PDA

View Full Version : Question of recording guitar using Garageband




williamh
Sep 25, 2006, 01:03 AM
I was directly plug my guitar into my macbook pro for recording. However, when I use Garageband's guitar amp simulation plug in, it somehow sounds a bit lag when I play. Is it normal? or I have to buy the cable that is designed to do the job?



PCMacUser
Sep 25, 2006, 05:20 AM
I was directly plug my guitar into my macbook pro for recording. However, when I use Garageband's guitar amp simulation plug in, it somehow sounds a bit lag when I play. Is it normal? or I have to buy the cable that is designed to do the job?
Hi there. If I understand your English, I'm guessing that the lag is due to the speed of the Macbook Pro. It may not be fast enough to process the amp simulation plug in in real time.

bartelby
Sep 25, 2006, 05:21 AM
Record the guitar dry and apply the effects after.

williamh
Sep 25, 2006, 07:13 PM
Hi there. If I understand your English, I'm guessing that the lag is due to the speed of the Macbook Pro. It may not be fast enough to process the amp simulation plug in in real time.

it's a macbook pro 2.16Ghz with 1gig of ram, is it still to slow for that?

zimv20
Sep 25, 2006, 07:37 PM
what you're hearing is latency. the signal you're hearing has to go through an analog to digital stage, be processed by the software, and then be rerouted back through a digital to analog stage so you can hear it.

the 1st and 3rd stages are not instantaneous and, for a particular setup, those values are fixed. the software stage can be made longer by adding plugs at record time.

so while a faster machine may help with the middle bit, you're still going to get latency. as recommended, you should record without plugs to minimize the latency, but you won't eliminate it so long as you're monitoring as you are.

there are other options, such as monitoring your analog signal before it hits the converters. there are a number of ways of doing that, the most basic being a y-cable, and the rest being further implementations of a y-cable (half-normal patch bay, split through a mixer, etc.).

williamh
Sep 26, 2006, 03:37 AM
what you're hearing is latency. the signal you're hearing has to go through an analog to digital stage, be processed by the software, and then be rerouted back through a digital to analog stage so you can hear it.

the 1st and 3rd stages are not instantaneous and, for a particular setup, those values are fixed. the software stage can be made longer by adding plugs at record time.

so while a faster machine may help with the middle bit, you're still going to get latency. as recommended, you should record without plugs to minimize the latency, but you won't eliminate it so long as you're monitoring as you are.

there are other options, such as monitoring your analog signal before it hits the converters. there are a number of ways of doing that, the most basic being a y-cable, and the rest being further implementations of a y-cable (half-normal patch bay, split through a mixer, etc.).

thanx for your reply, it's very informative!!

If I get an audio interface (say Motu Ultralite), problem will solve right?
That will address to another question, which audio interface works the best with Mac and Logic?

scottlinux
Sep 26, 2006, 11:17 AM
That will address to another question, which audio interface works the best with Mac and Logic?

Many. M-audio, Alesis, Pro-Tools hardware, Edirol, MOTU.... all the major companies' hardware works fabulously with Logic. I would recommend Firewire over USB. USB sends data in bursts, while Firewire is a consistant stream. This doesn't matter much for 16bit stereo, but for 24bit/96k and more than 2 channels, you really need firewire.

zimv20
Sep 26, 2006, 11:22 AM
If I get an audio interface (say Motu Ultralite), problem will solve right?
it depends on how you define the problem.

there are three ways to monitor:
1. before your signal hits the converters
2. after it's made a roundtrip through the converters and software
3. through an interface that processes it before sending it to the computer

in 2., you will *always* have latency. no interface device will fix that, though some are worse than others. and as i said above, any additional processing you do in s/w will slow it down more.

a good number of interfaces implement 3., and it looks to me that the ultralite does as well. if you look at motu's blub on this page (http://www.motu.com/products/motuaudio/ultralite), they say:

virtually no monitoring latency
...which leads me to believe they've implemented a y-cord inside the device. but it must be doing some processing, otherwise it'd be "no latency".

fwiw, i run with some latency. PT has a s/w feature called "low latency monitoring", and it's low enough that most people i have here don't care.