SCHEMATICS for v372D needed PLEASE

[sonolink]

Hello everybody,

My girlfriend gave me to v372D units as a birthday present (I swear...) and I'd like to rack them up as mic preamps but I don't have ANY info on these babies.
Could anyone provide schem, psu specs or help with this please?

Thanks
Sono

 

[sonolink]

Another pic

 

[moamps]

Here is the schematic.

Edit - correct sch uploaded

 

[sonolink]

Thanks Moamps!!!!!

 

[sonolink]

I've had a look at the docs. Although I don't know german I think I can grasp what matters

Am I right to think that these units are Dual, meaning they are 2 mic preamps in one?

 

[synthiaks]

I hate to be a party crasher  here but this is a summing amp and as far as i understand the info its 0-15dB gain depending on the resistor.

The V672D would be the one you are looking for. Hated by some for its Dünnfilm ICs

 

[sonolink]

I hate to be a party crasher  here but this is a summing amp and as far as i understand the info its 0-15dB gain depending on the resistor. The V672D would be the one you are looking for. Hated by some for its Dünnfilm ICs

http://audio.kubarth.com/v372rack/index.html

Now that I have the schems I'm looking to find the necessary mods to comnvert it into a mic preamp.

Anyone?

 

[synthiaks]

...As said, the schematic you are following is for a summing amp. The pictures you link to are for theV372/1 and not the V372/1D from the schematic.  The /1, /1D and D can be quite different even though they all have the V372 in common. The V672D is a mic pre so the V372D could also be one but then the posted schematic is not for this amp.

I still think what you have is a Summing amp, send us a picture of it open. and we will know.

s

 

[synthiaks]

I should correct myself the V672D is a dual multi purpose amp that can be wired to be a lower gain Mic pre.

 

[synthiaks]

And after doing some research the V372D IS a dual Microphone pre. But the schematic you got is NOT for this Preamp.

 

[[silent:arts]]

And after doing some research the V372D IS a dual Microphone pre. But the schematic you got is NOT for this Preamp.

Not really. It is a dual multi purpose amp like the V672D

V372D Datasheet with pinout

However, we need to see yours open.
Seeing the dual row connector on your modules it can't be a V372/1D

 

[synthiaks]

Interesting! Thanks for the PDF! On the down left corner it say Ausg 1/72 wich i guess is 1972. I guess this make the V372D discreet. The V672D has the Dünnfilm IC wich is just a thin ceramic wafer with SMD transistors on it.

Then the V372D will be more like 2xV672s in one

Make RGK 2,6K and you have the maximum gain of 42dB.

/s

 

[sonolink]

Thanks for the feedback and interest Synthiaks and Volker (and for that pdf I've been looking for so much!!!)

I've opened both units and took some photos. I couldn't make the photos look right (they showed upside down always) so I've uploaded them to another site.

Here they are. Please tell me what you think these units are. They both seem to carry the same TXs.
Thanks again for your time and help

 

[synthiaks]

First impression would be those Electrolyts should go, Im sure one or two are leaking. Second would be that i was right, this is a discreet amp. And Third i would say that it could be the right amp for last PDF.

S

 

[sonolink]

You mean the blue red and yellow ones? You say a complete lytic recap right?

If so should I look for "vintage" replacement caps or modern good quality ones? I guess that's a tricky question....

About the pdf provided by Volker I understand I should provide 24vdc power (500 ma? ) balanced input and output, unbalanced input and output and gain pot following the table provided right? (2k6 for max gain of 42dB)

To provide phantom maybe protection caps at the inputs (100uF/63v?) and connect 48vdc through a switch at the inputs?

Finally If all the above is correct,  any ideas to implement a pad?

Thanks a lot for your help and time
Sono

 

[[silent:arts]]

You mean the blue red and yellow ones? You say a complete lytic recap right?

If so should I look for "vintage" replacement caps or modern good quality ones? I guess that's a tricky question....

Yes, replace all lytics. Take new ones, nothing old vintage!

About the pdf provided by Volker I understand I should provide 24vdc power (500 ma? )

24V 55mA each Channel

To provide phantom maybe protection caps at the inputs (100uF/63v?) and connect 48vdc through a switch at the inputs?

No protection caps needed. You have an input transformer.

Finally If all the above is correct,  any ideas to implement a pad?

Why? You have pinouts and RGK for 0-12dB, 12-27dB, and 27-42dB.
The difference between 12-27 and 27-42 is how the output transformer is wired, RGKs are equal.
So, find a way to switch the output transformer and you are setup for 12 to 42 dB ...

 

[sonolink]

Excellent!! Thanks a lot Volker

Cheers
Sono

 

[sonolink]

I forgot to ask: screw pots on the fromnt panel are for calibration of something?
Cheers
Sono

 

[[silent:arts]]

like it is written on the front panel: +/- 1,5dB ...

 

[sonolink]

like it is written on the front panel: +/- 1,5dB ...

Oh, so it's like for fine adjustments when a stepped pot is used?

I was wondering if it's possible to add an output pot. Any ideas how to do that best?

Cheers
Sono