Equipment impedance matching for recording...

[arfarf]

Direct line-in recording from a Zoom - level control

So, I'm playing with my home recording and considering my options. I'm recording guitar into my PC directly via the line-in. My set up looks like this:

Guitar->Zoom 505II->Creative SB-PCI 128 Line-in

And the sound quality isn't bad. However, here's my problem...
When recording, I'm generally pegging the meter - making editing very difficult. I've considered buying a mixer to fix the levels, but today I did a little research, so I'm still on the fence.

The input on the SB says it's 0-2vpp with an impedance of 47k ohms. The output on the Zoom says it's max output is +5dBm/output load impedance 10k ohm or more (which I'm assuming is basically Walkman(tm) output, as the Zoom is set up to take headphones direct).

Given all this, I'm assuming that my overdriving problem is just a case of impedance matching, only as a nube, I have no idea how to match the impedance. I'm not afraid to solder, but I have no idea what type of circuit/resistor/impedance matching devices I would use to solve the problem. If I could solve the problem at Radio Shack for $20 I'd probably build something rather than popping $100+ for a mixer, or (gasp) input box like the Fostex, M-box, e-Mu, or whatever.

Any help would be greatly appreciated.

I also have some other fundimental problems with synchronization in general, and recording with MIDI. My toy box looks like this today:

2 guitars, one electric, one Ovation electro-acoustic
Some guitar effects, including the afforementioned Zoom box
Yamaha PSR-290 MIDI keyboard
A practice amp
Loads of computer gear and cables to connect stuff (all of it is well... connected)
I've been recording with Acid Pro/Vegas/and other packages.

 

[boingoman]

The impedances are fine. Pretty much any line-level out will be fine plugging into any line-in.

Your overdriving problem is from level-matching. Most likely the SB card can't handle the signal from your Zoom. Consumer "line-level" is lower than MI and pro line level.

A mixer will help, as it will be less noisy at lower output levels, unlike the Zoom. You can crank the Zoom into the mixer, and send a smaller signal to the card.

Best thing is to get a card that handles +4 line inputs. Your SB probably is a -10 unit.

 

[DigitalSmigital]

The 505 has no trim knobs...

as I recall, so your only choice is to use the knobs on your guitar or build an attenuator .

 

[arfarf]

No trim...

You are correct, there's no trim knobs on the Zoom. I tried cranking the gain down coming out of the Zoom, and cranked the volume down on the guitar going into the Zoom, but as you can figure, that's unacceptable, as one of the things that makes me like the configuration I have is being able to crank it into the Zoom and have the Zoom crank up the gain.

I'm open to building an attenuator, if that seems to make the most sense, but I'm not sure how to calculate the parts needed for my desired results. I actually have a little Radio Shack "attenuating" stereo cable between the Zoom and the line-in (out of lack of a cable, rather than an attempt at fixing my problem). I don't know how much it reduces the signal, I just remember the label on the package said "attenuating".

I've been looking at the input cards/boxes I mentioned above (Fostex, M-box, e-Mu - I'm just assuming they would handle the output of my Zoom at the right levels), but I went to my lame-o local music store, and and they didn't have much for me to play with...they did have some consignment mixers that were interesting.

Do you guys think it would be better to invest in a nice generic mixer, or a specialty computer input device. As I type this, I'm thinking in the long run, I'd be happier with the generic mixer, as I could have friends over, plug in, and all run into the same amp (or whatever).

 

[Farview]

This thing doesn't have a volume control for the headphone jack? Or even a level inside the patch you are using (not the gain)?
I seem to remember running into headphone extentions with built in volume controls, if they still make them, that will help.

 

[arfarf]

Actually, that's not a bad idea...

I know they have in-line volume controls for headphones, I could probably find one with a male on one side, and female on the other, and use the volume control for my mixer. At least, until I decide I've "outgrown" it...

http://www.radioshack.com/product.asp?catalog_name=CTLG&product_id=42-2559

Catalog #: 42-2559 - US$6.59

Didn't even think about that... thanks!!

I'll post once I find out how well it works.

 

[arfarf]

Ok, now I feel stoopid...

There *IS* a master volume level on the Zoom 505II. It's not intuitive, so I pulled out the book... right on page 9...

"Keep both [+]/[-] keys depressed for more than 1 second." then you can crank down the volume (which defaults to 40 when you power the unit off).
The level can be 0-50.

Setting the level to "20" makes it fine for all but my most juiced up patches.

Thanks for the ideas!!