Thanks for the input flowerpot. The difficulty is that I wasn't getting the pops previously but then I was using a 40KHz LPF, now 80KHz, I was using HQP 3.11, now 3.12, I was using a different NAA platform and Linux distro....
In theory, the buffering on the JLSounds board should delay the signal long enough for the mute relay to have activated? The Amanero doesn't have that I believe.
Version 3.12 of HQP has been tweaked for the integration with Roon and I wonder if that has resulted in some different behaviour with the codec change trigger timing?
I'm wondering if, with the mute relay, we are treating the symptoms rather than the illness; perhaps the player software could be modified to stop the transient pop events occurring with a soft start/stop function - soft only means wind up or down over a few milisecs rather than instantaneous? I don't know enough about this stuff.
In theory, the buffering on the JLSounds board should delay the signal long enough for the mute relay to have activated? The Amanero doesn't have that I believe.
Version 3.12 of HQP has been tweaked for the integration with Roon and I wonder if that has resulted in some different behaviour with the codec change trigger timing?
I'm wondering if, with the mute relay, we are treating the symptoms rather than the illness; perhaps the player software could be modified to stop the transient pop events occurring with a soft start/stop function - soft only means wind up or down over a few milisecs rather than instantaneous? I don't know enough about this stuff.
Here the antibump.
Antibump per bulgaro e affini: finalmente è nato e funziona!
Antibump per bulgaro e affini: finalmente è nato e funziona!
An externally hosted image should be here but it was not working when we last tested it.
giusta.jpg)
Hi, I'm Fabio from Italy, At first thanks to Ray to have add me to the group buy.
For the bump, Leon 77 have posted the circuit that I have used with the nodac in windows system, hqplayer and naa with jplay. The original design had bump on play but not in stop, after I add a ne555 and the bump in play is off. My friend Daniele have also used the LME49710 filter board design from jlsounds for the part of this circuit and it is ok. All two circuits are ok for nodac. Bye, Fabio
For the bump, Leon 77 have posted the circuit that I have used with the nodac in windows system, hqplayer and naa with jplay. The original design had bump on play but not in stop, after I add a ne555 and the bump in play is off. My friend Daniele have also used the LME49710 filter board design from jlsounds for the part of this circuit and it is ok. All two circuits are ok for nodac. Bye, Fabio
I've been at play again. I reverted to HQP version 3.10 to check the mush noise issue out; it is still there on 3.10 with the digital volume control engaged but disappears when I return to Direct DSD mode. I will have to wait for Jussi to reply to my observations.
ignoring the issues for a moment, I'm still surprised at just how good this DSD playback approach sounds so it's well worth persevering.
On the pop issue, I've been trying to get my head around it because I perceive an inconsistency. The mute relay's default (un-energised) position is to short the output to ground. There is a pop when you press start, which means that the relay is activated too quickly (the relay must be energised otherwise the pop would be lost to ground). On the other hand, there is a pop when stop is pressed, which means the relay is deactivated too slowly (again, the relay must still be energised otherwise the pop would be lost to ground). I can see the delay introduced into the mute circuit posted by leon77 could help when start is pressed but not how an additional delay can help with the stop pop. What am I missing?
ignoring the issues for a moment, I'm still surprised at just how good this DSD playback approach sounds so it's well worth persevering.
On the pop issue, I've been trying to get my head around it because I perceive an inconsistency. The mute relay's default (un-energised) position is to short the output to ground. There is a pop when you press start, which means that the relay is activated too quickly (the relay must be energised otherwise the pop would be lost to ground). On the other hand, there is a pop when stop is pressed, which means the relay is deactivated too slowly (again, the relay must still be energised otherwise the pop would be lost to ground). I can see the delay introduced into the mute circuit posted by leon77 could help when start is pressed but not how an additional delay can help with the stop pop. What am I missing?
I can help with the comparison to a Soekris. But I was planning on building a flip-flop board. It would be more fair if I built a SE one. Perhaps I'll get a SE board as well.
I dun think there is a way to design a mute circuit to tackle both start and stop... It's either u are faster at the start and slower at the stop or vice visa depending how the mute circuit... Like I say it's best from the software player side to actually fade off during stop(turning down the digital volume real quick maybe) before stopping... And fade in(turning up the digital volume real quick to the pre set point by the user maybe) during start.... Anyway I'm not losing sleep over this... I just leave with it and enjoy the music
OK I finished wiring up the pre-amp. See picture below. As well as wiring up the selector switches, I have put in a few filter caps as suggested by Emilio. There are caps on the regulators, and I have also put caps right on the input pin of the JLSounds board. I only wish I had bought a wider enclosure - it got a bit tight soldering the switch that is next to the no-DAC components/wiring.
