Izotope SRC

[skatbelt]

According to information from Izotope on the various variables there is a direct relationship between steepness and pre-ringing:

 

"Low-pass filters are characterized by the amount of ringing they introduce into their output. Higher Steepness settings produce increased ringing. A setting of 100% produces a linear phase filter with equal pre and post ringing. A setting of 0% produces a minimum phase filter that offers no preringing but has nonlinear phase distortion. Intermediate settings allow a tradeoff between preringing and postringing and allows you to linearize phase in the pass-band."

 

This is exactly what I am experiencing and it makes tuning more complicated than just finding the system (mean) optimum for the 5 variables. I don't want to go as far as defining different 'presets' depending on material or genre.

[skatbelt]

haven't slept for 24 hours or something. coffee tasting very good.

apologies if rambling ensues but just have to post this:

 

suite 1 (with 2 variances) on ver 2.0.7 has delivered something akin to a system upgrade for me.

 

improvements across the board >> airiness, sound-staging, layering, detail, presence, etc.

 

most importantly, music is no longer “played”, it just flows.

 

(present) settings for an early 2011 mbp 2.2GHz/i7 >> hugo:

 

upsampling: power of 2

steepness: 5

filter max length: 500,000 (somehow cannot reduce, defaults to this)

anti-aliasing: 200

pre-ringing: 0.8 (smoother sound + more transparency)

 

have not heard this level/magnitude of improvement since speaker and DAC upgrades.

 

for 16/44.1, as well as 24/88, 24/96 and 24/192 tracks. not sure about DSD though.

 

thank you so much, Jud, for pointing the way here and informative posts.

 

BIG thanks too to levandier for starting this thread, as well as junker, superdad, alexey lukin, miska, barrows, bdiament for leading the way. + everybody else who helped to pave the way.

 

still grasping at some concepts + tech points raised/discussed. no point pretending i can understand most of it.

 

but, holy guacamole. it works so good. can’t stop listening. and grinning like the (computer audiophile tech) idiot i am.

 

cheers to good music + good coffee.

 

btw, suite 3 seems to be the default settings.

 

Well, out of curiosity I tried your settings. It gives me a deep and well ordered soundstage but the presentation of instruments and voices are flat. My own settings (in my setup) are much more life like, I can hear more details (tape hiss, chair movement etc.) but - more important - instruments and voices feel like volumes in space. They do have a front and a back, are more 3D so to speak. As I mentioned above, steepness and pre-ringing are strong related so it took a while to find my optimum. My settings are:

 

Steepness: 83

Filter max length: 800,000

Cutoff freq.: 1,08

Anti-aliasing: 200.0

Pre-ringing: 0.30

Forced Upsampling: Power of 2

[skatbelt]

Your settings are the Bomb!!!!! Great Sound

 

Looks like it is not so system dependent after all...

[skatbelt]

Interesting Result: Applied these settings and have observed a noticeable difference in A+. In my system, which has some similarity to yours, perhaps improved depth & width of soundstage, excellent detail, improved space between instruments. That said, I have always preferred A+ when playing DSD files as compared to Amarra, yet always preferred Amarra when playing 44.1khz and all HiRez files up to 192khz. Something about Amarra has just sounded right - maybe a warmer, less analytically result than A+.

 

I look forward to listening to Redbook CD & HiRez music this weekend to determine if A+ has closed that gap or exceeded Amarra here. No doubt these settings have made an improvement. Thanks!

 

I was an Amarra fan myself from early 2010 until a month ago or so. I tried everything else in trial but always came back to Amarra for sound quality. Even despite of their bad test and quality assurance management and follow ups on known errors. When I tried version 2.0.6 of Audirvana plus I all-most didn't believe my ears. After trying out different 'Audio System' settings that is. My settings now are: exclusive access mode active, direct mode active, and integer mode 1 active. Combined with the SRC settings as described it gives me superior results over Amarra, especially with 44/16 up to 96/24 files. I use Audirvana stand alone (I sync with the iTunes library now and then and manage my files there). I used Amarra in playlist mode most of the time.

[skatbelt]

Your settings works extremely well on my system Thanks so much its make a really huge difference than before !

 

You're very welcome. Nice to give something back after a period of mostly information absorption!

[skatbelt]

Just want to chime in and say thanks as well. These settings compliment my Audioquest Dragonfly v1.2 + JH16s very nicely. Biggest observed change is the details; hearing the most subtle of things coming through. Bravo!

