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  • aronson
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Vinyl Ripping Workflow Suggestions Appreciated
Hi all,

I've recently begun ripping my collection of OOP or unavailable-in-digital vinyl titles and I'd greatly appreciate some wisdom from others who have tread these roads.

First, I'm not interested in debating formats, equipment, etc.  O:)  I have what I have and I'm not looking to create reference quality archival needle drops. I'm just looking to create high quality digital versions of the titles I'd like to listen to and enjoy. I'd like them to be reasonably click, hiss and hum free but they don't need to be pristine.

I rip at 192/24 to WAV and then plan on converting to FLAC. My turntable is a U-Turn with a Grado Blue (or is it Black?) cartridge. I run the signal through my Adcom GFP-565 into a Tascam D-3000. I then transfer the files to my Mac.

I am licensed to use the following:

1) ClickRepair & DeNoise
2) IZotope RX5
3) Adobe Audition 2015
4) MusicScope

So, where do I start? I've experimented with click removal, hum removal, etc. Is there anyone who can give me a start to finish workflow (with settings suggestions)? I know one setting wont fit all - or will it? I also know to normalize, split and tag after the fact... I'm more interested in the workflow from raw WAV to pre-normalized file.

Does this make sense? I'm all ears!

Thank you!
Adam

  • DVDdoug
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #1
I don't believe there's much interaction between the various types of noise reduction so as far as I know the order of operation isn't that critical.   You've got some redundant tools, so you'll have to decide which ones work best for you.    (I don't own any of the same tools.)

I usually start with the normal (broadband) noise reduction followed by click reduction.   Just don't do anything that changes the background noise level (normalization of individual tracks or fade-ins/fade-outs, etc.) before trying to remove it, so you can apply the same "noise fingerprint" to the entire recording.   I haven't had the need for a separate hum reduction step.    I sometimes apply a high-pass warp & "rumble" filter. 

In the past, I've used Wave Repair for click & pop reduction.    It does an audibly perfect job on most  clicks & pops and it only "touches" the audio where you identify a defect, but it's very  time consuming (and it won't work with your 196kHz files).   I'm currently working on digitization of a record that was in very bad shape and I'm using Wave Repair after automatically removing most of the defects with Wave Corrector (and I'm not getting "perfect" results).  


P.S.
The "frequency response" of older records seems to vary a lot and I sometimes add some high frequency boost.   (I assume current vinyl releases are better but I've never owned or listened to a record that was made after the introduction of CDs.)
  • Last Edit: 08 October, 2016, 12:52:07 PM by DVDdoug

  • Apesbrain
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #2
First, I'm not interested in debating formats, equipment, etc.
I'm not looking to create reference quality archival needle drops.
I rip at 192/24 to WAV and then plan on converting to FLAC.
I read what you said but I feel the need to point out the inconsistency of these statements.  There is nothing on vinyl that can't be captured at 16/44.  The resulting files will be a fraction the size of what you will otherwise have to work with.  Big files like those you plan to create will take up a lot of storage space as well as require a long time to process through noise reduction.  I'd get frustrated just having to load them into an editor!

  • greynol
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #3
16 bits is more than enough for final delivery.

Frequency response of vinyl can exceed 22.05kHz, however; not that the reproduction of these higher frequencies will necessarily be faithful to what was on the master in any reliable fashion.  Audibility of these frequencies is reserved for children and only when not masked by the rest of the content.

I have yet to read a non-dubious reason for keeping content beyond ~22-24kHz (including arguments centered around needing this "vital information" for post-processing).  I do understand the desire to use more than 16-bits for recording so that the initial level needn't be so touchy, but I reject the commonly spewed FUD about quantization error caused by successive edits.
  • Last Edit: 08 October, 2016, 02:25:24 PM by greynol
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

  • AndyH-ha
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #4
First, high pass filter to remove low frequency turntable noise like rumble. Common filters roll off below 20 Hz. Few LPs of the ~ 800 I recorded and cleaned up had any content below 32 Hz. Often 40 Hz is a better choice.

