# Basic question about power supply

#### gsucher

##### Newbie
Hi, I'm really here just to ask a very basic question. I have a rechargeable Bose speaker which takes a 17-20V, 1A current from its power supply to charge its battery(ies). However, I lost or otherwise cannot find the transformer. So like most, I have more than a dozen orphaned black bricks floating around the house. Assuming the correct plug, they range from 5V and 600mA to 12V and 3A. Basically I'm down to 2 choices, both 12V (less than what the speaker takes) but one is 1A one is 3A. Basically my question is would either 12 V work but just take longer? And would the 3A be dangerous or with the slightly lower voltage be OK? Please excuse my profound ignorance. I never read my father's electrical engineering book he had on his shelf. And TIA.

#### Audioguru

If the 17-20V is DC then the replacement power supply must have the correct plug and the correct polarity.
12V is so much lower than the 17-20V it needs that it probably will not charge the battery. A laptop computer uses a 19VDC charger that will work. The charger circuit in the speaker will take as much current as it needs, even if the power supply can produce 1000A.

#### gsucher

##### Newbie
If the 17-20V is DC then the replacement power supply must have the correct plug and the correct polarity.
12V is so much lower than the 17-20V it needs that it probably will not charge the battery. A laptop computer uses a 19VDC charger that will work. The charger circuit in the speaker will take as much current as it needs, even if the power supply can produce 1000A.
Thank you. The 12V actually did charge it *somewhat*. The unit "bloops" when you plug it in and the charged light went from red to orange in time, but that's as far as it went. No sound after a while when plugging it in (I kept changing chargers to see if they make a difference). I had just found a 24V 200mA charger for a Shark vacuum. I plugged it in a it made the "bloop" sound. I hope that voltage is not too high. Thanks again.