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Matching impedance from ear out to line on soundcard? Answered

I'm transferring old audio cassettes from an old cd-deck without line-out, so I have to use the ear-out for the signals to my soundcard's line-in connection.

I am educated in electronics as Raidio Offiser, but that was in 1976.

I'm also a hamraidio-operator since 1980 so I have made many transformers with toroids, building transmitters.

Well that is a long time ago so it would be nice to taking up the hobby with building electronic devices again. I am from Norway and we don't have a lot of companies like Radio Schack. I don't now any now. In 1980 it was lot of dealers, but after Internet came, all uses that to communicate.

Best regards from
Thor Andersen



You should be fine if you run the ear-phone out to the line in. Just use the line-in volume control (under recording-controls, not OUT) to attenuate the input.

Many if not most audio recording apps allow you to monitor the input for recording, so, you should be able to keep an eye on it once through to find the sweet spot.

I do it all the time

+1. The line input on sound cards is generally a high-impedance connection, and can tolerate most sources if they're in the right voltage range.

Yes it works ok, but a proper matching had been better.

My own casette-player had line out and I used that to transfered sound from it to my PC, but it is a long ago time since I gave that player to a friend.

As a ham-radio operator I have monitored RTTY signals from the shortwave band with the ear-phone output on a shortwave receiver, and got very good results. The RTTY board I made mysef.

I remember this now and maybee I can use the same circiut to get a steady level out signal.

Hi seandougue,

I have bought a program, VinylStudio, witch monitor the the signal in to soundcard all the time.

I use a spillter from the ear-out and have a head-phone in paralell with the signal I send to the line-in on the sound-card. That gives a much better signal in to the PC.

Best regards

Hmm...good!. I wonder though why you don't use the headphone OUT of the sound card to monitor the live mix? It seems to me that you'd get a better impression of what the sound card is actually recording that way, since what you're doing now monitors only the initial mix from the tape player. (splitting the source signal also represents a potential noise source from the extra load of the headphones and its wiring.)

That is use the program to monitor the signal level, and use the soundcard headphone out to monitor the recorded audio stream aurally.


Ok, I do monitor the out-signal from the soundcard and the sound is ok with the right level on cassetteplayer and the line-in signal.

The program has also a lot of filtering so the sound is 'better' than it is on the cassette when I'm ready with prossessing the sound on my PC.

Maybee this is not importent for recording sound from ear-out, but I want to do it the 'right way': Line-Out to Line-In.

Thank's for the info about headphone, I don't monitor with the headphone on the output, but with another headphone from the headphone-out on the sound-card in the PC.

Best Regards


7 years ago


the question is:

matching the output impedance in the earphone out with the line in impedance on a PC sound card.

I now use the volume control, but I just wantet to make a proper line-out from the ear-out connection.

It works with the volume control, but I want a proper line-out match:

best regards

What's the question Thor ?