Declick next. Noise reduction first will make it significantly more difficult to find (especially for programs to automatically find) smaller clicks and often harder to remove more obvious ones cleanly. I frequently do four or five passes of automated declicking, each with different settings, then do manual declicking on what I can hear. I use three basic settings for manual fixes. Since the settings depend very much on the application program, I can't suggest settings for you but you must start out with setting for the largest clicks and progress to the smaller and smaller.

There have been cases of recordings so noisy that too many smaller clicks were masked by the background noise but became more audible after noise reduction. Therefore, at least some noise reduction before final declicking is sometime useful.

The Younglove process is quite often useful . I use four variations, depending on the recording. This should be the last step of automated declicking.

Noise reduction is next. Some LPs are fine without it but it is more often than not beneficial in my experience. This will depend very much on the music and the condition of the LP. I have found, contrary to much advice, that the same process can successfully be done on the entire recording  at once instead of doing each track, or piece of track, with its own settings.

Again, I often do more than one pass; two most frequently. Then, on some material, especially with significant fade in or fade out sections,  I may do one or more passes on just those sections.

Also, on particularly damaged or noisy recordings, one or more passes of the Younglove processing can usefully be applied for noise reduction, used on just those selected parts that need it.

I don't do EQ manipulations but if you are intent on that, this is the time.

Normalize for the last step, with one exception. Without arguing ay thing about the audibility of the quantization noise at different bit depths when there is musical content, the data is definitely different after processing operations. With simple test tones the differences are very obvious in spectral analysis and can be heard at higher volume levels.

I always record in floating point, then convert to 16 bit after everything else is done. I find no downside other than a slightly longer save file time. I've never been so bouncy excited that I can't wait for a save file operation to finish. I suppose that if every program I use did not produce an index file on record and Save As operations, file loading time might be a small issue.

Another suggestion is to produce a number of output files, one for each major step of processing (preferably with a naming scheme that identifies what was done). While the need is rare, if you find you don't like something after a new operation, such as NR, you can simply drop that file and go back to the previous step to try again. I never keep anything but the final output -- once the LP is totally finished, so those intermediate file take up disk space only temporarily.

  • Apesbrain
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #5
I always record in floating point, then convert to 16 bit after everything else is done.

Another suggestion is to produce a number of output files, one for each major step of processing (preferably with a naming scheme that identifies what was done).  I never keep anything but the final output -- once the LP is totally finished, so those intermediate file take up disk space only temporarily.
Agree on this.  My USB audio interface outputs 24-bit which I record in Audacity (with ASIO) using 32-bit float.  When all noise reduction and clean-up is done (for which I use some of the software OP has listed), I save the final work product as an Audacity Project file with all track splitpoints and tags, and delete all interim files.  This takes about 850 MB per LP and leaves me the original "master" should I ever have to go back for more edits or equalization.  The Project file is used to export tracks and those tracks are dithered to 16-bit, converted to FLAC, and ReplayGained using foobar2000.  Any tag touch-ups are done with Mp3tag.
  • Last Edit: 08 October, 2016, 02:59:24 PM by Apesbrain

  • greynol
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #6
I reject the commonly spewed FUD about quantization error caused by successive edits.
Since people have tried to tip-toe around this, I thought I would make myself more clear.  Any decent software will process at higher than 16-bit and then dither back.  This is not to say that there is something inherently wrong with keeping stuff at >16-bit and then reducing depth at the end (or not reducing the depth).  However, claims of better sound quality are indeed subject to TOS8.

Comparing test tones to real music, especially when played back at levels that will cause hearing damage with normal content isn't any less silly than riding gain on reverb tails in order to justify 24-bit content; actually it is worse because we're talking about a medium that doesn't even require the use of 16 bits in the first place.

