A toast to PGGB, a heady brew of math and magic

[Zaphod Beeblebrox]

20 minutes ago, chrille said:

One of them used to comment to visiting friends of hers "Oh those two BIG black coffins in the corners are not housing our dead parents, they are my boyfriend´s  Horn Speakers".

Hilarious 🤣  " and the pictures next to the coffins are not our parents or grandparents either " 😁

[Zaphod Beeblebrox]

@hanshopf Welcome to AS

 

2 hours ago, hanshopf said:

With great interest I read about the PGGB project - especially after use of Mscaler plus DAVE transformed my listening experience - and am a bit confused about the different given tuning options in PGGB. Logically speaking shouldn't there be only one correct setting? 

You are correct, there should be only one right answer/setting but that assumes the rest of the system is also ideal. A majority of those who use PGGB use it with the default settings that maximizes reconstruction accuracy (Natural/Transparent). The other options exists to help someone tune PGGB to their system or preference. Some like a slightly dense presentation while some use tube amps/preamps and would like a little more forward presentation. This is not very different from say Mscalar offering a few filter options though most will go with the most transparent filter.

 

2 hours ago, hanshopf said:

A little "proof of concept" experiment could be interesting. Something like digitizing an analogue tape and then comparing the tape master with the PGGB file. If the experiment is done carefully there should be only one PGGB-setting, which sounds absolutely identical to the tape. And furthermore, if PGGB is doing what it is expected to do, the same file played through Mscaler + DAVE should sound ever so slightly different to the tape.

I dont't think the setup required to accomplish this exists today. You will need a A/D converter that would be able to record at 16FS or higher rate, the same converter should also record at a lower rate (say 2FS). More importantly both the conversions should be of a very high quality. Unless I am misunderstanding you, in which case please elaborate on how that setup would look like including what rates to use

 

2 hours ago, hanshopf said:

Rob Watts recently wrote about PGGB: "If it is a windowed sinc function it is no longer true sinc following Whittaker-Shannon".

I had responded to the series of questions Rob Watts raised here but I will repeat here briefly. A true Sinc filter cannot be implemented for a real world application because it requires a infinitely long filter, it could be approximated to come very close. For this reason, none of the Chord DACs that use WTA are true sinc either as they are also windowed sinc, same is true with PGGB too. So it then becomes a question of how many of true Sinc coefficients does PGGB use compared to say WTA or other implementations, because by the same logic, the more true sinc coefficients the better the reconstruction accuracy. It then comes down to simple math. PGGB guarantees more than 50% of its coefficients are true sinc, so at 2M taps, PGGB is already using 1M true Sinc coefficients which would be easily more than any implementation using just 1M taps in total.

 

Though the experiment you describe was not done for reasons already mentioned, I do welcome similar or other experiments. I would also say that PGGB's default settings  are a result of other experiments that  involved playback of a broad range of tracks remastered using PGGB.

 

[hanshopf]

@Zaphod Beeblebrox

Thank you so much for your insightful reply!

 

18 minutes ago, Zaphod Beeblebrox said:

2 hours ago, hanshopf said:

A little "proof of concept" experiment could be interesting. Something like digitizing an analogue tape and then comparing the tape master with the PGGB file. If the experiment is done carefully there should be only one PGGB-setting, which sounds absolutely identical to the tape. And furthermore, if PGGB is doing what it is expected to do, the same file played through Mscaler + DAVE should sound ever so slightly different to the tape.

I dont't think the setup required to accomplish this exists today. You will need a A/D converter that would be able to record at 16FS or higher rate, the same converter should also record at a lower rate (say 2FS). More importantly both the conversions should be of a very high quality. Unless I am misunderstanding you, in which case please elaborate on how that setup would look like including what rates to use

 

I thought, a conventual digitalization would be sufficient. Even as low as 16/44.1 may do, because theory seems to suggest that CD-standard might even be good enough, if upsampling with PGGB is done afterwards. I would do that as well as digitize the analogue tape in 24/192.

 

A conventional high quality A/D converter should do, as my basic understanding suggests, that A/D-conversion poses much lower "problems" than D/A conversion.

 

If the result than shows that a difference between the analogue tape cannot be discerned with in neither the 16/44.1 nor the 24/192 file after being PGGB processed and the result sounds different to the same file processed through MScaler, then we would know four things:

 

a) conventional A/D converters are sufficient

b) CD standard is sufficient for recording

c) PGGB works in a way we all wish it would

d) its superior to MScaler

 

This at least would be the result I'd hope for. Other outcomes are possible.

 

 

 

[Zaphod Beeblebrox]

35 minutes ago, hanshopf said:

If the result than shows that a difference between the analogue tape cannot be discerned with in neither the 16/44.1 nor the 24/192 file after being PGGB processed

Here how will the analog tape be played back? How does one do this comparison between PGGB upsampled file and analog tape? What sort of playback mechanism need one use?

 

High quality analog tape transfer in both PCM and DSD (2xHD, HDTT  offers many of them) have been remastered via PGGB and have been compared with other upsamplers including those you mention. Similar comparisons have also been done from remastering CDs from other sources too. I would let others chime in on the subjective impressions as I prefer to refrain from offering such impressions.

