Filter brewing for the Soekris R2R

Thanks, but I don't know.
I have to play pure DC samples without interpolations and without DC high pass filter.
In other words when the DAC receives binary 192kHz/24 bit 0100 0000 0000 0000 0000 0000 it should play exactly the original word, in this case half the maximum peak DC output (around 1Vdc).

Someone can tell if it will work?

I have asked the designer but he told me that he supports factory filter only.

Can anyone tell me how to play bit perfect with the DAM1021?
 
This is a basic filter set based on the previous clean3. What makes one file different from the others is the all pass filter used to manipulate the presentation from a laid back (501) to forward presentation (340). So you can choose it according to your preferences. The steepness is quite rough, but it allows you to identify the differences quite easily.
 

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  • Clear3_filters_set.zip
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This filters set is an attempt to bring better pseudo NOS to Soekris R2R dacs family.
First two filter F4 and F5 are more classical approach with zero padding on first stage and band limiting on second.
The F6 and F7 filters are a slightly different approach with better results from my perspective.
There is no IIR and even deemphasis just pure FIRs
 

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  • BPNOS_F7_300Hz_Sq_192kHz.png
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  • BPNOS_F4_300Hz_Sq_192kHz.png
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  • BPNOS_F7 1kHz Sine_192kHz.png
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  • BPNOS_F4 1kHz Sine_192kHz.png
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  • BPNOS__F7_IR_192kHz.png
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  • BPNOS__F4_IR_192kHz.png
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  • 1021filt_BPNOS.zip
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I will be happy if you try them and then share your comments especially because you are on headphones. I wonder if you will be able to hear small ripples that we can observe on F4/F5 filters as anoying or fatiguing after sometime.

Well, these certainly do not disappoint! No grain or rasp like in NewNOS.

First impressions after a few hours of listening is that F4 and F5 sound fuller and more intimate (forward) than F6 and F7. Those two sets are easily discernible, and every time I find myself more attracted to F4/F5. (I'm using my auditioning script that randomly switches every 30 seconds in the background, while I'm doing other stuff on my computer.)

For further impressions and certainly fatigue I'll have to listen some more.
 
w.r.t. RS232 on the dam1021 I think you're right. Manual page 10:
http://www.soekris.dk/download/dam1021/dam1021 user manual 20151005.pdf

Note that I'm using a dam1121 and not a dam1021.

@andrea, please don't take this the wrong way but I am a bit surprised that you've always run the stock filters, given your critique and even listening tests with friends over at the other main thread. I understand, of course, that this is entirely different from the clock. Still, I hope you get this sorted because the filters here offer a lot more musical enjoyment over the factory ones.
 
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Well, these certainly do not disappoint! No grain or rasp like in NewNOS.

First impressions after a few hours of listening is that F4 and F5 sound fuller and more intimate (forward) than F6 and F7. Those two sets are easily discernible, and every time I find myself more attracted to F4/F5. (I'm using my auditioning script that randomly switches every 30 seconds in the background, while I'm doing other stuff on my computer.)

For further impressions and certainly fatigue I'll have to listen some more.

Thanks.
I wonder if you have possibility to directly compare to real NOS Dac.
 
w.r.t. RS232 on the dam1021 I think you're right. Manual page 10:
http://www.soekris.dk/download/dam1021/dam1021 user manual 20151005.pdf

Note that I'm using a dam1121 and not a dam1021.

@andrea, please don't take this the wrong way but I am a bit surprised that you've always run the stock filters, given your critique and even listening tests with friends over at the other main thread. I understand, of course, that this is entirely different from the clock. Still, I hope you get this sorted because the filters here offer a lot more musical enjoyment over the factory ones.

I have listened to the DAM1021 as it comes from the factory, I would expect the device comes configured at its best.

And as you can see I have some difficult to update the filter.
I also have asked for the help from the designer in the main thread with no success.
So I cannot update the filter.