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output your microphone to a remote computer's speaker

Terminal - output your microphone to a remote computer's speaker
dd if=/dev/dsp | ssh -c arcfour -C username@host dd of=/dev/dsp
2009-02-08 10:10:00
User: morpheus
Functions: dd ssh
output your microphone to a remote computer's speaker

This will output the sound from your microphone port to the ssh target computer's speaker port. The sound quality is very bad, so you will hear a lot of hissing.


There are 2 alternatives - vote for the best!

Terminal - Alternatives
arecord -f dat | ssh -C user@host aplay -f dat

Know a better way?

If you can do better, submit your command here.

What others think

how do you... un-output it?

Comment by Svish 350 weeks and 2 days ago

Control-c ?

Comment by DavieBaby 347 weeks and 6 days ago


cat /bin/bash > /dev/dsp

which takes each byte and interprets it as a frequency (number of waves per second, HZ) and the sound driver plays it.

Comment by anzan 341 weeks and 3 days ago

wow, that looks really scary.

Comment by unixmonkey3883 339 weeks and 5 days ago

That is freaking awesome.

Comment by brephophagist 338 weeks and 5 days ago

Any hint to make this work on Leopard ?

Comment by sitaktif 334 weeks and 1 day ago

Would be sweet if i knew how to make this work for Leopard. Any thoughts?

Comment by fastrack20 333 weeks and 5 days ago

Leopard does not use /dev/dsp, so there should be some alternatives to it

Comment by foremire 321 weeks and 5 days ago

Has anyone found a solution in 10.5/6?

Comment by megrimm 301 weeks and 6 days ago

Do it trough SSH and output to your own machine and your a spy :P

Comment by Meeko 301 weeks ago

Mac OS X uses coreaudio to input and output sound. No UNIX sound device drivers are present, and, in fact, they are frowned upon by Apple as primitive and ugly. Thus, they will probably never be added to Mac OS X :-/.

Comment by morpheus 300 weeks and 1 day ago

Very Good!!!

Comment by alwaro78 274 weeks and 5 days ago

how did u find it?

Comment by deargodzw 235 weeks and 2 days ago

That's cool!

Comment by regding 208 weeks and 1 day ago

Since /dev/dsp is obsolete & missing from Ubuntu, what was that command to wrap those old programs to use PulseAudio instead?

Comment by klepsydra 185 weeks and 6 days ago

That is awesome. Pure CommandLineFu!

Comment by thecamelcoder 180 weeks and 2 days ago

for ubuntu i use this one "arecord -f dat | ssh -C user@host aplay -f dat" (replace the 'dat' with 'cd' to get 44100hz instead of 48000 quality is very good but not so heavy on the bandwidth)

Comment by srulikuk 127 weeks and 1 day ago

@srulikuk: I like yours better :-)

Comment by morpheus 127 weeks ago

I've successfully tested these between two Macs that have the sox binary:

Send microphone input from local machine to remote machine's speakers:

path/to/sox -V0 -d -p | ssh user@host path/to/sox - -d

Send microphone input from remote machine to local machine's speakers:

ssh user@host path/to/sox -V0 -d -p | path/to/sox - -d

The '-V0' is optional?I just prefer not to see the warning messages.

Here's the link for the sox download for Mac OS X:


Use the binary (the UNIX executable file named 'sox') inside the download folder.

Comment by member1936 72 weeks and 5 days ago

@member1936 : Hi, i tried but couldn't do the same between my two Macs with sox. I succeeded on playing a local wav file to distant speakers but when I try default input and output I have this : FAIL formats: can't determine type of `-'

Any advice, clue or idea ? Thanks a lot.

Comment by nitnok 67 weeks and 3 days ago

Your point of view

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