I had a Steve Vai naked track recorded into Logic 11 Pro and I was laying guitar tracks/takes down over the backing track with my QC and everything was working perfectly. Zero issues with recording or playing back guitar parts once I learned that you need to use input 3/4 instead of input 1/2 which is just a raw signal, but once that was sorted everything was perfect.
Recordings and Playback were flawless. I couldn’t believe how well it was all working.
This evening I was playing guitar with my QC and was jamming along with the logic tracks I have. I decided to re-record some new guitar lines over the already in-works project with Logic.
All of a sudden when I started the recording I got this nasty level of latecny. It was like an extra delay pedal had been put on the guitar. I couldn’t figure out what had changed. So I rebooted my MAC and my QC and tried it again. Still the same
If I disable monitoring on Logic and don’t output my GTR track to Stereo Outputs its slightly better, but bearly - and I know I never had to do this before.
When I play the track back it’s even worse. My recorded guitar part is lagging way behind the backing track. I tried both in Stereo and Mono and the result was the same.
This is obviously very disappointing, because I can no longer record tracks like this.
Would appreciate anyone’s help with this matter. It shouldn’t have just come out of nowhere, as it had been working perfectly with that exact same recording and setup before.
I really don’ think that’s an issue with QC, but with Logic. Just a few tips:
Ensure you have the smallest I/O buffer size on the audio settings
check what plugins/inserts you have on the guitar tracks, buses and on the output
The same thing has happened to me before, loading a previous project and suddenly there’s a huge latency… getting to find out I had forgotten to either reset the I/O buffer (I increase it when mixing), or leaving some plugins on (e.g limiters / multipressor ).
Of course, if you’re using a very CPU heavy preset on the QC, you may be finding latency issues on the QC itself… YMMV. I try to keep it simple when recording (just a simple compressor/boost/amp/cab lane and a DI lane, and getting around 1.7ms of latency)
Thank you. Yes, I found the problem eventually last night. It was indeed with Logic and not the QC. I had to enable the low latency mode. But what is most strange is that I never disabled it earlier, so not really sure what was going on there. However, as soon as that was enabled in the settings options everything worked as it did before, which is great. Nothing worse than bad latency preventing you from being able to record etc.
I didn’t have to tweak any of the other settings at all.
I know my current recording setting on Logic allows for about 5.7ms of latency, but wow - that’s great that you have yours down to 1.7ms. Maybe i’ll reduce buffers a bit more and see how that works going forward.
Just to make it clear, when I mention 1.7ms is the latency on the QC itself (80 samples from input to output - 1.66ms@48khz). The full latency is about 5.7ms also according to logic - I’m not sure how accurate that actualy is.
I’ve found that the Low-Latency mode setting doesn’t always persist between projects or opening previous files. Sometimes you just randomly have to re-enable it. I put it on my taskbar/menu for a quicker find.
I find there are very few AUs CPU-intensive enough to knock me out of that mode, so I just leave it on all the time. Amplitube used to kill it but that’s the only one I can remember not cooperating
I had the same issue until i read on the forum to go into project setting and change the sample rate of project from 44.1khz to 48khz to match the QC. After this I had no Logic Pro latency issues.
You are right, and I did a little more digging into it to see if I could find anything. I tweaked my Samples to be lower, and it seems that if you play around with the Sample sizes and settings, the low-latency mode switches off automatically which is a bit of a pain.
So, in the end I put the samples back to where they were and just enabled LL mode again manually. Everything is working perfectlly with this setup, so I guess there is no need to be tweaking anytyhing. But thought I would just mention it and leave it here in case anyone else runs into similar issues.
Good idea to have it as a shortcut on your menu etc.
This is actually a very interesting point you make and has reminded me about another thing I wanted to investigate. In my haste to get stuck into recordings and playing the guitar, (Once I got the latency issue sorted again) I was enjoying recording tracks from my QC. However, I never stopped to change the sampling rate of the Audio Files.
So, essentially I am recording a 48KHz source into a 44.1KHz destination. Now I am not 100% sure what effect this will have, but common sense suggests this is NOT the best thing to do. The recordings sound fine though, but I would definitely like to have the sample rate match, interesting to know that this also helped you with latency issues.
The other thing I have thought about because I see people on YouTube mentioning it, is that the QC should be set to 100% volume to get all the nuances out of the unit etc. I can see why someone would suggest this, but I can’t see it having any effect on a USB based signal
I don’t know for sure because I’ve never checked it, but have seen others report that Logic can automatically match/convert sample rates. I thought it was only when you imported audio files to a project that it makes an actual conversion, but I’m not sure how that relates to a mismatch between QC and Logic.
Some users have reported they have no trouble with the mismatch.
I changed my template in Logic over to 48k just to be sure.
The main Vol wheel doesn’t affect the USB level according to my tests.
The only thing the wheel does is attenuate the audio volume level from the chosen physical outputs so it really doesn’t affect the digital signal content. Any difference people are hearing between levels are almost certainly the psycho-acoustic effects caused by the Fletcher-Munson curve (frequencies being perceived differently at different volumes)
