I am currently using the Cafe Walter HA-1A. I tried two other headphone amps: a Vox Bass amp and a Concept3 amp. The Vox amp was fair sounding, but somewhat noisy, and it broke after only a month. The Concept3 was extremely noisy and I could only tolerate short practice sessions with it due to ear fatigue.
The HA-A1 unit just looked impressive right out of the box. I has a no nonsense box design, simple graphics and basic control knobs. When I first plugged my Fender Jazz bass into the HA-A1 using Sony MDR V-6 headphones, I thought there was something wrong there was absolutely no hum or hiss, zero! When I started playing, I was completely blown away by the clarity of the sound, and am really amazed at how much better the experience of practicing with headphones is.
Yes, it's more expensive that other headphone amps, but sometimes the extra bucks are worth it. If you intend to practice a lot, I would definitely check it out. You have to order it through Bass Northwest and it runs about $169 plus shipping.
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