Lytic Selection Help

Hi all...

I have a Marantz Model 25 integrated receiver that I want to have updated. I am bidding on a service manual at the moment, but in the meantime I would like to go ahead and purchase some new Lytics for it. I am not a DIYer per se - and will have someone do the work on it, but I would like to chose the replacement parts myself. I really enjoy reading about and learning about what components/parts are used in them.

The lytics in them are Nippon Chem 4700uf/50v. They appear to be ran parallel? Not sure what you call it, but they are wired together and shunted with resistors. They also appear to have bypass caps on the tag-board that the + attaches to (CPM .01uf/250v).

I think this amp uses Mos-Fet output - but I am not positive. I am looking to have it sound as tubesque as possible - I like very clear midrange with a solid bass, but do not like extremely bright highs - if that makes any sense. Any suggestions as to a good quality lytic to replace the Nippon, is greatly acepted.

"After acquiring the company, Superscope’s President Joseph Tushinsky aimed to expand the business and make Marantz a more general audio manufacturer. He looked to Japanese manufacturers to help him move into the mid-segment, and a trial production run with the Standard Radio Corporation of Japan led to the Model 25 modular stereo in 1966, joined later by lower cost models 22 and 28. Around this time, design and production (except for A-line articles) was switched from the US to Japan, and Superscope took a 50% participation in Standard Radio Corp. This corporation changed its name to Marantz Japan Inc. in 1975."

Cheers...
Nate
 

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anatech

Administrator
Paid Member
2004-06-06 8:31 pm
Georgetown, On
Hi bamadawg,
To the best of my knowledge, no one used mosfets in 1966. All the Marantz designs I am familiar with are bipolar or tube. Some new ones may be an exception.

If you are having the unit rebuilt, have the service guys choose and acquire your parts for you. Really. If they aren't to be trusted with that, you can't trust them to work on the unit to begin with. They will know what parts are suitable for this design.

This unit will never sound tube like. It's solid state. It will sound Marantz 25 like. It may sound nice when it's done but transistor design was not nearly as advanced as it is now. The transistors themselves have improved greatly on top of that. They did the best they could back then. Marantz design was generally at or near the head of the pack, they were ahead of their time. The SJ numbers are house numbers from Motorola. They will not tell you what they are as a base part #. The records may be gone by now.

-Chris
 
What you've got, bamadawg, is a really old but really nice SS amp that has a fair bit of history attached to it. It certainly ain't never gonna sound 'tube-like' unless you rip out the guts and replace 'em with a Dynaco 70.

RE: MOSFETS...1966 was about 12 - 14 years before power MOSFETS came into any real use. Certainly in '66 they were only an idea that was looking for a way to be reliably produced.
 
A few more pics...

I have no idea when Mos-Fet were introduced. I have them in my Marantz 2226B, and they are mounted on a heatsink like these are.

I know SS will never sound like a tube amp, I own those also. Jus that Mos-Fet powered are suppose to sound more "warm" like a tube amp. I have read of people using Vitamin Q caps in SS amps/receivers - I guess to further give it a "warm" sound.

Cheers...
Nate
 

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