Alternative to automatic delay compensation?

audiobrad · Post by **audiobrad** » Thu Dec 01, 2005 8:20 pm

I have a second Mac running Kontakt in standalone mode. There is about 20 ms of response lag (latency) on the samples.

Is there an easy way to delay the MIDI tracks that play from the main DP Mac so that they are in sync with the 2nd Mac? (I know I can shift the tracks, or put a MIDI delay on each track, but these are cumbersome solutions).

It seems like there should be a feature where you can manually offset selected tracks by a fixed amount.

Any ideas?

Brad

studiodog · Post by **studiodog** » Thu Dec 01, 2005 8:40 pm

Why not select the MIDI tracks being sent to the second Mac and shift them ahead in time? If the majority of your tracks are NOT being sent to the second Mac then this would be less work than shifting all the rest.

audiobrad · Post by **audiobrad** » Thu Dec 01, 2005 9:15 pm

Well, it's film scoring and there's about 40 tracks in each. The problem with track shifting is that moving things off the barlines and beats makes editing harder. Waiting until your editing is done (before shifting them) means you have to suffer with the latency while your composing.

studiodog · Post by **studiodog** » Thu Dec 01, 2005 9:27 pm

Are your hardware MIDI devices going into a hardware mixer? If so, you could route a mix thru a digital delay to compensate.

audiobrad · Post by **audiobrad** » Fri Dec 02, 2005 9:54 am

Thanks Studiodog. It's an option. But it's hard to play the parts with the delay on (although the Kontakt stuff is already that way). I suppose it could be switched on and off. I guess these are all viable work arounds - but I kind of hoped someone might know of an obscure feature that handles this.

I wonder if my situation is all that unique????

Thanks for the input.

Brad

emulatorloo · Post by **emulatorloo** » Sat Dec 03, 2005 2:17 pm

audiobrad wrote:obscure feature

How is the latency set in Kontact on your standalone Kontact machine? Can you dink w it in the Kontact prefs? I am running a standalone EmulatorX machine MIDI'd to my G4 DP machine, and I have set latency real darn low in EmulatorX. . .am not noticing a delay.

audiobrad · Post by **audiobrad** » Sat Dec 03, 2005 3:16 pm

The output latency is now set to 18 ms. We had it at 8 ms, but as we added instruments, we had to increase it because the audio would start to break up.

Here's the interesting part:
It seems that the quantity of instruments - not their use - is what causes the break up. In other words, we were fine at 8 ms, then we added 8 new instruments, but they are not being played in the problem sections. To test this, I chose a 16 bar section that was experiencing audio breakup at 8 ms and deleted every unused instrument in that section and the problem went away! CPU and DFD seem to be in good control - experimenting with the DFD and buffer settings had no effect.

Another interesting tidbit - I can cut the latency approximately in half by going into the network MIDI function (we're using MIDI over ethernet in Tiger) and plug in an arbitrary negative latency number (I'm using -100 ms) and it improves it. Odd, I can reduce the latency with this network MIDI offset without breakup, but can't do it in the output latency slider.

The functioning of these two latency controls make no sense to me at all. Anyone?

(2) G5 2x2, 4.5 GB ram, Tiger, core audio, DP 4.6x, Kontakt, EWQLSO Gold Pro

Spikey Horse · Post by **Spikey Horse** » Sat Dec 03, 2005 5:17 pm

No helpful advice here.

Just wanted to say Studiodog, I love your new xmas makeover

studiodog · Post by **studiodog** » Sat Dec 03, 2005 5:33 pm

Spikey Horse wrote:No helpful advice here.

Just wanted to say Studiodog, I love your new xmas makeover

The awesome power of Thanksgiving leftovers can achieve many things...

Like, Be still a minute and don't shake your head!!!

Tim · Post by **Tim** » Sat Dec 03, 2005 7:57 pm

audiobrad wrote:The problem with track shifting is that moving things off the barlines and beats makes editing harder.

If shifting a track with a Time Shift MIDI Plug In, you won't have that problem.
Also, the MIDI plug in can be set for real time so tempo changes won't affect it (as it would with beats/ticks). Of course when shifting tracks earlier, make sure there's an empty bar up front.
A MIDI plugin can be command-option-dragged into a clipping window and then dragged into tracks where it's needed. Name them for specific (pre)delays and/or instruments.

audiobrad · Post by **audiobrad** » Sun Dec 04, 2005 12:42 am

Good tip. Thanks!

Anyone understand the latency settings for the audio output and Network MIDI setup?

nicken · Post by **nicken** » Tue Dec 06, 2005 3:48 pm

I did some tests tonight with the network MIDI setup. Interesting to say the least. I have two 1.6 ghz G5:s and one of them runs DP and the other one i use for Kontakt and other software synths. The computers are network connected.
Tonight i tried to send some MIDI notes over the network to the kontakt computer and then recorded the audio comming out from that computer to the dp-computer. Latency in kontakt was set to 40 ms and sure the recorded audio was about 40 ms after the MIDI notes when comparing the recorded audio data to the miditrack. Well here comes the interesting part. I had set up the MIDI network session on the Kontakt computer and after recording the MIDI data the first time i tried to lower the latency setting in the MIDI network setup to minus 60 ms. When i tried to record again the audio data was recorded "ahead" of the MIDI data in DP, if you understand what i mean. I did some testing and it turned out that when setting the latency in the network MIDI setup to -48 ms the audio lined up perfectly with the MIDI signal in dp.
I also tried to lower the Kontakt latency to 20 ms and with a latencysetting of about -28 ms in the MIDI network setup the audio data again lined up with the MIDI signal.
As i understand this my Kontakt computer must communicate with my dp computer requesting the MIDI data before it is actually played in DP. Could this be the case or am i missing something obvious? I‘ve tried to look for information on this on the net but i haven‘t found anything...
Any input would be highly appreciated.

Nicken

acro · Post by **acro** » Tue Dec 06, 2005 5:56 pm

Well in this case the Kontakt machine reports to the DP machine in advance that Kontakt needs data so many ms ahead of realtime. Subsequently, DP sends the MIDI data ahead of time during playback.

I find the title of this thread rather amusing... the discussion is 100% automatic delay compensation territory!

audiobrad · Post by **audiobrad** » Tue Dec 06, 2005 10:34 pm

Amazing! I will go through the same exercise myself. The only tests I ran were with the "live" keyboard controller and just feeling the latency. I wouldn't have thought the connection sophisticated enough to actually make the automatic delay compensation extend beyond the host computer. Wow!

I'm guessing however that the other MIDI tracks are actually being delayed rather than the network tracks being sent early. I read that somewhere in regards to automatic delay compensation.

Thanks Nicken - you really moved this discussion a huge leap forward!

Brad

croyal · Post by **croyal** » Wed Dec 07, 2005 5:43 am

This may seem strange but,

You can use a 3rd Mac to send sync to both your main two macs at once. That way both rigs will get the same delay from triggering. Also use an analog mixer to sum it all as the delay will be cut down instead of routing everything into one machine.

Has worked for us in the past. Of course you can substitute any other MIDI master device as you see fit.

Chris