Hi all,
When I first used GB I was blown away by the recording quality - so clear and true.
Now, some six months later, I'm getting vibration and some distortion.
Can this be due to Mac updates?

I've also heard that if you have other audio programs on, e.g. Skype, this can affect recording, so I've closed Skype but that too seems to have marginal effect.

I've tried changing the settings but this doesn't seem to make the recordings (my voice and mp3 accompaniment) any better.

Can anyone help?

Here's a quick check:
Open an earlier project that you know is good. Output that project to MP3 and compare it with your previous MP3. If they sound the same, you don't have a problem with GB. If they are different you have a problem somewhere, but not necessarily in GB. You may have changed your setups. It would be helpful to hear what it is you're describing.

I don't know how Skype could infiltrate your tracks unless you have accepted Skype as a midi input. Also check your inputs, i.e., HDMI or FW or other USB devices. Go in and out of GB and see how many inputs turn on when the program first initializes. I don't know your setup but you should know how many inputs you should have.

Hope this helps and let us know what you find.

Thanks for your suggestions. I'm away for a few days, but I'll let you know the outcome.

[quote name='mikesum' date='Sat 30 Apr 2011, 09:06' post='319182']
[quote name='triads' post='319179' date='Sat 30 Apr 2011, 06:37'] Go in and out of GB and see how many inputs turn on when the program first initializes. I don't know your setup but you should know how many inputs you should have./quote]

Triads, not sure what you mean by that.
I did what you suggested concerning the two mp3 files and although as far as I can see, the settings are the same, there's definitely a big difference in the sound output.
The recordings I made a few months ago are completely free of any distortion. The red signals indicating unduly high recording levels, present in the 'noisy' recordings, are completely absent from these earlier recordings.

It's as though the later recordings lack some kind of filter. As soon as you key in R to record, this undesirable quality becomes apparent.

it would be good to know what hardware you're using. do you have an audio interface? or do you record your voice with the built in mic?
not to be very simple, but do you understand the concept of 'gain staging?' each of your input and output level controls must be set at a best level. that level must keep the signal moderated to avoid 'clipping', the red levels you're getting.
on the mac, and in GB, there are several places that takes place.
if you're using the built in mic, cx the audio midi settings for the input level.
a hardware interface will have knobs, and perhaps a virtual control panel.
GB itself has several level faders for output, track and master, as well as the option to 'normalize' the signal on bounce down. cx those as well. none of them should be too high. perhaps a good test would to be bring them all down and see what happens.
finally, perhaps something did creep into GB. short of wiping and reinstalling, at least trash the prefs for the program, located in your drive>library>preferences folder. just drag the com.apple.garageband prefs to the trash, empty the trash, and restart GB.
good luck. persist!

Before you do anything that involves deleting, re-installing, etc, shut down your computer and restart. Again yesterday, I upgraded to Firefox 4.01 and the audio after the installation was just awful (but OK with Safari). Restarting allowed all the settings to take effect and now Firefox is fine. The problem was that some of the drivers for some core programs were not compatible with Firefox 4. Mozilla found a path that worked but only a restart of the OS would allow the implementation to fully complete.

Another issue I found out the hard way is to uninstall drivers (if an uninstall program is available from the software vendor) before re-installing them. I had a problem with a Line 6 audio interface that could only be resolved by un-installing the drivers as a first step. We all have our share of trial and error but the main thing is to keep at it. Good luck!

Mikesum ... this sounds like your problem is with your input gain adjustment. You hit R and the levels go into the red .... that would be your input gain set too high. That said:

1 .. what I meant. When you initialize GB it tells you how many midi inputs are active. If it doesn't, turn your midi controller on/off or your DI on/off and a pop-up window will indicate how many midi inputs it detects. If you normally have 2 inputs and now you have 3 or 4, you may be interfacing with an unintended source. But if it's not on any track, it shouldn't be on your export.

2.. When you opened your earlier project file, the good one, nothing should have changed and I didn't want you to do anything to the project except export the sound. All original project settings should migrate (at least I think they should). Listen to the project and see if it sounds good. If it sounds good export the sound. It that exported sound file is not what you just listened to in GB, you have a problem and I have no idea what that is. If the exported sound is good, then GB is okay.

3.. My understanding is that when you now record your levels are high. Can you not adjust your gain? If you're using a DI your gain control should be on your DI, in fact the record gain is probably disabled at GB if you've selected the DI as your input pref. What ever ... my question is can you lower your gain?

4 .. in line with what HoustonMusic is asking, what do you use with GB, how is it connected, how are your prefs set? And what version GB are you using?

5. Tips: Mic recording is the most demanding because it's dynamic, always changing, each person/voice requiring their own setup. I never record over 0db. My highs are typically -9 db and my average would be in the teens, maybe -15 to -18 db. I rarely record higher than -9 db or lower than -29 db. Don't use the waveform as a measurement ... the best sounds barely produce a ripple. Use the compressor if necessary but leave all other effects off until you're ready for your track finals and then move on to your master. You really want to keep the initial recordings as dry as possible.

let us know what you find.

I just realised that the recording level button was set at 3/4 maximum on one recent recording.
Haven't had a chance yet to check and record other things but it looks like this might have been the problem.
I feel abashed, I must say, in the face of so much info.

Thanks to you all! If I experience more problems I'll be back...
Mike

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Triads, thanks for your great input on the workings of GB and MIC recording!! John N.

Thanks jnoe14 (see also my earlier post).
It looks like, for some reason, that when GB was initialised the recording level was being set at 3/4 maximum.
I'm pretty sure this wasn't the case some months ago.
I just use GB for voice and mp3 file accompaniment - a pretty simple arrangement, with no exterior connections. I find the built-in mike fine for my needs.