Audacity Forum

Hello, first off let me say how thankfull I am to the developers. This is an amazing tool. Thanks for sharing it with the world.

I have two recordings that were made in one of those 25 cent "Hear yourself on record!" booths back in the late 1950's. Unfortunately, by the time that my Aunt found them, they had been physically broken. She took them to some professional who did their best at recovering the audio. With Audacity, I've already been able to clean them up somewhat, but I want to make them better than that. They include the voices of my Grandfather and my Mom, Aunt, and Uncle when they were little kids. My Grandfather's voice brings tears to their eyes and I would love to make a late Christmas gift for them.

Before using Audacity, is there a way to bond the records back together, then use a stereo microscope to smooth the cracks/chipping by filling then leveling or buffing out the cracks?

I haven't had great luck with the click reduction or noise removal tools. The FFT effect is somewhat useful to bandpass each speaker's voice range and individual spoken word's tone. Is there a way to modify an Audacity effect to utilize the fact that the main noise artifacts occur on an interval corresponding to the rotational speed of the record?

Regardless of how I clean them up, I realize that the audio quality will never be great.

The files are 16 and 12 MB respectively and are the originals:
http://www.carnicopia.com/Misc/broken_album/Track01.wav
http://www.carnicopia.com/Misc/broken_album/Track02.wav

Any other words of wisdom?

Thanks,
Ryan

I started out using Audacity's tools - mainly hand-drawing the repair in 1.2 and latterly the manual Repair tool in 1.3.

But last year I started using ClickRepair - it costs a little but is well worth it IMHO. It does offer a 21-day free trial to assess the product, so with only two recordings to fix you should be able to do that easily within the 21 day free period.

See this thread I posted a while ago for more detail: http://audacityteam.org/forum/viewtopic.php?f=28&t=1994

WC

sparksnsaaben wrote:Before using Audacity, is there a way to bond the records back together, then use a stereo microscope to smooth the cracks/chipping by filling then leveling or buffing out the cracks?

I don't think so.

With Audacity you should be able to achieve some improvement using a combination of filtering and noise reduction.

You should use Audacity 1.3.6 as the noise removal has been much improved over the effect in version 1.2.x
(Since this is a mono recording you can convert the recording to a single mono track before you start - this will reduce the file size and also speed up the processing time a little.)

Processing should ideally be done at 32 bit for best quality.

Do the filtering first - try using the "High Pass" filter set to 24dB per octave and a cut off frequency of about 180Hz, then use the "Low pass" filter set at 24dB per octave and a cut off frequency of around 5000Hz.

Use the "Amplify" effect to bring the volume up.

Select a section of "noise" (without the voices) and duplicate it to a new track (Ctrl+D).

Amplify the noise sample by about 6 dB.

Use the "Noise Removal" effect to capture the noise profile from the amplified noise, then apply Noise Removal to the original recording with the reduction level set to about -18 dB, Frequency smoothing = 180 and attack/decay set to 0.1

Finally you could apply a little Equalization to tame some of the resonances.

I've uploaded a sample in MP3 format here: http://easyspacepro.com/audacity/exampl ... record.mp3

stevethefiddle, the section that you cleaned up is a big improvement over the results that I was getting.

I'm going to try v1.3.6, and different combinations of Click repair and Audacity's tools. The noise seems to change throughout each track (especially Track02.wav), so I'm going to try processing them in 10 second segments.

Thanks very much for the suggestions.

Well I've think that I'm done with one of them.

http://carnicopia.com/misc/broken_album ... _final.wav

Audacity 1.3.6 produced the best results using a few minutes of time working with each tool. I couldn't get it much better than my first few attempts. ClickRepair, DeNoiseLF, and DeNoise produced the overall best results but had a somewhat steep learning curve and took hours to get these results. In the end, what you're hearing is DeNoiseLF, ClickRepair, DeNoise, and then Audacity's tools using low pass filtering, equalization for the 1938 RCA profile, and then gain boosting in several sections. ClickRepair was amazing. One note about DeNoise, the best procedure for me was to make a pass at a somewhat lower than recommended noise level, re-sampling the noise, and then make another pass at a slightly lower level than the first (3 to 6 decibels or so).

The second track should go much quicker now that I've got a handle of how to use the programs. I'm not sure when I'll get around to working on the second track, but I'll post it here when done.

Thanks again,
Ryan