external soundcard and boombox?

[badgrplayer]

Hello,


I use an old but nice multimix 4 usb to plug my guitar on my computer.

The other day I figured : what if I plug the headphone output of my boombox or my stereo system to one of the line input of my multimix? This way I could copy compact cassette or vinyl onto my computer?

Of course, the sound would be terrible, but it's just for fun. However, I'd like to know if there's no risk that I blow up my soundcard or my computer or my whole electrical system?

I'm not really an expert when it comes to impedances and voltages rules and stuff...

[whyterabbyt]

The other day I figured : what if I plug the headphone output of my boombox or my stereo system to one of the line input of my multimix?

Of course, the sound would be terrible, but it's just for fun. However, I'd like to know if there's no risk that I blow up my soundcard or my computer or my whole electrical system?

Electrically, there's no issue. But if you connect your stereo headphone socket to a single line input, you'll be recording in mono. You probably? want to record both channels, so you'd need a cable like this:

https://www.amazon.co.uk/3-5mm-Stereo-6 ... B0034DSUMK

[thecontrolcentre]

If your stereo system has a tape out then use that. If using the headphone out make sure you gain stage properly.

[Saffran]

Headphone output should go to mic input.
Aux output should go to line input.

[JCJR]

It ought to work fine. Sound quality would depend on how badly worn your records and cassettes, how badly worn the record stylus or tape heads and amount of natural electronic noise/distortion in your boombox/stereo.

Long (LONG!!) ago when most audio was transformer coupled, good signal gain and tone depended on matching output and input impedances.

But nowadays you generally get good gain and do not compromise tone so long as the source output impedance is lower than the destination input impedance. A headphone output will virtually always have a lower output impedance than the input impedance of your mixer channels. Also the level of the headphone output will "generally" be roughly in the same ballpark as ordinary audio line level signals.

Usually if you turn up the stereo/boombox volume knob it also turns up the headphone level, so you might find it convenient to mark the stereo volume knob and maybe the alesis input knobs with a little bit of tape or a felt pen mark, after you find a good record level, so that it will be easy to return to a good record level setting day in day out without having to think about it every time.

I wouldn't try to record as hot possible into tracks, because then a loud track might distort and you have to turn down and try again. I would record maybe peaking -6dB or whatever into computer as first step. Then normalize or otherwise raise the final playback gain with maybe a safety limiter plugin, adjusted conservatively (just rarely goes into gain reduction), as a second step before encoding to mp3 or flac or whatever you like.

If you have some stuff worth the trouble to clean up, there are various spectral noise reduction plugins and vinyl click/pop/crackle plugins. Sometimes they can work miracles.

Such takes enough time it is only worth the trouble on rare audio you can't conveniently get any other way.

Tis been a long time since I used noise reduction tools. Dunno of they have changed or improved. In my experience they worked fabulous until noise got bad enough to pass some threshold of badness. Once it gets just a little too noisy, tended to degrade from "surprisingly good" results down to "results so bad it sounds worse than the unprocessed audio".

So after awhile I learned about when to give up. If NR was gonna work at all it would do so with minimal fiddling, so if it doesn't clean up quickly then give it up as a lost cause.

Maybe it's somehow different nowadays.

[badgrplayer]

Electrically, there's no issue. But if you connect your stereo headphone socket to a single line input, you'll be recording in mono. You probably? want to record both channels, so you'd need a cable like this:

https://www.amazon.co.uk/3-5mm-Stereo-6 ... B0034DSUMK

Oh yes, stupid me!

I must have one of this cable somewhere. I'll try.

Thanks for the other advices as well.

[whyterabbyt]

Tis been a long time since I used noise reduction tools. Dunno of they have changed or improved. In my experience they worked fabulous until noise got bad enough to pass some threshold of badness. Once it gets just a little too noisy, tended to degrade from "surprisingly good" results down to "results so bad it sounds worse than the unprocessed audio".

So after awhile I learned about when to give up. If NR was gonna work at all it would do so with minimal fiddling, so if it doesn't clean up quickly then give it up as a lost cause.

Maybe it's somehow different nowadays.

For broadband noise, transient interruptions (clicks etc) and removing background sounds they can be scarily good these days; where they tend to be more touchy and potentially start to introduce artefacts tends to be more difficult stuff like de-reverberation and de-distortion.

[nix808]

imo- a headphone out is hotter than both line or mic,
just be a bit careful with headphone amps,
they have more wattage than line or mic