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Amplifier running off a power bank?

abdo123

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I want to do some ground plane measurements of some speakers I have, I live on top of a hypermarket so the parking lot Sunday morning would be perfect for that.

However delivering power to even a handheld class D amplifier seems like mission impossible without buying an external generator. I was wondering if there are amplifiers out there (to deliver 1 to 5 W of power only) that i can use with a mobile phone power bank?

There are really no requirements other than a decently behaving frequency response vs impedance. In other words it just has to work and not pollute the measurements much.
 
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abdo123

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You can get a Raspberry Pi amp HAT or an add-on for Arduino MKR ZERO. These ones output 7 W @ 1 kHz into 4 ohms.

This is fantastic! Exactly what i need! I wish somewhere in the specifications there were a frequency response curve at different impedances. you know just for ease of mind.

Thank you for sharing!
 

DVDdoug

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How about a car stereo amplifier or an amp that can run from 12V?

With a 5V power supply and a bridge amplifier you can get a theoretical maximum of 10V peak-to-peak = about 3.5V RMS.

Power can be calculated as Voltage squared / Resistance so that's about 1.5W into 8 Ohms and about 3W into 4 Ohms.

(High power car stereo amplifiers have a built-in voltage-boosting DC-DC converter.)
 
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