I recently bought the Sugarmaple (Mapletree) Sidewinder. This was designed and built by Dr. Al Freundorfer, an Electrical Engineering prof at Queen's University in Kingston, Ontario, Canada, and associate of Dr. Lloyd Peppard.
What I purchased is the second of two prototypes for the Sidewinder. It's pretty nicely designed and built. While the finishing on it is less polished than what you'd find on factory-made products, it feels hand-made. Which is exactly what this is, and in part what I like about it.
It has a low and high gain output. it was supplied with two Amperex E88CC output tubes and an electro-harmonix 12AX7 driver tube. Front panel has a power switch, volume knob, and two output jacks.
It's hooked up to an Anthem Pre1P phono pre, and, as my source, a Rega P7 turntable with a Dynavector 20x2 cartridge. Headphones are Grado HP-1000 drivers (@ 40 Ohms) with custom cups.
Upon first listen, my initial impressions were mixed, but after switching the Electro-harmonix 12ax7 driver tube for an RCA Command 5751, the music really came alive. The clarity and overall presentation improved dramatically. It livened up a lot and became what I hoped it would be. It sounds amazing with my Grados. I have no experience with other Mapletree headphone amps, but I'd be curious to compare. I prefer the high gain output for a bit more punch but the low gain is also nice.
Really enjoying the Sidewinder.
See more pics below.
Edited by davstev - 3/30/15 at 6:15am