 

Well, looks like it is not comparing apples and oranges after all. It feels somewhat logical that there will be sort of an optimum. Given the fact that the processing is done so early in the system chain. Variables are off course computer specs/configuration, OS and OS optimisation. And I can imagine that different DAC’s and/or converters act different with upsampled input material.

 

For those interested, I fine-tuned the pre-ringing to 0.31 while keeping all other values the same.

[skatbelt]

Is anyone else using a cut-off frequency of 2.0 x Nyquist?

I feel like it's an audiophile faux pas ... like playing ABBA on Vox Olympian horns at a HiFi Show in Paris. So not cool.

 

But as much I've dabbled with other people's settings, maxing out on the Nyquist always sounds better. Maybe it's the ES9018 chip in my Burson DAC... or maybe I'm just a little odd.

 

At 2.00 (actually starting at 1.60 and above) high frequencies get distorted in my system. Sounds like clipping but only in the highest frequency range. For what I read, 'normal' values for cut-off frequency are between 0.90 and 1.15.

[skatbelt]

Just upgraded to Audirvana 2.0.9 and am loving the big open sound. One caveat for me was the openness this update brought revealed an irritating layer of sibilance, making songs like Metric's "Youth Without Youth" or Laura Mvula's "Green Garden" almost unlistenable with the settings I had previously used.

After much futzing around to find a sweet, but open and detailed high end I settled on izotope src settings of:

Steepness: 9

Filter max: 1,800,000

Cutoff: .84

Anti-aliasing: 200

Pre-ringing: .37

 

What version of Audirvana did you come from?

[skatbelt]

Upgraded from 2.0.6

I tried 2.0.7 and 2.0.8 and skipped both because the sound quality wasn't as good as 2.0.6

 

I skipped 2.07 and 2.08 as well. I was happy with the sound quality of 2.06 but I am even happier with the sound of 2.09. Same src settings however and I don't feel the urge to change anything there.

[skatbelt]

However, also these settings show drawbacks to my ears on certain albums (some lack of "saturation" for instance in minimalistic piano concerts).

I really don't care about the perceived "extended soundstage" and "air" between instruments SRC may provoke. I care much more about a consistent, coherent, traceable sound.

 

Often I read about the preference for warmth or as you call it saturation. My opinion on that matter is that your listening preference (and that of many others) is biased from what is really recorded and engineered. The problem with this is that - while some recordings may sound better for you - there will be a shift for all. I think it is the best to strive for honest en neutral playback. In my system, every recording sounds good. But what is the definition of good? Well, as good as it was recorded and engineered. If something is recorded and/or mixed thin, it sounds thin. If the low end is to full, it sounds that way, if the top is too bright, the same etc. I don't want to enter a dangerous territory but I tend to think the above is also the reason why a lot of people prefer vinyl, tubes and more recently the DSD-format. Not because is sounds better, but because it sounds better to their ears.

 

Part of the proces in my search for the optimum src settings was a comparison of 44/16, 96/24 and 192/24 versions of the track 'Lush Life' of this album (Computer Audiophile - Kent Poon's Audiophile Jazz Prologue III) with leaving the last version non-upsampled. I don't know if this approach is scientific waterproof though. Probably not.

[skatbelt]

steepness: 9

filter length: 1,300,000

cutoff frequ: 1.04

AA: 200

pre-ringing: 0.58

 

Same findings as sdolezalek. In my system to aggressive, upfront and harsh as well. And the soundstage becomes less deeper and not as layered as with my own settings. What recordings/tracks do you use for testing purposes? May be it is interesting to compare on that level so we can rule something out as a variable.

[skatbelt]

So far a few of my favorites are as follows:

 

[ATTACH=CONFIG]16550[/ATTACH]

 

'Own early'? You meant my settings...

[skatbelt]

[skatbelt]

What about Filter Max Length and Anti- Aliasing? Why do a lot of people not included those 2 settings when posting setting that they like? Is it just that they just keep the A+ default?

 

Good question! I believe it is generally assumed it is best to keep Anti-Aliasing at it's maximum value (=best quality) unless your cpu cannot handle it. But I did find altering the default value for Filter Max Length makes a difference. Actually I just went from 800.000 to 672.000 after upgrading my AES/EBU cable. I had an entry-level Wireworld and upgraded to a Transparent one (see signature).

