Converting cassette tapes to a digital audio format

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The above pictures apply to "Oye Como Va" by Carlos Santana, converted from a cassette to CD.



The clipping was from the tape I got converted by a friend from cassette tape to CD. I guess he had the recording levels wrong. I get another chance now.


Bob, to avoid clipping is it enough to use the Audacity 'show clipping' feature and adjust accordingly?


6. set playback volumes for digitization at peaks below 0DB - otherwise clipping
 
from my experience, as long as the analog output does not exceed 0DB
(according to the display VU meter - on all cassette decks) then you're OK.

I assume that audacity understands this - that some incoming signals
that is equal to 0DB does not clip. I assume audacity knows and does this.

A long time ago, some dolby encoded tapes added a dolby calibration tome
at the beginning of the tape to match the dolby marker on the VU meter
and as I recall, it was also 0DB or max the tape could output. this meant
that if your digital recorder could match it, you would not get clipping.

i would test all this, for one tape, match audacity to the loudest you find in,
say, the first minute. then find another tape section that is louder,
record it, then listen for distortion.

one of the bigger probems is that over the decades, using hundreds of different
tapes, the recorded levels is all over the territory.

I would then find the loudest record levels of a loud tape and match the
digitization to that. then almost all tapes will come in unclipped. some will
come in (digitized) with lower overall volume.

bottom line: its best to "under" then you coud use Audacity to UP levels. or
use some DAP's feature to equalize playback volume so you don't have to
adjust the volume for each track.
 
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Just a hint:

Depending on which deck the tapes were recorded, I would after cleaning the heads adjust azimuth aligning for the tape inserted before recording. This ensures You get the last juice from the tape.

On earlier days I used to use Soundforge (now Sony Audiostudio), but I'm sure You are fine with any audio editor / recording software)

My brother is now experimenting doing the same thing but with old Video tapes.
 
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from my experience, as long as the analog output does not exceed 0DB
(according to the display VU meter - on all cassette decks) then you're OK.


I would then find the loudest record levels of a loud tape and match the
digitization to that. then almost all tapes will come in unclipped. some will
come in (digitized) with lower overall volume....


This sound like a good idea. If you are familiar with Audacity or any other software, are there any other settings that would help improve the tape sound? Noise reduction and equalization come to mind, as well as lowering the amplitude to a level where it does not clip.
 
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Analog tapes are typically recorded over 0dB in peaks.


Had a look at your site. As usual I find a whole lot of equipment that I cannot make head or tail of, as well as some Dire Straits album pictures, so I have one of those very albums to convert, "Brothers in Arms" maybe I will post a converted clip.


As an aside, is that an amplifier in a wooden case you have at the lower end of these pages: I think I can work with wooden cases for amplifiers but not metal ones. Metalwork at home is out of the question.



Audio Pages
 
music soothes the savage beast
Joined 2004
Paid Member
from my experience, as long as the analog output does not exceed 0DB
(according to the display VU meter - on all cassette decks) then you're OK.

I assume that audacity understands this - that some incoming signals
that is equal to 0DB does not clip. I assume audacity knows and does this.

A long time ago, some dolby encoded tapes added a dolby calibration tome
at the beginning of the tape to match the dolby marker on the VU meter
and as I recall, it was also 0DB or max the tape could output. this meant
that if your digital recorder could match it, you would not get clipping.

i would test all this, for one tape, match audacity to the loudest you find in,
say, the first minute. then find another tape section that is louder,
record it, then listen for distortion.

one of the bigger probems is that over the decades, using hundreds of different
tapes, the recorded levels is all over the territory.

I would then find the loudest record levels of a loud tape and match the
digitization to that. then almost all tapes will come in unclipped. some will
come in (digitized) with lower overall volume.

bottom line: its best to "under" then you coud use Audacity to UP levels. or
use some DAP's feature to equalize playback volume so you don't have to
adjust the volume for each track.

How to make excellent recordings - The Walkman Archive
 
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A sample of the recording

You may draw unwanted attention from copyright holders by posting conversions of commercial recordings.

Maybe just a few bars here and there wouldn't get you in too much trouble.

Cheers


I have decided against hosting even a short clip of the recording, however I am posting a spectral analysis of a short clip, which tells its story. For comparison, a spectral analysis of another file, an .ogg file, from Track 2 of the Bee Gees "Main Course" album. High end is lacking, and it can be boosted satisfactorily with bass and treble. I will look at equalization after playing through my desktop system.
 

