General question regarding filters on the dam. I know the dam doesn’t do any dithering but do the filters do anything in the way of noise shaping? Again I assume the dam filters don’t shape noise in the audible spectrum in the way of Lipshitz or Wannamaker? (In the audible spectrum, I’m not referring to aliasing above Nyquist/2).
There are two reasons that there is no DSD support.
First all my filters are still in development stage, so it’s for me more convenient to work with files that are more clean(short).
Second I not investigate yet how they work and how they connected to soren filtering structure , I have more complex approach and I treat all filters on every stage as one.
Evidently I’m not hiting target for wider mainstream with my last filters soo we have long road ahead 😊
In final realse for sure I will include DSD.
I haven’t tried your latest set as I thought they didn’t fully attenuate at 22050 Hz and I like to follow sampling theorem with my high bandwidth, solid state amp.
They are full attenuated as all my filters over 22050Hz
But instead sloop there is climb to 20kHz c.a. 1.5db and a lot of harmonics, they can reach c.a. 5%
Total Dac has that with FIR on/off function 😊
But still I thing I’m not hiting target with tonal balance so try it and let me know but probably I have to prepare something different.
But instead sloop there is climb to 20kHz c.a. 1.5db and a lot of harmonics, they can reach c.a. 5%
Total Dac has that with FIR on/off function 😊
But still I thing I’m not hiting target with tonal balance so try it and let me know but probably I have to prepare something different.
Finally readjusted allpass filter for hopefully satisfy wider group of people. It’s based on one of my early filter, so should be ok but verification is needed.
Some more explanation about allga filters family.
F4 to F6 filters stacks are made identically just with small change in FIR2 stage filter which is new 64 coefficient filter.This small difference allow to make adjustment of sound presentation according to preference.
Second thing that is special in allga family is magnified distortion adjustment with volume. If we set 0db on dac we could get over 5% THD. Lowering volume to c.a -6db on dac almost cancel that effect, so we have 0 to -6 db to adjust harmonics to preferred level.
There is FR with elevated high frequency ca 1.5db
F7 filter is NOS/NewNOS stack for “classical” presentation(volume level works as usually🙂
Anti aliasing for all with IIR filters.
Some more explanation about allga filters family.
F4 to F6 filters stacks are made identically just with small change in FIR2 stage filter which is new 64 coefficient filter.This small difference allow to make adjustment of sound presentation according to preference.
Second thing that is special in allga family is magnified distortion adjustment with volume. If we set 0db on dac we could get over 5% THD. Lowering volume to c.a -6db on dac almost cancel that effect, so we have 0 to -6 db to adjust harmonics to preferred level.
There is FR with elevated high frequency ca 1.5db
F7 filter is NOS/NewNOS stack for “classical” presentation(volume level works as usually🙂
Anti aliasing for all with IIR filters.
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Thanks for these extensive graphs, that's very informative! 
Now genuinely curious and not at all intended as inflammatory, I'm wondering what your design goals are for F4-F6? From a measurement standpoint you could say that NewNOS has lower THD even when comparing F7 at 0 dB to F6 at -6 dB. Moreover, the highest spikes are odd harmonics which is generally not what you want.
I've yet to listen to them, and I will, but as you know I like to look from both the objectivist and subjectivist standpoint (call me a "rational" audiophile 🙂)
(Also I'm just surprised how low THD and harmonics are on NewNOS!)
Now genuinely curious and not at all intended as inflammatory, I'm wondering what your design goals are for F4-F6? From a measurement standpoint you could say that NewNOS has lower THD even when comparing F7 at 0 dB to F6 at -6 dB. Moreover, the highest spikes are odd harmonics which is generally not what you want.
I've yet to listen to them, and I will, but as you know I like to look from both the objectivist and subjectivist standpoint (call me a "rational" audiophile 🙂)
(Also I'm just surprised how low THD and harmonics are on NewNOS!)
F4-F6 filters are designed to make music more alive, present. I believe that harmonics and correct tonal balance are the way to do that. Because we are on different systems and have sometimes completely different preferences I want to create some flexibility.
So now anyone can easily confront pure distortion free filter vs “as much you can handle” regulated distortion filter 😊
F7 NOS/NewNOS was measured from hybrid tube preamp out so it could be much better on ss. It’s normal for NOS.
So now anyone can easily confront pure distortion free filter vs “as much you can handle” regulated distortion filter 😊
F7 NOS/NewNOS was measured from hybrid tube preamp out so it could be much better on ss. It’s normal for NOS.
Is it so normal? Archimago's Musings: NOS vs. Digital Filtering DACs: Exploring filtering turned off, implications, fidelity and subjective audibility. (Recent BorderPatrol DAC chatter...)
Normally non-linearities from NOS square steps cause all sorts of distortion.
Normally non-linearities from NOS square steps cause all sorts of distortion.
Maybe not so common, but NOS has the best impulse response, so it’s normal. All other problems can be solved by IIR to acceptable level in my case and Soekris Sign Magnitude Discrete R-2R architecture which allow NOS to be civilized. Look at Denafrips Terminator and his NOS, they are exploring this area too.
Thanks. Sorry for not having tested them yet. In my free time I'm pretty occupied finishing some contributions to librespot. Then there's some holidays coming up. But rest assured I'm with you here, please be patient 🙂
Opposite to last production this filters set is designed as clean as possible. So now the biggest source of distortion is my amplifier power supply 😊
I don’t have fancy test equipment and my dam1021 is 0.05% version. Filters stack structure is similar to allgama with one exception F6 filter on first stage is now C128DP.
Some improvement in tonal balance are implemented.
I don’t have fancy test equipment and my dam1021 is 0.05% version. Filters stack structure is similar to allgama with one exception F6 filter on first stage is now C128DP.
Some improvement in tonal balance are implemented.
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Thanks, I'm currently trying F4 and liking what I'm hearing. What is allgama by the way? And is it possible to get more gain?
Thanks. Allgama(allga) is filters structure based on NOS on first stage and 64 coefficients on second stage (FIR2) introduced in previous filters set. Unfortunately more gain is not possible.
Yes. All my filters sets use IIRs as anti-aliasing, anti-imaging filters. They are common for all filters stacks and have the biggest influence on overall performance.
