crenca Posted June 26, 2017 Share Posted June 26, 2017 21 hours ago, firedog said: So you are saying that the claimed "deblurring" is simply the use of minimum phase filter, nothing else? Sure seems that way to me. The only caveat is that MQA does claim magic at the ADC side of things - but as a practical and technical matter on the consumer side (software/hardware playback) "deblurring" appears synonymous with minimum phase filtering. Hey MQA, if it is not all $voodoo$, show us the math! Link to comment
Fokus Posted June 26, 2017 Share Posted June 26, 2017 Sorry guys, but no. MQA's deblurring is first and foremost the use of short, shallow, leaky anti-alias and anti-imaging filters during music production (downsampling from an ADC running at max rate to 2x rate for storage and distribution) and replay (upsampling to a particular DAC's max rate). That some or all of these filters are minimum phase is not that relevant, since the filters are so short. The rationale is to marry a 2x channel with a 4x or 8x or 16x or whatever x impulse response width. This has been spelled out in MQA literature from day one. On top of this, and for low rate original recordings, they have a patent for an all pass filter with a large group delay centered on the ADC's transition frequency. It is not clear if this filter is actually being used. MrMoM 1 Link to comment
Jud Posted June 26, 2017 Share Posted June 26, 2017 7 hours ago, Fokus said: Sorry guys, but no. MQA's deblurring is first and foremost the use of short, shallow, leaky anti-alias and anti-imaging filters during music production (downsampling from an ADC running at max rate to 2x rate for storage and distribution) and replay (upsampling to a particular DAC's max rate). That some or all of these filters are minimum phase is not that relevant, since the filters are so short. The rationale is to marry a 2x channel with a 4x or 8x or 16x or whatever x impulse response width. This has been spelled out in MQA literature from day one. On top of this, and for low rate original recordings, they have a patent for an all pass filter with a large group delay centered on the ADC's transition frequency. It is not clear if this filter is actually being used. If I'm understanding correctly, it doesn't matter much that with a minimum phase filter, time through the filter depends on frequency, because with the short filter that's being used, the time difference won't be much. Regarding the all pass filter: What might this be used for? To "correct" group delay in the opposite direction from the ADC? To add group delay and thus a feeling of depth? Unknown? One never knows, do one? - Fats Waller The fairest thing we can experience is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science. - Einstein Computer, Audirvana -> optical Ethernet to Fitlet3 -> Fibbr Alpha Optical USB -> iFi NEO iDSD DAC -> Apollon Audio 1ET400A Mini (Purifi based) -> Vandersteen 3A Signature. Link to comment
Fokus Posted June 26, 2017 Share Posted June 26, 2017 To literally move the preringing of the original filter to after the impulse. A bit bonkers. Link to comment
Jud Posted June 26, 2017 Share Posted June 26, 2017 2 hours ago, Fokus said: To literally move the preringing of the original filter to after the impulse. A bit bonkers. Ah, so "blurring" *after* the impulse is fine. One never knows, do one? - Fats Waller The fairest thing we can experience is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science. - Einstein Computer, Audirvana -> optical Ethernet to Fitlet3 -> Fibbr Alpha Optical USB -> iFi NEO iDSD DAC -> Apollon Audio 1ET400A Mini (Purifi based) -> Vandersteen 3A Signature. Link to comment
crenca Posted June 26, 2017 Share Posted June 26, 2017 3 hours ago, Fokus said: To literally move the preringing of the original filter to after the impulse. A bit bonkers. 44 minutes ago, Jud said: Ah, so "blurring" *after* the impulse is fine. which is what a min phase filter does no? Hey MQA, if it is not all $voodoo$, show us the math! Link to comment
Fokus Posted June 27, 2017 Share Posted June 27, 2017 14 hours ago, crenca said: which is what a min phase filter does no? Sort of. In our context of audio replay a Meridian-style minimum phase filter's treble rolloff attenuates the recording-side's anti-alias filter's ringing (pre and post), and imposes its own (post-only) ringing at a lower frequency. (Sidenote: an Ayre, or whomever, -style MP filter does not attenuate enough and does nearly bugger all for the original ringing, but that's another story.) The all-pass filter in MQA's patent does not attenuate anything, it only delays the signal at the original AA filter's transition frequency, literally moving that one's ringing around. Mind, I have no idea that this is actually being used on original low-rate recordings when preparing them for MQA. Link to comment
Jud Posted June 27, 2017 Share Posted June 27, 2017 5 hours ago, Fokus said: The all-pass filter in MQA's patent does not attenuate anything, it only delays the signal at the original AA filter's transition frequency, literally moving that one's ringing around. Fokus, you’re a marketing genius. ”MQA - Movin’ that ringin’ around.” One never knows, do one? - Fats Waller The fairest thing we can experience is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science. - Einstein Computer, Audirvana -> optical Ethernet to Fitlet3 -> Fibbr Alpha Optical USB -> iFi NEO iDSD DAC -> Apollon Audio 1ET400A Mini (Purifi based) -> Vandersteen 3A Signature. Link to comment
