Well, I'll try not to do too many of these, but this post is remotely related to radio. 🙂
Anyway, last week or so I was reading up on the CMoy Pocket Headphone Amplifier. I came across this a few years back, but I think at the time I thought it was a bit too difficult – not sure why. Well, last week I assembled and tested it, and last night I finally placed it in an enclosure – although not an ideal one I will say (replacing the battery will involve removing four screws.
So right now I'm sitting here listening via it. I'm at work though so only have some basic low impedance Sennheiser ear bud headphones. As a result, I've got my source (iPhone 3G) one step off mute and it's a nice and strong signal – actually, if I mute the iPhone I can still clearly listen.
I also tried the amp at home last night with my Sennheiser HD-215s and it sounded fantastic – it really does prefer more impedance. It's not perfect though, and so I plan to build another with a few of the options – such as a potentiometer, an output coupling capacitor and larger capacitors.
But overall, the current one is performing great and has really brought to life the sound – nice and dynamic, no longer flat… Noice!