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FS: Fred Forssell Console Master Section - All Tube!

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atavacron

Well-known member
Joined
Jan 28, 2009
Messages
344
Here is a solidly built custom job from Fred circa 1994. All tube. Four 2-channel sources including the input from the summing amp of whatever console (or summing rig) this becomes mated to. Master fader. Mix output to DAW and/or tape, both of which can come back in to the source select. Two sets of monitors with stepped attenuator.

Photos: https://drive.google.com/open?id=1uIvZLsaaMH9TWCx9i6hrt6tLFjAk47ge

Acceptance of solo bus from the desk as well as solo DC trigger from the desk. Mute and dim functionality as well...a little unsure how the mute works.

I was going to use this with my Trident 24, but will be going a different direction due only to a very tight rack layout around the desk. I believe it was built for a MCI JH-5XX desk originally, but there is nothing particularly MCI about it. Honestly it is plug and play with any number of control room architectures.

The 56-way Elco was made especially for this unit and the pinning for it is listed in order right there on the unit – just throw on some XLRs or pin to another connector. That rotary fader is really nice, clearly someone damaged the original and this was its replacement, with humorous-but-solid perfboard bracing. I don't think those panel mount trim pots on the rear have a purpose, but they are free with the unit and look like nice ones.

I interfaced with Fred and he was kind enough to dig up the closest you'll have to the schematics for this, which are several iterations of design work. The last one  is obviously what he built from. The wiring looks a little disorganized, but once you spend a minute looking at it in person, you realize he was just taking the shortest possible path to everything, and that it's all quite safe and shielded and solid. But you could get in there and zip tie things for tidyness pretty easily. I do not know why left and right are reversed on one of the Sources, but it is easily corrected.

And yes, it sounds glorious.

(Edit 9/30/19:) $1450 plus shipping ...free shipping within the continental US.

(how does one put a bunch of pics inline in a post? i tried using google drive links and had no luck)
 

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pucho812 said:
do you have any photos of the schematic?

I think it may be an intellectual property issue to post it, and I don't wish to ask his permission out of respect. But of course the schematic (and its iterations) will be provided to the buyer.
 
ruffrecords said:
What tubes does it use?

Cheers

Ian

Pretty standard noval 12s. Well chosen though, grey plate RCA if I remember correctly. Check the photos on my Drive.
 
Also. People working in tube line stages will have more insight into this than I, but I'll bet that the mix amp gain could be adjusted to provide makeup gain after a summing resistor network, aka turn that first stage into a summing amp. It's pretty close to unity as built if I recall correctly. Not guaranteeing anything, just a thought.
 
It's now up on eBay/Reverb at $1675. 10% off for anyone from Group DIY if you message me here.
 
pucho812 said:
I would buy the schematics

In the early 1990's (around when this unit was built), there was a line amp circuit that Fred published in the old 'Glass Audio' magazine.  It was designed by him and Bascom King and had an improvement in drive cabability over the so-called  'White' follower.
I would imagine this unit uses that topology so, look for an old copy of that issue or, maybe ask Fred if he has a copy of the article.
It's a nice circuit and I'm sure this unit sounds awesome.

Bump!
 
Winston O'Boogie said:
In the early 1990's (around when this unit was built), there was a line amp circuit that Fred published in the old 'Glass Audio' magazine.  It was designed by him and Bascom King and had an improvement in drive cabability over the so-called  'White' follower.
I would imagine this unit uses that topology so, look for an old copy of that issue or, maybe ask Fred if he has a copy of the article.
It's a nice circuit and I'm sure this unit sounds awesome.

Bump!

it's on his website....

http://www.forsselltech.com/media/attachments/TLD.PDF
 
pucho812 said:
it's on his website....

http://www.forsselltech.com/media/attachments/TLD.PDF

Ha!  Well there ya go 👍  Don't know if that's what's in the master section but I bet it's at least similar. 
 
Bumped at $1475 for y’all, it’s more via other online spots.

You know you wanna tweak the gain on this.
 
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