Maple Tree Audio Design (MAD) Ear+ Purist HD150 tube limited ed. headphone amp (240VAC, AUSTRALIA)
Will Ship To: Anywhere
Hi guys, I am selling my beloved Maple Tree Audio HD150 'tube roller special'. Total of 20 were made for the anniversary of the MAD's 150 production. The full PDF docs can be found here complete with parts list and schematics: http://hollowstate.netfirms.com/HD150manual.pdf
According to Dr. Peppard "It is a special signature limited edition of one of the best headphone amplifiers available at any price." High lights of this unit is the use of 2 giant Sloen coupling capacitor and 2 Black Gate Coupling capacitors. I am pretty sure you can't get Black Gates anymore apart from paying a premium from ebay (I just sold a few of them, for more than $20 a pop).
The utilization of transformer output also enables it to drive low impedance cans like the AKG 701 and Grado RS1 with ease. In fact it was considered one of the best amps to pair with AKG K701, which is what I use.
The amp itself is in full working order, and cosmetically a few paint chips and scratches due to age, but nothing too serious. There is a pic shows the paint loss.
As of the tubes, there is a JJ ECC99, Russian 6N6P, RCA 12BH7A for the rear; and also a Mullard 12AX7 reissue (russian) and GE 12AX7 for the front. All of them in great shape as the amp was not used a lot.
Reason of sale: no time to sit around listing to cans anymore because baby just arrived.
Edited by pkjames - 10/15/12 at 5:58pm