line output to xlr mic input

[bogusblackman]

Hey, newbie here, just a probably simple question for anyone that knows what they are doing. (iow, anyone besides me) I want to hook up the 1/8" line out signal from a laptop to an XLR mic input jack in a room for doing presentations from the laptop. I know that the signals are different, and just wondering what i can do to connect the two. Thanks!!

[haldor]

Originally posted by bogusblackman
Hey, newbie here, just a probably simple question for anyone that knows what they are doing. (iow, anyone besides me) I want to hook up the 1/8" line out signal from a laptop to an XLR mic input jack in a room for doing presentations from the laptop. I know that the signals are different, and just wondering what i can do to connect the two. Thanks!!

More than you will ever want to know about the subject.

http://www.rane.com/note110.html

Don't forget the 1/8" jack on your laptop is unbalanced stereo. If you want stereo into the sound system you will need to use two mic inputs. Don't just short the left and right channel output from your laptop to make a mono signal.

Here is more about wyeing audio signals/

http://www.rane.com/note109.html

Phil

[Da5id4Vz]

The Rane notes are very good but I didnt see them addressing the difference in signal levels.

Assuming that the XLR input (female XLR connector) is truly a mic level input, your going to need about 30 dB of attenuation to match the levels.

Our friends at Tandy sell this little "gem"

http://www.radioshack.com/product.as...Fid=273%2D1374

at under $4 , its definitely a POS, but I have had surprisingly good results with it when used in similar applications.

-Dave

[Da5id4Vz]

I googled this out of the ether, it s a pretty good article on Pad construction:

http://www.uneeda-audio.com/pads/

Combine this with the radio shack transformer (no its not audiophile quality but it doesn’t need to be) and follow the Rane notes for bridging the left and right audio channels and you should be in business.

-Dave

[Aud_Mot]

A passive resistor pad is all that is needed.

Here is a useful link:

http://www.mcsquared.com/dbframe.htm

Click "T and H-Pads" at the top of the page.

Some experimentation is to be expected. Too many variables and equipment(s) with various output levels and input pads and gain stages to give a one size fits all answer.

Good Luck,

Aud_Mot

[haldor]

Originally posted by Da5id4Vz
The Rane notes are very good but I didnt see them addressing the difference in signal levels.

Assuming that the XLR input (female XLR connector) is truly a mic level input, your going to need about 30 dB of attenuation to match the levels.
-Dave

Umm, I've never seen a piece of gear with an XLR mic input that didn't also have a trim or gain pot. Typical range on these pots is 0 to 60 dB of gain. Don't forget that pro audio gear uses +4dBu for the zero level while consumer audio gear uses -10dBu for the zero level.

I connect consumer audio gear to audio mixers on a regular basis and have never needing to add an external pad to do so.

Phil

[Da5id4Vz]

Guess Ive just been "lucky"

[trwh]

A DI box (or two) is the right tool for the job.