View Full Version : I'm needing help on converting cassette masters to digital

2014-05-30, 10:50 AM
Hi Traders,

I recently re-aquired some tapes I had in storage for 10 years or so made up mainly of bands I personally recorded in Toronto. Samples include: Husker Du at Larry's, Smths at Kingswood, Dinosaur Jr at the Cameron, Butthole Surfers and RPM, etc from the early 90's to late 90's. None have been previously circulated and I want to share them here. Eventually.

I bought a used high end tape player and am in the process of converting to digital on my Mac using Audacity but am having some questions arise as I do this process.

Some of my problems so far involve:

- When to 'normalize'?
- How do i best seperate a 45 min side to seperate tracks?
- How do I handle tape speed issues or detect speed / azmiuth issues on the master? How do i fix these?
- Some times after too many beers, my Sony Walkman D6 Pro would have the mic pop out partially, and one of the audio tracks would drop off until I noticed and re-plugged the mic. How do I copy/paste from the good channel over top of the bad until the correction was made essentially going mono for a short time? I can't seem to see how a copy / paste is done.

Can I get a tape --> digital consultant available for my questions?



2014-05-31, 06:09 AM
Audacity is fairly limited for what you propose to do there. Because of the fact that it is a live show, you probably will have to put in the track markers yourself.

Most people would probably leave the normalise button alone. It can be quite drastic sometimes when it is applied.

The only way to really detect the speed issues is by listening really. And be aware that bands used to play things slower back in the day.

Mic pops and clicks just happen, I wouldn't be too worried about, completists will just want to have the recording. Copying up the channel can cause strange effects (once did it for myself and ended up with a weird echo).

If you do want experiment with some of these things, maybe try a Digital Audio Workstation like Reaper or Audio Cleaner Pro.

2014-05-31, 07:37 AM
i'm with Karst, unless its borderline unlistenable i'd avoid a lot of the typical processing folks do...Audacity is fine for splitting tracks but thats about the extent

Track Splitting in Audacity
1. Open your wave file, Edit->Move Cursor...->Track Start and hit command-B.
2. Locate all your track splits and mark each one by hitting command-B.
3. Go to File->Export Multiple, select WAV as the export format, Split files based on:Labels, Name files:Numbering consecutively, hit Export.

for correcting tape speed fluctuations, my preference is Ableton Live's "time warp" function...imo its leaps & bounds above any other program for the task...but understand it is an extremely tedious & time consuming process, so be prepared for countless hours of work if you decide its necessary

i personally use Live w/ iZotope & Wave Arts plugins for mixing/mastering, but there's plenty of DAWs & mastering plugins out there like the ones he suggested above that'll give quality results as well

when in doubt, leave it "as is"...good luck :thumbsup

2014-05-31, 05:59 PM
Also, azimuth issues will have to be done via trial and error. Usually if your deck was in clean order you should be able to adjust it once at the beginning of each tape side. But sometimes it will change drastically from the beginning to the end of each side. Helps if you know your tapes

2014-06-11, 11:55 AM
"Normalization" causes a lot of confusion and is so controversial because there are some music programs that abuse the term and substitute an algorithm that effectively compresses the music. Compression is a type of lossiness where the dynamic range is lost forever, to be avoided. However, the usual kind of normalization is "by peak", where the software searches for the largest transient in the selected audio and calculates the factor that would result in that peak being very close to "1" (usually you have the option to set it to a little less, like 0.98). Then that same factor is used to simply scale the rest of the audio data. Since this is being done in 32-bit math there is no chance that it leaves any audible artifacts or accidental clipping. It would only be proper to normalize in this manner if you process the entire show at once, as one of the last operations before tracking. Also, there may be transients such as loud claps between songs that you may want to remove first to make the process more effective. As for tracking, good old CD Wave still works just about as well as anything else: http://etree.org/cdwave.html

2014-06-11, 01:39 PM
The complaints I've heard about normalization is the further truncation of sample values, unless of course the factor by which the sample are multiplied is an integer. In other words, if the sample values are multiplied by, say, 1.896 any product that is not an integer is truncated, and many folk prefer to leave it alone unless the levels are so low that the sample values can be multiplied by an integer without clipping. Frankly my ears are too far gone to hear a difference, but the math speaks for itself.