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

[MarcelNL]

On 7/23/2021 at 4:37 PM, ASRMichael said:

I’m still interested in what other users think of PGGB EQ? 
 

I tried a few songs yesterday using PGGB files but no EQ. Although still sounds amazing, you lose the extra layers & depth of music. 
 

Please report back your findings also

I just converted a couple of tracks I am very familiar with, using an R2R DAC to play them.

 

Initially I thought the process did some good for SQ, as it seems to add some detail, but then I realized it does something to the layers and depth of the recording, as if the time coherence between various instruments in space is messed with making the total combination sound less organic (which is a quality in sound I favor)

[MarcelNL]

if the recording is the issue you may want to listen to what FeralA can do....For me it does more of the same, mess with phase/space/time bit on some occasions it did pull off a lot of the veils present in some recordings made by obviously deaf producers catering for a non discerning audience,

[MarcelNL]

I'm using the PF I2S output into the Metrum, which is a pretty good option!

I'm not very fond of the sound of most DAC's the Metrum and other R2R NOS DACs seem to fit my taste best.

 

I will try some more, yesterday I have also PGGB-ed the same files with different settings (processing took forever on this skimpy laptop), I will compare later today (likely tonight once the grid is cleaner and the town is quieter).

 

First test run I made files using the settings below

Transparency(%)	Filter(kHz)	Cores	Conversion (bits and rate)	Noise shaping
maximally Transparent (Natural)	21	1	16b-44k-to-24b-176	yes

[MarcelNL]

second round:

Maximally Transparent (Natural)

21

1

16b-44k-to-24b-352k

yes

 

[MarcelNL]

just did a quick A-B-C, original WAV, 24bit 176 version and 24 bit 352 version

 

the verdict if this jury:

 

same issue with both 352 and 176, leading AND trailing edges sounds and particularly the overtones are less transparent (even a fraction subdued) and appear smeared, leading to a more mechanical/artificial tone of instruments and voices.

 

For example the piano accompanying Bernarda Fink singing Schubert Lieder appears to have a sort of tiny rattle in the overtones and the attack sounds as someone softened the felt on the hammers in the pggb version, her voice is just more open and organic on the original, the piano also sounds more pointy and organic on the original and the overtones flow more freely. (I know this recording well, and I've heard her sing live)

 

The result may sound great on other systems as what I describe lies deep within the nuance of recordings and playback, my system is capable of detail you hardly hear in most gear as I'm pursuing phase coherence quite while now.

 

Same effect is present on other test tracks that I know well, some of them are the usual 'audio geek' tracks that nobody listens to but to evaluate gear...

 

If I had to guess, eer I have to as I must admit that I have no real detailed clue of what happens under the hood, I'd say that the time relation between fragments of the wave forms are lost.

 

A bit as if you broke your mothers cherished china vase while she was away, but you went to extremes gluing it together and scraping off excess glue -no visible difference, pfew... Then she comes home 'sees something out of whack in the flowers arranged in the vase' she picks it up to correct it and instantly KNOWS something is wrong ..probably just because the sound of the china changed.  it's THAT sort of idea I'm trying to convey.

 

 

[MarcelNL]

I'll try both, lower bit rate and dense, and I'll throw in a busy work. will report back! Also will do some A-B-C with my best mate next week, he has the most acute hearing of anyone I know. 

[MarcelNL]

Borrowing a Chord Dave is as easy as it may sound...the majority of my audio buddies are heavy into Vinyl, which in fact I am going to venture into next....16" idler TT is on the wish list, mono and stereo arms the works.

 

Why would I2S be the bottleneck? Much of the post hoc processing of data is IMO cosmetic, which can be fine when applied wisely and sparsely and the Metrum does process data in the FPGA. Can it be that what Metrum does has a better synergy with the R2R ladders they use?

 

If SQ improves, I'm game.... so far ? Not really, I like the original and the sound I'm experiencing from it through that PF I2S card does not leave me wanting.

 

I will experiment a bit more with PGGB.

 

[MarcelNL]

56 minutes ago, Zaphod Beeblebrox said:

Can it be set to pure NOS mode where it just passes the data through without processing?

nope what you get is what you see, or something similar....

 

What they di they do good!

 

[MarcelNL]

did another quick A-B, original, PGGB @352.... NO match, the vibrancy is gone in the PGGB version, that eery aura around instruments and voices that is made by overtones interfering with each other is KIA.

 

(added a second 8 Pin EPS cable to the MoBo so had to go back to the previous stage)

[MarcelNL]

I have dabbled with DXD a long time ago, but the system I'm now listening to is completely different so that experience is not valid IMO..

At the time DXD seemed to have its merits.

[MarcelNL]

it's pretty much why the first batch of files was PGGBed ending up as 176 OR I am mistaken and got the interpretation of the file details wrong. I am quite familiar with the 192 Khz limit.