Update!! 4x Custom Gates Sta-Levels from National Recording, NYC

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cletus monroe

Well-known member
Joined
Jun 18, 2004
Messages
65
Location
Brooklyn, NY
Let the Scooby Doo Mystery begin!  

Can't tell you much about these because they are still at the shipping place.  Happened upon them by accident searching for transformers.  The gentleman I bought them from said they came from National Recording, NYC.
Langevin in/out transformers and four tubes per circuit make me think good things!

Bar the sharpie pen writing of the tube designations, for a custom job, the symmetry of the back plates' housing of the caps/tubes/trannies is pretty darn good.  

If these truly are custom, and not some uno o' a kind langevin prototypes (now wouldn't that be fun?),
then I feel like someone finding one of my diy pieces 40 yrs. from now.  

This community has grown immensely, and thanks to that, there are a lot more amazing custom pieces of audio gear out there for the future generations.  Whoever built this, from first glance, had some pretty good taste.

If anyone is interested, I'll post pics of the inside once they arrrive.

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First of all, the input transformer is a UTC A series, likely be an A-10.  The output transformer is a TF-129 which was used in the Langevin 5116b; no tertiary feedback winding.  I suspect the output stage is very similar to the 5116b: TR-129, 12AX7a, and 12AU7 in place of 12BH7.  The 6AL5 is the signal rectifier.  At first glance it appeared to be perhaps an earlier version of the AM-5301, but I'm quite sure it was not made by Langevin, they would not use UTC's.

Easy matter to add metering and gain controls.

It appears to have all the right ingredients to sound superb.
 
those look familiar... if they were from National they were probably built by Eldo Luciano (who has retired back to Argentina and I have no idea if he is still alive).  The build quality and materials are consistent with things he did.  When I worked at National all the 1/4" and 1/2" machines were Ampex 300 and 350 machines, 3200 series duplicators etc.  National (before it moved to the west side airline terminal) was in two floors of a building at 57th and 5th, they had the studio at the Edison Hotel that Lenny Kravitz eventually took over, the East Side film center where the Stones' Gimme Shelter was mixed, and a large cassette duplication facility in L.I.C. about six blocks from the exile shop where I spend a lot of time these days.  Eldo built all the large recording/remixing consoles (Studio A and B and the film mix theater at 57th street, the one at the edison and the film console at the film center...  he also built at least two 2" machines (16 track) and a whole variety of outboard gear, amplifiers and so on.  This was quite common.  Most of the big studios had huge shops and personnel that could make just about anything.  API, Langevin, Fairchild, Electrodyne, MAP, Melcor etc geared their modular products to these shops... Datamix consoles came up from that ethos...  api started building whole console product as opposed to customs.  In those days recording engineers were actually engineers or at least had an understanding of the engineering and the chief techs had come out of one of the military services often having done time as a radio engineer...  ...so this piece would be typical of that time.  Eldo built things to last...  he typically did not take an app note and copy anything in particular so do not expect that thing to be directly related to anything in particular.  Langevin made good transformers and attentuators so they turned up everywhere...  a console I had and used for a while was built up from Fairchild line amplifiers, Langevin passive EQ modules and rotary attenuators, and Painton faders...  you'll have some fun figuring out your particular beast - there will be zero documentation.
 
Thanks for all the background John.  Ironically, I was going to email you if nothing turned up from this post.
Your name popped up when I was searching "National Recording".  I also learned that you used to engineer for All Platinum. Wow!  That's one of my favorite labels. 

Found this link mentioning Eldo Luciano. 

http://books.google.com/books?id=WiQEAAAAMBAJ&pg=PT27&lpg=PT27&dq=eldo+luciano+audio+tech&source=bl&ots=sj01luQH0F&sig=rnDZfyQOaChbSQt-Lak40Y3DHAM&hl=en&ei=r4jcS8r3Lo-g9QSEoITKBw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CAsQ6AEwAA#v=onepage&q&f=false

Thanks to everyone else who posted as well.  I'll update with some inside pics when they arrive.
 
