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Cary B. Cornett
01-22-2005, 12:54 PM
I have been experimenting more with parallel processing in my mixes, and I need to understand some things better. For example, in one mix I assigned drums both to output 1 and output 2 (with 2 assigned back to one), and inserted an Ultrafunk Multiband compressor in output 2. The compressor apparently introduced a difference in latency that caused some phase cancellations in the output sound. The "cure" was to insert another multiband compressor in output 1 that was set to do no processing (not "bypassed", though).

First I need to understand about latency handling of different fx api's. IIRC, latency is automatically compensated in SAW native plugs, and possibly in DX plugs as well. Latency is not compensated in VST plugs. Do I have all this correct?

Is there a way to do parallel processing without having to insert a "dummy" of the same plug in the "unprocessed" path to eliminate latency differences in the two different paths?

Can the JMS send/return plugin be used to facilitate parallel processing within a single channel or path, and if so, how?

thanks in advance

Cary B. Cornett
Cornett Technical Services / Chinese Puzzle Recording

AudioAstronomer
01-22-2005, 01:22 PM
DX and native saw plugins are compensated.


to use JMS for paralell processing put the latency compensator on the track with the plugin and set it to the latency the plugin introduces, this should be in the plugins manual.

it's that simple :)

Meanwhile Why not try out Sonoris multiband compressor! no latency and fantastic sound! This coming from a man (myself) who cant stand multiband compressors in general :)

Jay Q
01-22-2005, 05:58 PM
This coming from a man (myself) who cant stand multiband compressors in general :)Why, pray tell, can't you stand them, Robert?

Jay

AudioAstronomer
01-22-2005, 08:29 PM
Why, pray tell, can't you stand them, Robert?

Jay
*shrug*

Our goal: pristine awesome audio quality.

Basic rule: every process degrades audio quality.

Multiband compressor: Split audio into X bands (x processes), apply dynamic gain reduction (another X processes), perhaps limit (yet another x processes), sum individual bands back together (another x processes minus 1), apply final gain.

Eh.

I can see it's use for "fixing" things, but I dont put up with that here. My rule of thumb is if you broke it, you fix it. If I broke it, Ill do everything I possibly can to make it right. If Im "breaking" the sound im after then processesing it even MORE is probabaly the last answer.

Just my opinion :) BUT! Ive really had fun with pieters multiband compressor. It sounds much more natural than what Ive heard from the likes of waves, sonitus, voxengo etc... I will buy it, I will recommend it, but will I use it much? Eh probably 1 in a 100 chance.

TotalSonic
01-22-2005, 09:26 PM
I agree in basics with Robert that multiband comps should be avoided in general as they are an easy way to mess up your mix if you're not careful with their settings - but multiband comps definitely have their uses. To me they are not "go to" devices but "problem solvers" - i.e. they shouldn't be used as a default but as a way to fix things that can't be solved by other means. One case in point: tracking my string quartets violinist with a Schoeps sdc (which after the session we realized really wasn't suited to her instrument) on one piece her part has her jumping from her lower octaves (which sounded great) to her higher one (which jumped way too far out of the mix and sounded brittle). EQ'ing just made her lower octaves sound too muted and dull - thus a multiband comp to the rescue. Another great use for multiband comps is de-essing, or taming a single bass note that pokes out of the mix more than others due to a room resonance.

Best regards,
Steve Berson

Angie
01-23-2005, 08:57 AM
I've been using multiband compression on wire recording transfers. EQing had worked ok. Multiband compression smooths things out much better. Again, a "fix" situation. I seldom think of using it when it's my own work.

Cary B. Cornett
01-23-2005, 12:44 PM
I guess I worded my original post poorly, since the return comments are all about multiband compression. Although these are good commments, they don't address my main question. I only used the multiband compression as an EXAMPLE of one possibility among many.

My concern was about processing latency of different plugin API's and how each "model" deals with that latency, a matter of comparison among SAW native, DX, and VST.

I am also curious about whether I can use the JMS send/return to enable parallel processing.

Cary B. Cornett
Cornett Technical Services

AudioAstronomer
01-23-2005, 12:48 PM
I guess I worded my original post poorly, since the return comments are all about multiband compression. Although these are good commments, they don't address my main question. I only used the multiband compression as an EXAMPLE of one possibility among many.

My concern was about processing latency of different plugin API's and how each "model" deals with that latency, a matter of comparison among SAW native, DX, and VST.

I am also curious about whether I can use the JMS send/return to enable parallel processing.

Cary B. Cornett
Cornett Technical Services
I answered that in the second post I beleive.

Cary B. Cornett
01-23-2005, 06:19 PM
I answered that in the second post I beleive.

