Hey guys,
I wanted to get a professional opinion on my recording level. I have the recording volume in Audacity set all the way down (raising it all the way up doesn’t appear to make much of a difference on the graph) and the volume on the mixer is set to about a medium level I think. (not at the auditorium so I don’t remember exactly)
You can see the levels in the pictures I attached, I have been amplifying it because it is definitely low when I play it back. I guess a sound sample would have been a better idea then the images but I didn’t think of that at the time and it is to late to do it tonight, I can upload sound samples tomorrow/later today as it is.
Thanks!
(it seems to be showing the images backwards with the first image I uploaded on the bottom)
[moderator note] I’ve reversed the order of the images using the “place inline” button
The recording level looks fine - the peaks in the loud part are at about -6 dB (0.5 on the linear scale) which is ideal. However, the tops of the peaks look flat, which indicates that the sound is being clipped/distorted before it gets to Audacity.
If you give full details of the equipment used and how it is all set up we may be able to suggest why that may be occurring.
If you apply the amplify effect with the default options it will amplify the sound so that the new peak will be 0dB, this is the maximum you should have, above that you get distortion. Some people prefer to be a bit more conservative (like me) and amplify to a new peak slightly below 0dB (usually somewhere between -2dB and -0.3dB).
The levels in the first image look perfect, except for the flat tops which suggests clipping prior to audacity recording, as Steve suggested. Without knowing which equipment you used and how you have it connected we can’t say how you can solve that.
The recording level on the second image look a bit too low.
If your recording has a lot of dynamics (some parts sounding quite loud and other parts sounding very quiet) and you want to narrow the volume differences between quiet and loud parts then you need to use dynamic compression. If you search the forum for dynamic compression you’ll find a lot of threads about it.
It is generally thought best practice to apply DC offset correction as the first thing you do immediately after capture - apply no amplification at that stage. You onlt need to do this if your signal is carrrying some DC - you can see this when the waveform is off-centre from the zero line.
Normalization or Amplification is normall6y the last editing step after all other editing, i.e just prior to exporting your production audio files. Amplify and Normalize in Audacity both do similar, but subtly different things. Amplify works on both channels of a stereo signal equally whereas Normalize works on each of the two channels separately. So Normalize is good if you have unbalanced equipment in your recording chain - otherwise it is better to use Ampliffy so that you do not change or damage the stereo image.
the advice not to amplify/normalize up to odB is good - although this is the theoretical maximum peak loudness to avoid clippin some audio players do not like playing audio files with 0dB peaks. ltuuredic recommends -1dB, I am a bit more conservative peaking at -2.0db (but even than my son complains that my recordings are too loud on his iPod - so-2.0 dB should be plenty loud enough ).
Hmm, yea the peaks are a little flat. The loud part was a video being played on another laptop going through the mixer, more details below.
Is this the dynamic compression you are talking about? http://pdf23ds.net/software/dynamic-compressor/
The softer part in the second image is our pastor speaking, I guess I should raise his recording volume to match up closer to the video. I think the reason I have him down is because occasionally he accidentally blows on his wireless mic or saliva hits it or something and it makes a loud sound. It’s hard to explain but I could easily find a clip of it if you wanted to hear.
Maybe I should explain a little about what I am doing before I start describing the equipment so I don’t come off as being rich, or being rich before starting all this, lol.
I volunteer at my church as the soundboard operator and do pretty much everything related to it. So this equipment is not mine except for the laptop I’m using to record but I can change anything I need/want to.
The mixer is a Yamaha MG32/14FX, I don’t recall what the amps are but I figure that is unimportant for this, I can get the information next Sunday if it would be helpful though.
We have multiple mics and instruments on stage totaling 4 plus on average.
For videos we run the output (from headphone jack) from our laptop controlling the overhead into Channel 18 Input B on the mixer. (The loud part shown in the first image is from here)
We have a wireless mic for our pastor but I do not remember the make or model of it, I know I was unable to find a manual online for it from the manufacturer. It is on Channel 23 Input A on the mixer.(The softer part in the second image is from here)
Aux 1 and 2 are monitors on stage and I am using Aux 3 for recording, it is mono so I am mixing everything down to one channel and sending it to the recording laptop through it’s microphone port configured as line in.
I plan to make a desktop with 4-6 sound cards configured with JACK and the el cheapo mod and record each instrument and mic on a separate channel but I have to find the right parts first.
Well I think that’s everything, if I forgot something or you want to know something else just say so and I will give whatever information I can.
