Hello everybody,
I made a small board which contains a headphone amp, using a dual opamp (OPA2134 in DIL8) as a gain stage, and then four unity gain opamps into 1.6ohm mixing resistors in parallel, per channel.
I used a quad opamp per channel, it's a OPA4134 in an SMT package. The OPA2134 is lukewarm, but the smaller quad opamps are pretty hot, I'd estimate about 55 degrees or so.
From a reliability standpoint, I'd rather have them a bit cooler, or is this higher temperature no problem? Would lower rails (currently +/-15volts) help? And a higher value for the mixing resistors? This amp is meant to drive 32ohms headphones, so I could go upto 8 or so ohms mixing resistors?
I made a small board which contains a headphone amp, using a dual opamp (OPA2134 in DIL8) as a gain stage, and then four unity gain opamps into 1.6ohm mixing resistors in parallel, per channel.
I used a quad opamp per channel, it's a OPA4134 in an SMT package. The OPA2134 is lukewarm, but the smaller quad opamps are pretty hot, I'd estimate about 55 degrees or so.
From a reliability standpoint, I'd rather have them a bit cooler, or is this higher temperature no problem? Would lower rails (currently +/-15volts) help? And a higher value for the mixing resistors? This amp is meant to drive 32ohms headphones, so I could go upto 8 or so ohms mixing resistors?