You mentioned the Latency Compensator, which I have (and use with SIR, for example), but not the JMS Send/Return gizmo, which is what I was asking how to use for parallel processing (sometimes mis-called "sidechain" because it involves setting up a parallel signal chain "off to the side" for the effect, usually a compressor, which can then be blended with the un-processed sound from the other chain).

Cary B. Cornett
Cornett Technical Services

AudioAstronomer
01-23-2005, 06:51 PM
Ah.

Normally I just duplicate the track. Either way You end up using another track, by duplicating the regions you can edit/automate much easier IMO.

Yura
01-23-2005, 07:04 PM
You mentioned the Latency Compensator, which I have (and use with SIR, for example), but not the JMS Send/Return gizmo, which is what I was asking how to use for parallel processing (sometimes mis-called "sidechain" because it involves setting up a parallel signal chain "off to the side" for the effect, usually a compressor, which can then be blended with the un-processed sound from the other chain).

Cary B. Cornett
Cornett Technical Services

OK, with JMS send-return we can furcate the signal from one track to several tracks... say to 3... then we can patch our plugs on those 3 tracks for parallel processing, then mix them together some way...
But again, if we patch vst that introduces the latency, we cannot avoid the latency anyway without compensation...
If you need the real powerfull parallel processing (inside one track), I reccomend the Quantum FX plug (vst and dx here) or/& Reaktor. I use them instead of most heap of stuff and pervertions inside tracks paths for those purposes.

Bob L
01-23-2005, 11:05 PM
The built-in compressor/gates can be keyed from any other channel of the console... very easy to setup using the Key controls... pick another track to key from... the sidechain connection is made internally... the key can come from any track before or after the compressor being controlled... don't miss out on the eq filters in the key routine for turning the built-ins into very specific bandpass de-essers and other types of band limited effects.

The Levelizer can do the same and adds some interesting eaxtra features with the use of the Send A or B functions... multiple tracks can send data to the internal A or B buffer and then another Levelizer can key from that buffer... which feeds the mix blend of all the tracks sending to that buffer.

Bob L

Carl G.
01-25-2005, 03:50 AM
The compressor apparently introduced a difference in latency that caused some phase cancellations in the output sound. The "cure" was to insert another multiband compressor in output 1 that was set to do no processing (not "bypassed", though).
Cary B. Cornett
Cornett Technical Services / Chinese Puzzle Recording
Cary,
If you use the DX version of the compressor, doesn't that solve the latency issue?
(I have both the DX and VST versions.... and was guided by this forum to always use the DX versions if possible).
The reason I ask, is that it would be nice to know if when using the ol' Ultrafunk multiband (without the limiter function) there is still a latency issue in DX version that I wasn't aware of. (unrelated..... I also rarely use MB compression... but when you need it...it's a must have).

Cary B. Cornett
01-25-2005, 08:52 AM
The built-in compressor/gates can be keyed from any other channel of the console... very easy to setup using the Key controls... pick another track to key from...

Bob L

The features you describe are really cool, but not what I was actually talking aobut. I am taking the same signal through two different paths, one "straight" and one heavily compressed (could be multiband, Levelizer, whatever), which allows beefing up a track while leaving the original transients untouched. Some folk call this "sidechain compression" which is actually a misnomer, and probably why your answer, though good, didn't fit my question. Perhaps "parallel compression" would be a better term, but I don't see it in general use.

Cary B. Cornett
Cornett Technical Services

Naturally Digital
01-25-2005, 12:13 PM
Perhaps "parallel compression" would be a better term, but I don't see it in general use.Bob Katz is helping to change that. AFAIK, parallel compression *is* the correct term. It has been a popular technique in classic music production circles. I think it is a great way to enhance a full mix. When you get it right, it really brings up the detail. I haven't done much MB parallel compression but now that I have the Sonoris MB (with L-R x/o's ;) ) I'm looking forward to having more options. Some companies are starting to implement parallel modes in their processors. The TC6000 and Weiss Compressor are two examples I believe. I usually set up parallel processes on the output tracks in SAWStudio for mastering projects.

Cary, you've been dealing with this for a while now. As Carl mentioned, can you try the DX versions?

Now, if I could only get around to trying Upward Expansion in SAWStudio, I could answer Dave L's question! ;)

Cary B. Cornett
01-25-2005, 12:38 PM
Cary,
If you use the DX version of the compressor, doesn't that solve the latency issue?


And here we get back to part of my original question. Are DirectX plugins automatically latency-compensated? If so, does that compensation work if the plugin is inserted in an output channel?