I applaud Best PracticesTM, though I often have a hard time discerning it from voodoo.  This goes for all the masturbation over samplerate conversion as well, which, in light of other recent discussions on the subject, is likely why I continued on with this rant.
  • Last Edit: 09 October, 2016, 02:42:39 PM by greynol
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #7
Just my experience/opinion: If you digitize master with good 24 bit DAC, it is worth to keep the original Audacity project (if big editing/flagging was done) or keep just 24 bit FLAC of that recording as a master save (this is what I usually do especially if the edits/flags are minor). Subsequent distribution could then be typically in 16 bit dithered (or even in lossy formats if required) created from this master. Or you can keep tracks in 24 bit even for playback, if space is not concerned and further processing/dithering is not desired, but the benefits are rather theoretical (i.e. non-existent for common listener) and no audible differences were reliably proven through ABX testing (I am emphasizing this to be compliant with TOS and not start any flame). Also my experience from recent months shows that when I did home recordings/digitizing and gave them to my friends either in 24 or 16 bit FLAC container they did not claim a difference.
As for sample rate, 48 kHz is enough for digitizing/recording except for very special purposes/rare material.
Click removal works well for older/played vinyl, but sometimes it changes sound at those "declicked" places - depends on settings. Noise removal (for vinyl/tape) also works if neccessary but sometimes removes also part of the audio - again it is worth to try different settings for particular track/purpose and sometimes it is better to tolerate some noise than trying to remove it.

I use Audacity/MP3Tag chain. Works very well.
  • Last Edit: 08 October, 2016, 11:46:17 PM by jumpingjackflash5

  • cliveb
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #8
Since people have tried to tip-toe around this, I thought I would make myself more clear.  Any decent software will process at higher than 16-bit and then dither back.
When the source is LP, you don't even need to dither back. The inherent background noise level of vinyl is so high (-70dB is an *exceptionally* good figure and most LPs are typically about -55dB) that the accumulation of multiple 16-bit quantisation errors due to undithered edits is never going to rise anywhere near the (faithfully recorded) surface noise.

  • greynol
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #9
Agreed.

Of course more "theoretical" wanking can easily ensue:
https://hydrogenaud.io/index.php/topic,111298.msg917015.html#msg917015
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #10
First, high pass filter to remove low frequency turntable noise like rumble. Common filters roll off below 20 Hz. Few LPs of the ~ 800 I recorded and cleaned up had any content below 32 Hz. Often 40 Hz is a better choice.

Declick next. Noise reduction first will make it significantly more difficult to find (especially for programs to automatically find) smaller clicks and often harder to remove more obvious ones cleanly. I frequently do four or five passes of automated declicking, each with different settings, then do manual declicking on what I can hear. I use three basic settings for manual fixes. Since the settings depend very much on the application program, I can't suggest settings for you but you must start out with setting for the largest clicks and progress to the smaller and smaller.

There have been cases of recordings so noisy that too many smaller clicks were masked by the background noise but became more audible after noise reduction. Therefore, at least some noise reduction before final declicking is sometime useful.

The Younglove process is quite often useful . I use four variations, depending on the recording. This should be the last step of automated declicking.

Noise reduction is next. Some LPs are fine without it but it is more often than not beneficial in my experience. This will depend very much on the music and the condition of the LP. I have found, contrary to much advice, that the same process can successfully be done on the entire recording  at once instead of doing each track, or piece of track, with its own settings.

Again, I often do more than one pass; two most frequently. Then, on some material, especially with significant fade in or fade out sections,  I may do one or more passes on just those sections.

Also, on particularly damaged or noisy recordings, one or more passes of the Younglove processing can usefully be applied for noise reduction, used on just those selected parts that need it.

I don't do EQ manipulations but if you are intent on that, this is the time.

Normalize for the last step, with one exception. Without arguing ay thing about the audibility of the quantization noise at different bit depths when there is musical content, the data is definitely different after processing operations. With simple test tones the differences are very obvious in spectral analysis and can be heard at higher volume levels.


The above order of operations makes a lot of sense from a theoretical standpoint. Digitizing a LP is a multi-step process, and many of the steps are nonlinear.  Multi-step nonlinear processes are very old news and guidelines for tuning and sequencing them are well known among those who have specialized in such things.

The largest undesired signals and noise should be removed first to minimize the artifacts that any nonliniear processing stepts might add.

Many don't realize this, but if you measure the output of the cartridge, the largest source of noise at that point is usually LF noise from bouncing and vibration of the tone arm at 80 Hz and below. 

Next, impulse noise due to scratches and the like should be removed because they are usually the next smallest (or second largest).

Then comes tics and pops due to dirt. Finally, remove hiss, as is possible while retaining the best possible fidelity.

