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FS:4x312's in 1U rack

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spica

Well-known member
Joined
Sep 13, 2006
Messages
192
Location
Los Angeles, CA
I'm slowly moving my preamps over to 500 series so I'm letting go of my regular rack mounted pre's. 

I built the 312's some years ago using Fabio's PCBs.  The input transformers for all channels are Cinemag 75101's.  The input impedance can be switched for either 150 or 600 ohms via a relay I added that is controlled by a front panel switch.  The first two channels have 2520 opamps, and Cinemag CMOQ-2L output transformers.  The second pair use 1731 opamps and Cinemag CMOQ-2S output transformers.    The front panel mounting holes didn't quite match the holes on the enclosure so there are a couple extra half-holes on the front panel.  I have the front panel express file and can send it if you would like to make your own panel.  The switches are all off-board so making your own from scratch wouldn't be hard if you are so inclined.  The switches on the back are for switching from mic to line inputs.  Never ended up using those.  Gain pots are quality Omeg types and all switches are C&K's.  The lead dress isn't the cleanest inside but it looks, sounds and feels great.

Asking $1100 including shipping to the lower 48 (US) - less than what I think it would cost to build again (parts cost, enclosure, etc).  Open to shipping world wide but would need to check on shipping prices.   

The pre's sound great, are quiet, and have been trouble free since built.  I am located in Los Angeles if anyone is local and wants to see them in person.

EZ1290's are sold.

May also be open to trades for stereo compressors (stereo LA3A/33109/api?) or EQs that are either fully built or complete/mostly complete parts kits or 10/11 slot 500 series racks. 

Feel free to ask questions.    Pics will be up soon.
 
Sorry to derail the thread. If you built these where did you find that cool green lamp? Again sorry for the derailment.
 
The 1290/1073's may be spoken for. 

Hi Ding, I'm not sure where the lights come from but KMB might be able to shed some light on that.

-Tony
 
ding said:
Sorry to derail the thread. If you built these where did you find that cool green lamp? Again sorry for the derailment.

it seems like a standard "Green Jewel light" commonly used in guitar tube amplifiers.
see here:

https://www.banzaimusic.com/Jewel-Lights/
 
Whoops said:
ding said:
Sorry to derail the thread. If you built these where did you find that cool green lamp? Again sorry for the derailment.

it seems like a standard "Green Jewel light" commonly used in guitar tube amplifiers.
see here:

https://www.banzaimusic.com/Jewel-Lights/

Not exactly that, but close. These I found at a electronics salvage. From my memory, they are glass, and they are smooth without  "diamond cuts".

I'm sure I still have a handful of them if you want some.
 
Again huge apologies for the de-rail. I imagine that can be annoying. Yes, that would be awesome. I have been looking for something like this but have not found anything. Everything is big and diamond cut. I will PM you. Now back to your regularly scheduled program.  :)

BTW nice build! Also.....POST 420!!!!!!!!!!!!!!
 
The 1290's are sold. 

Any interest in the 312's?  They sound great and I usually preferred them over anything else on just about everything. 

I am in the market for a good desoldering tool and multi-meter so I could be interested in a partial trade for those also.

-Tony
 
Bump.

Offers?  Interesting trades?  Compressors/mic's?

Not in a huge hurry to move them but would like to fund other projects.
 
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