 

[auricgoldfinger]

In case anyone is looking to pick up some discounted storage:  https://www.amazon.com/dp/B08RK2SR23/?coliid=I31D3R5SE7P2SZ&colid=1O2O3N2HH23ZK&psc=0&ref_=lv_ov_lig_dp_it

 

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[hanshopf]

38 minutes ago, Zaphod Beeblebrox said:

Here how will the analog tape be played back? How does one do this comparison between PGGB upsampled file and analog tape? What sort of playback mechanism need one use?

I would connect the output of the tape machine to the same headphone amp to which I would connect DAVE.

Thus the sound of the PGGB file should be identical to the tape (or at least more similar than through Mscaled file), if PGGB works as theory predicts.

[Zaphod Beeblebrox]

22 minutes ago, hanshopf said:

I would connect the output of the tape machine to the same headphone amp to which I would connect DAVE.

Thus the sound of the PGGB file should be identical to the tape (or at least more similar than through Mscaled file), if PGGB works as theory predicts.

Fair enough, I do not have such a setup but I know a few PGGB users with analog setup too, I would let them respond if they so wish.

[hanshopf]

This is such a curiosity driven community, that I hope someone will take the effort.
 

I would love to do this myself, but neither do I have a tape machine nor would I probably hear well enough to get reliable results.

[mitchco]

On 6/20/2021 at 2:37 PM, romaz said:

PGGB - EQ / Room Correction Edition

 

Here is the listening room I wish I had:

 

 

This is the Magico listening room in Hayward, California.  This room reportedly cost $250,000 to build.  It measures 33' x 22' x 13'.  It is a room within a room.  The outside walls are 5" thick Quiet Rock.  The inside walls are composed of 2 layers of sheet rock.  The floor floats meaning it has no interaction with the rest of the room.  The room was designed to have minimum gain and a noise floor of only 24dB.  According to Alon Wolf, Magico's founder, "It's very easy to measure a speaker above 800Hz, regardless of the room it's in. Below that, it gets tricky. Hence, the environment in which you listen to and test your loudspeakers is crucial...So I've taken the room out of the equation. In this room, you hear the bass from the speaker alone, not from the interaction of the speaker with the room. This helps us voice loudspeakers more accurately." 

 

I have enjoyed listening to music in this room on a few occasions and regardless of the speakers and the electronics that were in the room that day, each time, I came away feeling deeply envious.  If I could use one word to describe it, it would be "balanced."  Not too lively and not too dead and everything sounds natural.  Ambience, imaging, clarity, natural decay, this room portrayed it all.  It has been said that your room is your most important component.  After listening to music in this room, I've become a believer.

 

Here are photos of my actual listening room:

 

 

 

 

Yes, I know, lots of problems.  As you can see, it's not a dedicated listening room.  Aside from my Wilson Alexia Series 2 speakers, I'm not allowed to have any audio electronics showing.  I've tried various room treatments from bass traps to various diffusers and absorbers but they kill the look of the room and so with a few exceptions (Synergistic Black Box and a few HFTs and other resonators), I live with the speaker placement restrictions that I have and the natural resonances of this room.  Fortunately, despite my limitations, at my listening position, my room measures pretty smoothly with no horrendous peaks and valleys and listening to music in this room has been very enjoyable.  

 

But each time I experience a really good sounding room (like the Magico or the Taiko Audio listening room), I can't help but want to make improvements and so on more than a few occasions, I've dabbled in room correction or DSP.  I've tried products from Denon (Audyssey), Lyngdorf, and DEQX.  I've brought in speakers that incorporated DSP like the Kii Three.  These solutions did not work for me.  I had my room measured and I enlisted the services of highly respected people like Uli Brueggemann and Mitch Barnett.  I can't say enough good things about these individuals and the services they provide.  They clearly know their craft and were very pleasant and enjoyable to interact with.  I learned a lot about minimum and linear phase filters from Mitch and after much trial and error, I settled on a group of mixed phase filters that I felt were generally to my liking.  The problem with these filters, ultimately, was transparency.  They did some good things but also did some not so good things and so there was always some tradeoff.  I also found that some filters sounded good with some tracks and horrible with other tracks and so this bothered me.  For example, my preferred mixed phase filter did a nice job smoothing the bass with a certain bass-heavy track from Fink or Daft Punk but with Tchaikovsky's 1812 Overture, as the cannons go off at the end, instead of an explosion, all you hear is a compression.  A dud.  Ugh.  Simply horrible.  With time, I found myself not using any of my room correction filters because implementing them for some tracks and removing them for others was more trouble than it was worth.  I figured that room correction technology, while good for movies and certain types of amplified music was not so great for the natural expression of unamplified acoustical instruments and this is what I listen to the most.  What was especially missing were natural extension, depth, and decay.  

 

For some time, I've been aware of @Zaphod Beeblebrox's background and interest in EQ and room correction.  On several occasions, he's encouraged me to give it another try because he felt he could more properly implement it within PGGB.  Based on my disappointment with previous experiences, I didn't prioritize it very highly but eventually I got around to giving it a try.  Because of how much more transparent sounding PGGB made my library sound, I was cautiously hopeful this transparency would extend to room correction and so I provided ZB with my room measurements.

