A Tube Stereo Amp Built In The Style Of Classic McIntosh

I’m a fan of old McIntosh HiFi equipment, especially their tube power amplifiers. They have a very unique design both electronically and also physically. For those unfamiliar, here is one of their flagship amps of the 1960s, an MC275, which outputs 75 Watts per channel……and weighs close to 70 pounds!

McIntosh MC275 Power Amp – A tube stereo classic
TLDR: 17 Watt per channel (i.e. MC217) built as a “mini”
MC275

I’ve had, for several years, a partial collection of parts (transformers, tubes, etc) to build a copy of a much more modest stereo amp called the Dynaco ST35. Dynaco was a lower cost competitor of McIntosh in those days but was still considered a good quality path to HiFi for many budget conscious college students (like me). As you can see below, the Dynaco unit, true to its budget genealogy, is a pretty plain box.

Dynaco ST35 tube stereo power amplifier output 17.5 Watts per channel

I wanted to make use of my tube amp parts, but in a way that “looked cooler”. I decided to build a “Mini-me” of a McIntosh MC275 with the innards of a Dynaco ST35. The key to this would be the metal work. Two tricky aspects in particular were the McIntosh slanted front panel and the transformer covers.

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