I first started preferring DX versions of plugins because of graphics update overhead issues in VST, not because of processing latency. When I DID experience the differential latency problem, I do not remember whether it was with DX or VST versions in use.

Bob L
01-25-2005, 12:47 PM
Sorry for the misunderstanding... then it seems like Robert has it correct... simply duplicate the regions of one track onto another and do your compression... the internal compressors and most other DX compressors will not add latency.

Even Nattive and DX compressors placed in output tracks are comprensated for by SAWStudio's engine. It is dependent on how the plug is written though... any plug can introduce zero samples as they withold data, but SAWStudio allows you to design the plug without having to do that.

Duplicating track data in SAWStudio is a simple feature and part of many different types of mix effects in my book of tricks. Who cares about terminology... simply duplicate data on numerous tracks and process it and mix it in any way you want into the final mix... an easy and powerful technique that does not need any special kind of new technology or name to be utilized.

Bob L

Cary B. Cornett
01-25-2005, 12:49 PM
OK, with JMS send-return we can furcate the signal from one track to several tracks... say to 3... then we can patch our plugs on those 3 tracks for parallel processing, then mix them together some way...


I wonder if it is workable to do something like putting in series

JMS Send
compressor
JMS Return

in one track insert, with the send and return modules both selected to "1".

Would this result in the compressor output being combined with the return mix? If so, this would be a powerful add-on tool...

Cary B. Cornett
Cornett Technical Services

Cary B. Cornett
01-25-2005, 01:21 PM
... simply duplicate the regions of one track onto another and do your compression... the internal compressors and most other DX compressors will not add latency.

Even Nattive and DX compressors placed in output tracks are comprensated for by SAWStudio's engine.

Duplicating track data in SAWStudio is a simple feature and part of many different types of mix effects in my book of tricks.

I have used that trick in mastering since back with SawPro. It is indeed useful, as long as you don't run out of tracks. I want to experiment with multiple uses of parallel processing within one mix, and for that I will likely NOT have enough tracks. The ability to parallel process within a SINGLE track would be a very powerful feature.

Cary B. Cornett
Cornett Technical Services

Dave Labrecque
01-25-2005, 01:52 PM
What was Dave L's question? :confused:

Naturally Digital
01-25-2005, 02:26 PM
What was Dave L's question? :confused:Oh Dave! So sorry! My memory isn't as good as I (arrogantly) thought it was. ;)

It was Carl that was asking...

How could I have done upward expansioin in SawStudio?
Ideas?
CarlIt's still on my to-do list BTW. Right after renewing my lease, getting a website up and submitting some tunes to SAWStudio Radio! :D

Carl G.
01-25-2005, 05:22 PM
I have used that trick in mastering since back with SawPro. It is indeed useful, as long as you don't run out of tracks. I want to experiment with multiple uses of parallel processing within one mix, and for that I will likely NOT have enough tracks. The ability to parallel process within a SINGLE track would be a very powerful feature.

Cary B. Cornett
Cornett Technical Services
Cary, I do parallel processing thru duplicate channels in SawStudio like mentioned here (kinda same way you'd feed a regular board anyway:) )
However... there are DX compressors with the MIX mode on them to achieve the same results also. (Just not on the compressors I personally prefer).
PSP Vintage Warmer
Sony (SF) Multi-Band Dymnamics

Yura
01-26-2005, 05:08 AM
I wonder if it is workable to do something like putting in series

JMS Send
compressor
JMS Return

in one track insert, with the send and return modules both selected to "1".

Would this result in the compressor output being combined with the return mix? If so, this would be a powerful add-on tool...

Cary B. Cornett
Cornett Technical Services

Not understood, really, why "putting in series" if you interested in parallel...



Can the JMS send/return plugin be used to facilitate parallel processing within a single channel or path, and if so, how?

Verdict: NO :)
There's no chance to go parallel ways inside one track... without using of a specific plug module (that I described below).

Cary B. Cornett
02-03-2005, 06:59 PM
Not understood, really, why "putting in series" if you interested in parallel...

Ok, the idea is to use the send and return to provide the "unprocessed" side path. If you put a send in an insert before, say, a compressor, the compressor still gets the same audio that goes into the send. If you could ALSO have a return AFTER the compressor, and the return provided a "pass through" for the effect output in the chain before it, you could indeed use the send and return "in series" with the compressor to provide a parallel path withing the same channel.

Verdict: NO :)
There's no chance to go parallel ways inside one track... without using of a specific plug module (that I described below).

I wrote JMS about this, an you are correct, although he found the idea I suggested intriguing. I am still waiting to hear if he tries to implement it.

Cary B. Cornett
Cornett Technical Services