Member Reviews: Bottlehead Crack OTL

This was an amazing and fun purchase for me. It was fun to build and it makes my HD600s sound great. Very simple design that does everything I need it to for my headphones. I don't believe I'll ever purchase another amplifier unless I fall in love with a low impedance headphone that needs amplification.

The Crack kit is easy to build and sounds incredible. Don't be scared of the DIY approach even if you're a beginner - it's fun and SO worth it!   Mine had some induced noise at first so I replaced the braided input cable with some shielded coaxial cable and it fixed it perfectly. I see that and potentially damaged/faulty tubes as being about the only real possible issue with this amp.   Once built (takes a day or 2 depending on how long you spend in one sitting) the final result is an amp with incredible staging and layering for the price combined with beautifully smooth and cohesive sound presentation. There's plenty of detail, but it's all cohesive and realistic - it...

This is a review of the Crack amp driving Sennheiser HD800s. I haven't had the chance desire to audition it with any other cans. The price is for the amp ($213) and the Speedball upgrade ($110).   I've had the combo for about two years, and have several hundred hours on it. The Crack is an OTL headphone amp kit, designed for high-impedance phones. Assembly is easy, the directions are excellent, and support on the Bottlehead forum from Dan Schmalle and his very active, knowledgeable customer base is superb. After living with it for a while, I added the Speedball power supply upgrade; it may have made a slight improvement - hard to say without being able to A-B it. I also...