AMB Beta22 B22 headphone amp with Sigma22 PSU
Up for sale is my 2 channel Beta22 -- a fully discrete, high current, class A headphone amplifier that’s considered, according to Mike at Headfonia, to be "the best of the best in solid state headphone amplification". Why?
For one thing, its power reserve (0.75W into 300 ohm; 5.6W into 32 ohm; 18W into 8 ohm). With this power output, the Beta22 is capable of driving tough Orthodynamics (like HiFiMan HE-6) but also the hard-to-drive AKG K1000 to very high levels. Moreover, though likely it is an “overkill” for any in ear monitors, the fact that its output impedance is < 0.01 ohms means that it will do a great job there.
A note about 3 channel design: As you might know, there is a 3 channel design Beta22. Why a 2 channel one when you can get a 3 channel? Well, according to people at Hydrogen Audio, the B22 already has a dual split power supply and a real ground. So, adding the 3rd channel does not add anything. Indeed, the conclusion is that a 2 channel amp (if well designed) will always outperform a 3 channel one. Think twice!
A note about DIY: Beta22 is an open-source, DIY amplifier. Yet, unless you are very experienced, don’t think starting a DIY project with it (there’s a thread called “The journal of the longest β22 build ever” at Head-fi.org). And getting it from a professional builder is going to be even more expensive (according to a quotation I recently got, before labor charges, parts already cost $760+ so it can go up to $1200 easily, depending on other costs), not to mention the delivery lead time (it is going to take 4 to 6 weeks to build one, even for a professional builder).
Specs:
- Pactac case with vents CNCed on the top
- Input: RCA input on the back, and an additional 1/8 inch input on the front
- Output: an 1/4 inch headphone jack plus an additional 1/8 one for convenience
- All wires are braided (where possible), and all the wiring in the audio path is silver plated copper from Navships
- Two-chassis design, with the PSU's (which is the recommended Sigma 22) toroid housed in a separate case to keep noise out. Right now it is wired to work with 110v. If you want 220v, can do it at extra cost (but I will need like two weeks to get that done)
- Gain is set to 5x
Condition: Used - Good on Amazon condition scale. Not comparable to commercial offerings though cause Beta22, like other DIY amps, are built by hand. And the HD800 and the DACport in the photos are not included!
Will split shipping fee with CONUS buyer. International buyer: I might consider shipping it overseas. Please check with me for details and additional shipping fee.
Accepts PayPal personal or buyer adds 3%. Also accepts Amazon payment, which is free for both buyer and seller.
Thanks for looking. I have done a lot of trade at flea bay with 20+ feedback. Feel free to ask me for reference!