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Getting this recording took some doing. The USB input as audio did not work with my laptop, either in Linux Mint or Windows 7. Maybe it was a defective cable (supplied with the kit) although the 'plug and play USB device' was detected. I had to resort to an old laptop with separate microphone and headphone jacks, the Compaq NX-7010 which seemed to have been a high end PC in its day: I bought it used as a temporary replacement when my laptop was out for repair.


The spec for the ports on the NX -7010, being sold on e-bay for around $35 without battery and hard disk. Not bad.



1 x docking / port replicator
1 x audio - line-out/headphones - mini-phone 3.5 mm
1 x microphone - input - mini-phone 3.5 mm
1 x modem - phone line - RJ-11
1 x network - Ethernet 10Base-T/100Base-TX - RJ-45
1 x infrared IrDA
3 x USB 2.0 4 pin USB Type A
1 x IEEE 1394 (FireWire)


After getting an input signal I adjusted levels to reduce clipping to one or two rare occasions in the song. I played the entire tape through, stopping a tape mid way causes problems for the tape as I have found in the past, and recorded a large clip of several megabytes in .wav format.


I was surprised by the result. The tape played without any detectable wow and flutter, and as I recall at the correct speed. This I can check against the YouTube version. It was all there, the music from 36 years ago, I had occasionally listened to this tape in its highly muffled form a few years ago, but nothing like this. Definitely recoverable. CrO2 tape, it is, one of the first I think, and was played over 1,000 times at least.



The quality is acceptable, now if I can only get the USB connection working...
 
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1. Try and download, most songs are available.
2. For personal recordings, make a wire from stereo jacks and so on, cassette player out to mic in on computer.
Record as analog or .wav file, in real time.

Use volume control to set level, use the output from an amp (headphone jack, if volume is controlled).

Then play from computer, check how it sounds.
Then make a copy, or convert the file to a digital format, keeping the original saves you trouble if you don't like the digital conversion.

You can try different bit rates, sampling depths and so on.
Also you can try MP3, FLAC, Ogg Vorbis, later formats.

The chosen format should suit the player you will use to play the digital file.
 
1. Try and download, most songs are available.
2. For personal recordings, make a wire from stereo jacks and so on, cassette player out to mic in on computer.
Record as analog or .wav file, in real time.

Use volume control to set level, use the output from an amp (headphone jack, if volume is controlled).

Then play from computer, check how it sounds.
Then make a copy, or convert the file to a digital format, keeping the original saves you trouble if you don't like the digital conversion.

You can try different bit rates, sampling depths and so on.
Also you can try MP3, FLAC, Ogg Vorbis, later formats.

The chosen format should suit the player you will use to play the digital file.
Thanks for this information. I will try this.
 
Audacity is free and it has a track save feature for breaking up long recordings. I would not bother with commercial music. I would just buy, borrow or download a digital copy. Ripping CDs is very fast and even windows media fetches the tag data for you. You will want MP3tag to organize your music files. Back when MP3 was new, I preferred WMA compression, but a DVD player that I had only supported MP3 so I moved to a higher data rate MP3s. Today you may want to use lossless files like flac. If you are saving audio cassettes, there is little point worrying about hardware. A typical "soundcard" will be better than the tapes, but you should use a "line in", not an attenuated mic in. The fact that few people use a line in has complicated this issue. ie some ~laptops have no line in. You can buy a simple cheap USB audio in+out.
 
1. Try and download, most songs are available.
2. For personal recordings, make a wire from stereo jacks and so on, cassette player out to mic in on computer.
Record as analog or .wav file, in real time.

Use volume control to set level, use the output from an amp (headphone jack, if volume is controlled).

Then play from computer, check how it sounds.
Then make a copy, or convert the file to a digital format, keeping the original saves you trouble if you don't like the digital conversion.

You can try different bit rates, sampling depths and so on.
Also you can try MP3, FLAC, Ogg Vorbis, later formats.

The chosen format should suit the player you will use to play the digital file.
Hi,

My dad has old cassettes, which he wants to convert them in CD, So Which software or gadget I can use?
 
music soothes the savage beast
Joined 2004
Paid Member
I have coverted many cassettes and rtr tapes, lp's too into files.
You need computer with soundcard. I use external, soundblaster extigy. Its old i know, but still good enough.
Then you need software, i use sony soundforge. Its not free, but its great. It allows lots of editing. I make each song separate file, with fade in and out, i adjust levels and so on. Typically i do not use eq, only if it is really required.
Most of the time i use wav files, uncompressed. But if you want to save space, save as mp3.
Then burn. These days i just load to memory stick and share.
Its all fun, but time consuming.