dj_stick

Ok with this small operation, on my Audigy card i managed to get an extra 4 analog inputs to record from, without doing much at all.

Note: Although modding the second front input is unnecessary - as the other soundcard will have a line-in port that you can use - some motherboards allow you to have 5.1 sound by swapping the line-in/mic ports for rear/sub-centre ports, and this therefore allows you to set you motherboard soundcard in such a way, while having an extra line-in at the same time, useful for if you use your onboard sound for games and the kX card for music (like my situation)

I was looking at the peripherals that came with my computer case, and i noticed it had headphones out and mic in ports… but was annoyed to see they had the jacks on the end, and had to send them out the back of the case and into the ports on the soundcard… i thought that was pretty useless - so i decided to do the following

What you need:
For all four inputs you need a 10k2 card and another soundcard that supports S/PDIF output and CD or AUX in (onboard sound in my case)
If you have a Soundblaster Live! card you can still use the secondary card.

Computer case with microphone and headphone ports (or the connectors themselves if you are building this from scracth)

Two (2) Analog CD Audio cables

Something to de-pin these with - i used a pinboard pin - not exactly safe though.

Method: (first steps may not be required if your case ports already use the standard pin-header type connectors)

De-pin one end of the CD Analog cable and put the plastic cover somewhere safe - you may need it later on

If your case uses the standard connectors - such as those used for USB,IDE and CD audio, then de-pin those that you are changing with the CD audio cable - replace these wires with the ones from the CD audio cable

Remember:
- the red wire is always right, white wire is always left, black wire is always ground.
-if one of these ports uses green and yellow wires, like mine did, i found that the yellow wire was right, and the green wire was left - you may need to check with a multi-metre or a buzzer device to be sure.

If you are building from scratch - instead of de-pinnning the CD audio cable, cut the end off and strip back the wires. Then solder on to the connection points of the jacks.

Once you have connected the jacks to the wires, it is time to hook up to the sound cards.

Using the AUX_IN or CD_IN headers on the card, make sure you get the polarity correct

If you are using two cards to do this, you should now have 2 sets of 3 or 4 (3 is the minimum required - 4 has two ground wires) wires running from the front of the case to the soundcards - or if you are using only one card (sb-live! or audigy(10k2) with no other soundcard involved), one set of 3 or 4 wires to the sound card.

Now it is time to connect digitally - use the manual for your soundcard or motherboard (onboard sound) to determine the polarity of the s/pdif header on a non-creative card, and for sb-live/audigy inputs use

Once this is connected you have completed the hardware side of things.

Once you have booted up your computer, if you have an audigy (10k2) card

click the start menu and press the "run" button

type "command" and press enter

in the command window type:
"kxctrl sac97 2 0" and press enter, then
"kxctrl shw 19 1" and press enter

remember: do not type in the quotation (") marks

This enables the routing of the rear line-in port to the higher quality I2S codec, and this port should be used when you need the highest possible quality possible with these cards.
This also frees up the AC97 codec to send an input that is useable in ASIO programs when kX is correctly setup

Open the control panel for your second card (if you are using one) and enable it to record from the source you connected the front panel to (either Auxilliary in or CD audio in). Make sure this channel is unmuted and volume is increased to ~±0.0dB (line level).

open the kX mixer and open the ins & outs page
unmute and increase the sliders of CD S/PDIF, AC97 and AC97 2 until they are at line level (±0.0dB)

open the ac-97 page and select the record source as the input you connected the front panel to (CD audio or Auxilliary in)

You should now be ready to record 6 input channels into an ASIO application. In the DSP route the inputs used from the prolog (AC97 2, AC97 and CD SPDIF) to the top of the ASIO section of the epilog for ease of use when selecting inputs in your ASIO application.

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dj_stick

sorry about no posting pictures - i only though of writing this up after i did the mod

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Rogacz

Good idea.

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dj_stick

if you try this yourself, please tell me how it works for you

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TravelRec.

Hi dj!

Posted this idea some time ago - but not so detailed. So your description may help some more.


Greeetings!

TravelRec.

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dj_stick

i just posted step by step what i did myself… so much easier this way than predicting what should be done - liek i did with some of the getting started guide

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TravelRec.

Yes,

that´s what I mean - think about all these people they don´t use a soldering iron 20 times a day... !

Cool work! I´m waiting for the pictures!


Greetings!

TravelRec.

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dj_stick

perhaps i will post pictures of the final thing… and maybe my method of de-pinning the wires (not exactly the safest way but anyway)

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TravelRec.

I do this almost with my pneumatic hammer that is standing in a unused corner of my studio !


TravelRec.

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dj_stick

my method is slightly different… i use a pin from a noticeboard, lift up the black flap thing and slip the gold connector out… also leaves me with a re-usuable socket if i need one again later on

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dj_stick

Update:
when i first used this method, i used unshielded wires, and had a noise floor of roughly -50dB
using shielded cables my noise floor has dropped to roughly -75 dB

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dj_stick

and for a pic of my DSP
the SRC plugins in the lower left corner are all renamed to the inputs, the peak metre was used for testing these

i also have several other modules and this is my "general purpose" dsp setup

http://djstick.topcities.com/dsp.html

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TravelRec.

Yeah - everytime use shielded cables for audio - wherever you go!!!
-75db are okay, have you checked the Philips UDA on I2S#1 (with kxctrl mod)? It should have around -82 db noise floor.

Greetings!

TravelRec.

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dj_stick

yes it does, but my mixer has a little bit of a noise floor (i connected my mixer to the input to check to see if it was working)

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TravelRec.

