• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Minimum Phase vs Linear Phase

mansr

Major Contributor
Joined
Oct 5, 2018
Messages
4,685
Likes
10,700
Location
Hampshire
I like to disagree. The amount of data moved out is the same for both formats (PCM), just the amount to move in is different - with just half of it for FLAC compared to WAV. I don't think that a data rate reduction of 50% compensates the heavy processing of FLAC against almost no processing in case of WAV which contains the PCM data more or less ready for transfer to the DAC. It may well be possible that the CPU sleeps most of the time when handling WAV files.
FLAC is ridiculously cheap to decode. Depending on the CPU, memory system, storage medium, and software (OS and application) architecture, FLAC could plausibly be cheaper to play back than WAV. The system load from either is so low that accurate comparisons are difficult.
 
OP
Ron Texas

Ron Texas

Master Contributor
Joined
Jun 10, 2018
Messages
6,075
Likes
8,908
FLAC is ridiculously cheap to decode. Depending on the CPU, memory system, storage medium, and software (OS and application) architecture, FLAC could plausibly be cheaper to play back than WAV. The system load from either is so low that accurate comparisons are difficult.

I can play back Redbook flac on foobar on a slow Pentium NUC with foobar showing zero CPU use in Windows Task Manager. That's with WASPI push and no DSP's. It doesn't get any cheaper than zero.
 

LTig

Master Contributor
Forum Donor
Joined
Feb 27, 2019
Messages
5,760
Likes
9,442
Location
Europe
FLAC is ridiculously cheap to decode. Depending on the CPU, memory system, storage medium, and software (OS and application) architecture, FLAC could plausibly be cheaper to play back than WAV. The system load from either is so low that accurate comparisons are difficult.
Well, then I have no scientific explanation for @maty's listening results.
 
OP
Ron Texas

Ron Texas

Master Contributor
Joined
Jun 10, 2018
Messages
6,075
Likes
8,908
I am going to revisit the D30 VS DX3 Pro VS Grace 9XX results to see if it's just some problem with the D30 or a difference in the filter settings. I'm not surprised at the response to this thread, given the interests of the members here. It will be next week before I get to it, due to travel and an unrelated shit storm.

I doubt Topping is trying to game the results. My test tracks for this are Cecile Mclorin Salvant, The Window.
 

Guermantes

Senior Member
Joined
Feb 19, 2018
Messages
484
Likes
561
Location
Brisbane, Australia
Is there a "problem" or just a preference? Nothing wrong with liking the sound of one bit of gear over another . . .

If I perceive "harshness", I always look at the recording first. No matter how wonderful the music is, sometimes the recording is just not up to par. Then I might question the transducers. Are they causing or exacerbating a problem?

I have a favourite track for auditioning headphones: Mahler's Der Abscheid from a 1966 EMI recording with Christa Ludwig and Otto Klemperer. There's a point at about 3:33 where Ludwig hits a robust note and the microphone, tape or something in the chain is just starting to saturate. Some headphones I've tried exhibit obvious distortion at this point while some cope better but sound harsh. A good headphone lets me hear it as soft saturation present in the recording. I keep a copy of it on my DAP to audition headphones in stores when I have the opportunity. Incidentally, it's a Fiio X3 II which has the same DAC chip as the Topping D30 (CS4398) but allows selection of two filter types: steep and gradual.
 

maty

Major Contributor
Joined
Dec 12, 2017
Messages
4,596
Likes
3,160
Location
Tarragona (Spain)
I don't doubt that some digital filters may be easy to differentiate. My point is that others are not easy..

Minimum vs linear phase filters. Slow vs slow and fast vs fast.
 

maty

Major Contributor
Joined
Dec 12, 2017
Messages
4,596
Likes
3,160
Location
Tarragona (Spain)
Neither does he...

We all know that mistakes have been made in the designs of the CPU or in the programming of things like ASIO, operating systems, window mixers or ...

The logical thing is that the differences were not appreciated but a few do. Always assume that some of us imagine things is insulting, not taking into account the above mentioned as a possible explanation.
 

Julf

Major Contributor
Forum Donor
Joined
Mar 1, 2016
Messages
3,004
Likes
3,998
Location
Amsterdam, The Netherlands
The logical thing is that the differences were not appreciated but a few do. Always assume that some of us imagine things is insulting, not taking into account the above mentioned as a possible explanation.

The burden of proof is on the one making the claims, and remember, "extraordinary claims require extraordinary evidence".
 

