Behringer ADI-21 Acoustic Preamp Pedal-- AC Adapter Issue

[Bill Sheehan]

I bought my Behringer ADI-21 acoustic preamp pedal on ebay last year, and it has been a real jewel in terms of giving a nice smooth voice to the passive piezo transducer which is installed in my uke.

So far, I have run it strictly on a 9v battery, taking care to always unplug my cable from the input jack when the pedal is not in use, so as to preserve battery life. The battery chamber is very easily accessible, and I carry spare 9V's, so even if I had a battery die during a gig, it would be very quick to pop in a new one and keep going.

So, I'm fine with just using the battery approach, but it would be nice to have the AC adapter option, just for peace of mind. However, I have tried three different AC adapters with this unit (one of which was sold to me on the promise that it was specifically known to be compatible with this pedal), and I can't get ANY of them to power the unit up.

Is it possible that the prior owner somehow managed to "fry" something in the adapter input, perhaps by attempting to use an incompatible adapter?

 

[Renaissance-Man]

Hey Bill,
I'm sorry to hear you've got a problem with your DI pedal. I bought the same one, after helping you with your performance setup last year. As you, I love mine too. My unit works with the AC adapter. My adapter's output is 9v at 300ma. The negative pole is in the center of the plug. You do need a 9v adapter with the correct plug polarity. The 300ma is just what my particular adapter is capable of delivering. The pedal actually only draws 25ma.
I'm sorry I can't offer you further guidance brother.

 

[Bill Sheehan]

Hey Bill,
I'm sorry to hear you've got a problem with your DI pedal. I bought the same one, after helping you with your performance setup last year. As you, I love mine too. My unit works with the AC adapter. My adapter's output is 9v at 300ma. The negative pole is in the center of the plug. You do need a 9v adapter with the correct plug polarity. The 300ma is just what my particular adapter is capable of delivering. The pedal actually only draws 25ma.
I'm sorry I can't offer you further guidance brother.

Thank you so much, R-M !! Your guidance is in fact immensely helpful! As it happens, I had bought a second ADI-21 pedal a few months ago as a backup, so I went over to my mini storage unit this afternoon and grabbed it. I removed the battery and tried it with the AC adapter, and it worked! In doing so, I was using a 9V adapter rated at 100ma capability (the Behringer-branded PSU-SB). I have a couple of other 9V adapters in my gear bag, rated at 500ma and 800ma capability, respectively; so, if the ADI-21 only draws 25ma (as your attachment clearly shows), then I'm guessing the 100ma-capability adapter ought to be fine. Thank you so much for the technical info and for your perspective!

 

[Wiggy]

It looks like you have the A~C covered. If you ever go to all-battery (amp and all) operation, you might consider 9v rechargeables. I've had good experience with 'zon's EBL brand rechargeable AAA and AAs. I don't know how many you buy per year or how long they last for you, but here's a charger + 4 batteries:

EBL 4 Bay 9V Lithium-ion Battery Charger with 4 Packs 600mAh 9V Li-ion Rechargeable Batteries
$29.99 shipped

 

[Bill Sheehan]

You might consider 9v rechargeables. I've had good experience 'zon's EBL brand rechargeable AAA and AAs.

Great suggestion, Wiggy. In general, do rechargeables have the ability to be used and recharged many times (say 50 ??) before they finally "buy the farm"?

 

[Bill Sheehan]

It looks like you have the A~C covered. If you ever go to all-battery (amp and all) operation, you might consider 9v rechargeables. I've had good experience with 'zon's EBL brand rechargeable AAA and AAs. I don't know how many you buy per year or how long they last for you, but here's a charger + 4 batteries:

EBL 4 Bay 9V Lithium-ion Battery Charger with 4 Packs 600mAh 9V Li-ion Rechargeable Batteries
$29.99 shipped

Just saw your edits, Wiggy. Thank you very much for that additional info on rechargeables and charging unit. I'll definitely look into it!

 

[Wiggy]

Great suggestion, Wiggy. In general, do rechargeables have the ability to be used and recharged many times (say 50 ??) before they finally "buy the farm"?

My granddaughters goes through AAs for their video game controllers like popcorn. Two years into it (they are only cycling 3 color-coded pairs) and have had no problems. They tell me they "last long" whatever that means in gaming world.

The info I found: "Rechargeable batteries typically last between two and five years and can be recharged hundreds of times."

An LIon's lifetime is shortened by running to completely dead, like in a flashlight that was left on. In your case (and in their controllers) that should not be an issue.

An example explanation: https://northeastbattery.com/whats-lifespan-lithium-ion-battery/

 

[Bill Sheehan]

My granddaughters goes through AAs for their video game controllers like popcorn. Two years into it (they are only cycling 3 color-coded pairs) and have had no problems. They tell me they "last long" whatever that means in gaming world.

The info I found: "Rechargeable batteries typically last between two and five years and can be recharged hundreds of times."

An LIon's lifetime is shortened by running to completely dead, like in a flashlight that was left on. In your case (and in their controllers) that should not be an issue.

An example explanation: https://northeastbattery.com/whats-lifespan-lithium-ion-battery/

Wow, great insight, and great info in the link that you included! Well, I see a "two-chamber" version of the EBL package as well, for under twenty bucks... Hmmm...

 

[Wiggy]

Attention Bill!

I'm reading that specifically with 9v rechargeables they can/will have low voltage and make RF noise with pedals and active pickups. I almost bought some until I read the reviews from electric guitar and bass players. So, stay with your non-rechargeable 9Vs.

Google:
rechargeable 9v batteries noisy guitar pickups and pedals

<edit> For now, it's Harbor Freight Magnum Alkaline 4-packs. 7 bucks.

 

[Bill Sheehan]

Attention Bill!

I'm reading that specifically with 9v rechargeables they can/will have low voltage and make RF noise with pedals and active pickups. I almost bought some until I read the reviews from electric guitar and bass players. So, stay with your non-rechargeable 9Vs.

Google:
rechargeable 9v batteries noisy guitar pickups and pedals

<edit> For now, it's Harbor Freight Magnum Alkaline 4-packs. 7 bucks.

THANKS, Wiggy, for that followup!!