Improving Digital Output of Juli@ soundcard by Cleaning its Power - promethk - Computer Audio Asylum

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Music servers and other computer based digital audio technologies.

Improving Digital Output of Juli@ soundcard by Cleaning its Power

Reading immate's observations of the effects of bus speed and ram timings on sound quality, which quite naturally suggest noisy power as the culprit. I took a look at the components of Juli@ soundcard digital section and found the following.

The three main components are all powered by 3.3V, namely:
VIA Envy24HT controller
Xilinx XC9536XL CPLD
AK4114 digital audo interface transceiver 32kHz - 192 kHz

There is a low dropout voltage regulator MT1117-3.3A0639F, providing 3.3 V to all the components above from an input voltage of 5V, suggesting to focus on both 3.3V and 5V.

To suppress noise, the best tweak would be to solder high quality caps directly on the power pin of the three chips above. Though the soldering of such tiny SMD components' legs are quite beyond me. The second best would be to solder quality caps on the voltage regulator which could be workable. I take the easy route without soldering and use connection pins of the digital board to the analogue board for mounting the coupling capacitors.

After a bit of research and toying with the multimeter, I figure that the group of 20pins seems to be digital data. The group of 10pins should be power distribution to the analogue board containing 12V, -12V, 5V and 3.3V and several grounds.

I use screw-in type power connectors to connect a blackgate FK 470uF parallel with a multicap RTX 0.1uF to pin 2 (5V) and pin 5 (ground). The blackgate was originally "pluged" into the 12V supply to filter the noise there.

Results:
The traces of glare or tightness very noticible in the voices associated with running the system bus at 200Mhz are reduced/eliminated. There are also other big improvements but I would not go further here as they may as well be due to gradual break-in of the recently built balanced transformer for the DAC.

Disclaimer: I don't have any professional experience in electronics, feel free to correct me!

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Topic - Improving Digital Output of Juli@ soundcard by Cleaning its Power - promethk 12:04:35 08/18/08 (6)

RE: Improving Digital Output of Juli@ soundcard by Cleaning its Power - theob 09:48:04 01/24/11 (0)

RE: Improving Digital Output of Juli@ soundcard by Cleaning its Power - theob 04:29:30 01/26/11 (0)

RE: Improving Digital Output of Juli@ soundcard by Cleaning its Power - drmike 10:09:45 01/28/11 (0)

RE: Improving Digital Output of Juli@ soundcard by Cleaning its Power - theob 12:10:30 01/28/11 (0)

RE: Improving Digital Output of Juli@ soundcard by Cleaning its Power - drmike 14:07:33 01/28/11 (0)

RE: Improving Digital Output of Juli@ soundcard by Cleaning its Power - theob 16:25:38 01/28/11 (0)

RE: Improving Digital Output of Juli@ soundcard by Cleaning its Power - Jolida 02:26:14 01/18/11 (0)

RE: Improving Digital Output of Juli@ soundcard by Cleaning its Power - theob 05:00:59 01/18/11 (0)

Could you be more specific as to which pins? - rickmcinnis@dogwoodfabrics.com 10:05:00 08/19/08 (3)

RE: Could you be more specific as to which pins? - promethk 10:30:38 08/19/08 (2)

Thanks - rickmcinnis@dogwoodfabrics.com 12:24:30 08/19/08 (1)

RE: Thanks - promethk 19:45:20 08/19/08 (0)

Have you tried lower CPU voltages? - cics 03:06:32 08/19/08 (1)

RE: Have you tried lower CPU voltages? - promethk 07:36:56 08/19/08 (0)

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