is there a software -30Db pad on mic input?[NO! - solved with hardware)

[RickBrock]

Hi, I've discovered that the mic input on the Laptop is exactly that... a mic input.

So, everything distorts very easily when recording a line level.

When i drop the input of the volume on the ALSA mixer then i still get distortion, just at a quieter level.

so, my question, is there a software option to drop the input gain on the mic input to accommodate a line input?

Thank you

Rick

[GMaq]

Hi,

I really don't ever suggest using a line/mic input on a laptop directly for recording even just goofing around for the very reason you mention. Without spending a lot of money I suggest getting a small 4 channel mixer like a Spirit or a Behringer with at least a couple of XLR and line level inputs and let the preamps take care of all the signal attenuation for you and then just use the laptop input at line level from the mixer outputs. Option 2 is a supported USB device which will run a bit more money but likely have better A/D converters however there are limited devices that work with Linux although those that do work seem to work well so research before you buy.

Software will likely only decrease the gain of the incoming signal without properly attenuating the impedance thus the distortion regardless of level, AFAIK hardware is the only effective way to address the issues completely.

[trulan]

That really depends on your hardware, as you've discovered you're actually overdriving the preamp on the input.  Many laptop onboard soundcards are able to switch between mic and line input on the same physical plug.  You can try messing around with the options in gnome-alsamixer, as well as running alsamixer in a terminal and seeing what you can find there.  Also, check your BIOS, there may be a setting for it in there.

Or, do as GMaq suggested and pick up a basic USB audio device, if you plan to do a lot of recording.

[RickBrock]

Hi Gmaq and Trulan,
I thought that would be the answer - but i hoped otherwise....

Trulan, I tried with no results on the Alsamixer.... i shall take a look at the bios.

and.... I shall try this (a solution sent to me by a colleague) http://arrakis-systems.com/pdfs/Microphone%20Input%20to%20Line%20Level%20Adapter.pdf

what do you think?

in other news:

I have a TRUST (yeah yeah I know.....) USB 5.1 sound device. It worked well in windows because I had the drivers. it is a 5.1 out (6 channels out), a stereo line in and a mono mic in.

However... when i plug it into linux and look at it using patchage i am shown 8 outs and only one mono in. this is what happens when i plug cables into things
out1+2 = L&R
Out3+4 = front and Sub (as a guess, but it's 2 usable outs in any case)
out7+8 = RearL & RearR (again, just a guess)

OUT 5+6  = ???? I have no idea - but I've not tried to plug a cable into the 'line in' into the mixer... perhaps i should?????

then i have a mono mic in = mono mic in

so....... hmmmmmm...... I shall try 5+6 as i suggested above I think... and report back.

thanks for your time.

[RickBrock]

I solved my problem buy getting hold of 2 KlarkTekniK DN100 DI boxes.

2 unbalanced jacks (TRS) come out of my Yamaha mixer desk as group 1&2 (line level) into the two DI boxes.

I use groups 1 and 2 so that i can still monitor L&R while recording each track.

The XLR (Balanced) outputs (1 from each DI box) are then summed together using a crafty little cable i made which unbalances the 2 XLR female plugs (1 from each DI box) and Y-joins them together into one stereo Jack which plugs into my laptop.

both XLR's = join pins 1+3 to the sleave of the Jack
left XLR pin 2 = Jack tip
right XLR pin2 = jack ring

The results are quiet and clear so far.... 

happy days.