Julf

Major Contributor
Forum Donor
Joined
Mar 1, 2016
Messages
3,004
Likes
3,998
Location
Amsterdam, The Netherlands
I like to disagree. The amount of data moved out is the same for both formats (PCM), just the amount to move in is different - with just half of it for FLAC compared to WAV. I don't think that a data rate reduction of 50% compensates the heavy processing of FLAC against almost no processing in case of WAV which contains the PCM data more or less ready for transfer to the DAC. It may well be possible that the CPU sleeps most of the time when handling WAV files.

As has been pointed out by others, the FLAC processing is quite lightweight, and modern CPU architectures are better at processing than doing I/O.

Anyway in my understanding there is no difference in SQ between WAV and any FLAC regarding the PCM data stored within. However if the FLAC algorithm has a bug then the WAV file is the reference and may sound better. This can easily tested by recreating a WAV from FLAC and a bitwise comparison of this with the original WAV.

Doesn't that test validate the FLAC too? The WAV read/write algorithms can have bugs too...
 

BDWoody

Chief Cat Herder
Moderator
Forum Donor
Joined
Jan 9, 2019
Messages
6,948
Likes
22,625
Location
Mid-Atlantic, USA. (Maryland)
We all know that mistakes have been made in the designs of the CPU or in the programming of things like ASIO, operating systems, window mixers or ...

The logical thing is that the differences were not appreciated but a few do. Always assume that some of us imagine things is insulting, not taking into account the above mentioned as a possible explanation.

To me, the logical thing would be to do more than simply insisting on the difference being real (as if that matters), and stomping your foot when people don't buy it...

You just make bold (often bolded) claims, then support them with more... None, ever, with any kind of proof.

It makes sense that a watermelon would fall faster than a grape. Good thing someone tested it...
 

maty

Major Contributor
Joined
Dec 12, 2017
Messages
4,596
Likes
3,160
Location
Tarragona (Spain)
I made a test with my modded KEF Q100 5.25" coaxial speakers. I had the option of modifying the filter after the great measurements Zvu made of his own. I have chosen, for now, to slightly modify the frequency response, taking into account that I am at the apex of the listening triangle and not in front of a speaker.
Original: KEF-Q100-fabricka-zvu.png and with new crossover: KEF-Q100-modifikovana-zvu.png. Original spectral decay: KEF_Q_100_Wasserfall-x2.png

At 30º, 40º and 50º KEF-Q100-fabricka-30-40-50-zvu.png

Test with a great vinyl rip from a 2018 live concert: https://www.discogs.com/Hans-Theessink-70-Birthday-Bash/release/13317092 with DR13. https://www.amazon.de/70-Birthday-Bash-Hans-Theessink/dp/B07MWZXLXG

Some days with the Equalizer Parametric of JRMC v25.0.98 64-bits, and Win 10 1809 64. Works with minimum filters, RBJ type.
https://wiki.jriver.com/index.php/Parametric_Equalizer

Today with a new free VST plugin, lkjb Qrange. With linear filters.
https://www.kvraudio.com/product/qrange-by-lkjb

The final adjust was by ear.

JRMC-DSP-PEQ-KEF-Q100.png


JRMC-DSP-QRange-KEF-Q100.png


With QRange (linear) the sound is more clear but... "the magic" is out. I like more with the PEQ (minimum), the sound is more natural, credible. The difference is easily appreciated by anyone, at least in my second system.

************ ************

Update: https://www.audiosciencereview.com/...-are-we-listening-to-right-now.40/post-225380

Update 2: https://web.archive.org/web/20180129054829/http://medleysmusings.com/kef-q100-drive-unit-testing/

Update 3: http://zaphaudio.com/blog.html and Ctrl + F -> KEF Q100
 
Last edited:

Julf

Major Contributor
Forum Donor
Joined
Mar 1, 2016
Messages
3,004
Likes
3,998
Location
Amsterdam, The Netherlands
With QRange the sound is more clear but... "the magic" is out. I like more with the PEQ., the sound is more natural, credible.

That sounds like a sighted "test".
 