 

With the first two attempts, I was immediately impressed by the transparency in the bass.  The cannons on 1812 Overture exploded with full extension.  I sensed zero compression in the lower octaves.  I also sensed no truncation of depth which seemed to be the other failing of room correction in the past.  On these 2 counts, this was a big win but I found the midrange and treble to sound too smooth and homogenized.  It became clear that I enjoyed the natural resonances of my room in the higher octaves and he wasn't surprised because he felt the mids and highs were well behaved in my room and so on the third try, he limited room correction to below 250Hz.  Here are the before and after measurements:

 

 

The bright red and blue tracings at the top are the "before" measurements of my left and right channels, respectively, and you can see a fairly prominent dip in the bass below 50Hz in the left channel with respect to the right channel.  If you look at the photos of my room, you can clearly understand why.  There is also a moderate peak at 60Hz with the left channel.   With the "after" measurements, you can see how he boosted the left channel below 50Hz and cut the peak at 60Hz to match the right channel.  He used purely linear phase correction.  He left >250Hz alone.  To allow for easy A/B, he also boosted the overall gain to level match what I was getting with no filter applied.  

 

With this 3rd EQ filter, the results that I got were nothing short of AMAZING.  Bass was extended, full, powerful, clear, defined, controlled, and TRANSPARENT!  I once brought in a pair of REL 212SE subwoofers into this room but I could never quite get them to blend seamlessly enough and at no time did adding those subwoofers ever sound this good with these Wilsons.  Because my D'Agostino Momentum HD preamp and Block Audio SE class A monoblocks are capable of generating tremendous amounts of bass by themselves, bass quantity has never really the issue but never have I experienced this level of bass quality with no apparent compromises in my room before.  What is just as satisfying is that while room correction extends only to about 250Hz, it's apparent that my smeared bass was masking midrange detail because my midrange clarity has also very noticeably improved.  Vocals have taken on a new level of clarity and audibility.

 

This is a remarkable level of transparency that I had not experienced before with room correction.  Room correction with PGGB takes place after upsampling but before noise shaping.  Whether the order matters or not in the re-mastering process is not clear and so I will leave it to ZB to discuss the technical aspects of what he has done to the extent that he feels comfortable but clearly, he has accomplished something very right.  There is also the option of time domain correction but with further analysis, he did not feel my room would significantly benefit.  I am now in the process of re-mastering my entire library once again, this time with this room correction filter in place because unlike in the past, regardless of the track I have applied it to, this room correction thus far has improved everything I've tried it on.  If I were to gauge the level of impact, in my listening room, I would say it is at least equivalent to every other quality PGGB offers.  

 

 

Hi Roy, thanks for mentioning my name and service. It's too bad we never got to try a partial correction on your system. I am pretty sure this is the reason why you feel the the filters are not transparent. I have examined the filters extensively produced by Acourate, Audiolense and recently Focus Fidelity, and there are no technical issues with the filters produced.

 

As a comment, I do notice low frequency preringing in the Audiolense frequency response chart you have posted. Can you post the step response chart so we can have a look. Or feel free to send me the measurement and I would be happy to have a look.

 

Kind regards,

Mitch

[romaz]

On 6/23/2021 at 4:37 AM, mitchco said:

 

Hi Roy, thanks for mentioning my name and service. It's too bad we never got to try a partial correction on your system. I am pretty sure this is the reason why you feel the the filters are not transparent. I have examined the filters extensively produced by Acourate, Audiolense and recently Focus Fidelity, and there are no technical issues with the filters produced.

 

Hi Mitch, it's nice to hear from you.  If you recall, you did provide me half a dozen or so partial correction filters (tuned for both timing and tone).  Here is one of them:

 

 

On 6/23/2021 at 4:37 AM, mitchco said:

As a comment, I do notice low frequency preringing in the Audiolense frequency response chart you have posted. Can you post the step response chart so we can have a look. Or feel free to send me the measurement and I would be happy to have a look.

 

I can't comment on the low frequency preringing you're talking about since that's beyond my technical understanding but we used the same room measurements that I had sent to you last year and based my current preferred filter off of one of the partial correction filters you made for me.  I think ZB basically made a linearized version of it with no resampling and integrated it within PGGB with volume leveling which is nice since I don't have to fiddle with gain when switching back and forth to other sources like Qobuz streaming.   For the sake of my understanding (and the understanding of others), if there's something that can be improved further with this preringing that you're talking about, I would appreciate knowing more.  I was certainly more than pleased with our interaction and felt the time we spent together was very worthwhile and educational.  Hopefully, I have not cast doubt on your abilities as I feel they are first rate.  The problems perhaps lie elsewhere.

 

First of all, the UMIK-1 USB mic I used is apparently limited to 48kHz and since >95% of what I listen to is 44kHz based, I was told my mixed phase filters for the music I listen to the most are compromised by the fact that they have to be sample rate converted with a low pass / brick wall filter.  It seems I need to do a better job making room measurements with better equipment and so that's on me.

 

Second, PGGB has literally been a game changer in my system.  These remastered files are the most transparent versions of my music that I have ever heard and it would appear there is something to be gained by applying room correction EQ during the re-mastering process but specifically after upsampling and before noise shaping.  I can't comment on the technical reasons why but the superior transparency of this EQ filter is dramatic and I wish you could hear what I'm hearing.  Here is a post from Rob Watts.  Maybe this explains it:

https://www.head-fi.org/threads/watts-up.800264/page-19#post-13618340

 

Perhaps a collaboration between you and ZB will raise the bar higher.  I would very much be in favor of that.  I know he speaks very highly of you.