 

On a side note: I was a non-believer on the subject of cables making a real difference other than just cool looks until I heard how much difference (not subtle) a USB cable can make. The win with the AES/EBU cable upgrade was less dramatic but still substantial. It gave me me a bit more of everything but especially a tad more realness. Maybe also because this cable has the by Berkeley Audio Design advised length of 1.5m (I use their Alpha USB converter) whereas my former one was only 0.5m.

 

Back to SRC, I found that optimal values for steepness, cut-off and pre-ringing were the same with the new cable but that I had to lower the Filter Max Length for best weight and tautness of the lower frequencies and hence the best soundstage.

 

I realize, my findings make things even more complicated. There are so much dependencies.

[skatbelt]

Something in me says the above settings can not be optimal for speaker playback regardless of DAC type. But may be you did find these settings work well in your headphone setup.

 

For optimizing a (higher end) system in general, the use of a track with a single instrument that has a relative compact physic and can play or excite lower and higher octaves is very usefull. I personally use Christian McBride - Night Train (track) - Gettin’ To it (album) or Antonio Forcione - Night Passage (track) - Live (album). In these tracks, all energy should come from the same (virtual) projection of the instrument and its player in the soundstage. If you close your eyes you should 'see' the instrument. In not well setup or lower quality/bad systems projections become huge, not well defined and/or bass notes seem to come from an other source than higher notes.

[skatbelt]

Hi Dyson. I don't know what you exactly intend to do but I believe it is generally assumed that it is best to keep Anti-Aliasing at it's maximum value. This equals best quality and is advised unless your cpu cannot handle it.

[skatbelt]

That is exactly the problem: all those settings that claims to be purely "optimisation" ones, have in fact much more effects than expected on the sound quality!

 

I try to achieve a filter that keeps the result as close as possible to the original content. I don't want to listen to a filter, I want to listen to the original intention of a musician. When I test the settings I use a lot of different tracks, comparing with and without upsampling (when not up sampling i keep my DAC in NOS mode) redbook content and comparing up sampled PCM to its DSD version.

 

I rely more on my hears (and brain...) than on "mathematical" formulas :-)

 

That's the way you look at it. Assuming that no filter or up/oversampling gives a more pure result is one theory. My experience is exactly the opposite: the use of SRC with the optimal parameters for my system brought me closer to my references...

[skatbelt]

That's not what I said, or at least what I wanted to say...

 

You're right. My misinterpretation.

Leaving Anti-Aliasing at max and out of your tests is probably a wise thing to do and makes life a bit easier...

[skatbelt]

Triggered by a PM of Dyson I thought I'd share my latest findings with iZotope SRC.

 

I am still quite close to the settings I posted earlier.

 

Steepness: 73 dB

Max filter length: 645.600

Cutoff freq.: 1.00

Anti-aliasing: 200.0

Pre-ringing: 0.33

Power of 2

 

The biggest change for me is going back to a cutoff frequency of 1.00. I found the cutoff setting to be more or less comparable to the focus of a lens in photography. So back to front. A value higher than 1.00 leads to back focus, a lower one to front focus. It can be perceived as airiness (in some genres) but it is artificial and leads to a wrong presentation of soundstage depth.

 

The combination between steepness and pre-ringing to my ears acts more as a focus of the stereo image in the left to right plane. Not set right can lead to a stretched or compressed image, depending on the offset. I optimised my settings by striving for realness and lifelike presentation of stringed instruments (violin, cello, etc. but also piano). An offset leads to softness, less realness but can be perceived as more fluent/liquid, analogue, tube like. Not my cup of tea though. I call it distortion, he he...

 

The relationship between steepness and pre-ringing for me is somewhat constant. .01 up in pre-ringing is 3 or 4 dB down in steepness.

 

Since a few weeks and for headphone purposes I own a Chord Hugo. I was surprised to find out that with the Hugo I prefer exactly the same settings as with my Berkeley Alpha USB/Lyngdorf combo.

[skatbelt]

I went big time in the opposite direction. I used a steepness of 144, and filter length of 192,000. Well, I have to say that my original settings sounded better to me.

There seems to be a somewhat smeared sound especially on the higher frequencies and a little less overall clarity with the revised settings.

 

The biggest correlation is between steepness and pre-ringing. See my earlier posts. Did you experiment with lower values of pre-ringing or kept it at 1.00 in your quest?