recording itunes radio remove high pitch tone

hi, i have no idea about these things. definitely not an engineer. a friend told me i could record itunes, thus i’m using audacity. using windows xp, sigma tel cmajor audio card. can record itunes radio but annoying high hiss. please, will someone tell me step by step how can i remove it, what numerical values do i need to input?


One of the problems with the generic forums down here is that we have to start asking you stuff…like which Audacity do you have? Are you using a software package like Total Recorder to record shows, or did you follow the process to record Mix-Out or What-U-Hear?

Have you ever used the Noise Reduction tools?


using audacity 1.2.6
record what you hear(which is stereo mix? in windows xp)

i’m puzzled because i do not hear the level of high pitch noise coming from my speakers as i hear in the recording.

the noise reduction tools have numerical values that i cannot fathom which to select as i’m not a sound engineer

The noise reduction tools in Audacity 1.2 are value-free. To get any sort of good, stable, useful tools, you should install Audacity 1.3. You can install both Audacity 1.2 and 1.3 as long as you only launch and use one at a time. Audacity 1.2 projects will open up in both versions. Audacity 1.3 projects will only open up in 1.3

Write back when you get that far.


downloaded 1.3.7

two error messages

failed to start wxbase28u_vc_custom.dll was not found

could not delete c:docume~1ownerlocals~1tempaudacity.exe

Did you by any chance try to install 1.3 while 1.2 was still running? That would create all kinds of problems.


i just deleted 1.2
installed 1.3.7

could you tell step by step how can i remove the high pitch noise i mentioned in my first post? what function should i use and what numerical values do i need to input?

thanks for your time and patience!

Have you got Audacity 1.3.7 working now?

If so, to use the Noise Removal effect, you first need to tell it what kind of noise to remove - Fortunately this is easy to do because the Noise Removal effect just needs to “hear” the noise (on its own) and then it knows what it is supposed to remove.

Find a part of your recording that has no music, no talking, no other sounds, just the noise (preferably a couple of seconds, but at least half a second of isolated noise). Select the “noise” and call up the Noise Removal effect from the Effects menu. Click on “Get Noise Profile”. The Noise Removal effect has now “heard” the noise and is ready to go.

Now select part of the track that has the music (try this out on a section first - you may need to tweak the settings for best results, so you don’t want to be waiting ages for it to process a long track).

Call up the Noise Removal effect again and enter these settings:
Noise Reduction: 18
Frequency Smoothing: 150
Attack Decay: 0.15

The last two settings you can probably leave at these values as they are about right for most kinds of material.

Making the Noise Reduction number bigger will remove more noise, but if it is too high you will start to get some unpleasant metallic ringing/bubbling kind of sounds (artefacts).

If the noise is still too high, try increasing the Noise Reduction amount.
If the metallic artefacts are too noticeable, reduce the Noise Reduction amount.
Ideally you should aim for as low a number as will remove sufficient noise.

The noise reduction effect is a useful rescue tool, but if you always need to use it, it indicates that there is a problem somewhere. If you are recording on a laptop, try running from batteries with the power supply disconnected while you record (PC laptop power supplies are notorious for causing interference),
If that does not fix it, then I would suspect the sound card - on-board sound cards in PCs are usually pretty low quality. Fortunately upgrading a bad sound card to something considerably better can be done quite cheaply. One of the least expensive upgrades is the Behringer UCA 202, (I have one and I’m very happy with it).


who knew? i sure didn’t.

i think it’s the card. i unplugged the power supply and still couldn’t equalize the noise out

i was using the equalization option and saving it over my recording and received the following error:

an unhandled exception occured press abort retry ignore

i pressed retry

runtime error c;program filesaudacity1.3beta(unicodeaudacity.exe r6025) -pure virtual function call


Was that a one off error, or is it repeatable. If it is repeatable please give the steps to reproduce the effect.

i’ve recorded about 5 hours worth of itunes radio

open the file and ctrl a all of it.

bring the last three equalizer controls on the right down to zero

then start the process

shuts down after about 30 minutes with about 18minutes left

How much free space do you have on your C: drive?


i do get a popup that says i have 3483 orphanedblock files

I think that you are running up against a 32bit addressing issue.

Audacity 1.3 can handle files of any size, but Audacity uses shared libraries in the operating system that may not be able to do so. Depending on the sample rate / bit depth / number of tracks, I would guess that your recording is around 4GB in size. The maximum number that can be expressed with 32 bits is about 4 billion (a processor with 32-bit memory addresses can directly access 4 GB of byte-addressable memory).

If you are making very long recordings, use “Export Selected” from the File menu to export the recording in chunks that are well below 4GB. Exporting your file as 5 x 1hour sections will probably solve the issue, and will also make processing a lot faster.