[Zaphod Beeblebrox]

27 minutes ago, romaz said:

I think ZB basically made a linearized version of it with no resampling and integrated it within PGGB with volume leveling

 

@romaz Minor correction, as you said, I used the same measurements, but I did alter the EQ to match your preference, but the partial correction was inspired by Mitch's partial correction because you indicated that to be the one you had preferred out of the lot you had tried.  

 

Increased transparency sometimes shifts the tonal balance toward the thinner side and often times we long for bit more bass. 

Because you had indicated you already liked the natural response of your room, and were missing some 'bloom' I changed the partial correction to where the target response was closer to how your right channel looked, slightly elevated instead of flat below 200Hz.

 

Note: PGGB-EQ uses the frequency response information only to create a new EQ filter, it does not use time correction nor does it resample the filters. 

 

Partial correction that Mitch provided, which I incorporated in PGGB-EQ and you liked but felt could use more bass.

 

Final Partial correction that alters target to your preference in bass response, which I incorporated in PGGB-EQ and you liked best.

 

 

[mitchco]

Hi @romaz and @Zaphod Beeblebrox My wife and I were mountain biking in Whistler last week when I wrote that and we just got back today as the massive heat is upon us.

 

 

Roy, I recalled incorrectly. We tried a number of corrections and I forgot about the partial correction. I am not sure if this changed or not, but a good partial correction frequency would be between 300 and 400 Hz. I would also revisit the True Time Domain (TTD) correction as running it without and then with, you will see in the simulations that you can lower the low frequency group delay in your room with TTD on. This will be perceived as a clearer, more defined bass response. 

 

I totally get the need for more bass :-) But it looks like in the new charts, it is starting to roll-off at 40 Hz, down -5 dB at 30 Hz and -10 dB at 20 Hz. In my chart, it is -3 dB at 20 Hz. Keep the bass bump that you like, but you may want to extend the response to get the low bass that the Wilsons are capable of.

 

@Zaphod Beeblebrox re: Note: PGGB-EQ uses the frequency response information only to create a new EQ filter, it does not use time correction nor does it resample the filters.

 

Does that mean PGGB-EQ is not compatible with excess phase correction? Or does it mean it does not change the excess phase correction that is built into the FIR filters and remains intact?

 

Kind regards,

Mitch

[Zaphod Beeblebrox]

9 hours ago, mitchco said:

Does that mean PGGB-EQ is not compatible with excess phase correction? Or does it mean it does not change the excess phase correction that is built into the FIR filters and remains intact?

@mitchcoit is neither, and let me explain why. 

 

PGGB-EQ by default will use the frequency response of the correction filter and create its own linear-phase filter at the desired output rate(s), in doing so it does discard excess phase-correction. This is my recommended and preferred configuration.  

 

However, if someone  wishes to apply TTD correction, PGGB can accommodate that too and the excess phase correction will remain intact. When someone wishes to try it, I let them try both with TTD correction and PGGB-EQs default linear phase options and decide which they want to keep.

 

I have used  and continue to use Accurate and Audiolense XO (I did use your excellent guides and posts to familiarize myself with these), but there is a reason I do not recommend mixed-phase correction. While like you said, I have heard improvement in bass (clarity and control), when there is a significant improvement to transparency brought about by upsampling, I found the excess phase correction to impede rather than aid in transparency while linear-phase filters as designed and implemented within PGGB-EQ just got out of the way with no perceivable change in depth or transparency. 

 

I think the reason for my observation are two fold

1. Typical measurements are done at 48kHz using a USB mic and to generate mixed phase filters at different rates, these are resampled at different rates to create filters at 44.1kHz - 384kHz. the resampling process introduces timing uncertainty in the resampled filters and these when convolved with music signal results in reduced transparency of the reconstructed signal when compared to just using linear phase filters.

2. Even when the measurements are done at different rates (I use a Earthworks M30BX with Lynx Hilo), even when the TTD correction is done at native rates without resampling, linear phase filters resulted better transparency/depth then using mixed phase filters. This made me conclude that excess phase correction negatively impacted timing accuracy of reconstructed signals.

 

I can only base this on my observations and from feedback  I received from those who have tried. If someone wishes to try TTD correction, I will accommodate that and let them decide.

 

In the case of @romaz, he indicated that he already had tried mixed phase correction  but was not happy with the results, and so I had asked him to try PGGB-EQ with linear phase filters which is what he reported. 

 

 

 

 

 

[ASRMichael]

Where do I start…..first off reviewing is not my forte. So I’ll be brief! 
 

@The Computer Audiophile what you have created on your forum is nothing short of extraordinary. I’m amazed by the amount of Brainiac’s we have on this forum. (other forum members words) well done. Mitch & ZB being at the forefront! 
 

First off, big thanks to Mitch for his patience, with me & my room. This is the 2nd time I’ve asked Mitch to create convolution filters for me. 1st time around I liked what the convolution filters were doing. The only issue was I had to use HQP. I prefer the sound from Euphony Stylus so this meant there were trade-offs. I was switching back & forth and finally settled on not using convolution at all. This had nothing to do with the files Mitch created for me. 
 

