Transferring Cassette Tapes - Hiss and Wow

Hello. I’ve searched the forum and cannot find a discussion regarding the problem I’m having. I am in the process of digitizing my old cassette tapes. I’m using Audacity 2.0.6 and my Windows version is 7. The cassettes are mostly of radio broadcasts of concerts. I am transferring by running a cable from my receiver/amplifier (Vector Research) headphone jack to my PCs’ mic-in jack. Before I even start the playback on my cassette deck there is a lot, (between -24 & -12 dB), of hiss (not caused by the tape) and wow (an audible hum), so I’m thinking this noise is somehow related to the cables I’m using? Or is it something to do with the mic jack on my PC?

I don’t hear this noise when I record my voice live, (or use Skype), using a mic/headset.

The cable connecting the receiver to the PC consists of a headphone cable with a large male jack plugged into the headphone jack on the receiver, a converter that converts the female jack from ~1/4 inch size down to the more common size of today’s cell phone jacks (~1/8"), and then a male to male cable from the converter to the mic in jack on the PC.

If I eliminate the male to male cable and plug in a set of ear buds into the converter jack, the audio sound is “perfect”, (no hiss or wow). The male to male cable is ~3 feet.

I can eliminate most of this noise by using the Noise Removal feature of Audacity, but a better solution would be to eliminate the “ambient” noise I’m receiving before the recoding of the cassette even begins. Does anyone have any suggestions or thoughts on what might be causing this noise?

Thanks in advance.

Or is it something to do with the mic jack on my PC?

Yes… Too much gain. The noise is getting amplified. A microphone signal is a few millivolts. A line-level or headphone signal is around 1V.

You need a line-input. If your computer doesn’t have line inputs (desktop & tower computers do, most laptops don’t) you’ll need a USB audio interface with line inputs. [u]This page[/u] has a couple of recommendations. (You may need different adapter cables.)

and wow (an audible hum)

FYI - Wow is not hum… [u]Wow[/u] is low-frequency speed/pitch variation. Flutter is higher-frequency speed/pitch variations. All turntables & tape recorders/players exhibit some wow & flutter, but in a properly functioning machine it’s not audible.

These articles from the Audacity Wiki may be of use to you:

And this workflow tutorial from the Audacity Manual:


The Line in was the solution, I knew it was something fundamental that I was just missing! I WISH I had asked this about a month ago, I have a lot of re-transferring to do LOL :laughing: Thank you DVDdoug and waxcylinder!