Filter brewing for the Soekris R2R

Not really sure how I can compensate the volume for certain sample rates...
Yes, as I said, it's going to be a long time test, but so big sound different makes it kinda...disturbing, as listening 88.2 and 96khz files requires noticeably big change in volume level and if I'm gonna forger to drop it down, moving to the songs with other sample rates - that's going to be a hard punch in my ears)
 

TNT

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Joined 2003
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NOS (44,48) in the pack looks like:

dam1021,44100,8,1007,8,6.4
07 NOS FIR1, 44.1 Khz.

dam1021,48000,8,7,8,6.4
07 NOS FIR1, 48 Khz.

0.125
0.125
0.125
0.125
0.125
0.125
0.125
0.125

dam1021,88200,4,1007,4,3.2
07 NOS FIR1, 88.2 Khz.

dam1021,96000,4,7,4,3.2
07 NOS FIR1, 96 Khz.

0.25
0.25
0.25
0.25

dam1021,176400,2,1007,2,1.6
07 NOS FIR1, 176.4 Khz.

dam1021,192000,2,7,2,1.6
07 NOS FIR1, 192 Khz.

0.5
0.5

dam1021,352800,1,4,1,0.999999995
07 NOS FIR1, 352.8 Khz.

1.0

dam1021,384000,1,4,1,0.999999995
07 NOS FIR1, 384 Khz.

1.0


dam1021,352800,8,1011,8,7.999999995
11 NOS FIR2, 352.8 Khz.

dam1021,384000,8,11,8,7.999999995
11 NOS FIR2, 384 Khz.

0.125
0.125
0.125
0.125
0.125
0.125
0.125
0.125

//
 
Last edited:

TNT

Member
Joined 2003
Paid Member
Sample rate?

If you run with bank 7 you get NOS for all different Fs, If you run bank 4 you get actually a bit differences between 44/48 and other because I have implemented 3 dB interover margin in my filters - someone "complained" about that earlier.

Use an other pack :)

//
 

TNT

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Joined 2003
Paid Member
I thought by design/architecture the Soekris DAC is an oversampling DAC (x64)? Therefore impossible to NOS.

Isn’t the NOS filter fake? It should just be called “passthrough filter” to avoid confusion.

Or maybe I am totally wrong...

This is my understanding also. Its not like the conversion process ges on at 44100 times a second - its still done at 2,8 Mhz.

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This is my understanding also. Its not like the conversion process ges on at 44100 times a second - its still done at 2,8 Mhz.

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I've read about this case some controversial opinions, so I'm not sure is the NOS filter makes 1421 true NOS dac or it's kinda simulates it? No matter of true, for me the most important thing about filter is - how the dac sounds with it. So, if I'll found the performance of NOS filter the best sounding to me, from all if the rest - I don't really care about - does it really make 1421 true NOS dac or not)
 
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Joined 2019
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I use Audirvana for streaming to my Soekris 1321 and I've been playing around with its upsampling feature. The Soekris has the latest 1.21 filters, all of which I like. My question is how does the onboard Soekris filtering interact with the filtering that's happening with the upsampling? FWIW, I lean towards the soft butterworth on the Soekris, which I believe is the 'default' filter.

Any suggestions on settings for the upsampling filtering? Screenshot of options attached.
 

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TNT

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Joined 2003
Paid Member
If you feed it 384 kbps, the first set of filters are no more in play - only FIR2, the last OS stage is active - it is also a filter. If lower Fs, the filters are doing there thing as usual. If you upsample and also filter you get double filtering I suppose.

I suppose the Default is Bank 4 or Linear. I doubt that is Butterworth.

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