Marantz 7C vs Marantz 7C

[crooner]

The kit version is mighty interesting. It is more exact in many ways to the VAC reissue. The VAC did have Clarostat pots, versus the Alps Japanese types in the kit version.

But the kit version did not have to comply with CE regulations, so the rear apron looks just like the original.

I wonder who wound the transformers for these versions...

 

[fredmarantz]

Yup - they look nice and pretty exact on the outside - and yes - the rear panel is very close to the original indeed.

How much, in fact, do you think the bumble bees contribute to the sound-character of the original 7?

I have an (almost) original 7, which unfortunately have had the volumepot replaced by some modern blue Alps-pot - could i do better? how? (besides getting an original- off course)?

best regards
Freddy

 

[crooner]

I most definitely think the Bumblebees account for much of the original 7's sonic appeal. The manufacturing process for these caps changed over the years, so the later versions are more reliable.

The other two important contributing factors are the selenium rectifiers, a controversial subject for some, and the volume control.

Carbon controls are preferable for collectability reasons and also for the sound. Shindo uses carbon pots in his ultra expensive custom made preamps.

Alps Blue Velvets are nice, but somewhat out of place in a classic Marantz 7, IMO.

Cosmos made 1/4 watt carbon pots but they will not last as long as 2 watt types.

Your best bet would be a NOS Allen Bradley. Military grade and they last forever.

 

[fredmarantz]

Thanks - Crooner!

I think that all my 7 will need to be 100% componentwise is to try to find that AB - pot. I guess that'll neither be easy nor cheap - ehh?

best regards
Freddy

 

[kcin]

Hi,

The pot on the 7c is notorious for being unbalanced between channels. It can be bettered but at the expense of originality. This one is about the only one available now from Digikey that looks and sounds the part. Expensive but alot more period correct.

http://media.digikey.com/photos/Precision Elec Comp Photos/KKB2541S28.JPG

 

[crooner]

I don't like the gold plated terminals on it though. A little anachronistic methinks...

 

[crooner]

Thanks - Crooner!

I think that all my 7 will need to be 100% componentwise is to try to find that AB - pot. I guess that'll neither be easy nor cheap - ehh?

best regards
Freddy

Yes, but make sure they marked "A" for "log" or audio taper. Some shady characters often try to pass linear pots as suitable for volume control. :nono:

 

[jstang]

I would love to build a 7K.....probably would not sleep till its done.....
jk