Line-in jacks in MONO?

Do you have a question? Post it now! No Registration Necessary.  Now with pictures!

Threaded View
I was really decided on buying a particular HP laptop when by chance I
glanced at its service manual online. The mic-in (audio-in) jack is MONO
(monaural); not stereo! I checked a couple of other HP laptops' manuals too,
and some others (including their high-end 17" P4 model) also have a monaural
audio-in jack. I couldn't believe it.

I looked at Sony's site and saw mono line-in jacks there too! That's when it
hit me: this must be some kind of copy-protection-thwarting attempt. That's
always an easy workaround to whatever DRM the companies come up with
(they're talking about copy-protecting plain old audio CDs now)....just play
the CD on an external device and record its (analog) audio directly into the

Having a mono input jack may discourage some people, as they probably won't
be able to tell why their "recording" of their CD doesn't sound right (maybe
it's only recording the Left channel??). Of course, this would only drive
people (myself included) to buy a decent sound interface (probably PCMCIA)
to record into.

Anyone know why some companies are penny-pinching to the extreme with these
mono audio-in jacks? I can't imagine it saves more than a few cents.

Better yet, anyone have one of these laptops whose specs say the jack is
MONO but actually can record analog audio in stereo? Just wondering.


Re: Line-in jacks in MONO?

Quoted text here. Click to load it
Quoted text here. Click to load it

Mic-In Jacks on computers are normally mony.  Line-In are usually stereo,
but where they double up as is common on lap tops, mono is the rule.  It's
not a copy protection thing, just penny pinching.

Re: Line-in jacks in MONO?

Quoted text here. Click to load it

I'd want my mic-in jack on my laptop to be mono, as I'd always be
connecting a single mono-mic headset to it.  (I'll leave the details
of phantom power for the mic element on the ring terminal for another

If you'll be recording music on your laptop, you really don't want to
be using analog inputs anyway, you'll want to use a (probably
USB-based) external solution.

Re: Line-in jacks in MONO?

It's not copy protection, it's cost-cutting.  The Mic in jack is mic in,
it's not intended to be "line-in", which most laptops do not have.  The
solution is an add-on sound card.  Both USB and PC Card sound cards are
available that have a full range of I/O's, and also much better sound
quality (the inside of a laptop is electrically noisy and is a bad place
to do A-to-D conversion of low-level audio signals).

Fr@nk wrote:

Quoted text here. Click to load it

Site Timeline