I built this little amp about 6 months ago and it's seen about 25 hours of use. You could think of the amp as a JE Labs "Simple 45" except it uses the 1626 output tube (the schematics are virtually identical except for output tubes and naturally different operating points). The tubes include a 5U4GB rectifier, a pair of 1940's Hytron 1626 power tubes and an RCA JAN Black Plate (graphite coated envelope) 12SL7 driver tube (all tubes were new with the amp and have about 25 hours on them max). I've really enjoyed this amp in my Den and used it to drive some custom made 94 DB single driver speakers with plenty of volume and dynamics for my listening level. The tube puts out about .75 watts per channel so more efficient speakers will be needed in a larger room. However, I let one of my friends with a pair of Lowther Alerion speakers at around 94 db efficiency listen to it in his larger room and he really liked it. But he already has two of my hand built amps and couldn't really justify buying another one (he has several other tube amps as well) so this one is available to the public at large. The amp has an overbuilt power supply and is really quiet. I used a seperate filament transformer with center tap to help with hum balance and avoid any coupling noises between windings in the power transformer which I think helped. Some other details about the amp: -- NOS USA Made Pyramid Paper in Oil Coupling Capacitors -- Teflon Jacketed Silver Clad copper for all signal carrying wires. -- Made in USA new Edcor output transformers -- Super short signal path, with an attempt to use only the leads on most resistors to minimize the number of solder joints. -- Lead free Kester 3% silver solder used exclusively -- Vintage Power transformer that I picked up on Ebay last Summer (spray painted it a hammertone black to match the plinth). -- A hybrid star ground that uses a short silver clad copper bus bar that is reputed to be quieter than a straight star ground (high currents are kept from commingling with sensative signal circuits).
The amp is point to point wired, although I did build the power supply on a perf-board to conserve space and to better group the power supply grounding node. I've owned at least 15 different tube amp designs (not just tube amps but actual designs) and can say this little fella is as good as any I've owned provided it's used within it's power limits. Vocals are it's forte with the nod going to female vocals. Regina Spektor for example sounds like she's sitting in the room playing her piano. But, I'm building a 2A3 amp soon and have several other of my tube amps lying around so off this one goes to fund the next project. I called the amp an 7/10 due to the DIY nature of it and the fact that the wood I used for the base had some blemishes. It has a really interesting pattern that I couldn't pass up, but had been banged around a bit prior to finding a new life as a tube amp and try as I might, I couldn't sand out all the flaws. It's not something you would notice beyond a few feet and is still very attractive... but it's not perfect (I'm my own worst critic mind you). Shipping weight will be around 24 lbs and I'll split Paypal fees.
| 
