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Old 22nd April 2015, 06:33 PM   #841
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Paul, I think I prefer C128x100 instead of C128x90. It seems at least to my ears that instruments are more full bodied. But is it possible to provide a C128x80 version to check again? Thank you Panagiotis
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Old 22nd April 2015, 09:24 PM   #842
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Quote:
Originally Posted by PanagiotisPapadakos View Post
Paul, I think I prefer C128x100 instead of C128x90. It seems at least to my ears that instruments are more full bodied. But is it possible to provide a C128x80 version to check again? Thank you Panagiotis
It is interesting you should say that

I've attached C128_80v8.

There is only minor variation in the response. Roll-off seems to begin around 15kHz, and there is a spread of less than 0.5dB at 20kHz where the filters are between 2.5dB and 3dB down.
Click the image to open in full size.
What is noticeable with smoothing set to none, and much higher zoom levels is the effect of reducing sidelobe attenuation. 128-80:red, 128-90: green, 128-100: blue, 128-110: purple, 128-120: orange

Click the image to open in full size.

The 80 and to a lesser degree the 90 show obvious ripple, although even with the 80 this looks to be about 0.00037dB peak to peak, so this well beneath the +/-0.001dB threshold for audible colouration mentioned in Gerzon's article on equalisers.

Roll off and stop band show the trade offs between the two - the 80 rolls off earlier but has the worst stop band performance.

Click the image to open in full size.

tbc
Attached Images
File Type: png Cheb128_comp.png (42.8 KB, 884 views)
File Type: png Cheb128_pb_zoom.png (60.9 KB, 879 views)
File Type: png C128_sb.png (56.6 KB, 531 views)
Attached Files
File Type: zip 1021filtNQ_C128_80v8.skr.zip (1.6 KB, 15 views)
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Old 23rd April 2015, 12:49 AM   #843
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To continue...

This shows the roll-off to 0.1dB of the 4 filters 80, 90, 100, 110.

Click the image to open in full size.

I've had to adjust the 0dB point on a couple of them but ran out of adjust resolution so there are minor differences in 0dB.

You can clearly see the effect of reducing the sideline attenuation with the 110 rolling off lowest and the 80 highest. It looks to me that there is about a 1kHz spread between 80 and 110.

To put things into context lets check the NOS response vs C128_100.

Click the image to open in full size.

The NOS filter is down 0.01dB at 1.1kHz 0.1dB at 3.9kHz and 0.7dB at 10kHz.

I believe the "better bass" that the NOS filter displays is largely due to the gentle roll-off through the mid range and upper frequencies. The effect seems to be to tilt the tonal balance to favour the bottom end.

With the C128 filters the changes are largely in the roll-off point and amount of stop-band attenuation, but I believe the roll-off point is the main distinguishing factor. So even the relatively small differences in response between C128_90 and C128_110 is sufficient to make a difference in the amount of "air" and perceived weight of the bass in recordings.
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Old 23rd April 2015, 03:46 AM   #844
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Default Test Tracks

Just for the record I'd thought I'd list my reference tracks. I don't usually mention them specifically because it's about as exciting as listening to them over and over

Morelenbaum2/Sakamoto: Bonita from the cd Casa released on Sony Classical. The track starts with field recording of wave breaking gently on Ipanema Beach, before settling in to cello, piano and vocals.

Bliss: Right Here from Quiet Letters Vocals and piano. And would you believe, a Danish group?

Miles Davis" So What from Kind of Blue Especially the piano/bass intro, the entry of percussion and attack of drum hits, tonality of turmpet during the first couple minutes.

Aes Dana: Leylines from Leylines Weight of synth pads cf to other elements. Definition of baselines and kick drums, "height" of swirling vocal samples. But basically a track I enjoy listening to: https://www.youtube.com/watch?v=D5OFTGeS7nA

David Sylvian: Before the Bullfight, River man from "Gone to Earth". Awesome recording, checking for drum/bass impact amongst other things. This recording is good enough reference material that "River Man" was one of three tracks mentioned in the 2009 HNRR's review of the Wadia 318i, along side Dianne Krall and Leonard Cohen.
Quote:
David Sylvian's brooding 'River Man' from Gone To Earth [Virgin] was delivered with menacing power and tension, Robert Fripp's delicately droning electric guitar treatments sounding more ominous than ever. The sonic picture was gloriously open and spacious, the subterranean bass lines once again sounding powerful and assured.
http://www.hifinews.co.uk/news/artic...ound;8000/9131

LEDR - check positioning accuracy and height of "Over" and "Up".

