Sync drift between ACID Pro 3 and Tape -ACID Product Family

Subject:Sync drift between ACID Pro 3 and Tape Posted by: MBET Date:1/1/2005 9:51:10 AM I searched the forum but can't find this problem exactly. Can someone help me out? The only thing I found was someone saying that ACID Pro 3 doesn't slave, it only triggers on/off to a MIDI Time Code signal presence/absence (but that sounds rediculous) First the problem then the detailed set-up: Problem: ACID Pro 3 and My tascam 38 will sync up but there is a noticable drift. NOT as subtle as "flanging" but not so noticable that I picked up on it right away. It could best be described as rushing and dragging the beat making playing bass along with the drums (in ACID) a frustrating experience) The Set-up: I created a drum track using ACID Pro 3 on my PC (Dell Pentium4/XP/M-Audio2496) and wanted to track bass guitar to my Tascam 38 while the computer synced to it. My plan was to leave the drums in ACID and just have the computer slave to the SMPTE code (via JLCooper PPS2 30FPS Non-drop, MTC to the midi in on the M-Audio). I striped track 8 with SMPTE from the PPS2 (30F/S Non-drop and VU meter was at 0). Then I sent the SMPTE to the PPS2 converting it to MTC. MTC via Midi in on the M-audio card, ACID set up to trigger to Midi TimeCode. When I played the tape, ACID started playing along and all seemed right in the world. I tracked bass to tape (playing along with the sync'd drum track) and it felt pretty good. When I listened back the groove between bass and drums felt good but not quite "in the pocket". It felt like I pushed and pulled a bit. So I tracked it again and listened back... Same thing. I kept redoing the bass part over and over until finally noticed one phrase that had felt perfect when I tracked it was really off on playback. So, I dumped the drumtrack to tape and tracked bass to tape without the computer involved and the groove was rock solid. SO MY QUESTION: I realise that MTC will allow flanging like drift but this was much worse than that. Has anyone experienced this before? What did I do wrong? Any hints/fixes?
Subject:RE: Sync drift between ACID Pro 3 and Tape Reply by: pwppch Date:1/1/2005 8:15:38 PM ACID does not slave to incomming MTC. It only triggers start. ACID wants to be the master. Since ACID will not slave to incomming MTC, you must set things up to use a common clock between your MTM and your sound card. If you are using a DA-38, which it doesn't sound like, then you should make sure that your audio card and the Tascam are using a common digital clock. If you are using the old 38 reel-to-reel, then there is no way to sync ACID to a common digital clock and drift is a likely result. Peter
Subject:RE: Sync drift between ACID Pro 3 and Tape Reply by: MBET Date:1/3/2005 5:04:19 AM Peter; Thanks for your response. I am in fact using a reel to reel (not a DA38) so I guess I won't be able to sync ACID to tape. ACID not being able to sync to an external MTC is a real weakness. Does Sonic Foundry/Sony have any plans to remedy the situation? Brian
Subject:RE: Sync drift between ACID Pro 3 and Tape Reply by: pwppch Date:1/3/2005 8:12:50 AM In order to achieve a true slave/sync, ACID would have to resample on the fly. This will effect the quality of the audio. We chose a trigger only mode based on the assumption that the master device would be a digital device and have common digitial clock capabilities. Yes, this is a broad assumption, but one that prevents us from going down the slippery slope of resampling the output of ACID on the fly to a non-sample accurate clocks source such as SMPTE/MTC. I will bring it up for discussion again. Peter

Subject:Sync drift between ACID Pro 3 and Tape

Posted by: MBET

Date:1/1/2005 9:51:10 AM

I searched the forum but can't find this problem exactly. Can someone help me out? The only thing I found was someone saying that ACID Pro 3 doesn't slave, it only triggers on/off to a MIDI Time Code signal presence/absence (but that sounds rediculous)

First the problem then the detailed set-up:
Problem: ACID Pro 3 and My tascam 38 will sync up but there is a noticable drift. NOT as subtle as "flanging" but not so noticable that I picked up on it right away. It could best be described as rushing and dragging the beat making playing bass along with the drums (in ACID) a frustrating experience)

The Set-up: I created a drum track using ACID Pro 3 on my PC (Dell Pentium4/XP/M-Audio2496) and wanted to track bass guitar to my Tascam 38 while the computer synced to it. My plan was to leave the drums in ACID and just have the computer slave to the SMPTE code (via JLCooper PPS2 30FPS Non-drop, MTC to the midi in on the M-Audio).

I striped track 8 with SMPTE from the PPS2 (30F/S Non-drop and VU meter was at 0). Then I sent the SMPTE to the PPS2 converting it to MTC. MTC via Midi in on the M-audio card, ACID set up to trigger to Midi TimeCode.

When I played the tape, ACID started playing along and all seemed right in the world. I tracked bass to tape (playing along with the sync'd drum track) and it felt pretty good. When I listened back the groove between bass and drums felt good but not quite "in the pocket". It felt like I pushed and pulled a bit. So I tracked it again and listened back... Same thing. I kept redoing the bass part over and over until finally noticed one phrase that had felt perfect when I tracked it was really off on playback. So, I dumped the drumtrack to tape and tracked bass to tape without the computer involved and the groove was rock solid.

SO MY QUESTION: I realise that MTC will allow flanging like drift but this was much worse than that. Has anyone experienced this before? What did I do wrong? Any hints/fixes?

Subject:RE: Sync drift between ACID Pro 3 and Tape

Reply by: pwppch

Date:1/1/2005 8:15:38 PM

ACID does not slave to incomming MTC. It only triggers start. ACID wants to be the master.

Since ACID will not slave to incomming MTC, you must set things up to use a common clock between your MTM and your sound card.

If you are using a DA-38, which it doesn't sound like, then you should make sure that your audio card and the Tascam are using a common digital clock. If you are using the old 38 reel-to-reel, then there is no way to sync ACID to a common digital clock and drift is a likely result.

Peter

Subject:RE: Sync drift between ACID Pro 3 and Tape

Reply by: MBET

Date:1/3/2005 5:04:19 AM

Peter;

Thanks for your response. I am in fact using a reel to reel (not a DA38) so I guess I won't be able to sync ACID to tape. ACID not being able to sync to an external MTC is a real weakness. Does Sonic Foundry/Sony have any plans to remedy the situation?

Brian

Subject:RE: Sync drift between ACID Pro 3 and Tape

Reply by: pwppch

Date:1/3/2005 8:12:50 AM

In order to achieve a true slave/sync, ACID would have to resample on the fly. This will effect the quality of the audio.

We chose a trigger only mode based on the assumption that the master device would be a digital device and have common digitial clock capabilities.

Yes, this is a broad assumption, but one that prevents us from going down the slippery slope of resampling the output of ACID on the fly to a non-sample accurate clocks source such as SMPTE/MTC.

I will bring it up for discussion again.

Peter