4 months ago I bought PS Audiophile Guide. There was a section on how to properly setup your speakers. After 12 hours & following the procedure I finally got my speakers into a position where I thought wow! Not only do I have amazing imaging but I have depth, width the lot. The imaging is rock solid, doesn’t let other  instruments enter the imaging. Icing on the cake stuff! It was happy days!!! 
 

Then came along PGGB.. I’m not going to go into the benefits of PGGB but it took my whole system to another level! Another wow moment!!  Then I posted “wouldn’t it be great if PGGB could do convolution” I got a reply from ZB saying it does. So I emailed him asking what I needed to do. He explained I would be a early beta tester. 
 

I then contacted Mitch again & sent him my new measurements from my new speaker & seating position. To my surprise my new speaker & seating position measurements were nowhere as good as my previous position. I explained to Mitch I don’t want to move my speakers. I explained what I had achieved from above.   What transpired was I was now sitting in a null. With Mitch’s extreme patience he managed to create really good DSP. Photo attached. 
 

I then sent Mitch’s files onto ZB, he needed them to create a single set of files (352 & 384) for PGGB. ZB actually sent back two sets of files. 
 

Both files returned were from Mitch’s great convolution files he sent me. (I wasn’t aware if this at this point)
 

1 was completely untouched and 2nd was ZB using his EQ dust (ZB’s words) or linear Phase EQ. 
 

So I upsampled a few songs using PGGB & Mitch’s untouched filters. 
 

Played few songs and thought “Yes” all I loved about the 1st time Mitch created filters was there and all the benefits of using Euphony Stylus were there too. Happy days! One of them moments where you say touch nothing! 
 

For complete sanity I tried using HQP again with new files. Unfortunately I experienced the same as last time. It didn’t work for me. I thought must be my DAC! Sounded flat/dull! 
 

I converted more song sat back and listened carefully! Thinking why even try ZB EQ dust? Well I got the itch…..and the itch has been well scratched. 
 

 Al Jhonson once said:

"Wait a minute, wait a minute I tell yer, you ain't heard nothin' yet" (ZB will laugh at that)
 

I said what is going on here? I quickly emailed ZB and asked how did you create this?, please send me his frequency response picture. He replied quickly saying he’d done nothing to Mitch’s convolution files other than add his proprietary EQ dust. I have absolutely no idea what he has done other than to say he has taking Mitch’s already incredible EQ files to another level. I’ve not heard anything like this before.

 

So what are the differences between EQ dust & not?

 

What I’m hearing is it has so many more layers of music than the other. Sound comes from left,right speakers, centre image, centre image to left & right. Then you add in the depth of layers & separation is insane. Then you add in totality which seems so real. Nothing I’ve experienced before. 

 

What this tells me is…Mitch’s great files he produces are only one part of the puzzle. 
 

The other part which I consider now to be a very large part is the implementation. Whatever PGGB is doing it’s doing it right. 
 

I appreciate not a fair comparison because PGGB is offline upsampling & EQ, but I compared it to HQP upsampling & EQ. As I expected it was night and day. PGGB EQ very clear winner indeed! 
 

Now time to convert my whole library! By then my Taiko ATX & unregulated LPS should be broken in! Coming up to 3 weeks! 
 

Just last point. Working with ZB has been amazing. Reading through some of ZB explanations/responses to my emails has been an amazing experience. You know the feeling when you realise you are dealing with a brainiac! & to top it all he or she is a massive Starwars fan like myself! I’m 43 years old! Being a Starwars fan myself keeps me young! 
 

I encourage people who tried convolution/EQ before and didn’t like it to give PGGB EQ a go! You have nothing to loose. Complete game changer! I’m 

 

I believe from ZB if enough interest this feature will be added to up & coming releases. PM for details. 
 

Thanks again @mitchco @Zaphod Beeblebrox
 

 

[edwardsean]

2 hours ago, ASRMichael said:

You know the feeling when you realise you are dealing with a brainiac! & to top it all he or she is a massive Starwars fan like myself! I’m 43 years old! Being a Starwars fan myself keeps me young! 

 

I went to Axpona every year until the pandemic temporarily closed it. Yet, the last one was different.

 

I walked into the main hall and was startled by how empty it was. This was before Covid existed. I was able to casually stroll through swathes of emptiness like the blackness of outer space itself. When I sat down at a table to try some headphones I was swarmed by seven sales folks who had traveled out from California. It was weird; they were all staring focused on just me, 7 to 1, as I listened. I met some friends who were manning a booth and so I asked them, "What is going on this year?" They looked back at me and said two words: star wars.

 

There was a Star Wars convention in town (Chicago) and all the nerds were there! And, if you take away the nerds from audio who's left? Listen, I too am a nerd, and a huge Star Wars fan–huge–huge but not "massive." I ask this of you all, if forced to choose, must we not choose audio? I know, I know, Star Wars changed my life too! But, I have my priorities straight. 

 

Phones before Clones!

[LowOrbit]

To briefly add my experience with PGGB< ZB and EQ following from ASRMichael above:

 

I bought a PGGB  license last week, stuck some additional RAM into the PC I built last year for running HQPlayer (and VR). I garbleblasted some files and, having added an SRC-DX (thanks to Fourlegs for making that an easy thing to do here in the UK), I finally heard what others were reporting.

 

So I whipped up an EQ file (I have been using HQP convolution to tweak my Raal SR1a 'phones for a year or so, homebrewed using rePhase to perform the necessary bass lift and smooth out the treble), pinged it off to ZB and quick as a flash I had a PGGB EQ correction file. 