Yes,

every analog equipment has noise , just a simple cable has it. But this really dosen´t matter if the sound is good and fat - I also have a mixer (ZECK FME) on input sometimes, tweaking the gain is the most important thing to improve S/N ratio. To get the cleanest signals, I connect the sources directly with the external A/Ds, but sometimes this is not possible. Biggest "noisers" are always microphones and their amps, not the mixer nor input itself.

Greetings!

TravelRec.

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Nappylady

*bump*

The starting post on this thread (or maybe the whole thread) should probably go in the knowledgebase...

Travelrec, Stick... I've got an idea for a knowledgebase page... one of the hardest things about this "multiple card" stuff is figuring out which pins do what, and every card model is different. It would be great to have a page that listed, for every model #, what the pins look like and which pins are relevant to the endeavor.

I've got 3 models of cards here (SB0100, SB0220, CT4832) and I think I can figure them all out... I'll bet between the 3 of us, we could cover almost all of the models that are out there... That would make the whole kX project REALLY useful, since someone could start from scratch and have a real multitracker in a matter of hours, by consulting the KB.

dj_stick

perhaps that is a good idea… afaik there are only 3 differing pinouts
AUD_EXT all audigy and most live! cards
AD_EXT some audigy 2 cards
SPDIF_EXT live! value cards

all pinouts are now known to us… perhaps if you can take some photos of your cards wired together… i can integrate that with the text files i received from Doug W and add it to the knowledgebase… i will also take photos of the lil h/w mod i made for the audigy… ultimate addon guide

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dungle

hi,
what would be really useful is a simple block diagram showing what gets connected to what (no detail).
This would enable the casual viewer to understand the concept without having to read the entire article.
Then if it is of interest, one can read the entire blow by blow description of the details on how it is done.
cheers

dj_stick

i will add that to the guide when i hear back from nappylady… it will be a few pages on the knowledgebase

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TravelRec.

Hi DJ!

News: I´ve figured out that on my Audigy (SB0090) the CD-In Socket is not grounded, so the 2 pins in the middle are left free. So if you connect a shielded cable there, the shield is really useless. So either you have to ground the pins manually by soldering a little bridge from back of the card to them or you have to get the ground from the AUX connector. This may be done by Creative to avoid ground loop effect between CD-Rom-Drive (on computer´s ground) and the separate analog ground plane on the card. Can you confirm this on your card or other models?


Greetings!

TravelRec.

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dj_stick

my card is the SB016x… the shielded cable had a 20dB lower noise floor than without… perhaps when i switched cables i swapped between CD_IN and AUX_IN…

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TravelRec.

Yes, but...

What´s with the pins on CD-In - are they free or just grounded on your card?

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dj_stick

i shall check on my card when i have the time… perhaps in an hour or so

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TravelRec.

Yeah, dont care!

I only want to know whether this is done on most card types or only on some models. If some users follow your project and only connect some adapter cable on CD-In - they will get worse results without a ground .

Greetings!

TravelRec.

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Nappylady

The ground connections on SB0160, SB0220, and SB0100 are all lifted! The nearest available ground comes from the Aux in, as you said. It seems to me that this is Creative's policy.

There is something odd about the ground pins for Aux on the SB0220. One pin is connected straight to the ground plane; the other is connected to a trace and runs off someplace... I've no idea what this means, probably nothing.

Doug W

I can check my SB0090 tonight.

TravelRec.

Hi!

Nice to know! Thank you for your research ! Maybe this fact should be added in knowledgebase or FAQ or something like that.

Greetings!

TravelRec.

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Doug W

Well, not many true grounds out there:


CD_IN pins from left to right
(resistance to ground)

SB0090
(1) 22k ohms, (2) 22k ohms, (3) 22k ohms, (4) 22k ohms

CT4830 (1)
(1) 50k ohms, (2) 50k ohms, (3) 50k ohms, (4) INFINITE

CT4830 (2)
(1) 50k ohms, (2) 50k ohms, (3) 50k ohms, (4) 50k ohms

CT4780
(1) 50k ohms, (2) 50k ohms, (3) 50k ohms, (4) 50k ohms

CT4870
(1) 14k ohms, (2) 7k ohms, (3) 4.5k ohms, (4) 14k ohms

CT4520 AWE 64
(1) 50k ohms, (2) 15k ohms, (3) 15k ohms, (4) 50k ohms

Yamaha XG YMF724E-V
(1) 3.5k ohms, (2) 300k ohms, (3) 3.5k ohms, (4) 3.5k ohms

CT1600 Sound Blaster Pro 2
(1) 15k ohms, (2) 12.5k ohms, (3) 15k ohms, (4) 34k ohms

AD1848JP Analog Devices Sound Port
(1) 10.5k ohms, ***(2) 0.0k ohms***, (3) 10k

Zoltrix Sound Card Audio Plus (8 Bit)
(1) 22k ohms, ***(2) 0.0k ohms***, (3) 22k ohms, ***(4) 0.0k ohms***

TravelRec.

Hmm,

very strange values sometimes, what was your reference ground? Computer chassis? Some cards have an extra "analog" ground area that is lifted from chassis ground to avoid ground loops, try to use a ground of line in socket or similar to use as reference.

Thanks anyway!

TravelRec.

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Doug W

Rechecked a few of those values using differnet ground spots on the card. Line in gnd, as you suggested, Aud_ex ground pin 3, metal of sound card etc.--same values.

Have you found different resistance values?

Doug