The smallest source of noise added by the LP, usually being hiss is still vastly larger then 16 bit quantization noise. Therefore even the oft-disrespected fixed point 16 bit operations are up to 4 bits or more overkill. 

Many vinylphiles aggressively circulated falsehoods and lies about imaginary audible losses due to 16 bit digital audio. Their punishment appears for them to be to waste time and money acquiring and using excessively numerically intensive approaches including high sample rates, excessive data word lengths,  and esoteric numeric methods.   Where are the DBTs justifying these methods? 

  • greynol
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #11
Has anyone ever subjected a 24-bit master of digitally edited needle drops to lossywav using aggressive settings?

...or how about...

Take two copies of a normalized 24-bit vinyl capture: reduce the effective resolution of one copy to 14 bits and leave the other copy unchanged.  Subject each copy to the same set of edits and ABX for differences.
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

  • cliveb
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #12
The largest undesired signals and noise should be removed first to minimize the artifacts that any nonliniear processing stepts might add.
Agreed - with one caveat. See below.

Then comes tics and pops due to dirt. Finally, remove hiss, as is possible while retaining the best possible fidelity.
For truly anal digitisers (like me) whose goal is a completely tick-free transfer, there's a slight issue....

As well as removing ticks and small pops, we also like to reduce constant background crackle. It may be that Arny would define this crackle as "lots of ticks" (which if course is what it is). But just to clarify, the removal of isolated ticks is a completely different process to that of reducing crackle.

Removal of isolated ticks without causing any collateral damage is best done manually, typically using a spectral view to identify them and then manually repairing just that tiny section of waveform (using interpolation, spectral substitution or waveform redrawing). This is a manually intensive process that takes quite a lot of effort to get right.

On the other hand, reducing crackle is probably best addressed by using the "Younglove" technique, and apart from the initial setting up, it's a largly automated process that doesn't involve a lot of effort.

Here's the issue: the Younglove technique often has a side effect of also removing some of those small ticks that would otherwise take you a long time to fix manually. But not all of them. So doing the decrackling first makes sense, because it can save you some of that de-ticking effort. Although the crackle is in principle a smaller undesired signal than many of the ticks, it makes sense to deal with them the "wrong way round", otherwise while you're de-ticking, you never know whether a specific small tick is going to be removed later by Younglove and can therefore be ignored.

Of course many people with a life don't obsess over this the way I do, and just whack the whole file through some sort of automated declicker. I envy these people who have better things to do with their time. Some automatic declickers even work reasonably well. (That's damning with faint praise, just in case you didn't notice).
  • Last Edit: 12 October, 2016, 06:04:05 AM by cliveb

  • Juha
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #13
...
Take two copies of a normalized 24-bit vinyl capture: reduce the effective resolution of one copy to 14 bits and leave the other copy unchanged.  Subject each copy to the same set of edits and ABX for differences.

Why would anyone record anything by his/her hearing skills? Aren't the question here about something else.

If there's a need for post-processing the vinyl recording wouldn't it be better to have it done at higher sample rate and bit-depth?

My work flow is:
For Reaper, I have created a 'base project' (24/96 recording) which has all the needed pre and post plug-ins (RIAA, FreeG (fine tune L/R balance and gain if needed), HP (<20Hz, rumble), LP (remove >20kHz), SPAN (metering) and Hum (50Hz/60Hz) remover) included but only
- FreeG is enabled in tracks' pre-FX slot,
Other plug-ins are placed as
- RIAA, HP, LP and SPAN in tracks' post-FX slot and
- SPAN enabled in FX slot of master channel

So, basically I have only L/R balance (and maybe levels) fixed in my archived recordings and those other effects are present only in rendered versions of the archived album (FLAC --> mp3). FLAC version is cleaned from pops/crackle by editing manually.

As Reaper saves all the states/settings of the plug-ins to its project file, I open the base project for each album and before starting to record the album just save the project using artist-album naming (..\<artist>\<album>\recorded and rendered file(s) stored here). I prepare time data for cue sheet by setting the index markers in Reaper (I have prepared an utility for to update the index00 time code fields of downloaded cue file).

Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #14
...
Take two copies of a normalized 24-bit vinyl capture: reduce the effective resolution of one copy to 14 bits and leave the other copy unchanged.  Subject each copy to the same set of edits and ABX for differences.

Why would anyone record anything by his/her hearing skills? Aren't the question here about something else.

If there's a need for post-processing the vinyl recording wouldn't it be better to have it done at higher sample rate and bit-depth?

My work flow is:
For Reaper, I have created a 'base project' (24/96 recording) which has all the needed pre and post plug-ins (RIAA, FreeG (fine tune L/R balance and gain if needed), HP (<20Hz, rumble), LP (remove >20kHz), SPAN (metering) and Hum (50Hz/60Hz) remover) included but only


Good approach and questions. But if you lowpass above 20 kHz then 24/48 would be well sufficient for your recording (as it is for 99,9 percent of other cases). Of course it is good to do the processing at the original rate/bitdepth and do possible dither/resampling to CD as a last step.

  • Juha
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #15
...
But if you lowpass above 20 kHz then 24/48 would be well sufficient for your recording (as it is for 99,9 percent of other cases).
...

You sure know the 'issues' when putting LP filter close the N frequency. If I want the digital LP filter to work as like an analog filter would do, using high sampling rate is one possible (and easy) way to fix the issues and the other way to go would be the implementation of the digital filter itself. In my case, I have implemented the LP filter to work without aliasing/warping (just as the analog LP filter does) at any sampling rate so this way I could have the sampling rate lower than 96kHz but, AFAIK the other filters I'm using might work/works better at higher sampling rates.

Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #16
I know 44.1 can be/is tight for filtering without aliasing but at 48 kHz 4 kHz filtering space is not enough for you ?
  • Last Edit: 13 October, 2016, 06:11:34 AM by jumpingjackflash5

  • greynol
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #17
...
Take two copies of a normalized 24-bit vinyl capture: reduce the effective resolution of one copy to 14 bits and leave the other copy unchanged.  Subject each copy to the same set of edits and ABX for differences.
Why would anyone record anything by his/her hearing skills?
If I were at all suggesting that then I wouldn't have gone so low; rather I'm assuming the SNR bottleneck is related to the media, not the skills of the listener.   I definitely didn't suggest that recording be done at a specific samplerate or bitdepth anywhere in this discussion, either.  Rather, this is about whether there is any veracity to the assumptions that maintaining a "hi-res" copy is necessary for editing; or if it is largely (if not solely) predicated on things like myths, FUD and placebo.

If there's a need for post-processing the vinyl recording wouldn't it be better to have it done at higher sample rate and bit-depth?
While I get the impression you think it's only rhetorical, I see this as a very legitimate question and propose that it be tested.

...and in case my previous comments have been overlooked:
This is not to say that there is something inherently wrong with keeping stuff at >16-bit and then reducing depth at the end (or not reducing the depth).  However, claims of better sound quality are indeed subject to TOS8.
  • Last Edit: 13 October, 2016, 10:45:31 PM by greynol
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

  • greynol
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #18
I know 44.1 can be/is tight for filtering without aliasing but at 48 kHz 4 kHz filtering space is not enough for you ?
People might consider whether content that has been low-passed at 17kHz can be ABXed before worrying about not having enough room for a transition band.
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

  • Juha
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #19
I know 44.1 can be/is tight for filtering without aliasing but at 48 kHz 4 kHz filtering space is not enough for you ?

Here's an example (Octave) plot comparing biquad IIR LP filter (cutoff frequency is 20kHz) against analog prototype and matched 4th order IIR filter at 3 different sample rates.

(BLT (pw) = Bilinear Transformation with prewarped fc, plot shows up to fc)

Analog prototype and matched filter there has equal frequency response up to fs/2 no matter what sample rate is used. See below the nature of the output of BLT based filter compared to the other two.

People might consider whether content that has been low-passed at 17kHz can be ABXed before worrying about not having enough room for a transition band.

Doesn't this depend on filter implementation ?

