Fairchild 660 and 670?

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I never found the 5670 or 2C51 any good, when I tried plugging them into a sta level. Even though it`s quoted as a 6386 substitute, its anode is just different shape wise to a 6386. They`re not the same valve. In another thread on here PRR analized the curves of the 2 valves & came to the conclusion that they are not compatable. The choice is yours !!
 
Crap! RF is beating me! That does it. Where are my chassis punches.

The 660 was done in Rein Narma's basement. This was before he worked for Fairchild. So a few were built and sold by Rein privately, before Rein changed jobs. The first 660 went into Rudy Van Gelder's studio. The second most notable customer was Les Paul and Mary Ford.
Rein also modded mics for Rudy, converting U 67's into triode mode cathode follwers to permit close micing with a far away mic. This was when he was hanging with the folks over at Gotham.

After Rein joined Fairchild, the 670 was put into production. Although it is pretty much the same as a pair of 660's strapped together with the matrix switches, the chassis was laid out by some co-workers of Rein's, namelyGeorge Alexanderovich (sp?) and another guy who actually wrote me an email telling me to say hi to Rein when I did the interview. Little did I know that the email was from one of the original 670 designers, who might have seen our doings going on hereat the forum. His name was Irv somebody. George's name can be seen on the front a few owner's manuals that are floating around the web.

So you can see the difficulty we had in the interview as far as me asking him about the 670 layout, as he did not do it.

Irv Saul, I believe. George and Irv are both still around, so I am tyrying to get back in touch for some more insight.
 
"Irv somebody..." Ha!

Is it Irv Joel? I might be seeing him at a New York AES meeting later this month. I don't "know" him per se, but I've been hearing his name for years.

Whatever became of your Narma interview?
 
[quote author="Rob Flinn"]I never found the 5670 or 2C51 any good ... Even though it`s quoted as a 6386 substitute[/quote]
The 5670, 2C51, 6385, 6N3P and others are certainly NOT 6386 substitutes. The 6386 is a vari-mu tube - the others aren't.

Best regards,

Mikkel C. Simonsen
 
We've been over this a million times in this forum and the old one. There is no direct sub for the 6386. The M*nley tbar 2 x *AB6 thing is apparently the closest curve wise and sound wise. M*nley had some success with the 5670 and still makes the unit with it in there.

Remember PRR has demonstrated that a 12AU7 can be used in a vari mu comp to provide gain reduction to a point. The tube doesn't have to have a vari mu grid winding to be used for modest levels of gain reduction.

The CAA1589 limiter even uses 6AU6s, a sharp cuttoff pentode for gain reduction. I believe the 1589 replaced the AM864 in those industrial/commercial applications.

http://www.waltzingbear.com/Schematics/Misc/FAA_CA-1589.htm
 
[quote author="Rob Flinn"]PLEASE NOTE I DO NOT HAVE ANY 6386 FOR SALE & I DON`T KNOW OF ANYWHERE THAT IS SELLING THEM AT THE MOMENT !!!! If any does know of a source I`d be interested myself !!
![/quote]
Try this bloke..
6386_1.jpg

:grin:
 
There are probably some old products that used the 6386, but figuring out which can be tough.

It's like certain Peerless transformers have three different part numbers, if you know these numbers, you can really score.

Or if you know which Altec chassis' had the 217 D, etc.

There are people out there that know these things, getting them to talk is another story.
 
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