at all. Just the opposite, in fact.

But from what I've read, at least one of the pedals needs to be a 9v pedal. Without it, there's nothing to “convert” the 12v to 9v.