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![](/images/621.jpg) | Dynaco ST70 Stereo Tube Amplifier | Vintage Dynakit by Dynaco, ST-70 tube power amplifier, with 4 Mullard reissue EL34 output tubes (Russian). 35 watts per channel. I replaced the electrolytics, selium rectifier and put an new upgrade board that has a pair of Amprex 6GH8 tubes. The old boards on ST70s are frequently leaky between traces. The new board has 1% resistors. I set the bias at 1.41 volts (I prefer to run them a little low to give greater tube life). The chassis chrome is pitted in places but overall is good shape. I have listened to this amp for over 20 hours & love its sound. It has that clean warm tube sound.
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