I would start by tracing down the schematic,which souldn't be too difficult as the unit is probably point to point wired. This will very likely reveal a classic "vari-mu" scheme typical of most similar compressors of that era. (Altec,Gates Sta-Level,G.E Unilevel,Collins...). Then you can add IN/OUT level controls,variable attack/release/treshold and metering by using the Altec or Gates schematics as a source of inspiration. Some photos of the inside would be great.
Looks this is an historic piece.
How lucky you are... 
 
A trace of the schematic is definitely on order.  I'm not sure how much I'm going to modify these.  It all depends on how they sound.  Why didn't the original builder add these features?  Money, design philosophy?
Meters are a funny thing.  I would never get rid of one, but I don't mind their absence.  Lights, now that is a must!

I kinda love and am very intrigued that these units were built with nothing but 250ms and 1s release switches on the front panel.  Oh, and four lights.  Separate but equal!  They should arrive Wednesday along with some altec power supplies thrown in for good measure.

I can't wait to see the inside.  I don't think I've been this excited for a reveal since I saw my first pair of boobs..... in person. 

 

 
 
Hey Dudes,

Just got them in the mail along with some power supplies that need to be rebuilt.   
Here's the inside.  The last pic is in honor of just watching Excalibur again since I was 9.  The Dragon's Breath.  I must admit, boobs are much better, but the test button gives a money run.

Can anyone say point to point! 



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Stagefright13 said:
Holy Cow looks like "Moses's DVD Player". (Quote from Alien verses Predator)

;D

gridcurrent said:
First of all, the input transformer is a UTC A series, likely be an A-10.  

Close, they're A-11's!  Well, two say they are.  

Here are pics of the crazy power supply array.  Not taken were pics that of the altec power supplies that I'm now convinced are also part of this as well :

Uses two 5V4's.  This is also for two sets of 4.  I wonder where that other set of 4 is or if it they even exist?  Father.  Yes son.  What does regret mean?  Well son, a funny thing about regret is......  The compressors plug into this unit using 4 prong, flat connectors.  All the units also connect together.  Jeez, how about one big box?

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Big boy time:

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There are two of these:

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I'm going to do my best to trace the circuit and post it here for hopeful review and insight from some of you circuit gurus.    




 
I spoke about this with one of the engineers from National who was also there back in the day ...The mixing consoles were made in house and the ones in Studio A at 57th street and at the studio at the Edison Hotel (at least) had four busses and the busses had limiters - the pile you have was probably out of Studio A...  I sort of recall that panel in the bottom of one of the racks at 57th street...  also possible that this was on the film mix room there but more likely Studio A...  there will be no docs.
 
Alright, here's a rough trace of the circuit. Still need to check for errors and fill in some blanks...

Looks pretty standard for it's time. So meters and maybe a threshold pot were external?

Wonder what they looked like...
 

Attachments

  • CLAYS COMPRESSORS1.pdf
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Not a familiar clone at first glance.  I've poor memory of the Presto 41-A circuit, or the CCA(?) LA-1 circuit; seem like they are more in this direction. 

Meters probably in the original console, probably standard VU. 
Probably 600 ohm Daven pots on input and output for threshold and output.

Huge caps in the feedback path.
1st coupling at 0.01 seems small, probably to limit low frequency distortion audibility. 
Non-standard placement of the release shunt resistors. 
coupling caps to side chain are very small; keeps bass from pumping and lows distortion down. 
12AU7 with this output trans means the unit is more of a comp, and probably not capable of limiting ratios due to operating level. 

Looks like a mash-up of the Langevin 5116-B preamp with an Altec 436A front end; not really either straight-up. 
 
Well Shaggy.....

It turns out these dudes are not actually ghosts, but 4 Gates Sta-Level copies. 

Here's the almost complete circuit.  You can see that the release time switch hasn't been traced yet.:

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And the Sta-Level circuit for comparison:

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I would say those are pretty similar.  I'm stoked and definitely going to redesign the front panel to resemble four mini Sta-Levels.  It seems Eldo did base some of his designs on preexisting products.  I ain't complain'!  It's gonna be fun to compare these to the real deal....someday.     
 
Nah, totally not.  I stand by my previous answer.  If that's a Stalevel clone, everything's a Stalevel clone.  6386/6BC8 and 6V6/12AU7 comparisons are not even on the same page. 
 

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