I mentioned this little balanced speaker amp in the "speaker amp for headphones" thread but this amp is such a great high output headphone amp I thought it deserved its own thread.
I picked up an $18 Stellar Labs desktop amp today from MCM Electronics. It's a Tripath TA2024 Class T based desktop amp rated at 15 watts into 4 ohms for both channels. I'm powering it with a 3 amp rated 12 volt power supply ($15 from MCM Electronics) but it can run off 8 internal AA batteries for portable operation too. The TA2024 chip amp has unbalanced (single-ended 1/8" TRS jack) input but uses true push-pull amplification with balanced output (see schematic below--note the unbalanced, common ground input is a chip level design).
It easily powers my hard-to-drive modified Fostex T50RP cans. Max volume for me comes at 10 to 11 o'clock on the Stellar Labs amp so it's not being pushed at high volume and it's dead freakin' silent at max volume. I A/B'd it against my Schiit Mjolnir using my HE-500 and T50RP cans and it stands up pretty well--no schiit, it really does. The TA2024 has a little more bass and the highs are a little less bright than the Mjolnir but both of these are really a slight improvement for the HE-500 if you ask me. Seriously, this little $18 to $35 amp punches way, way above its weight. Listen to it with an open mind (or a blind A/B test) and you'll freak out. I know it's crazy cheap but if you're on a severe budget and want to try balanced headphone operation or you just need a another amp give it a try, you won't be sorry.
Note you cannot use a headphone adapter with common ground such as an adapter with a female TRS socket. The speaker-to-headphone adapter must have four wires and separate L- and R- wires.
Edited by robrob - 11/25/13 at 5:46am