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Marantz 7C still good today?

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Originally posted by tomchaoda
With so many morden design of pre-amp, is Marantz 7C still a good pre-amp to do diy?

Does it also make sense to make it into balanced mode (as I am using Aleph 5 that can take both unbalanced balanced mode)?

Many thanks,

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system interaction,and your ears,should be the ultimate

judge, the parts can always be used for other projects.

an actual 7c will be so vauable, stock,any mod will result

in monitary loss
 
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I am with SY on this one, I have never heard a vintage pre-amplifier that sounded good by today's standards. Also building a balanced version makes it something else altogether.

Balanced output does make sense with the Aleph, so how about a transformer coupled line stage with balanced output and a 27, 56 or similar as the amplifier tube. Most sources are single ended so I would not necessarily bother with balanced internal topology or inputs.

I would also recommend a stepped attenuator instead of a pot.

There are lots of articles on the web for this sort of thing.

I wrote an article on a 26dht based transformer coupled pre-amplifier for Positive Feedback online a few months back. You might want to check it out.. (Or not..):D

I once owned a 7C and found the sound relatively inoffensive, but veiled compared to some other more modern designs.

Kevin
 
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Yes, amongst other things.. I think it is about the best of the lot, but that ain't saying much, unlike tube power amplifiers which achieved really high levels of performance long ago no vintage pre-amplifier even seems to come close to what is possible.

One pre-amplifier that seems to be more of an exception to this rule is the old Citation IV, but it is very sensitive to tube quality/condition. It was more transparent than anything else I tried.

Kevin
 
The M7C I built is with all the good components - Riken resistors, Jebsen copper-in-oil coupling caps, and Mundorf tubecap for B+ bypass. It just sounds great to me. Smooth as silk and powerful as a horse. Its soundstage is much wider and deeper.


Johnny
 
I just recently purchased a spice program and thought I would do a little tinkering with the Marantz 7 phono stage, I sub-ed the cathode follower with a 12au7 just to see what the results would be. I did some sweeps on the design and realized that I needed a grid stopper to couple the output to the 12au7, the results look pretty good so far. I'll have to play with the feedback network a little bit to come up with a good response.
 
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