TPA6102 and 600 Ohm headphones, is 2x9V batteries enough?

[DainB]

Greetings, first post here and mostly noob in analog electronics, so please be gentle..
So I found in an thrift store Philips N6330 (sibling of AKG K240), which are 600 Ohm headphones and need something to drive them and there's not as many options as I expected. Not ready to invest more than pocket change yet so found this TPA6120 board on aliexpress for ~7EUR which looks like it should do the trick for now, but I don't have a suitable +- 12V transformer readily available. I suspect this board has something like pair of LM7809s on it as it wants +-12V AC, but don't have any means to verify it.

So the question is, if I bypass rectifiers and connect two 9V batteries, would that be enough to drive 600 Ohm headphones, at least to see if I like their sound and buy something better?

The other option is get +12V and -12V DC from old ATX power supply, would that be a better choice?

 

[Galu]

Here is a helpful (edited) description:

"TPA6120A is HIFI stereo headphone amplifier. It can provide 800mW power to 600Ω with a ±12V voltage. The operating voltage range is ±5~±15V."

According to the description, the board can run off +/-9 V, but I suspect batteries would not last very long.

 

[rayma]

Hook the 9V batteries up and listen. Quickly.
The ATX supply would be noisy.

 

[Galu]

P.S. I see that other specs I've found say 80 mW (not 800 mW) into 600 Ω at ±12V.

The board, of course, can work with both AC and DC supplies.

 

[cowanaudio]

The AKG K240 are 98dB/mW. With 80mW of drive they will deliver 117dB to your ears, a bit less with ±9V supplies on the amp.

Only you can decide if >110dB at your ears is enough.

 

[DainB]

Only you can decide if >110dB at your ears is enough.

Ah, thanks, that's the calculation I needed to see. Thanks a lot!

 

[DainB]

Hook the 9V batteries up and listen. Quickly.
The ATX supply would be noisy.

Even if it is passed through LM7809 or whatever is there on that board?