Selling Modified Dynaco Stereo 70 amplifier

[Original Burnedfingers]

Hi,

I am wanting to sell a modified Dynaco stereo 70 amplifier. This amplifier has had the nickle stripped off the chassis and has been chrome plated. The amplifier has a Mapletree Driver board, triode electronics power supply board, individual bias adjustment pots, triode electronics power transformer, Technitrol Z326 output transformers. The amplifier has a new Sovtek 5Ar4 rectifier, EI EL34's, JAN 5693 and Russian 6H9C(6sl7's). It works great and I have over $600 invested in this beautiful amplifier without even figuring the cost of tubes. Amplifier has a cage also.

Feel free to email questions and such. Will consider serious offers.

After looking at the uploaded pictures it looks like there is rust on the transformers. Its a lighting issue there is no rust.

[cowboy99]

.....the question arises...serial # ?

Is this a vintage ST-70 that has been impressively modified or is this a Panor/Dynaco ST-70 clone with mods/options.

The serial number and its location would be the most definitive answer.
Thanks
Charles

[Original Burnedfingers]

The amplifier originally had a GSI driver board in it. I see no serial numbers on it nor do I find any serial numbers on the other 4 Dynaco stereo 70 amps I have.

I modified the amplifier myself by installing the larger power transformer, driver board, power supply board, and adjustable bias circuit.

Reason for selling is as follows:

I will be getting a bypass soon. Insurance will be leaving me paying around 5k. Toys are getting sold.
Will be selling 4 other amplifiers.

[Original Burnedfingers]

Additional pictures

[cowboy99]

That was the correct answer,
..... Sorry for the trick question, so many trying to claim new clones are vintage......the clones actually have serial numbers now....Nice unit...are you selling any of the others?
Let me think on it
Charles

[Original Burnedfingers]

Yes,

I have 2 more with the Mapletree driver board that I cloned. One is older and has the cloth leads on the output transformers. This one has a driver board that I made that has turret terminals. It also has a switch that allows either
6BG6GA's or EL34's it will also run some Russian output tubes. It has a add on power supply board also.

The other one has a Mapletree clone board and the circuit is mounted on an aluminum board. It has a add on power supply board also. It has a Japanese output transformers. It sounds really nice.

Both amps have individual adjustable bias for all output tubes.

I have one Dynaco stereo 70 with a SDS driver board. The board uses a pair of 6AU6's and a 12Au7 or 12BH7. This one's chassis looks bad but it runs out real nice.

I will upload pictures of the two with clone Mapletree driver boards and pictures of the SDS unit to follow as soon as I get a picture.

I have two unused stuffed SDS boards like that one that are ready for use.

[Original Burnedfingers]

Pictures of Dynaco with SDS driver board.

This one is kinda rusty. Has cloth transformer leads on output transformers and power transformer.

[Original Burnedfingers]

OK,
I call this "spare parts amp" I built it from individual pieces as a project.
Found one more amp. This is an amp that I put together using a HP power transformer, original cloth covered lead output transformers, triode electronics power supply board.

I added a 6DW4 damper tube into the power supply to bring on a slow power supply start. I added individual bias adjustment pots for all the output tubes. I added different speaker connections and input jacks.

It uses an external transformer to supply the bias voltage to the bias circuit on the power supply board.

It has 6BG6G output tubes, a 5U4 rectifier tube, 6DW4 damper tube. It has 6SJ7's and 6SL7's in the driver board.

Like to get $425 OBO plus shipping on this one. Will take offers. Chassis has some discoloration not bad shape.

[Original Burnedfingers]

I'll go $550.00 shipped for the Mapletree amplifier in post 1. Pictures can be seen in post 1 and post 4. That price will include shipping in the continental U.S. Alaska and Hawaii extra.

[EvilYoda]

Not for me, but I sent this thread along to a friend that I hope will be very interested. Problem is...he has a wedding coming up so most of his money and attention is focused toward that.