Cafe Walter HA-1 Bass Headphone Practice Amp

This is the best headphone amp for bass guitar.  They are really popular and are not currently in production.  It's best features is that it's simple and well-built.  It's built like a tank, and is in perfect condition.  The clear stick-on bottom foot came off so I put some black Sugru on for a new foot.  But it can accommodate other bottom feet too.

Here's the description from the manufacturer's website:

The HA-1A Headphone Practice Amplifier is a simple but high fidelity instrument amplifier, designed to allow you to practice your electric instrument through headphones.  Unlike most music equipment, the HA-1A is not designed to make you sound good. Instead, it is designed to tell you the truth about how you sound. If your fingers make squeaky noises on the strings when you move, if your E string is twice as loud as your D, if your intonation is lousy - the HA-1A will tell you. And if you sound great, it'll tell you that, too. There are no tone controls, effects loop, enhance knobs, or subharmonic thingamajigs: the HA-1A tells you what you do sound like, not what you wish you sounded like. Your skills will improve because listening to the instrument in this way points out every little defect in your playing (warning - this may be painful). And your relationships will improve because your neighbors and family won't have to listen to those same defects, over and over and over and over again.