 

I spent the weekend with some familiar tunes re-worked using the PGGB magic. It's eveything I hoped it would be - all the resolution and good stuff everyone else has reported - but the big win is just how damn easy it is to relax into the music, the sense of ease and realism. All the bits of music fit together a little bit more convincingly.

 

ZB is very responsive, the software works a treat, it yields insights and brings out the good things in music and the logistical challenges of file storage seems a small price to pay overall. 

 

I have not put the MScaler back into place. Chain is diy W10 server, HQP for replay from RAMDisk or SSD. USB out (Matrix Audio Element H USB card with outboard power via SLA/shunt regulator) to SRC-DX, Wave Fidelity Stratos cables into DAVE onto Jot R/Raal SR1a. Mains cables are screened but not fancy. Mscaler does not match the sense of ease or offer up the realism of space and instrument, but it's plug and play convenience still has a place in a streaming context and it's far from disappointing. Just now the bar has been raised.

 

Zb truly knows where his towel is.

 

 

[happybob]

Flac vs Wav vs AIFF for the INPUT source file for PGGB - does it matter? (as long as it's lossless of course and as HD as available).

There are lots of posts on this thread regarding final PGGB output format and how Wav (or maybe AIFF) is best, and that FLAC doesn't support 16FS (which is what I'll use for my Dave) and those all make sense. However, I'm about to (but haven't yet) purchase/download lots of music that I was previously just streaming via Qobuz - and I'm wondering if there's any reason NOT to use Flac for these downloads (to save space and perhaps optimize tags) given that I'll only be listening to the final PGGB-upsampled/processed 16FS output file/track (which will always be Wav format for me). I've done some testing on this and can't hear a difference - but maybe others have done more extensive testing and that there's possibly a clear consensus on PGGB being indifferent to Flac vs Wav vs AIFF for its input file.

Thanks for any thoughts on this or pointers to posts where this may already have been dealt with.

[edwardsean]

PGGB: A Totally Subjective, Pan-Galactic Gargle-Blasted Review

I found out about PGGB yesterday. I just purchased a license today. ZB lets you trial for 30 days, I didn’t want 30 minutes. I wanted to buy it from the first few seconds I heard it 24 hours ago. I mustered restraint by habit of a long hard won audio discipline. We’ve all learned that things are not always as perfect as they first appear.  But, then again, some things are so good you just know from the get go. PGGB is that good.

 

Nevertheless, I waited because psychology challenges the best of our critical listening. This was going to be the only time I was completely free from any influence of, “You better like it, you bought it.” So, I waited and formed my impressions before I was committed, but all the time thinking, c’mon there’s no way I’m not going to buy this. It is that good.

 

Background: XiSRC to AuI to Roon/HQP to HQPPro and the Joys of Going Off-Line

My system is comprised of the usual suspects: Server+Euphony+customized Farad PS > Fibbr optical (LPS1.2) > Innuos Phoenix > Sablon > DAVE+SJ DC3+SynRes Atmosphere Level 3, Mundorf silver/gold cabling, Orange fuses all around.

 

I started using off-line upscaling about three years ago. There are distinct advantages to preprocessing. Firstly, you avoid all the noise of real time upsampling and all the mitigating strategies that go with it, including having to use a separate server and renderer. I think it's an elegant solution that can potentially cut down multiple noisy components and cables and so improve SQ. Secondly, you aren’t limited by compute power in the way you are by real-time processing and its latency. Thirdly, I don’t know if you’ve tried it, but strapping an Mscaler and a car battery to a Hugo2 is not a good portable solution (I haven’t tried it. I’m just saying). With off-line upscaling you could dissolve the process and bake it weightlessly into your tracks. Once the 2Go came around, this strategy made the Hugo2 a formidable portable performer. Lastly, the files could be duplicated for any and all your devices including little DAPs without any real I/O.

 

Unfortunately, at the time, the only notable SW upscaling was in real time from Roon or HQP. There was virtually no preprocessing options, and certainly nothing that could rival an Mscaler. There was a small company called Xivero that had a decent quality upsampler: XiSRC. It’s since shut down, but back then it provided me with my first results that were more improvement than more error. Next came Audio Inventory’s (AuI) more sophisticated algorithms. Much more expensive, but only slightly better. Of course I paid it, but I started hearing that Jussi of HQP was going to release a pre-processing file converter version. I got my hands on the first demos and this was it. He was bringing his prodigious talents to an offline version. Given where I was coming from the results were stunning. So was the price as it was pitched for pro audio not the consumer market.

 

I’ve corresponded with Jussi about offering a consumer version, but he did not feel there was a real advantage to going off-line for HQP users. However, I’ve spent serious sessions comparing HQP live vs HQPP and, to my ears, preprocessing files with HQPP is superior. The algorithms are the same, but using it off-line in the system made a difference. It would be wonderful if PGGB changed Jussi’s mind and he developed his own consumer version without any real-time constraints.

 

So, for the last 24 hours, minus some sleep, I’ve been comparing HQPPro files to PGGB. I do think this is a fairer fight than HQP desktop to PGGB.