I'm now listening to the no-DAC using Ubuntu OS, HQPlayer 3.12 upsampling to DSD256. Observations so far.
1. There is NO noise. Or no noise that I can hear from my couch. The prototype no-DAC, that was sitting out in free air, suffered from various hf noise and whooshing type sounds. I think that it was picking up lots of interference. Now I have enclosed it completely in a box, and put bypass caps on all the power inputs - no noise.
2. Only pops I get are when I change sampling fequency (I upsample to 11.3 MHz for 44.1kHz family including SACD, I upsample to 12.3 MHz for 48kHz family). Even then the pop is innocuous. There are NO pops when tracks start and stop, or when I hit the next track button or stop button.
NOTE - I haven't tested with Windows10 just yet, but last time I used windows there were lots of pops as described by Ray. But Ubuntu seems fine - note that I am using Jussi's kernel 3.33.0.55 (available via the signalyst.com website). Ubuntu still doesn't support native DSD (only DSD as DOP) but Jussi's modified kernel will support native DSD up to DSD256.
3. As requested by Emilio, I have measured the output of my no-DAC. I created a 440Hz, 0dB test signal using Audacity as a 16 bit wav file. Upsampling to DSD256 via HQPlayer, I measured 1.55V at the output of the transformer.
4. And the sound is - absolutely lovely. PCM files, from 44.1k to 192k, and DSD files are handled with aplomb. I'm still a vinyl man at heart, but most vinyl these days is cut from hi res digital files. I reckon that those files will sound better if I buy them from HDTracks and play them via the no-DAC, rather than buying them encoded onto vinyl, and decoding with my Lenco. I will still listen to my older (analog) LPs on the Lenco, but for now I am pretty happy.
Regards, Hazard
I'm now listening to the no-DAC using Ubuntu OS, HQPlayer 3.12 upsampling to DSD256. Observations so far.
1. There is NO noise. Or no noise that I can hear from my couch. The prototype no-DAC, that was sitting out in free air, suffered from various hf noise and whooshing type sounds. I think that it was picking up lots of interference. Now I have enclosed it completely in a box, and put bypass caps on all the power inputs - no noise
.2. Only pops I get are when I change sampling fequency (I upsample to 11.3 MHz for 44.1kHz family including SACD, I upsample to 12.3 MHz for 48kHz family). Even then the pop is innocuous. There are NO pops when tracks start and stop, or when I hit the next track button or stop button
.NOTE - I haven't tested with Windows10 just yet, but last time I used windows there were lots of pops as described by Ray. But Ubuntu seems fine - note that I am using Jussi's kernel 3.33.0.55 (available via the signalyst.com website). Ubuntu still doesn't support native DSD (only DSD as DOP) but Jussi's modified kernel will support native DSD up to DSD256.
3. As requested by Emilio, I have measured the output of my no-DAC. I created a 440Hz, 0dB test signal using Audacity as a 16 bit wav file. Upsampling to DSD256 via HQPlayer, I measured 1.55V at the output of the transformer.
4. And the sound is - absolutely lovely. PCM files, from 44.1k to 192k, and DSD files are handled with aplomb. I'm still a vinyl man at heart, but most vinyl these days is cut from hi res digital files. I reckon that those files will sound better if I buy them from HDTracks and play them via the no-DAC, rather than buying them encoded onto vinyl, and decoding with my Lenco. I will still listen to my older (analog) LPs on the Lenco, but for now I am pretty happy.
Regards, Hazard
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Mick, the JG buffer sounds very good and I recommend giving it a try. The JLSounds buffer I'm using is great value for money too.
It's difficult to be precise given the mush noise issue I'm experiencing with HQPlayer's volume control (I have to use it with the flip-flop/BCF build as it has no volume control of its own) but I don't think there is much between my two projects sound quality.
Ray
Thanks Fabio. I used google translator to get an idea of the discussion at the link Leon posted. One option would be to modify my boards to include the delay that you've designed - would that be OK with you?
Hi Jesper. I'm not getting any pops or clicks during playback, just with Start and Stop. I am planning to have a look at Jussi's design to see what can be learned from it.
Ray