Sound card Dac.

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12-19-2009, 08:28
kiyoukan

Sound card Dac.

I am making a sound card dac but i do not wish to go usb.
http://www.semox.de/wordpress/wp-con...6/img_0179.jpg
That is my card (My camera sucks, so i found it on google)
I have seen only mods of the same usb style dac. Are there any instructions or advice for doing it on a pci style card?
Things to look for points to solder....
I also want to run the amp and galvos of the cpus power supply.
http://www.newegg.com/Product/Produc...82E16811154094
This is my case, notice the nice handle.:D
I plan on running everything even the galvos inside the case. The bottom and back side of the case are going to be reinforced to add stability.
All things will be tec cooled along with any vents on the machine having dust filters.
I am looking for any advice in moding this card into a very nice and successful dac along with what i might need to make a amp that does not need the 5 to 9 converter.
12-19-2009, 13:31
drlava

There are two important things to look for when choosing a sound card DAC - driver compatiblity and output quality. The audio card driver must be able to output audio data in an unmodified and clean way, and when no wave device is playing the driver should zero the output. The output of the audio card should have minimal hiss and computer noise - in other words the audio card should be well regulated, usually with a dedicated on-board regulator for the analog section. If it doesn't have this, if you know what you are doing it can be added.

The modification you will have to do to the card is simply to pick off the audio singals before the DC blocking capacitors (those small cylinders on the board.) You will need to use a multimeter and trace the signal path back from the audio output to one of the capacitor and note which channel is which. Not sure whether that sound blaster will be ok, feel free to post how well it works for you, for reference to people in the future.
12-19-2009, 18:05
kiyoukan

Okay that sounds easy enough just time consuming.
Okay and for the amp for my galvos any advice on making them run off the cpu power supply?
The ones i have seen only seem to run off usb powered.
Also anyone who has any experience with going a similar route would be very help full.
12-19-2009, 18:25
300EVIL

Quote:

Originally Posted by kiyoukan

Okay and for the amp for my galvos any advice on making them run off the cpu power supply?

I don't think that will work as "Most" ATX power supplies have a low current -12V supply. Besides Scanner amps typically run in the 15-24V range.

Quote:

Originally Posted by kiyoukan

The ones i have seen only seem to run off usb powered.

You cannot run galvos off of USB the standard is 5V @ around 500mA. Not going to happen.
12-19-2009, 20:36
kiyoukan

I have psu that can be modded to put out 24v. there is a -12 and a +12 i can also mix it to get 15.3v And it will still work with the cpu
12-20-2009, 00:28
shrad

the better option would be to run two DC/DC converters off the 12V line, which supplies the higher current in an ATX power supply, to get +24 and -24

if you go the internal sound card way, it might be a good idea to put a metallic shield over the analog part of the card (like a copper foil soldered on copper walls, themselves soldered to the analog ground plane

if using an ATX power supply to feed galvos, be sure to add correct decoupling capacitors otherwise galvos will pick switching noise from the power lines, which is BAD for them
12-20-2009, 06:45
kiyoukan

Well just to tell every one that case does not come with a psu. i have many lying spare around the house so i don't much know what one i am going to use.
So i am a bit confused. why do i need the DC/DC converters?
A psu with a little rewiring can be made into 24v Or is mixing the wire worse and would be just safer to use the dc/dc converters?
12-20-2009, 09:41
300EVIL

Quote:

Originally Posted by shrad

the better option would be to run two DC/DC converters off the 12V line, which supplies the higher current in an ATX power supply, to get +24 and -24

Sure, that would be a good way to go but something tells me this guy doesn't want to spend another $200.

Quote:

Originally Posted by kiyoukan

Well just to tell every one that case does not come with a psu. i have many lying spare around the house so i don't much know what one i am going to use.
So i am a bit confused. why do i need the DC/DC converters?
A psu with a little rewiring can be made into 24v Or is mixing the wire worse and would be just safer to use the dc/dc converters?

First off,,, what galvos are you getting?? Most galvo sets come with a power supply. You could wire the input on it to turn on when you switch on your PC with a relay.

If you start messing with the ATX PS, how will that affect the power requirements of your motherboard?

This is what you need... A 15-24V DUAL power supply. That's 1 NEGATIVE 15-24V, one ground and one POSITIVE 15-24V.

Again,, Find out what galvos you are getting. Figure out the power requirements, Voltage and Current Draw, then you can figure out how to power it.
12-20-2009, 11:35
kiyoukan

Okay thanks yeah i think it would be a lot better just to use 2 power supplys and just rig the second one up for when the psu wake up signal also will power up the second power supply. Saves a lot of headaches. I will have to do a bit more modding of the case to get all of this to fit but that is no problem.
The smallest psu i have lying around is a 500w and the comp going in there ran off a 250w, so i think there would be enough spare power to run the setup but no point reinventing the wheel. i will just use the supplied power supply.