Audacity Forum

Hi,
This is a magnificent program. Damn!!
I'm recording from my turntable through the MIC outlet on my sound card, but am getting a background noise, which I have been, pretty effectively, able to remove with the noise removal function.
My questions are:
1) Am I doing this the best way? I assume the noise is due to the fact that there is no amplification between the turntable and the computer. Is there a way of reducing the signal to noise ratio while recording?
2) Is there a way of increasing the volume of the recorded piece? (It's not very loud.)
3) How do I jump ahead on the recorded piece, without having to wait for it to play to where I want to go?
Thanks,
John

1) Most turntables have a low level output that is designed to plug into a phono (turntable) input. If you are plugging into anything that does not have a special "phono" input, the turntable should first be plugged into a phono pre-amp, which will amplify the signal and apply suitable equalisation for plugging into a "line input". Occasionally turntables will have a pre-amp built in, and can be plugged directly into a "line", "AUX" or "Tape" input. If the turntable does have a built in pre-amp, it must NOT be plugged into a phono input, as the phono input is likely to be damaged by this.

Microphone inputs on computer are notorious for being low quality. Also they are designed specifically for microphones and are not suitable for turntables, whether they have a pre-amp or not.

It sounds like your turntable does not have a built in pre-amp, (you should check this), in which case you will need a phono pre-amp. Also, if your computer does not have a "line in", then you will need a soundcard that does.

You will then be able to record at a suitable level, and the signal to noise will be greatly improved.

3)Use the "zoom out" tool so that you can see more of the recording - also you may use the scroll bar at the bottom. Then click on the waveform at the place you want it to start and a vertical line will show. You can now press the play button (or press the spacebar) and it will start playing from the position that you have selected.

Hi Steve,
Thanks for the help. That hint about moving the cursor made life much easier.
By using the "Noise Removal" function, followed by the "Amplify" function I have managed to get a fairly good copy, at an acceptable volume. The only problem that remains is to try and remove the pick sounds caused by the occasional scratch on the vinyl. Do you know of any way or removing/suppressing these?
Thanks,
John

John,

There is a Click Remonal effect in Audacity, but I personally I have never had much joy with it - so what I have done is to remove them manually. Version 1.3 of Audacity is much better for this as the developers have added a new "Repair" effect - this will mend a broken portion of waveform, up to 128 samples, by interpolating from the neighbouring waveforms.

To use it you really need to zoom in (use the magnifying glass icon) to the level where you can see the individual samples (little dots will shoe on the waveform). Then select up to 128 samples 1.3.x has a counter display at the bottom to help with this - then click Effect/Repair (if you are doing a lot of repairs then so long as you don't use any other effect meanwhile then Repair will remain the current effect and you can use the Ctrl-R shortcut. In 1.2.x of Audacity you will have to instead use the pencil tool to redraw the waveform manually. It's probably worth testing the repair before moving to the next one.

BTW: a useful tip for finding the clicks is to use the "Spectrum" view of the project rather that "Waveform" - click on the little downward pointing triangle in the control box of the track to get a dropdown to do this. Clicks/pops will show up as strong bold vertical lines. But I recommend switching back to the Waveform view for the actual Repair.

If you get a really big click/pop that's bigger than 128 samples then you can try selecting the whole lot and deleting the offending noise. This however may leave you with a disjoint waveform (which would sound like a click itself). To solve this, simply zoom in as soon as you have done the delete without moving the cursor. Then select some samples either side and apply the "Repair". This does not always work - so certainly test this and use the Undo function to go back to where you were before (i.e. undo the Repair and the Delete).

This manual process is very time consuming, but produces excellent results - well worth doing if you have treasured recordings that can no longer be purchased on modern media.

BTW: I also use Audacity mainly for transcribing/repairing vinyl & tapes - and 1.3 has proved well stable enough for these relatively modest needs (you will also get better label handling in 1.3 as an added bonus).

The above technique is good if you only have a few clicks to repair - if you have some very scratchy recordings then you might want to consider additional software - I have recently started using ClickRepair http://wwwmaths.anu.edu.au/~briand/sound/ - it costs US$40 but is a good tool that produces excellent results

WC

Thanks WC,
I will certainly try this. So I guess I should switch to version 1.3. Fortunately I have only a few clicks on each piece, maybe 10 or 15.
This audacity is a very good program.

Hi WC,
This click removal function works tickety-boo.
Thanks,
John