 

HQPPro vs. PGGBlaster

It’s been a while since I’ve done such extensive, intensive critical listening of HQPP files. I remembered anew why I was so impressed with HQPP. Especially, rendered off-line, the lower noise floor really allows Jussi’s fine-grained work to shine through. Compare to redbook, it wonderfully increases the resolution of micro-details in both the sonic components and the spatial cues in between. HQPP really brings a healthy slice of Mscaler-like improvements into files you can take anywhere with you.

 

I have to say though, going from HQPP to PGGB is a bigger jump than from redbook to HQPP. The experience went like this. At first I noticed how much more planted vocalists were in front of me. They held center sound-stage in a more definite and confident way. In fact all the performers and instruments gained substance, definiteness. This struck me so immediately that I first thought that the soundstage had closed in. It wasn’t the space that had been reduced but rather that hazy, diffuse quality that can feel like space. PGGB populated the environment with notes of greater solidity. This might feel more cramped except that, as there was more of the players, there was also more of the stage. Once I was immersed into the venue it was a joyous thing to open my eye/ears and see/hear that every dimension had expanded around me. It is one of the great pleasures of upgrading audio to hear both more close-up detail—and—more space simultaneously.

 

It is these kind of “impossible” improvements that prove, at least to me, that I’ve made a genuine upgrade. The picture PGGB creates is both more dense—and—more spacious, more clear—and—more smooth. You can use all sorts of algorithmic tricks to make audio sound more full/smooth, but sonic shortcuts will also reveal muddiness under scrutiny. You can also artificially boost a sense of space but are left with an image stretched thin and hollow. Moreover, distortion/noise can alternatively excite a signal, masquerading as clarity, or it can mask the signal making it sound thicker. In due time, both effects reveal themselves as unnatural through a telltale fatigue.

 

The only way you can create a sound that is truly clearer and denser and smoother and more precise and more spacious is by actually improving SQ. That is what PGGB has done, and why, for my part, I believe it is a real advancement. The most efficient way to describe the results of PGGB is that its improvements are organic and holistic. It improve sound all the way around: staging, texture, timbre, timing, etc. etc. Build a better waveform and the sonic world will beat a path to your door in perfect rhythm.

 

 

The Answer to the Ultimate Question of Life, the Universe, and Everything (Or, at least why I like PGGB for, you know, listening to music)

I kept thinking to myself, “This is why people like vinyl,” though I will always prefer the benefits of digital. It brings me back to why I listen to music in the first place. There is an entire academic discipline dedicated to the philosophy of music. What exactly is music and why is it so important to people anyway? The most illuminating answer I’ve found comes from the work of Peter Kivy. He poses something called “contour theory.” Without getting into the weeds, it states that music is able to replicate the “shapes” of life in a tangible manner. A rapturous arpeggio of rapidly ascending notes doesn’t just sound like elevation and release. You feel its contour palpably through sound. The visual arts are just as powerful, but they have no ability to press upon us with volume. I don't mean "volume" as measured by dB, but in the way real things have mass and dimension. Music can reproduce the geometry of our experiences of life in ways that actually move the air around us and is, in turn, able to move us, literally and emotionally.

 

In order to do this you can’t just produce a clear window into music. You have to enter in and sculpt the sound in such a way that gives substance to its shapes. Some designs seek to accomplish this by, what feels like, a sonic thickener spread across the spectrum. PGGB’s success is in how effectively it is able to surgically carve out sonic components. The parts gain weight as the space between them is removed, all the while preserving minor details. The vibrations of voices, reeds, and rosin resonate more viscerally into a space that better conveys their reflections. This is what makes music real, that is, life-like, in the way that Kivy muses that music is like life itself. By addressing the problems of audio, at the waveform level, PGGB better reproduces the contours of music which reproduces the contours of life.

 

To give all credit to where it’s due, ZB is quick to point out how others pioneered the field, but all credit to where it’s due, PGGB is cutting one gorgeous path forward. As someone who gets to journey in these audio trails, I’m grateful to everybody. Since 24 hours ago though, I really want to thank ZB, and Roy, Rajiv, and Ray (or was it 42 hours ago?). Does your name have to start with an ‘R’ to achieve audio greatness? Another of life’s big questions. 

 

Don’t Panic-TL:DR:

PGGB makes everything sound more real, and that is real good.

 

 

 

 

[Nsxturbo]

7 hours ago, edwardsean said:

Music can reproduce the geometry of our experiences of life in ways that actually move the air around us and is, in turn, able to move us, literally and emotionally.

This is the best distillation of why I’ve been an audiophile for over 30 years and why listening music has played such a supportive role throughout the emotional ups and downs of my life! It is truly essential to my wellbeing. Thank you for such a thoughtful post. You have made my day!

 

I plan on allocating my next system upgrade funds to PGGB.

[Zaphod Beeblebrox]

9 hours ago, happybob said:

Flac vs Wav vs AIFF for the INPUT source file for PGGB - does it matter? (as long as it's lossless of course and as HD as available).

There are lots of posts on this thread regarding final PGGB output format and how Wav (or maybe AIFF) is best, and that FLAC doesn't support 16FS (which is what I'll use for my Dave) and those all make sense. However, I'm about to (but haven't yet) purchase/download lots of music that I was previously just streaming via Qobuz - and I'm wondering if there's any reason NOT to use Flac for these downloads (to save space and perhaps optimize tags) given that I'll only be listening to the final PGGB-upsampled/processed 16FS output file/track (which will always be Wav format for me). I've done some testing on this and can't hear a difference - but maybe others have done more extensive testing and that there's possibly a clear consensus on PGGB being indifferent to Flac vs Wav vs AIFF for its input file.

