FOR SALE OR TRADE: Very, very nice pair of Heathkit W5 monoblocks professionally modified by two highly experienced tube amp pros to extract the musicality of the special breed of 6L6: the 6AR6 tube. Premium parts used. After I heard the first tech convert to 6AR6, I became so enchanted with the sound, I asked Jeff Larson of Abraxas Audio to do some more magic to take the sound a step further--and boy--did he.
Background: If you like the GL6 tube sound, which I do, but feel it puts out a bit too much upper midrange glare ('shouty'), these modified amps take care of that issue so nicely with the 6AR6 tube. The shout is transformed to a warm-of-neutral seductive and transparent midrange tone. Pentode amps sometimes are too much of a good thing on horn speakers--like from Klipsch--or ribbon tweeters. The 6AR6 tube was invented by Tung-Sol and has special characteristics. It was a premium tube, designed for long life and efficient electron transfer with new plate materials and coating technology.
The Ultralinear output transformers of the Heath WM monoblocks with their Peerless 16458--arguably among the best output transformers ever made (flat: 1-80K Hz). Male and female voices portrayed with SET-like realism,but also extended highs and tight lows. The damping factor for the Heaths is 50, which is quite excellent for a tube amp. Furthermore, the S/N is ~100 dB. On my Cornwalls and Hammer S-12 98 dB speakers, these blocks are virtually dead quiet, unless you listen as if they are a headphone, with ear right up to drivers--and even then--virtually noise free.
It puts out 20 solid watts per channel and has fixed-bias
(the only true way to go) with easy to use bias-level and bias balance controls on each block to ensure perfect push-pull tube matching. Except for the world-class power, choke, case and (esp) the ultralinear OPTs, all the parts underneath are new and very high audiophile quality.
I will post more pictures of the outstanding workmanship and high quality parts. If you search Audio Asylum, you will find a few acknowledged tube audiophiles expressing their surprise at how good the 6AR6 sounds.
These monoblocks will come with two strong match quads of the old-style TS 6AR6 tubes. Although you do not require matched tubes due to the military grade balance and bias pots adjusters, a matched quad is always better to start with, ensuring all tubes will age similarly and in balance. The drivers and signal tubes have been optimized to take 6CG7 and EF86 (instead of a pair of 12AU7, which originally was a horrible choice by Heath, as they 'veiled' the sound and compressed the sound stange).
The blocks should give a lifetime of service, reliably, including top-shelf tube rolling options. Just look as the expert soldering and elegantly laid out circuitry. More pictures to come.
Jeff Larson, formerly of Abraxas Audio, now retired (sadly; sniff), is the one who did a transformation on this amp--after another pro took it to level 1, Jeff of Abraxas Audio took it a quantum leap ahead in sound. I simply could not believe the transformation in sound through my modified Klipsch Cornwall speakers with ALK X-over network, after I got these amps back. Talk about system synergy! The Cornwall shout is gone!
Given the age, and the fact that most of these that are available are in sad condition, I am rating at 7/10 'vintage-audio standards'. One amp is in outstanding condition (9/10 given the age) and another is quite respectable (6-7/10), but with more wear on chassis. Comes with the two original tube cages. Heathkit put the buck into the iron!!
These are very special amps, I assure you. DEAD, DEAD quiet on my 97 dB speakers--and I will be very if not dead quiet even on 103 dB sensitive speakers!!
If you are local to Philly, you can even try them out, I accept returns if not delighted.
I only reply to AA or Agon members who have feedback elsewhere and also supply me with their user name on Agon and email address. My feedback as this same seller is spotless on Agon, here, Ebay and HeadFi. Thanks.