Price reduced to $1000.

Beautiful Dynaco amplifier. This is the rare Series 2 version of the classic Stereo 70. It has much bigger power transformers, solid state rectification, and various other circuitry upgrades to the design. This model was released in the early 1990s, and has the advantage of being in like-new condition, compared to many older kit models of the original Dynaco, produced in the 1950s-70s. It has a beautiful chrome chassis (even underneath!), with a chrome plate covering the circuit board (a weak spot in the original, the phenolic board was exposed). Another improvement to the design is the tube bias controls in the front, which make for much simpler bias matching via red LED display. I have never had to adjust bias on this amp after setting it initially. You simply insert a small screwdriver into the front slots and turn the adjuster until the red lights are balanced (I’ve always set the bias slightly below a positive reading, to encourage longer tube life and less noise). 

I am including ALL the tubes I have with the amp (see photos), which means the premium set of matched tubes currently installed, as well as numerous backups. You will enjoy tube rolling with this amp combo (although I admit that the current tube complement is terrific). The driver tubes of the original ST70 were 7199, which are no longer produced. Dynaco changed the drivers to 6GH8-A tubes for the Series II, which at the time were still in production, and are still easy to find NOS, and inexpensive. Power tubes are EL-34, like the original.

Current tubes are: matched Quad of JJ KT-77 power tubes (slightly more powerful but drop-in equivalent for EL-34 tubes). Driver tubes are Amperex 6GH8-A new old stock matched pair from France. I also have the original Dynaco branded driver tubes, which were Chinese made. They are perfectly fine, but the Amperex tubes make a huge sonic improvement.

Spare tubes include a quad of Svetlana new issue EL34 tubes (unused, they were installed by a tech who thought I should have new tubes - I just swapped them for the JJ’s), and three unbranded vintage EL34 tubes. There are eleven vintage driver tubes included: a variety of RCA, GE, Raytheon, Magnavox, National Electric, etc., and the original Dynaco labeled tubes. All of them work, but are untested in terms of voltage matching, etc. I do not have the equipment for this.

The Series 2 amp was fitted with heavy duty speaker binding posts, including posts for 4, 8 and 16 ohm speaker loads. This is another detail that you will not have to upgrade, compared to the original kit model.

I will ship this very heavy amp (a little more than 25 lbs.), but only within the US or Canada. Of course, if anyone local wishes to purchase the amp, a pickup would be welcome and encouraged. I have no idea yet how much shipping would be, but if my Buy-it-now price is met, I will ship the amp for free. I will pack it very carefully, with double boxes and foam in between the boxes. The amp was shipped to me originally and I am confident that it will be safely packed and shipped again. 

I love this amplifier, but I simply have too many tube amps, and haven’t been using it regularly for a couple of years now. I’d like to see someone else enjoy it than let it sit on the shelf like a trophy, even though it is beautiful to look at.

Thanks for looking, and feel free to contact me with any questions.

Please note: I do not have a cage for this amp, it was not supplied when I first got it. 

Specifications

Description: Rated power: 35Wpc (15.44dBW/8 ohms), 20-20kHz, at less than 0.25% THD. IM distortion: less than 1% up to 30W. Frequency response: 20-20kHz ±0.5dB at rated power. Input sensitivity: 1.3V.

Dimensions: 13" W by 9.5" D by 7" H. Weight: 35 lbs.

Original Price: $995 with standard black finish, $1095 with chrome chassis (1992); no longer available (2004). 

Manufacturer: Panor Corp., 125 Cabot Court, Hauppage, NY 11788. (Note: Dynaco is now owned by Hafler)