DDA Q Series 24ch x 8 bus Monitor Console

[thecr4ne]

I've had this thing for a few years now, and today I finally fired it up for the first time. I got sound to come through (in ch1 out mains) but it has been far from thoroughly tested. One of the channel strips is bent, but I pulled it out and the innards look fine. A few of the VU meter lights are either out, or just very dim. I got all the needles to bounce though. The power cord has a splice in it and is connected with screw/spade connectors in the middle. Not sure what that's about, but it works (all wires numbered, thankfully). PSU says date of manufacture is 14-9-90. Assuming 14 Sept 1990.

Pics linked here:
http://imgur.com/a/kOZ72


I'd like to go through it as best I can fix anything that needs it, and eventually do some recording with it.

Anyone have any suggestions? Advice for what to check/ look out for? Care to gush or hate on this?

EDIT: So it looks like this is really a Q Series Monitor console, despite the S series master module.
See: http://ddaconsoles.com/pdf/brochure/q-series&moniter-brochure.pdf

 

[Davo]

Cool!

I've got an S series sitting right next to me... mine's only got two stereo aux channels.
What are the two strips to the right of the master?

I've gone through mine pretty thorougly... caps, fader replacements... plus I've replaced the summing
with Jeff's ACA/BO.  Mine also came with a beefed up PSU.  Really like it as a no frills little mixing board

Cheers

 

[thecr4ne]

What are the two strips to the right of the master?

The two modules on the far right are the "Aux/Foldback Master Module" and the "Effects Return Module" both are shown pretty clearly in the brochure linked int he OP. I'm still trying to wrap my mind around the routing options, and how I might employ them.

I just went through each input with a dynamic and got sound out of all of them. 2 of them have some issues, as they don't seem to be getting enough gain. I can get output, but the level is way too low.

fader replacements

Did you do a straight swap or upgrade to something else? If so, what did you use?

Most of the Faders are a bit scratchy, so I'll probably need to clean and re-lube. If anyone's done this before, any advice would be welcome. They look fairly open, but I don't want to thrash them. Based on some quick searching, Deoxit F series products seem to be the way to go.

plus I've replaced the summing with Jeff's ACA/BO

Forgive me, but can you provide a link or more info about this? I'm just digging into this and a lot of the terminology is still new. Not sure how much surgery I want to do, I kind of just want it functioning properly before I do any serious mods. But I'm open to suggestion.

Also, I stumbled onto an ebay listing for some S series Channel strips that I couldn't pass up, so I've got 8 of them on the way.  They appear to have the same connectors, and my board already has an S series Master module with Q series Channels, but I don't want to destroy anything, so if anyone knows whether I can mix and match, let me know.

http://www.ebay.com/itm/301784920211?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

[Davo]

Good luck with the faders!  I cleaned with De-oxit fader etc. before saying to hell with it and got new ones.  Got em from
Colin at audio maitenance:

http://www.audiomaintenance.com/acatalog/faders_carbon.html

With the summing section, I've tried different options:  stock, stock with upgraded chips, another summing section that I cobbled together and the ACA/BO..... I like the ACA the best

http://capi-gear.com/catalog/product_info.php?cPath=22_46&products_id=403

 

[thecr4ne]

Awesome. Thanks for the reply. I'm gonna have to do some homework before I get into the summing circuit, but the info in the link is a great help.

I just discovered I've got Phantom power problems. I don't get a signal from the mic and there's a lot of noise on the channel when I've got +48 on and a condenser connected (no noise with dynamic/ +48 on without mic connected) My first guess is Power Supply woes, but I haven't dug into it yet.

I also received the S series Channel strips I got on ebay. Haven't connected them to test yet, but I'm thinking I'll be happier with the Q series Monitor channels I already have. The routing on this thing still has me a bit baffled, but that probably means I just have more options. Besides, I figure 8 buses will be more useful than 4.  So I'll probably Sell them off once I make sure they're working.

 

[Graham]

Congrats on the Q series man! I've got two s/m strips here that have been ready to rack for years, just haven't had funds for the metal work. PSU is built and they are all wired up, just no case yet.

 

[tchgtr]

Cool! Now I know somebody else in LA is working with a S Series. I love mine, but wish I could find a few more channels, as I have 32 input frame, with only 24 channels in it.
Nothing but DDA love here.
A Q would be nice to have for the extra group channels, since I am mainly mixing on this board.
To the OP, it seems like you have looked at my write up on my S Series restoration. The two boards are very similar, and I would recommend a total recap, but leave the op amps alone. I put some bypass caps on the master and group channels, and that gave the sparkle and clear transients I like. It vaguely reminds me of a trident 24 I once worked on, but that thing was in pretty sorry shape, right up to the moment it was high-jacked out of the studio by gun-toting bandits. Fortunately it was not my session, and the engineer was OK, but they forgot to take the power supply! Sheeesh!
Anyway, change all signal caps to 220 uf, and maybe play with some WIMAs MKPs in place of the EQ caps, rebuild the PSU, and enjoy!

 

[thecr4ne]

Cool! Now I know somebody else in LA is working with a S Series. I love mine, but wish I could find a few more channels, as I have 32 input frame, with only 24 channels in it.

Well, I just happen to have 8 S Series Channel Strips that I decided not to use. If you'd like to fill in your console, maybe we can work something out.

 

[thecr4ne]

Hi all,
Long overdue update.

I reached out to tchgtr and we were able to meet up. He had a look a my PSU and confirmed that it's in solid shape. I re-soldered the PSU end of the Power cable to get rid of the gnarly spade connector splice in it, and all checks out there.

I unscrewed all the strips from the chassis and removed the master and monitor strips to get a look at the inside. The first thing I noticed was an orange wire cut off the back of the incoming power connector. I haven't had a chance to poke it with a meter yet, but assuming Orange in the board is +48 as it is in the PSU, this is likely the source of my Phantom problem. 
Pic: http://i.imgur.com/hJl2wWY.png

There are two of each other wire coming off, I followed the bunch without the orange (blue, brown, green)to where they are soldered to the board, but things were tight and I couldn't get a good look at whether there was a spot where the missing orange wire should be.
Blurry pic: http://i.imgur.com/mlE9WVs.jpg

I also noticed a spot where two pads had very obviously been un-soldered. Looking at similar spots further down the line, there should be an Orange and Black wire soldered here and connecting to either a monitor strip, or the master strip (need to double check)
Pic: http://i.imgur.com/pAaEIWG.jpg

tchgtr, if you get a chance, I might ask you to crack open your board and have a look so I can reference something that's actually functioning and see if I can figure out what I'm missing.

I also pulled a few strips that weren't passing audio very well. Sound came through, but no real gain and the faders seemed not to do anything. Turns out one of the channels is missing a capacitor (c48 I believe) leads are still soldered in but broken off. And the other I'm not sure about, but a few of the electrolytics appear to have small holes in the top that make me suspicious. They're not bulging or exploded, so maybe this is nothing.

I'll try to have another look this evening and take some more/better pics to post tomorrow.
Cheers.