saintintn Posted June 27, 2017 Share Posted June 27, 2017 Good topic, guys. Hey, can you guys do a test for me? All my Tidal Masters albums give me the blue light in the DFR except for Coldplay Ghost Stories (Master version). It's been consistently that way. Thanks! Link to comment
citsur86 Posted June 27, 2017 Share Posted June 27, 2017 Need some help. For some reason - only MQA tracks output volume from Tidal now using my Dragonfly Red. I have the Dragonfly Red in Tidal set to Use Exclusive Mode. I see the dragonfly red change colors from the dark magenta to green/orange when playing other bitrate music, and the song is playing (song progress is moving), but nothing is being ouptput to the headphones via the DFR. Anyone know what's going on? Using a Macbook Pro and I can see in Midi Audio settings that the bitrate is auto changing from 96,000Hz to 44,100Hz when the DFR is green. Can't get any sound though Link to comment
saintintn Posted June 27, 2017 Share Posted June 27, 2017 In Midi Audio, what is the Master Volume setting for the DFR? Might be at zero? Or the Tidal App is at zero. Otherwise, not sure. Link to comment
Wavelength Posted June 27, 2017 Share Posted June 27, 2017 2 hours ago, saintintn said: In Midi Audio, what is the Master Volume setting for the DFR? Might be at zero? Or the Tidal App is at zero. Otherwise, not sure. DragonFly enumerates with a dB scale. Therefore full output is 0 down to -64dB and then it mutes. Thanks, Gordon 2 hours ago, citsur86 said: Need some help. For some reason - only MQA tracks output volume from Tidal now using my Dragonfly Red. I have the Dragonfly Red in Tidal set to Use Exclusive Mode. I see the dragonfly red change colors from the dark magenta to green/orange when playing other bitrate music, and the song is playing (song progress is moving), but nothing is being ouptput to the headphones via the DFR. Anyone know what's going on? Using a Macbook Pro and I can see in Midi Audio settings that the bitrate is auto changing from 96,000Hz to 44,100Hz when the DFR is green. Can't get any sound though If you are using the 1.06 version of software on the DragonFly then you should contact Tidal support to see what might be the issue. It may not be volume, but you could check that by running Audio Midi (found in your utilities folder). It will show the actual volume setting of the DF at the time the song is running. You can also change it there... but I do know there was a bug in the Windows software so I would imagine one in the macOS as well. Either way you would be narrowing down the problem. Thanks, Gordon J. Gordon Rankin Wavelength Audio http://www.usbdacs.com/ http://www.wavelengthaudio.com/ http://www.guitar-engines.com/ Link to comment
Wavelength Posted June 27, 2017 Share Posted June 27, 2017 2 hours ago, saintintn said: Good topic, guys. Hey, can you guys do a test for me? All my Tidal Masters albums give me the blue light in the DFR except for Coldplay Ghost Stories (Master version). It's been consistently that way. Thanks! Do you have exclusive mode set in your Tidal configuration under DragonFly? Ghost Stories is 24/96 so your probably seeing magenta and not Purple which indicates MQA. Blue means 48K sample rate at 24bits. Thanks, Gordon J. Gordon Rankin Wavelength Audio http://www.usbdacs.com/ http://www.wavelengthaudio.com/ http://www.guitar-engines.com/ Link to comment
saintintn Posted June 27, 2017 Share Posted June 27, 2017 So, I can get the magenta by setting my Mac to play 24/96 via Midi Audio. But is that just Ghost Stories being upsampled from 16/44.1? How do I know that MQA is being properly decoded, in other words into true 24/96? I selected MQA passthrough, so the DFR should be the device decoding it. Link to comment
mansr Posted June 27, 2017 Share Posted June 27, 2017 1 minute ago, saintintn said: So, I can get the magenta by setting my Mac to play 24/96 via Midi Audio. But is that just Ghost Stories being upsampled from 16/44.1? How do I know that MQA is being properly decoded, in other words into true 24/96? I selected MQA passthrough, so the DFR should be the device decoding it. Passthrough doesn't work with the Dragonfly since it is only a renderer, not a full decoder. You need to enable the core decoding in Tidal or Audirvana. Link to comment
saintintn Posted June 27, 2017 Share Posted June 27, 2017 To test the theory, I set the Midi Audio to 16/44.1 on the DFR and played Another's Arms (Master). The light is green. When I unchecked Passthrough MQA and played it again, the DFR showed magenta. I have upgraded the DFR to the version that decodes MQA, but it doesn't appear to be doing it when I check the MQA Passthrough box. Link to comment
saintintn Posted June 27, 2017 Share Posted June 27, 2017 Gosh, so where exactly would you use the DFR for MQA? At what point in the chain, if you will? Link to comment
Fokus Posted June 28, 2017 Share Posted June 28, 2017 You need something doing the core decoding (= unfolding from 1x to 2x) first. AFAIK only Tidal, set up properly for doing this, applies. Link to comment
mansr Posted June 28, 2017 Share Posted June 28, 2017 2 hours ago, Fokus said: You need something doing the core decoding (= unfolding from 1x to 2x) first. AFAIK only Tidal, set up properly for doing this, applies. Audirvana also has that ability. Link to comment
