How does one copy cassette tapes to computer?

I have a friend who wants to save his recordings he has on cassette to his computer. Are there any products out there that could do this, and how would one go about it? I would be interested in knowing the answer to this myself. I know there are products out there for transferring vinyl to the computer, but what about cassettes?
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With this; you can input the casette deck's signal, via your computer's stereo mic input and a stereo 1/8" to dual RCA adapter. You can then save the files to a wide variety of formats, at various sample rates, of your choosing(ie: Hi-Rez MP3):( There's a free sample download available.
Just to add to Rodman's and Elizabeth's responses, yes most computer audio cards have a line input jack (usually color-coded blue). You'll need the cable that Rodman mentions and some software to receive and store the signal. Rodman mentions Mixcraft which will work fine but only for 14 days - then you have to buy it. Another option is Audacity which is free. Just set either to take their recording input from the Line In jack, start the recording function, start the tape playing and you're off. You can then use the software to edit out any "clunks" you get from starting and stopping the tape, chop it into tracks, etc. I believe there are even functions to minimize tape hiss unless you're trying to be a purist.
I can't help with recommendations for doing that on a PC but on a Mac the combination of the 1/8" to dual RCA adapter to the built-in audio input and the "CD Spin Doctor" application that comes as part of the Toast software package works well.

He'll get one complete audio file per cassette side. If he wants to separate those files into individual tracks it can be done manually with any number of audio editing applications. Audacity is a good free one for both Mac and PC platforms. There is a function in CD Spin Doctor to automatically separate the tracks but it almost always requires some manual tweaking. I found it was too time consuming to separate the tracks so in most cases I just play the entire side, just as you would do on the cassette player.
Another approach would be to purchase a separate interface unit that provides an analog-to-digital conversion function, and outputs the digital data via one of the standard computer-compatible digital interfaces (USB, Firewire, etc.). A vast number of such devices are available, at all kinds of price points:|0&ci=14834&N=4294550051&srtclk=sort

I have no Mac experience, but in the PC world I would expect that one of these devices, if well chosen (be sure to review the user comments on any device being considered) would provide much better sound quality than a typical inexpensive consumer-oriented built-in sound card (or equivalent circuit on the computer's motherboard), in part because of inherent differences in their quality, and in part because of the proximity of the built-in card to digital noise in the computer. (I realize we are talking about cassettes, with their inherent quality limitations).

Rodman -- when you referred to the computer's "stereo mic input," didn't you mean the computer's "stereo line input," the mic input probably being too sensitive?

Learsfool -- On desktop PC's, at least, the stereo line input jack is color coded light blue, and will be located near the lime green line-out jack that is probably connected to the speakers. This is an example of the required adapter, if the built-in sound card approach is chosen.

Best regards,
-- Al
Also, if by any chance a digital recorder is available, such as those that record onto flash memory cards, another approach would be to record the output signals of the cassette deck onto that, and subsequently copy the digital file to the computer, either directly from the digital recorder, or from the memory card itself (via a memory card reader). Here are some digital recorders, again covering a very wide range of price points.

That approach would certainly eliminate the sonic degradations that might otherwise result in the captured file from computer-generated noise, although a good quality recorder will probably cost at least several hundred dollars.

Best regards,
-- Al
Hello Al- Mixcraft can use the stereo 1/8" mic input and(if needed) levels can be adjusted by navigating the computer's 'Recording Devices', 'Microphone Properties' and 'Levels' windows(re: Windows Vista). I've got Mixcraft on my laptop(no Line-Ins), and often use it to record directly(Mic-In) from the AUX OUTs of the Mackie Onyx 32.4 on which I mix(weekly gig). I've saved a large number of audio casettes, going to the 1/8" mic input(mic level set at 85), then burned Audio CDs from the files. The program simulates a mixer console, and multi-channel digital audio recorder. It can work with an audio input card, with Line-Ins, as well. It won't, "arm" a mixer channel, unless something is plugged into an audio/mic input and speakers/headphones are connected(gotta have analog ins and outs).
Rodman, thanks for the informative response.

What I was envisioning was the possibility that the mic input circuitry would be overloaded by a line-level signal before the signal information ever reached either the Windows software or the application software (Mixcraft in this case), unless the output level control on the cassette deck is turned down near the bottom of its range. But given your experience, and the fact that like your laptop Windows-based laptops commonly just have what is labelled as a mic input, and not a separate line-level input, I suspect that the gain and overload points of those inputs are not too different than those of the line-level inputs of separate audio components. I believe that the cheap electret mics which are commonly used with those inputs provide considerably higher output levels than most high quality mics, which would seem consistent with that suspicion.

A pet peeve I've had for some time is the lack of meaningful specifications for the analog audio ports on computers and computer sound cards, which generally makes it impossible to predict things like gain, level, and impedance mismatches with certainty.

Thanks again. Regards,
-- Al
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Thanks very much for the responses, everyone! I will relay this info to my friend, and also possibly make use of it myself when I get the time!
I use a Nakamichi Dragon into an M-audio Delta 1010, running Steinberg Wavelab recording and mastering software. An M-audio Audiophile 194 sound card would be less expensive and almost as good. Unfortunately, many recent brand-name desktop computers lack an extra PCI slot. Aside from the playback cassette deck, the quality of your A/D converters will be the limiting factor. Unless you are a computer wizard, there is a steep learning curve to configure and learn to use this stuff.