Arthur Loesch 845 211 SET Mono Amplifier Kit

Arthur Loesch 845 / 211 SET Mono Amplifier Kit

From the estate of the late Dr. Arthur Loesch, comes these components that form the nucleus of a pair of Loesch-designed 845/211 SET mono power amps.

These were removed from Dr. Loesch's personal amplifiers. I was Dr. Loesch's long-time friend and business partner and after he passed away, was asked to sell off his collection of audio-related parts and gear.

In testing his original, hand-made 845/211 amplifiers, a number of the Axon capacitors in the power supply began to fail. Although they were rated for 1200VDC, these early examples were fabricated with insulating film that was not thick enough to survive the 950-1100 volts that these were designed run at. Apparently, these were not the only Axon caps to fail, since later production from Axon was substantially beefed up.

While it was my original intent to completely rebuild the original amps with more substantial parts, after several years, it became clear that I did not have the time for this project. So, I deconstructed the amps and put together a DIY kit, including vintage and modern power supply caps with ratings of 1500VDC and 1300VDC.

The complete kit includes:

(2) George di Stefano, Magnetic SA, 845/211 Custom-made Output Transformers

(2) Peter W. Dahl Custom-made Power Transformers with matching metal covers

    Primary: 117V @ 60Hz
    Secondaries:  (1) 400-0-400 @ 350mA
                         (1) 425-0-425 @ 350mA
                         (4) 5V @ 3A

(2) Sangamo 8uF @ 1500V Oil Capacitors with (8) new hold down brackets

(2) Wima MKP5 15uF @ 1300V Polypropylene film capacitors with hold down brackets

(2) Wima MKP5 40uF @ 1300V Polypropylene film capacitors with hold down brackets

(2) Wima MKP5 55uF @ 1300V Polypropylene film capacitors with hold down brackets

(2) Johnson 845 / 211 Tube Sockets with stand-offs for mounting under the top plates

Copies of Arthur Loesch's schematics and notes

In the late 1990s, Dr. Loesch met George di Stefano at the Consumer Electronics Show in Las Vegas and commissioned him to wind three pairs of output transformers to his specifications. Two pairs were sold to audio colleagues; this was Dr, Loesch's personal pair.

The Peter Dahl power transformers, also pulled from the original amps, offer a choice of high voltage secondaries, as well as four pairs of 5V @ 3A secondaries for the four rectifiers that the design calls for. Dr, Loesch felt that it was safer to split the approximately 1,000V B+ between four rectifier tubes, hence the need for four 5V lines. Because they are used pulls, the leads were shortened to reach the four sockets. Depending on your layout, extensions may be required.

The Sangamo 8uF oil capacitors are NOS and the correct value to use with 5V4 rectifiers. They were repainted to match the transformers. The Wima caps are all new, unused, but two were installed in one of the original amps before the upgrade project was abandoned. The blemishes on two of them were made In the course of removing them, but have not effect on their function and are hidden by the mounting clamps.

The pair of Johnson 211/845 sockets are clean, vintage examples and include standoffs for under top plate mounting.

For your reference, the last photos show the original amps, but only the parts listed above are included in this sale.

The net weight of this collection is 72 lbs. Shipping weight, in four cartons, is about 92 lbs.

Shipping cost estimates, via FedEx Ground, subject to your actual location are:

    $115 to the East Coast
    $160 to the Midwest
    $175 to the South
    $245 to the West Coast

Pick-up from downtown Troy, NY, is welcome. Depending on your location, I may also be able to meet you up to 120 miles from Troy.

Sets of rectifiers, drivers, and power tubes may be available, but are not included. Inquiries and any other questions are welcome.