Thanks for any thoughts on this or pointers to posts where this may already have been dealt with.

The format does not matter to PGGB as long as it is lossless and is one of the supported formats. They are just containers and the data inside is same and sometimes it is compressed. Then it comes down to tagging and FLAC works best with PGGB for tagging, so I will recommend download as FLAC. FLAC  also allows embedding images which PGGB will transfer too.

[ingemar]

Hi all.

At the moment i'm using a antipodes dx3 together with a intel nuc 9 pro kit for the processing of hqplayer.My question is,can i use this software with this setup when the music files is stored on the dx??

Kindly/Ingemar

[Zaphod Beeblebrox]

16 minutes ago, ingemar said:

Hi all.

At the moment i'm using a antipodes dx3 together with a intel nuc 9 pro kit for the processing of hqplayer.My question is,can i use this software with this setup when the music files is stored on the dx??

Kindly/Ingemar

Perhaps @kennyb123 or @Fourlegs can help answer this.

[Juice Hifi]

 

 

[ted_b]

@edwardsdean, a couple of questions about your marvelous post.

1) As an HQPlayer experienced user did you gargleblast some DSD over the past 24-42 hrs too?  If so, how does it compare to Jussi's DSD modulated playback (given Dave's more than obvious PCM bent)?

2) What player are you now using, now that no post-processing is being done...still Euphony Stylus?  Do player differences matter less now?

 

I am quite taken by all this feedback, especially Edwardsdean's and many of Romaz's and Rajiv's comments.  HOWEVER, I have not heard the head-over-heels feedback from non-Dave users (or more broadly non-Chord users)?  If this makes Dave unique, then what is the overall cost of a Dave-with-Sean-Jacobs dac solution (as I contemplate upgrading my Spring to the May I've been listening to, on loan).  Note: this by no means infers I'm even contemplating walking away from our beloved DSD.   🙂   I have terrabytes upon terrabytes of wonderful multichannel DSD that I will continue to play through my exaSound.   But the simplicity of offline sampling magic is a very tempting siren. 

 

And one final question/thought: if the Chord Dave is indeed the sweetspot for PGGB, then why?  I realize it is the test bed for PGGB, but what about it is so unique, especially given that some of Rob's magic (WTA filter, etc) is bypassed at 32fs anyway.  Right?  Is it his OCD focus in reducing noise floor modulation that is the secret sauce here?

Thx

Ted

 

[Zaphod Beeblebrox]

2 hours ago, ted_b said:

I am quite taken by all this feedback, especially Edwardsdean's and many of Romaz's and Rajiv's comments.  HOWEVER, I have not heard the head-over-heels feedback from non-Dave users (or more broadly non-Chord users)?  If this makes Dave unique, then what is the overall cost of a Dave-with-Sean-Jacobs dac solution (as I contemplate upgrading my Spring to the May I've been listening to, on loan). 

You raise a very good point. From the perspective of being able to take advantage of PCM upsampling, I don't think it makes DAVE or chord DACs unique. One possible explanation (my own, not based on any kind of survey or statistics) is many chord DAC owners are already 'sold' on the idea that using very long windowed Sinc filter is beneficial and are also familiar with MScaler that replaces the first stage WTA1 of their DAC's processing with a million taps. So it is easier for them to try PGGB with their DAC and many of them like the results and have reported them. I also see this in the number of trial requests I get, a disproportionately large number of the requests are from Chord DAC owners.

 

Logic and math suggests that R2R DACs, especially those that can operate in NOS mode and can accept rates 16FS or 32FS would  benefit from windowed sinc filters in combination with noise shaping to linearize the the last few least significant bits. And a few such as @hols and @sig8 have reported their experience with T+ and May DAC. But I do not know what percentage of R2R DAC owners are open to the idea of software upsampling and some NOS DAC owners like the NOS sound signature. Another challenge with offline upsampling for R2R DAC owners with DACs that can do 32FS is the  size of upsampled files.

 

With regards to (non chord) delta Sigma DACs, it is harder to predict and only way to find is to try. DACs that accept 16FS or higher rates will be good candidates @SwissBear had reported good results with Gustard Pro x26 in NOS  mode at 16FS mode and  @ASRMichael  at 8FS. 

 

There is also the question of personal preferences, system and priorities, It would be great if both positive and negative experience of most who try is posted here to get a better picture and I hope we will learn more over time. 

 

But there is really no substitute to just trying and finding if PCM upsampling works with their DAC, be it PGGB, HQP, AuI or other upsampling solutions. With respect to PGGB, there is also the additional challenge of requiring a PC, Mac or Linux machine capable of running PGGB. I wonder if that is an additional factor for those with non chord DACs who are not entirely convinced of the advantage of upsampling. I hope the new cloud based PGGB service would help those who would like to audition without having to invest in a capable desktop.

 

With respect to DSD, if you are playing DSD via a PCM DAC already, I see no reason to abandon DSD, DSD make a for 30% of my main library, DSD material will also benefit from high quality PCM conversion.  I too own a good number of multichannel DSD that I hope to play once I figure out how to use more than one DAC via ALSA and keep them in sync.