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Do It Yourself (DIY) paradise for tube and SET project builders.

This is a bunch of B.S. nonsense....

The Marantz 9 runs the tubes conservatively at 55 ma with 440V on the plates. The output tubes last a long time on it. I have been running two quads of NOS Mullards and the getter flashes look nice and shiny after 3 years of use, averaging a few hours a day.

The amplifier also runs very cool. After 3 hours the transformers are barely warm to the touch. All components run as conservatively as possible.

As for instability, it is rock stable needing only occasional bias tweaking. Remarkable considering the push pull parallel design.

The only minor criticism is the slightly over elaborate input stage. But this was done to facilitate connecting a phantom center channel speaker, which was a feature used back in the early 60s to combat the so called "hole in the middle" caused by the speakers of the day. An added side effect of this is the ability to invert the phase or polarity of the signal, which can come in handy at times...

I think most folks disparaging the amp, gave it away for peanuts back in the 70's and now are kicking themselves.

Or folks who cannot afford a pair...

Edits: 03/23/17 03/23/17 03/23/17

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