Channels 7 and 12 - Noise

[StudioG]

New to forum.. great find....
Recently purchased a D8B from ebay with 5.1 os, Cpu was problem at first, but now boots up fine. However, I'm getting chattering sounds/hissing on Channels 7 and 12...wondering if this could be related to my MDR recorder, or my DIO/8 cards. I thought it might be my word clock in the D8B so I powered down the CPU and reseated the word clock, but didn't seem to help. Do you think it would help to replace the stock word clock with an Apogee work clock card.. any thoughts.. Makes the noices on play and record. Doesn't make noice when multi-track recorder is turned off..
The board when I purchased it came with the less expensive OPT/8 cards. I removed them and installed higher quality DIO cards and was told it would be better for sound quality.. I bought them online new, sealed in box. I thought they could be bad. I bought 6 of them, what are the odds of all of them having a problem......if I put the cheaper OPT cards back in, the noice goes away, but I don't have enough of them to furnish everything for a full test. Thanks for any help... going crazy.. already spoke to Mackie about sending out for repair...don't really want to do that yet...
PS If anyone knows of someone I could talk to about, or talk me through some issues would greatly appreciate....

[anyhorizon]

Firstly, whoever told you that the DIO-8 cards are of a higher quality than the OPT-8 cards is misguided. In fact, if ADAT is your method of interface, the OPT-8s offer way less hassle.

Secondly, make sure that all the channel filters are turned off. They are prone to chattering. Once they are all turned off, save your startup session file so that they stay that way when you re-boot.

Thirdly, if you must keep using the DIO-8 cards, make sure they are all the same EPROM vsn., preferably vsn 2.1.

Peter

[anyhorizon]

BTW, it's unlikely that the stock word clock card is the source of your problem but in answer to your question, the Apogee word clock card does offer superior performance.

Peter

[StudioG]

First, I would like to thank you for your quick response. It's greatly appreciated....
I did in fact turn off all the channel filters and I did check the firmware on the DIO cards and they do match. The only problem with the Opt cards is I don't have enough of them if I go back to using all Opt cards.. Since I have all the DIO cards I really should try to find out what the issue is.. Wondering if it is an issue with the MDR also... thanks again..g...

[anyhorizon]

Well, if you unplug the ADAT connections from the MDR to the d8b and the chattering/noise stops then the MDR would most likely be the problem. You could also try swapping the cards around at both ends and see if the problem changes positions. Make sure all Eqs, compression and gates are disengaged on all the d8b's channels. There are many sources to check. You should start with the desk totally normalized.

Peter

[anyhorizon]

Oh, failing that, go to the desktop and flush all startup session files down the toilet, power down and reboot. The d8b will create a new pristine startup session but you will still have to turn the channel filters off and save again.

Peter

[StudioG]

I've done what was suggested.. maybe I'm not understanding what's normal and not normal with this board.. I've switched out from dio8 to opt8 cards.. hoping the the problem would go away.. there is a static noise coming back through the tape returns from my MDR... on ramdom channels.. seems to be the worst on the 1st eight.. Maybe I'm doing something with the board that I'm not supposed to do. Here's the procedure I'm using to test the in-out and routing of the board: I'm taking any given channel on bank 1..lets just say Channel 1.. I hook up microphone and I select tape sends 1-24 from channel one, I arm all tracks for record and as soon as I start speaking into mic, the first 8 tracks on MDR start going into the red on the leds meters. I switched to bank 2 that sends returns back to board and getting hissing, static, crackling noises.. If I start shutting down tape sends.. noise seems to go away.. I've turned off all channel filters, but doesn't seem to help..Normally I would not be sending channel 1 to all 24 tape sends...but was just testing....should this board normally be able to handle it.... if so could this be my MDR or software issue... Thanks again and appreciate any advice....

[synthjoe]

Is your clock sync OK between the d8b and the recorder? I have no idea exactly how to check it, but based on your description you'd want to find out and confirm appropriate working of the clock, I think... Just my 2 cents.

[KyRange]

Which MDR are you using?

[StudioG]

Thanks.. clock is ok... and the MDR is a Mackie 24/96...