Easy Headphone Amplification

home_listening · Jun 4, 2013

Hi,

I'm putting together a headphone amplifier section for a console at the moment, just for powering a single pair for late night mixing. With all the chip amps floating about and other great all-in-one-IC solutions, I was wondering if there was anything similar for a headphone amplifier that I'm missing. Some sort of gain control would be great, but I guess its not too much of a problem to attenuate before it enters. I don't need anything capable of driving anything too low in terms of the load, just a standard pair of headphones.

Any help greatly appreciated!

..::edit::..

worth mentioning I want something powered off +/-18V (if possible).

Rochey · Jun 4, 2013

have a look at TPA6120A2.

/R

00940 · Jun 4, 2013

tpa6120a is very picky about pcb layout and capacitive loads. It won't work with +/- 18v either (max 33v). Sounds great though.

For an all-in-one solution, there are the opa551/opa552. Not great but plenty of current and +/-18v is no problem. It probably need an output inductor or resistor, as the tpa6120a.

At those voltages, if you've got room on the pcb, a "classical" solution would be an opa2604 with a simple bjt buffer (a pair of b139/140 biased by diodes). Or maybe a pair of ne5532, using two opamps in parallel.

JohnRoberts · Jun 10, 2013

Step one is to figure out what kind of head phones impedance you want to support.

There are a number of decent canned solutions for the actual HP amp.

One very common newbie console designer mistake relates to the headphone output ground return path back to the PS common. An inexperienced master section PCB layout with a front panel headphone jack and heavy ground audio currents commingling with other low current ground audio can corrupt and crosstalk into otherwise clean master section audio paths.

The physical layout matters, give it a clean robust ground return path of its own.

JR