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Bottlehead S.E.X. Amplifier - Get Your Tubes Glowing
By James Grahame
Tube amplifiers are incredibly sexy, but they tend to appeal to an older crowd. Well, I think Bottlehead Corp. has finally figured out how to grab the attention of youngsters far and wide. They obviously blew all their money on the photographer, leaving nothing but a meager shoe budget for their model. Shucks.
You're looking at the Bottlehead's Single Ended eXperimenter's kit (errm, at least you're supposed to be). The original S.E.X. amplifier was created one Sunday afternoon in 1994 by three members of a Puget Sound area vacuum tube audio club. They were stunned that their incredibly simple single-ended design produced great sound. They founded Bottlehead Corp. to manufacture the kit, and the company grew to offer a full line of tube amps and pre-amps.
The S.E.X. kit was revamped in 2004 and sells for $369 plus shipping. It puts out 2W per channel and makes a wonderful headphone amplifier. Of course, it will also drive high-efficiency speakers with a sensitivity of 95 dB or higher. I know it sounds like blasphemy, but one of these little amps would be a perfect partner to warm up an iPod. And don't forget that this kit is designed for experimentation. It ships with a pair of 6DN7 dual triode tubes, but there's nothing stopping you from swapping in a pair of 6EM7's or rewiring it as a 4W parallel single-ended monoblock amplifier.
Not sure if you have the skill to build one of these kits? The Bottlehead gang explains that the S.E.X. is "intended for the novice builder with no previous experience soldering or assembling kits. Detailed instructions are given about the craft of soldering, and the kit can be assembled with no knowledge of electronics beyond the basic ability to tell a resistor from a capacitor. The assembly instructions themselves are considered the most approachable and comprehensive in the industry. They are very detailed, with step by step written instructions accompanied by a detailed drawing of parts placement and/or a color photo of the underside of the finished kit."
So get to it - practice makes perfect, after all -- the skills you learn while building and modding this kit will serve you well if you decide to move up to one of Bottlehead's 300B or 2A3-based monoblock kits in the future.
Bottlehead Single Ended eXperimenter's Kit
