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Hi All,

I am trying to work out how to use an external compressor or EQ with DP 5.01. I know how to get in and out by using an Aux send, etc, but I have not figured out how to deal with the latency. Specifically, I am concerned about the sample buffer latency as well as the AD/DA converter latency. Is there a way to get DP to handle this, like it does with plug-ins?

In general, is anyone doing this? Or is it more like once it's in the box, leave it in the box?

--Andy

auptown wrote:Specifically, I am concerned about the sample buffer latency as well as the AD/DA converter latency. Is there a way to get DP to handle this, like it does with plug-ins?

No. DP will not do this. Perhaps one day?
Sample buffer latency shouldn't matter in this case.
What will matter (slightly) is the couple of ms needed for both the AD and DA conversion.
Could be 3-6ms all up.
At any rate, the specific figures are immaterial.

auptown wrote:In general, is anyone doing this? Or is it more like once it's in the box, leave it in the box?

"In general", it's still a case of "each to his own".
Hey, if you like the sound of a particular piece of gear, why not?

I'd use an aux send or direct buss output to route the signal through your compressor whilst it is bypassed, and record the result.
Then play this along-side the original track, taking note of the offset.
This will be easier if you bypassed the compressor during the pass, as the waveforms sould now look very similar.

From then on, you can simply copy any audio you want to treat this way to an adjacent track, applying the offset to that track, muting the original and bussing it out to your compressor.

Hope this helps, auptown.

I think the easiest way to deal with this is to simply sum outside the box. You need a lot of high quality D/A, because instead of just sending the one track you want to use outboard on, you send them all out on individual outputs. You'll also need a console or a summing box.

auptown wrote:...I am trying to work out how to use an external compressor or EQ with DP 5.01.... I have not figured out how to deal with the latency...Specifically, I am concerned about the sample buffer latency as well as the AD/DA converter latency

Swiftness, I don't see any indication auptown is lookin' to make a purchase.
Converter delay and buffer latency are his concerns.

When I want to do this, I just shift the track ahead in time by the amount of latency (temporarily) to listen to the mix and adjust the outboard gear. Then when all is adjusted to my likings, I set the track back to its original time stamp and record the processed signal on an adjacent track. (Set Nudge Amount is your friend!)

Works for me.

Phil

Wow, this was my first post/question and it's great to get feedback and ideas about this. I get the basic idea, that I can manually account for the I/O latency and nudge the track.

But, I had thought for sure that the buffers latency would contribute to this -- I am running 1000 (1024?) buffers, which is significant at 44.1kHz. Am I understanding that this is not the case?

ADC only ITB. In the analog days we rerecorded tracks trough outboard gear and didn't even think that there could be something to compensate.

auptown wrote:But, I had thought for sure that the buffers latency would contribute to this -- I am running 1000 (1024?) buffers, which is significant at 44.1kHz. Am I understanding that this is not the case?

If you're monitoring while you record inside the program (ie. not using cuemix etc.) then you'll hear the delay induced by the latency, but that will be adjusted for by the program and the track will be put in the correct place when you play it back. So even with a huge buffer you'll still only have to account for the latency induced by the DA-AD converters and your FX itself. Possibly so small that you won't even have to worry about it.

Mr_Clifford wrote:If you're monitoring while you record inside the program (ie. not using cuemix etc.) then you'll hear the delay induced by the latency, but that will be adjusted for by the program and the track will be put in the correct place when you play it back. So even with a huge buffer you'll still only have to account for the latency induced by the DA-AD converters and your FX itself. Possibly so small that you won't even have to worry about it.

Thanks, Mr_Clifford; you beat me to it.
A simple way of looking at this is that DP always records audio exactly as and when it appears at its inputs.

OK, I think I've got it. Again, thanks for the great input. I'm impressed with the knowledge pool that is here!

I don't remember now whether it was something we just talked about, or if there is an actual plugin, but at one point there was discussion about a plugin that would measure the delay in an outboard return, then report to DP as though it was a regular plugin so as to generate ADC info. Anyone know if that was pie-in-the-sky or real?

If not, and if anyone is looking for a programming challenge that might pay off, well there's your baby.

Shooshie

I tried this with the plugin (I don‘t remember the name, but it was free), but didn‘t work... tried several different ways....

Ay! Uptown Girl wrote:OK, I think I've got it. Again, thanks for the great input.

Kewel, AyUptown!

Ay! Uptown Girl wrote:I'm impressed with the knowledge pool that is here!

Hey, we're impressed... and we live here!

Dr. Shooshie Shooshmeister wrote:I don't remember now whether it was something we just talked about, or if there is an actual plugin, but at one point there was discussion about a plugin that would measure the delay in an outboard return, then report to DP as though it was a regular plugin so as to generate ADC info. Anyone know if that was pie-in-the-sky or real?
If not, and if anyone is looking for a programming challenge that might pay off, well there's your baby.
Shooshie

Hey, Shoosh.
I love the way you think.

Eureka wrote:I tried this with the plugin (I don‘t remember the name, but it was free), but didn‘t work... tried several different ways....

Could it be "Expert Sleepers' Latency Fixer AU"?
I think they wrote it as "ExSlLatency Fixer AU" or something like that.
Tried that one, anyhow, and for whatever reason it's ended up in my "sus" plugs area.
I've just confirmed that I tried "ExSlLatency Fixer AU 1.0.0" in DP 4.1.

It's possible we both tested it in non-ADC versions of DP.
As you'll see below, this is critical, as the plug fools DP's ADC engine!

I dug this up from the v1.0.0 ReadMe...

How to use it

The plug-in reports to the host application that it has a latency (controlled by the plug-in parameters) but does not actually apply any processing to the audio signal. This causes the host to use its own latency compensation to advance the audio fed into the plug-in by the requested amount.

This is useful to compensate for e.g. routing audio via outboard effect processors, where the audio's journey out of your audio interface and back in to the computer introduces a latency into the signal. For example you may find it useful in conjunction with Logic's Helper->I/O plug-in.

For it to work, the host application must support 'plug-in delay compensation' and the feature must be turned on. Recent versions of Logic and Digital Performer support this feature, for example. (Preferences->Audio->General in Logic.)

In general applications will not respond to changes in the latency setting during playback. If you need to interactively set the latency, try setting this plug-in to a large setting and then using my Buffer Delay plug-in to experiment with different settings. Once you've found the correct values, subtract the Buffer Delay delay from the latency setting and remove the Buffer Delay plug-in.

Auptown, using this plug (assuming it works for you) would allow you to take any external path you like.
I know it sounds like nirvana, but you should be able to ignore any and all processing/ converting delays!
At least, that's the theory...

Oh, and there's a special caveat for (i)Logical users, also from the v1.0.0 ReadMe...

Unfortunately Logic 6 does not respond to changes of latency at all, even when playback is stopped. As a workaround, Latency Fixer remembers its last used settings and uses them as defaults when creating a new instance of the plug-in, which is the only time Logic 6 queries the latency. Logic 7 works properly, in that it responds to latency changes in the plug-in.

I think I'm done for now... Phew!
Hope something helps someone help someone hope!