<subject header fixed by admin - pls use an appropriate tag as outlined in the msg footer below> Hi everyone! I am a first time logic user and have been spending the last few days getting used to the new environment. I just wanted to see if anyone else has had the issues I've encountered. Here is my setup: Powerbook G4 667 1 GB RAM Logic Audio Platinum 6.2.1 MOTU 896 with Firewire Driver 1.05 Emagic Unitor8 mkII I setup my K2500XS and JV-1080 to be connected to the Unitor. MIDI seems to work fine. The K2500XS is going into the AES/EBU ins on the 896, and the JV is going into analog 3.4. So far, so good. I create 4 audio input objects in Logic to monitor inputs 3,4,9,and 10, respectively. Audio comes through fine, but I notice a rather large latency problem that makes it very difficult to play. I press a key, and there is a delay before I actually hear anything. So then I notice that in the audio preferences panel, I had set the I/O buffer to be 2048, and I read on the web that reducing this value will reduce latency (as well as the number of audio tracks you can use simultaneously). So, I set it all the way down to 64, and now there is no detectable latency. Great! Or so I thought...now there are fairly frequent audio pops and clicks and general audio noise. I read stuff on the newsgroups talking about how to get rid of audio pops, turning velocity engine off, disabling Altivec, etc. and so I go ahead and set the processor type to "generic", as opposed to PowerPC Altivec. Still no luck. I finally decided to try messing with the I/O buffer value a little more, and it seems that when it's set at 128, the pops and clicks go away, and there is only a very slight latency when monitoring. If in fact the pops and clicks stay gone, I can live with the slight latency. BUT, I guess the big question out of all this is: has anyone else seen this apparent trade-off between latency and audio noise in the I/O buffer parameter? Or perhaps I've missed the boat on this. Is there any way to minimize latency and still use software monitoring cleanly? What is it that causes these audio pops anyway? Any insight would be greatly appreciated. Thanks a lot! -Greg

--- In logic-users@yahoogroups.com, "chune11" <gregory_chun@s...> wrote: > messing with the I/O buffer value a little more, and it seems that > when it's set at 128, > the pops and clicks go away, and there is only a very slight latency > when monitoring. This is also my experience when running multiple live inputs (usually all 18, would use more if I had them) alongside softsynths and midi - 64 samples is usually unusable, 128 is usually rock solid, whether OS9 or OSX. If I lose the softsynths or the multiple live inputs then 64 is generally usable, though my experience with VSTis in OS 9 was that some softsynths just don't much like a 64 sample buffer anyway. You can reduce your latency using a 128 sample buffer by running at a higher sample rate, though the processor/disk requirements of running at 88.2 or 96kHz will likely far outweigh the fairly slim benefits of the halved latency. RME Hammerfall DSP Multiface, Powerbook G4 1GHz, OS X 10.2.5 John Pitcairn

On 9/5/03 2:38 PM, "chune11" <gregory_chun@...> wrote: > BUT, I guess the big question out of all this is: has anyone else seen this > apparent trade-off between latency and audio noise in the I/O buffer > parameter? Or perhaps I've missed the boat on this. Is there any way to > minimize latency and still use software monitoring cleanly? What is it that > causes these audio pops anyway? > > Any insight would be greatly appreciated. Thanks a lot! > > -Greg welcome to the Buffer Game :) this is common to all current DAWs as far as I know and actually has more to do with your audio interface and how its drivers interact with both CoreAudio and your DAW. to my knowledge a truly "latency-free" interface does not exist though some manufacturers have come up with clever marketing phrases that would indicate otherwise. For example your MOTU 896 does feature near-zero latency monitoring for any 2 inputs. in order to achieve this the 896 driver flows the audio coming in to the 2 selected inputs and pumps them directly out of the interface vs. going through the computer for processing. If you have the latest 896 driver you should have the MOTU Console application that allows you to select which 2 inputs you want to monitor "latency-free". For a lot of applications this is an acceptable compromise. However this doesn't solve the latency issue if you're trying to record on more than 2 inputs simultaneously, e.g., if you were recording a band or if you were mic'ing drums, OR a situation where you want to hear what you're recording through any effects/processing done within Logic. In these situations you would resort to the buffer game, which at its simplest level works something like this: * when recording, set your buffers as low as possible and disable any non-essential tracks. I personally find a setting of 256 acceptable for most MIDI stuff. Drums/percussion I'll go down to 128. * when NOT recording bump your buffers up to 512 or 1024. when mixing you may want to go higher as a higher buffer setting tends to = more plugin count. hope that helps! regards, brian