Less used

Herbie Hancock Raindance from Sextant Definition of handclaps through the intro, recovery of the studio ambience, but generally just a great track to listen too.

Jaia: Alone from Fahrenheit Project 5

ABC Tears are Never Enough from Lexicon of Love. A difficult recording//bad mastering from first CD release. It can sound good if handled with care as with Izotope SRC - so shouldn't sound unlistenable with a good filter.

Last edited by spzzzzkt; 23rd April 2015 at 03:50 AM.
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Old 23rd April 2015, 06:17 AM   #845
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Quote:
Originally Posted by Stixx View Post
Paul,
my response surely was not directed at you...
It's taken the me best part of three days to even notice the post you were responding to.

Last edited by spzzzzkt; 23rd April 2015 at 06:28 AM.
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Old 23rd April 2015, 06:31 AM   #846
Stixx is offline Stixx  Germany
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never mind
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Old 23rd April 2015, 07:40 AM   #847
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Default looking for the perfect beat...

I like the bottom end of the C128-100 and the air of the C128-90, so I figure there has to be a setting in between that is has a nice blend of tops and bottom end.

As a starting point I've done a C128_95 to split the difference, and to my ears, and on my system, it sounds like it's pretty well balanced.

Obviously I can only account for my tastes and system in listening tests so as always YMMV.
Attached Files
File Type: zip 1021filtNQ_C128_95v8.skr.zip (1.6 KB, 45 views)
File Type: txt 1021filtNQ_C128_95v8.txt (22.1 KB, 33 views)
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Old 24th April 2015, 05:03 AM   #848
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Ok I'm going to take another tack on this.

The C128_95/100/110 seem to be around the sweet spot for the this type of approach to the Nyquist filters. They are smooth, and nice to listen to but in comparison with something like the Izotope SRC they lack a bit of sparkle and punch.

So this an outlier test filter and is probably about as brick wall as the Nyquist filters can get.

I've uploaded to versions one with beta = 20, and a second with beta = 12.25 which is roughly the setting SoX uses by default.


And the test track of the day...

https://www.youtube.com/watch?v=4i3Acuoshgc
Attached Files
File Type: zip 1021filtNQ_K960_1225v8.skr.zip (3.7 KB, 25 views)
File Type: zip 1021filtNQ_K960_20v8.skr.zip (3.4 KB, 23 views)

Last edited by spzzzzkt; 24th April 2015 at 05:05 AM.
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Old 24th April 2015, 05:49 AM   #849
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Should have added the above filters are -0.1dB at slightly over 21kHz and are fully attenuated at 23.5kHz for the K960_1225 and 24kHz for the K960_20.

These are far less coloured than the C128 series.

As an added bonus I've done a C960_140 version, which uses the Chebyshev window and 140dB side lobe attenuation, and is fully attenuated by 24kHz.

At the moment I'm slightly favouring the C960_140 out of the steep NQ filters.
Attached Files
File Type: zip 1021filtNQ_C960_140.skr.zip (3.6 KB, 63 views)
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Old 24th April 2015, 05:23 PM   #850
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Quote:
Originally Posted by spzzzzkt View Post
Should have added the above filters are -0.1dB at slightly over 21kHz and are fully attenuated at 23.5kHz for the K960_1225 and 24kHz for the K960_20.

These are far less coloured than the C128 series.

As an added bonus I've done a C960_140 version, which uses the Chebyshev window and 140dB side lobe attenuation, and is fully attenuated by 24kHz.

At the moment I'm slightly favouring the C960_140 out of the steep NQ filters.
Hi Paul. Just tried the C960_140. It feels much more airy and sparkled than the C128_100 that I was using, with all the nice characteristics of it. Only drawback that I noticed is that "shhh"s are now much more pronounced and distorting.
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