HD not a stable platform? ADC issue + more! Help!
 

Hi, long time viewer, first time poster. I've hit what could be a hardware problem and i'm a little freaked. I'm also a little upset that im having these issues at all seeing as how we pay big $ for HD to not have to worry to much about these things. Hopefully its user error here, I'll eat my words.

I have an HD 1 Pci-x system running 7.4 on a Dual 2.7 PPC G5 Mac using an Lynx Aurora 8 as converters.

The system is pretty stable for the most part, but it has certainly been a little glitchy lately.

The big problem im having, that i'm worried might be hardware related is that ADC does not seem to be working correctly at all.

I was mixing yesterday and I threw a waves c4 plug on one of my kick drum tracks and noticed it immeadiatly started to phase. I checked to make sure ADC was on and it was. Opened up ADC view in the mix window knowing the plug falls WAY under the 4000+ samples that ADC can fix and noticed that the numbers were not lining up at all. Uhg...

For instance, the delay on some tracks would be at like... 653 and the copensation would only be like 148. What? Also some tracks were showing compensation of like 400 samples for tracks with no delay.
SHould I have to use offset constantly, and if so, tsk tsk digi. That should be automatic.

All my settings seem to be in order...CPU usage, Buffer size (at 512 I belive) etc.. just about all of em are at default.

Oh and I'm mainly using RTAS. is that an issue?

Please help!

Re: HD not a stable platform? ADC issue + more! Help!
 

Oh, and I was reamping yesterday to and noticed some pretty long latency? how much is normal? How far behind should the reamped track be delayed from the original track if the mic is pretty close to the source (about 1 foot)?

Re: HD not a stable platform? ADC issue + more! Help!
 

If you have 40 tracks with and no plugs inserted and then insert one plug which causes a 245 samples delay. That channel will not be adjusted.
It will indicate ( i think in yellow) that 245 samples is being issued. ALL THE OTHER tracks with NO plugs inserted to them will ALL be delayed by 245 samples (Displayed in Green) That is correct behavior.

ADC itself, especially when using DSP Cache is extremely buggy and the culprit of much pain and agony. Not sure who the culprit is in your setup. you would need to provide us with more specifics. But I doubt that it is hardware related.

A good rule of thumb when using ADC is to double check everything, every now and then. It sucks yeah but until digi gets a hold on ADC's mind of its ow that is the ONLY workaround.

Re: HD not a stable platform? ADC issue + more! Help!
 

I see a couple of things right off.

1. RTAS plug ins on auxes, master faders, and after TDM plug ins on audio tracks will be double the hardware buffer setting, needing x samples off the TDM bus and x samples back on the TDM bus. If you have the hardware buffer set at 512, RTAS plug ins will require the other tracks to have 1024 samples of delay compensation. Placing the RTAS plug ins before TDM plug ins on audio tracks do not normally require compensation as they are taken care of by pre-buffering the audio stream when pressing play.

2. Since you are using a HD1 PCIx core, you have no Accel chips on that card. That means that you can only set the ADC engine to short (1023 samples) due to the long engine requiring an Accel chip to operate.

If you are going to use mainly RTAS plug ins and want to have ADC work properly on auxes, masters, and after TDM plug ins, you will need to either set your hardware buffer to 256 or lower, or purchase an Accel card for your system.

Hope this helps...

Gil

Re: HD not a stable platform? ADC issue + more! Help!
 

But I do use the "Long 4095" setting. Is it that im not supposed to use that option? Or should it not even be an option?

Alright, an easier way to do this would be to ask this question simply. I am getting at least one more process card soon(probably 2), until then what should I have my settings at if I generally use RTAS plugs (waves diamond bundle mostly) 99% of the time and need ADC to work properly?

And...How much more power will I get with another process card, and will it help the ADC engine? or does it not matter?

Re: HD not a stable platform? ADC issue + more! Help!
 

Hi,

Have your delay comp set to long!
delay comp is influenced a lot by the hardware buffer setting!! the higher the buffer setting, the longer the delay caused by plugs. its a balance between the right buffer setting for your needs and whether the plugins that you use can operate on lower buffer settings, some of the high processing plugs don't like or won't work on very low buffer settings. i use 512 buffer setting and it works fine for most things. If i am programming or playing in live parts i will lower the setting or disable delay comp on just the track i'm playing.

Its a very complicated subject and you need to read the entire section of the manual relating to delay comp. then read it again:-)

Chris

Re: HD not a stable platform? ADC issue + more! Help!
 

Yes, I have read the manual, a few times actually. And I feel I have a pretty good grasp of the ADC engine. But I would like to know more, rather an in-depth look at how it works, and how to properly use it.

The phase scope is my #1 tool in making a record sound good, The idea that once I phase balance a song right off the bat, it might go right back out due to latency issues is upsetting to say the least.

So I don't mind doing the legwork, learning the "ins and outs" of ADC. Just point me in the right direction. And any tips that will expedite the process are hugely appreciated.

Thanks