Have done that, no change with or without the led. The missing board should be here in a day or two, maybe that might make a difference.
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What is the function of those dip switches, or filters?
How dose effect the sound? mine boars sounds harsh ...
Hi,like most owner of this Weiliang (AK4495 + AK4118 V.1.1) board, I was wondering what those dip switches function was. As it was difficult to follow the tracks on the PCB, I unsoldered the dip switch and discovered a design mistake: the PCB is designed to receive two jumpers, not a dual dip switch. If you look at the photos, you will notice that the right dip switch is short circuited by a track (which is tied to Vdd : High Level), you’ll also notice the two soldering hole of the left dip switch are both tied to resistors (pull down resistors) .That means the two dip switches are useless. The switches (or jumper) have to be installed first one: between hole identified 1 and 2, and second one: between the two other soldering hole.
According to AK4495 datasheet, on this board, the 4495 is running in parallel mode (pin 12 PSN is High) then the digital output filter configuration is determined by the pins 5 (SSLOW for Super Slow), 7 (SD for Short Delay) and 8 (SLOW). Pin 8 is tied to the soldering hole number 2, thus the jumper closest the 4495 is SLOW. Pin 7 is tied to the other jumper, wich is SD. Surprisingly pin 5 SSLOW is tied to Vdd (High) that means the filter is aimed at operating at slower sampling frequencies as described in page 28 of the datasheet which describe digital filter setup in parallel mode:
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SD SLOW Mode
L L Sharp roll-off filter
L H Slow roll-off filter
H L Short delay Sharp roll-off filter (default)
H H Short delay Slow roll-off filter
The AK4495S/95 can be operated on a slower sampling frequency. This mode is available when the SSLOW pin = “H”.
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This SSLOW mode is not described at all in the datasheet and all frequency graphs and filter response measurements graphs are made with SSLOW set to Low, not High. This raise two questions (is there any Asahi Kaisei engineer reading this posts?!) what’s the function of SSLOW and associated consequences on performance?, and why the designer of this board designer choose to use SSLOW mode ? What will I do soon: plug SD and SLOW to the Arduino I use on top of the board and maybe unsolder pin 5 in order to tie it to ground.
According the previous table the current and unmodifiable (without soldering iron) setup of the board AK4495 digital filter is: Sharp-roll filter with Super slow mode.
To end, most of the AK4495 board I’ve seen on ebay, aliexpress, etc (there’re many variants) have a very close PCB layout and I’ve always seen the dual red dipswitch close to the AK4495, the self, the pull down resistors,…Do they all share the same design flaw ?
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Mine has been supplied by the DAC board vendor, this his an seven pin one, available in many Internet shops for around 45$. It works, but some capacitors are not the right ones (electrolytic rather than low ESR according to the datasheets) and picking the right driver was difficult. Now, it works fine.
If this board is intended to be used with the 4495 DAC, you should notice that the Weilliang board AK44995+AK4118 V.1.1 doesn't support DSD. As said in my previous post the 4495 is operating in parallel control mode, this mode disable DSD support.
If this board is intended to be used with the 4495 DAC, you should notice that the Weilliang board AK44995+AK4118 V.1.1 doesn't support DSD. As said in my previous post the 4495 is operating in parallel control mode, this mode disable DSD support.
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