Veri

Master Contributor
Joined
Feb 6, 2018
Messages
9,596
Likes
12,036
I made a test with my modded KEF Q100 5.25" coaxial speakers. I had the option of modifying the filter after the great measurements Zvu made of his own. I have chosen, for now, to slightly modify the frequency response, taking into account that I am at the apex of the listening triangle and not in front of a speaker.
Original: View attachment 32983 and with new crossover: View attachment 32990. Original spectral decay: View attachment 32989

At 30º, 40º and 50º View attachment 32991

Test with a great vinyl rip from a 2018 live concert: https://www.discogs.com/Hans-Theessink-70-Birthday-Bash/release/13317092 with DR13. https://www.amazon.de/70-Birthday-Bash-Hans-Theessink/dp/B07MWZXLXG

Some days with the Equalizer Parametric of JRMC v25.0.98 64-bits, and Win 10 1809 64. Works with minimum filters, RBJ type.
https://wiki.jriver.com/index.php/Parametric_Equalizer

Today with a new free VST plugin, lkjb Qrange. With linear filters.
https://www.kvraudio.com/product/qrange-by-lkjb

The final adjust was by ear.

View attachment 32987

View attachment 32988

With QRange (linear) the sound is more clear but... "the magic" is out. I like more with the PEQ (minimum), the sound is more natural, credible. The difference is easily appreciated by anyone, at least in my second system.

************ ************

Update: https://www.audiosciencereview.com/...-are-we-listening-to-right-now.40/post-225380

Update 2: https://web.archive.org/web/20180129054829/http://medleysmusings.com/kef-q100-drive-unit-testing/

Update 3: http://zaphaudio.com/blog.html and Ctrl + F -> KEF Q100
Ah yes, "easily appreciated by anyone in my system", almost as good as a proper controlled test :rolleyes::rolleyes:
 

MRC01

Major Contributor
Joined
Feb 5, 2019
Messages
3,422
Likes
4,029
Location
Pacific Northwest
...
It makes sense that a watermelon would fall faster than a grape. Good thing someone tested it...
Well a brick does fall faster than a feather, and a baseball falls faster than a beach ball. At least here on Earth where there is air resistance. Somebody who only read Newton's laws and didn't experiment might think otherwise. True understanding comes from the interaction of theory and experiment, each incrementally refining the other.
 

maty

Major Contributor
Joined
Dec 12, 2017
Messages
4,596
Likes
3,160
Location
Tarragona (Spain)
The logical thing to me is the minimal phase filters if the touch-ups are few and not very aggressive, which is what happens with loudspeakers with a fairly flat response and, in my case, in the near field.

On the other hand, if you want to process the entire audio band then the linear filters seem more logical as the phase does not change as it happens with the first ones, which emulate the traditional analog filters.

As far as I know, the acoustic instruments are of a minimal phase and the recordings that I usually hear come from analog master recordings and with studios with analog filters (minimum phase too) from before the 1980s and the fudges that were made then. And from the master to vinyl or direct to vinyl.

There are exceptions like this fantastic live.

In summary, if the recordings that are heard are modern, with synthesized instruments, voices with Autotune, very digitally processed in the studio then the linear phase is ALWAYS being used from the beginning. And if we also use software for digital correction ....

But then, you will almost always be listening to musical PRODUCTS and not music, I say. Maybe spectacular but without EMOTION. :cool:
 
Last edited:

MRC01

Major Contributor
Joined
Feb 5, 2019
Messages
3,422
Likes
4,029
Location
Pacific Northwest
The logical thing to me is the minimal phase filters if the touch-ups are few and not very aggressive, which is what happens with loudspeakers with a fairly flat response and, in my case, in the near field.
...
With gentle EQ, say 6 dB or less with slopes/Q of 2 or less, I find the difference between linear & minimum phase is inaudible. Anyone doing more aggressive EQ should ask himself: WHY? In this case there probably is a bigger problem that needs a root cause solution, not just EQ as a band-aid on top of it.
 
OP
Ron Texas

Ron Texas

Master Contributor
Joined
Jun 10, 2018
Messages
6,075
Likes
8,908
It shouldn't be hard to improve on the simple, i believe first order, crossover in the Q100
 

maty

Major Contributor
Joined
Dec 12, 2017
Messages
4,596
Likes
3,160
Location
Tarragona (Spain)
It shouldn't be hard to improve on the simple, i believe first order, crossover in the Q100

The new crossover was soft designed to correct the response by taking advantage of the largest number of components of the original filter, to spend money.

Any way, the more substantial improvement was made a year ago: more mass + absorbent (with viscoelastic material). Now the Q100 weigh more than the LS50.
 
Last edited:

maty

Major Contributor
Joined
Dec 12, 2017
Messages
4,596
Likes
3,160
Location
Tarragona (Spain)
To finish, if I am not wrong, the drivers are... minimum phase :)
 
Top Bottom