  • greynol
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #20
Doesn't this depend on filter implementation ?
Of course and you've made that plainly obvious. :)

I don't recall all the details of the discussions that capable members went through in order to satisfy this basic curiosity over a dozen years ago, though I also don't recall there being much fuss made over it, either.  I do think these tests are still important and revealing, and, unfortunately, also largely unknown to new members, if not simply taken for granted.
  • Last Edit: 13 October, 2016, 06:22:21 PM by greynol
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #21
I have only limited experience with filtering (one year), but I wonder why IIR filters (which for sure have their significance) are shown as an example if FIR filters are often used today, e.g. with SoX sinc effect and there transition width 2-4 kHz is common, in some threads here a preference for even steeper FIR filter like -b 99 was given.

Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #22

People might consider whether content that has been low-passed at 17kHz can be ABXed before worrying about not having enough room for a transition band.

Doesn't this depend on filter implementation ?


Aren't the limitations of the human ear also relevant?

Of course they are.  I am fascinated when people start pontificating about filter types and slopes, illustrated with nicely drawn FR curves from theoretical simulations, and completely and perhaps conveniently forget to do any DBTs,

Above we are presented with two frequency response curves, The supporting text seems to take it as revealed truth that they are distinguishable in an ABX test.  This might be so, but is the reason for the differences  above or below 10 KHz?

  • Juha
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #23

Aren't the limitations of the human ear also relevant?

Of course they are.  I am fascinated when people start pontificating about filter types and slopes, illustrated with nicely drawn FR curves from theoretical simulations, and completely and perhaps conveniently forget to do any DBTs,

Above we are presented with two frequency response curves, The supporting text seems to take it as revealed truth that they are distinguishable in an ABX test.  This might be so, but is the reason for the differences  above or below 10 KHz?


(where RBJ = http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt, 1e+4rad/s = 1591.55Hz, 1e+5rad/s = 15915.49Hz)

I don't mind to do DBT but, here are the coefficients for those various filters shown in plot if someone wants to run ABX test:
fs = 44.1kHz
fc = 17kHz
Q = 0.707 (= BW=1.900)

Analog prototype:
11409262687.6593
1.0 151080.8348261004 11409262687.6593

Various RBJ paper implementations:
Case Q [ 0.8760666490683719 1.752133298136744 0.8760666490683719 1.466061529573591 1.504266596273488 0.533938470426409 ]
Case BW [ 0.8760666490683719 1.752133298136744 0.8760666490683719 2.691575899010475 1.504266596273488 -0.6915758990104754 ]
Case Q + prewarped Q [ 0.8760666490683719 1.752133298136744 0.8760666490683719 2.023192926460408 1.504266596273488 -0.02319292646040805 ]

Filter which is matched to the analog magnitude response
Matched 2nd order (MIM) [ 0.8359412478697531 0.1948669448559074 -0.112155492262995 1.0 -0.03000145304555539 -0.05134584649177911 ]

If you use EqualizerAPO then just copy lines from code block to the config.txt (! ON/OFF states)
Code: [Select]
Filter: ON IIR Order 2 Coefficients 0.8760666490683719 1.752133298136744 0.8760666490683719 1.466061529573591 1.504266596273488 0.533938470426409
Filter: OFF IIR Order 2 Coefficients 0.8760666490683719 1.752133298136744 0.8760666490683719 2.691575899010475 1.504266596273488 -0.6915758990104754
Filter: OFF IIR Order 2 Coefficients 0.8760666490683719 1.752133298136744 0.8760666490683719 2.023192926460408 1.504266596273488 -0.02319292646040805
Filter: OFF IIR Order 2 Coefficients 0.8359412478697531 0.1948669448559074 -0.112155492262995 1.0 -0.03000145304555539 -0.05134584649177911
  • Last Edit: 18 October, 2016, 07:52:09 AM by Juha

  • greynol
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Re: Vinyl Ripping Workflow Suggestions Appreciated
Reply #24
http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt

I don't mind to do DBT but, here are the coefficients for those various filters shown in plot if someone wants to run ABX test
Why is the focus on simulations of analog filters?

For me this was about whether post-processing needs to include ultrasonic frequencies and whether there is a need to keep a master that includes ultrasonic frequencies.  I made no requirement that content must be filtered in the analog domain prior to digitization.
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?