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Marantz ESOTEC SM-7

HAL9000

HAL9000

i like marantz!!!
Hi everyone,

I have been working hard on a lot of marantz equipment The last weeks.
I had a SM7 ST7 of the esotec line, 4300 quad receiver and a 2500 for 300,-

I will post the SM7 and the rest later.

I got this Sm-7 amplifier from someone who hasn't used it in 20 years... you can imagine this most components are worn out. I switched it on, and everything was working very well. However on full power dummyload the Sm-7 started to oscillate Left more then right. problem was that one of the Big 80VDC 15.000µF caps was broken.

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bad caps.

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very bad solder points.

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overview is still in good condition.

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and it worked fine on low volume settings.

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New power caps 100V 15.000µF eVox riFa

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protect and VU amp.

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all panasonic
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I re-soldered the main amps and cleaned them, looks like new.!

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cleaning is a good thing!

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The Marantz sm-7 gave 2x250watts @ 8ohm load with almost 5.3A.

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Beautiful! Great job on the restoration; thanks for sharing it. :thmbsp:

I like the look of the Esotecs in black. All of mine are gold (or black-and-gold, in the case of the PM-4, of course). Hardly ever see them in black here, at all. Black looks meaner, more Vader-esque and "businesslike"; reminds me of some of the great Sansuis.
 
These are rare in the US, I rarely ever see them for sale. Like never.

Great info about Esotec over at the vintage knob, made 78-81...(ok to link? not sure abut rules?)
 
JT-3 said:
These are rare in the US, I rarely ever see them for sale. Like never.

Great info about Esotec over at the vintage knob, made 78-81...(ok to link? not sure abut rules?)
Click to expand...

These models are more popular in Europe. I only see gold plated marantz esotec in America. If you look on local marketplaces(internet sites)
you see a lot os PM6 sc 6 sm6 sc8 sm8 sm 1000

almost never sc 7 sm7 sm800.

They al need a lot of work!!! class A A/B 2x30watts etc But they really sound great!
 
Thanks for posting your work on these!

There are a few of the black pieces floating around the states. I have the exact same units and they play faithfully every day. They were something of a unicorn for me. I chased after them for years and it was worth it.

I seen a nice rack of these components st-7, sc-7, sm-7, sd-7 for sale in California years ago. All housed in a Marantz rack. Naturally I was flat broke at the time. That will probably be the last time I see that happen. :sigh:

This will definitely help when I decide recap my amp. I have looked under the hood of the sc-7 as well. Now that looks like a pita to work on.:yes:
 
Nice work there. Now you should get the rack handles for these :yes:

(bit of an esotec jonkey myself here, with a pile of MA-5's, sc&ma-6...
 
Hi Hal,

Compliments on great work!
I am wondering if you can help me with two questions as the hi-fi engine service manual is missing pages with that information.
1. What's the idle current value for SM7?
2. What is the wattage and amperage value of VU meter light bulbs?

Would be really grateful for your help.

Best,
Uros
 
I’ve owned one of these for a very long time. It’s a very coherent system that never gives the impression of being pushed to its limits. Powerful, smooth, natural, precise, but never clinical or fatiguing to listen to. It’s always a pleasure to switch it on. I’ll never grow tired of it.


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