Hierge Posted July 26, 2017 Share Posted July 26, 2017 Someone on CA once told me to shut up and listen. Enjoy the music. I have been listening to Tidal with the new firmware on a Black model. First noticed the bluish purple light which is new. The sound is really good. I put on my Sony MDR V6 headphones which expose everything including flaws. I listened to Led Zepplin III and Jethro Tull Aqualung on Tidal with the Master versions playing. Made sure to get the settings right on pass through and exclusive mode. I definitely hear things I've never heard on these tracks. I'm slowly acclimating my ears for the new sound, but so far it's definitely fantastic. I think that Gordon and Audioquest really did Dragonfly owners a HUGE service adding this support to our existing units for NO CHARGE!!! And all I read here is people hassling Gordon over technical issues. Just listen to the damn thing! I am so very happy and feel like Tidal is finally starting to get serious with their sound too adding Master Recordings. What I would like to say to Gordon or anyone from Audioquest is that I'm having some issues with Tidal recognizing the Dragonfly as being an MQA decoder. I had to reboot my system and jerry around with it to get the blue light to come back on with the Dragonfly after unplugging it. The volume control is also biases me down to the lowest levels on my computer and Tidal so I don't lose my eardrums. Seriously, I can't turn the volume up above three or four on each before my ears start to bleed. This has always been a problem with Dragonfly Black. Firmware upgrade to help volume and Tidal recognition may be needed. Keep up good work and thank you Audioquest for taking care of your loyal customers. Link to comment
Bambam Posted October 28, 2017 Share Posted October 28, 2017 I appear to be having an issue with my Dragonfly Red and my MacBook Pro. On initial setup, using with Tidal app, everything was working perfectly. I followed the instructions with the DFR - system preferences and then the audio midi setup - and all was good. I would get the magenta color with Tidal Masters and green with "basic" files on Tidal. All was good. I removed the DFR and then put back in and set up again. Now what happens is the setting in Audio Setup Midi won't stay on the DFR - it diverts to "Built In Output" and it won't let me change back to the DRF. This happens AFTER Tidal starts playing a track. I have all the settings correct in Tidal and have rebooted several times, both the MacBook and Tidal. So what's going on? I don't see the magenta color anymore with Tidal Masters - and it definitely doesn't sound the same as it did before. It simply seems like the DFR is not decoding anything - which seems likely since "Built In Output" is what's highlighted when I'm playing Tidal now. Any ideas? Defective unit now? Link to comment
jft Posted November 2, 2017 Share Posted November 2, 2017 Hello, Using AQ Dragonfly Red with Tidal /Windows 7. Can't get over the blue color, no access to magenta using Masters. Three boxes checked in settings, DAC used as renderer. Last version 1.06 on AQ. Link to comment
Samuel T Cogley Posted November 2, 2017 Share Posted November 2, 2017 On 10/28/2017 at 1:03 PM, Bambam said: I removed the DFR and then put back in and set up again. Now what happens is the setting in Audio Setup Midi won't stay on the DFR - it diverts to "Built In Output" and it won't let me change back to the DRF. This happens AFTER Tidal starts playing a track. I have all the settings correct in Tidal and have rebooted several times, both the MacBook and Tidal. So what's going on? I don't see the magenta color anymore with Tidal Masters - and it definitely doesn't sound the same as it did before. It simply seems like the DFR is not decoding anything - which seems likely since "Built In Output" is what's highlighted when I'm playing Tidal now. Any ideas? Defective unit now? Welcome to the forum! I've used a lot of USB DACs with Macs, and I've seen all kinds of USB weirdness. The first thing I will say is that a reboot is almost never sufficient to clear stubbornly persistent USB problems. I usually power down, and then remove power (in your case, the battery if possible) from the mac for 30 seconds or so before powering back up. Also, if you have a USB hub in the mix, be sure to power it off as well. And also, for the purposes of troubleshooting, don't use a hub. Plug the DF directly into the Macbook. I can't speak to what, if anything, is wrong with the DF. But the symptoms you describe are familiar with other USB DACs I have used over the years on Macs. Link to comment
revand Posted November 2, 2017 Share Posted November 2, 2017 2 hours ago, jft said: Hello, Using AQ Dragonfly Red with Tidal /Windows 7. Can't get over the blue color, no access to magenta using Masters. Three boxes checked in settings, DAC used as renderer. Last version 1.06 on AQ. I could manage it as follows: Just check Dragonfly Red and right of the DAC's name there is a settings wheel. Just check Use exlusive mode nothing else, and it will work. Link to comment
GUTB Posted November 2, 2017 Share Posted November 2, 2017 Just did another MQA vs non-MQA comparison through Roon with a DFR+Jitterbug to a TH900. https://tidal.com/album/78913887 If you can't hear the MQA version is better I don't know what to tell you. Link to comment
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now