It is generally thought best practice to apply DC offset correction as the first thing you do immediately after capture - apply no amplification at that stage. You onlt need to do this if your signal is carrrying some DC - you can see this when the waveform is off-centre from the zero line.
Normalization or Amplification is normall6y the last editing step after all other editing, i.e just prior to exporting your production audio files. Amplify and Normalize in Audacity both do similar, but subtly different things. Amplify works on both channels of a stereo signal equally whereas Normalize works on each of the two channels separately. So Normalize is good if you have unbalanced equipment in your recording chain - otherwise it is better to use Ampliffy so that you do not change or damage the stereo image.
the advice not to amplify/normalize up to odB is good - although this is the theoretical maximum peak loudness to avoid clippin some audio players do not like playing audio files with 0dB peaks. ltuuredic recommends -1dB, I am a bit more conservative peaking at -2.0db (but even than my son complains that my recordings are too loud on his iPod - so-2.0 dB should be plenty loud enough ).
Thanks for the advice about the difference between normalization and amplify.
It is logical to distort stereo images, I don t thinking about.
I have very little experience, I ripped three LP.
Peaks’d left at 1 db because I love to listen to loud (100 watts RMS), so the amplifier would fall in clliping.
If you have more useful tips for ripps prayed for them.
Should be -1dB and not +1dB. Anything positive (above 0dB) will cause clipping.
Depends on what kind of problem your getting. Popfilter will mostly protect from the “pops” you get on the P’s. If the problem is on the SSS’s look at Trebor’s advice.
Well, this Sunday the wall wart for the wireless mic receiver got bumped so it was off, unfortunately this wasn’t found till after our pastor started speaking and we got him using a wired mic because we couldn’t figure out the problem.(We usually can’t see the wireless receiver because the recording laptop blocks it) Surprisingly his voice got picked up by one of the mics on stage even though there wasn’t one near him so I have what he was saying but it is faint and I have to turn the gain way up and then I get alot of noise. Can someone advise a way for me to amplify him and remove some of the noise? It doesn’t have to be perfect but I need to be able to hear more of him then the noise.
Here is a copy of the faint track with where we got him using a mic at the end.
I also lowered the master Aux 3 volume which was set to 8 or the 3 O clock position and raised it on a per channel basis.
Here is a copy of the soundboard manual if you want to look over the board.
Here is all the information I could get off the wireless mic receiver, maybe one of you guys would know where to find a pdf of the manual.
galaxy audio
any spot
as-msmoor
uhf receiver
I noticed I didn’t post my Audacity version or what OS I am using so I will do that now.
Audacity 1.2.6
Recording PC: Windows Vista
Editing PC: Windows XP SP2
The recommended version for Vista is 1.3.12 (and pretty much for all other OS’s too), it has more features and is actually more stable in most recent OS’s.
Ok, I ditched the junk and did some work with Compression, Amplify, and Normalize and then put a short fade-in(15 seconds or less) on the beginning.
I was going to attach a sample to this post but the forum keeps throwing errors, last night I think it was saying the attachment filesize limit was 2MB tonight it said 1MiB then once I got my sample down to 1 MiB it said “the board attachment quota has been reached” so I have uploaded it elsewhere and here is a link if you would like to hear what I have now.
Ok, I guess I should convert over to that. I have had 1.3.12-beta installed for a while but haven’t been using it, is that still the current version or is it out of beta now?
Yes that’s still the current one, though 1.3.13 (beta) is likely to be released soon.
The 1.3.x series are all classed as “beta” (even though they are now more stable than the old 1.2.6 version for most users). The next version to be released without the “beta” tag will be 2.0.
If you don’t want to be an “early adopter” of 1.3.13, just keep an eye on the forum - the regulars will start recommending it when they’ve had chance to check it out thoroughly, but for now 1.3.12 is the one to go for.
I think you’ve salvaged all of the usable material. Shame about loosing the start, but that’s the proverbial “spilt milk”.
I’ve applied all my magic tricks, (before-after here), but cleaning the lowest level audio does not reveal words which could not be understood in the original hissy audio.
Thanks for the effort Trebor. There were no words that couldn’t be heard in the original recording after raising the volume. I was just wondering if it could be amplified and cleaned some. I think I will just use the recording without the beginning though.
I’m not very literate when it comes to recording but have been using audactiy for a while now to record dialog for webinars and websites. This discussion on setting levels has been most helpful. Now I’m a better educated newb to this type of technology.
).
