8 channel rack mount VU meter bridge

[ZekeProductions]

Hi,

I have an API DSM 24 (with a meter Bridge for the stereo outputs), The API DSM consist of 3x API 8200  But I also have 8x API 7600 all connected together and at mixdown its 32 channels.

To start off with I'm looking to build an  8 channel 1ru rack mount VU meter bridge to attach to the API 7600. At the back of the 7600 it has vu meter trs port and according to API the VU meter output can be connected directly to a meter. An additional driver isn't necessary.

My question is:

1. would I just need to build a 1ru case (say from frontpanelexpress.com) and place 8x VU Meters from Hairball audio into the case and thats it?
2. how would I power this up?
3. I have an MNATS PSU board would that work?


The end game ideally would be to have vu meters for my 8200 also and have 32 vu's in total.

Please Help!!

 

[PRR]

> 8x API 7600

http://www.studiomanuals.com/search.php?manufacturer=api

> 8x VU Meters from Hairball audio

http://www.hairballaudio.com/catalog/parts-store/panel-meters

Those Hairball VU meters are classic passive meters. Just wire them to the audio path. Use the dedicated VU-out if available. No power needed.

If you need the lights, any wall-wart *of the right voltage* will do.

 

[ZekeProductions]

Thanks PRR,

That helps. I actually have one meter at home so I guess I could try that and see how it goes first.

I guess to make a bridge for the others I would need a driver and a power supply?

 

[boji]

Hey Zeke,
I have some 8ch meter boards with peak led based off of a popular circuit if you are interested. They are unproven in the field. I tested one channel and it seems to work

 

[boji]

Actually I fibbed. These are my rev1's with no peak led. I've yet to fab the other ones. You're welcome to a few of these still if you wish, it would certainly save you some time and money if you needed to make 8 buffer cards.

 

[ZekeProductions]

Actually I fibbed. These are my rev1's with no peak led. I've yet to fab the other ones. You're welcome to a few of these still if you wish, it would certainly save you some time and money if you needed to make 8 buffer cards.

Thanks for the offer boji! I'll PM you to get more details and stuff

 

[ZekeProductions]

Hey Boji,

Your mailbox is full, but I got the boards yesterday.  Do you know where I can’t get the BOM from? Pm if you want.

 

[boji]

Deleted some old messages. I'll send you a pm!

I'll take a photo of the CAD work for you so you can correlate the part numbers this way. 
As for values, I suggest using the original schematic which can be found here: 
http://www.audiotechnology.com.au/PDF/TUTORIALS/AT51_DIY_VU.pdf

I see you'll need roughly for each PCB:
64      3.3k's
50      47k's and 10uf lytics
8        100ohm and trimpots (5k)
16 diodes
17 connectors
..and of course 8 TL071's.

You should probably add diodes going in and out of the rails, just to be safe. This is not on the PCB unfortunately...