Dynaco ST-70 MAXThis is a rebuild and customization service for your Dynaco ST-70 power amp. (The photo is a stock photo from the Tubes4HiFi web site. Yours should look similar when completed except it will not have a rectifier tube.) We've been rebuilding and modifying tubed amps for almost 10 years, and have evolved our work on the ST-70 over that time. You provide the ST-70 with good transformers, well-packed (we’ll use your packaging to send it back to you). We don’t need the 5AR4/GZ34 or 7199 tubes. Return shipping to you is additional. We: - Install the Tubes4Hifi 6SN7 driver board with Russian paper-in-oil coupling capacitors. We supply three tested 6SN7s. Bypass filter capacitors on driver board with film capacitors. - Rebuild the power supply using UF4007 diodes, much more filtering than original, and semi-dual power supplies. Final filter capacitors are bypassed with film capacitors. - Install switches to allow Triode or original Ultralinear operation (Triode operation sounds vastly better). - Install a low-noise cooling fan on the power transformer. We can: - Furnish new EL34s if you’d like (extra cost). - Replace input and or output connectors (extra cost). - Discuss other options. You can contact us through Audio Asylum or directly at lee@electronaddict.com with questions or to make arrangements.
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