DeNoise vs. Aud 1.3.12 Noise Removal

[khoffcran]

Thanks to all who got me onto 1.3.12 and suggested Brian Davies' ClickRepair for vinyl sound restoration. It's re-opened portions of my vinyl collection (about 2,000 LPs) that I thought were gone forever. As to the effectiveness of ClickRepair, I thought Wax might have been exaggerating when he called its results "...little short of magical." In fact, my preliminary results have demonstrated that his endoresement was instead typical British understatement. I'd put it on the north side of magical.

New question: Should I start into the complicated process of blind A/B tests for comparing Davies' DeNoise and DeNoise LF vs. Audacity 1.3.12 noise removal, or is there already a pretty clear consensus among users that either is clearly superior to the other? (Or, in the alternative, that the difference is marginal and not worth the time / cost for DeNoise-DeNoise LF).

Thanks for all your help,

Keith H NJ / USA

P.S. - On the downside, all the work I've done so far is now obsolete. And after I've loaded my results into iTunes, I've destroyed my original raw files to save space. Maybe my next investment should be a 2T external HD, dedicated only to saving raw .aup files against the possibility of future game-changing technology leaps.

[bgravato]

P.S. - On the downside, all the work I've done so far is now obsolete. And after I've loaded my results into iTunes, I've destroyed my original raw files to save space. Maybe my next investment should be a 2T external HD, dedicated only to saving raw .aup files against the possibility of future game-changing technology leaps.

I'd not recommend using audacity projects as the best format for storage. WAV or FLAC is preferred. Audacity projects are splitted saved into hundreds of small audio files and one text .aup file. That speeds things up when editing in audacity, and also saves some valuable extra information, so it's good for WIP (work in progress) projects. But those hundreds of tiny files are not good for storage, that can arise a large number of issues. So for storage I'd recommend saving it all in one (lossless) file.
The most compatible option is WAV, that's the standard format for uncompress audio, you'll be able to read that in any system and audio player. The disk-size optimized option would be FLAC. It will reduce file size to about half while keeping the audio undamaged. The disadvantage is that not all systems/players will be able to read those files without installing extra plugins/codecs.

My recommended safest workflow would be to save a copy in WAV or FLAC right after recording, before any editing done. Then save another WAV or FLAC copy after all the editing. Keep those two files.

[waxcylinder]

Keith,

I totally agree with bgravato that you should be saving WAVs rather than auidacity projects. You could choose to save 32-bit WAVs as the best quiality - personally I save and backup 16-bit downsampled WAVs for my archive (I also plan to use them as audio files later if and when iPods get very big storage - at least 1TB v. the cirrent 160gB max).

a 2TB disk - really you will need 2 x 2TB disks - you need to keep at least two copies of the data for safety. One of my big hard-drives failed last year (was I glad of the second copy then that I had).

2,000 LPs - thats a lot of work - I spent 2 1/2 years doing 250 of mine (I'm currently working through 300 of my wifes's LPs). I currently recon I could do a max of about 4 to 5 per day and means doing little else - and my workflow is now pretty slick.

Without doing the math I'm not sure that a 2TB disk will be big enough, particularly if you save the raw recorded WAV as well as your production WAVs as bgravato suggests. But never mind beacause by the time you near the end of this project disks (or other storage) will be much bigger and much cheaper

I tried Brain's DeNoise on an old blues set of albums that I had which were obviously transcribed from shellac 78s and done before tha age of digital editing. DeNoise worked quite well on those, but it was nowhere near as simple to use as ClickRepar - I haven't bothered to buy the license - If I had a lot of 78s to work on then I would, but for my vinyl LPs it didn't seem worthwhile.

WC

[steve]

A 2T drive has more than enough room to store your entire vinyl collection in WAV format.
2 drives would offer some protection against one of the drives failing.
It's going to take a long time to digitise 2000 albums, so if the budget is tight you may not need to buy two really big drives now. By the time you get up to 500 albums the cost of 2T hard drives will probably have come down.

The Noise Removal in Audacity is one area that could benefit from substantial developer attention. I use "Gnome Wave Cleaner" (on Linux) which is considerably better than the Audacity Noise Removal effect, but I still prefer to use it as little as possible. All de-noise effects cause some degree of damage to the audio and it is very easy to cause more harm than good. Any damage done with Noise Removal is irreparable.

I'd recommend making your archive copy with no "Noise Removal" (use the ClickRepair if you like).
You can always use Noise Removal on your iPod copy.

[khoffcran]

Thanks.

Why do you all seem to prefer saving as WAV rather than AIFF when working with Macs? Isn't AIFF native to Mac (and so presumably more compatible) or does that not matter in this context?

KH NJ / USA

[khoffcran]

Oops. I also meant to ask this:

For those who believe vinyl (with the right analog TT and cartridge) has a "warmer, richer" sound than CD - Is it because of the original analog recording and mastering process? Or does it have to do with the final product medium.

In other words, by cleaning vinyl through software and digitizing it, are we not introducing the flaws that vinyl-philes detest? That's not really a philosophical question as much as a practical one. I suspect that the perceived "warmth and richness" of vinyl have to do with the original recording and mastering process. If that's the case, and the final product we produce in this process is merely a perfect duplicate of vinyl as played on a top-notch analog TT with a first-rate cartridge - and then cleansed of its extraneous surface noise by Professor Davies - isn't this the best possible reproduction of the original sound?

Or, perhaps, do you suspect - as I do - that almost no audiophiles or even musicians could differentiate between a CD and (clean) vinyl in a blind A/B test?

Keith H NJ / USA

[steve]

Macs have no trouble with "stereo 44.1 kHz 16-bit (Microsoft) PCM WAV" files.
That format is the most universal audio format there has ever been and is recommended on all platforms because of its universality.

Regarding Vinyl vs. CD.
In England there are strongly held views about how to make a proper cup of tea.
The "purists" will argue that it must be made in a pot with high quality "leaf" tea. That the pot must first be warmed with boiling water. That a precise amount of tea is used and the pot is not over filled. That it is left to stand for a prescribed amount of time. There may be robust arguments about if and when the pot should be stirred, the type of cup that should be used and other details, but of course the milk goes into the cup before the tea.
Personally, I can tell the difference, but I prefer my tea made with a tea bag in a mug.

[kozikowski]

Audacity defaults to Microsoft WAV format because it's unquestionably recognized by all three computer platforms. Try to play an AIFF on a Windows machine.

"Here. Let me email you my sound file ....oh, wait."

The quality of the music is exactly the same, but AIFF allows (I believe) additional metadata and song information missing from the WAV standard.

Is it because of the original analog recording and mastering process?

Yes. The trip through analog mixers and ribbon microphones, analog audiotape and multi-channel mixdowns doesn't always produce evil distortion. Sometimes it produces a pleasant warm rich sound which is why people still use vacuum tube amplifiers.

And yes, it is distortion.

Koz

[bgravato]

Yes. The trip through analog mixers and ribbon microphones, analog audiotape and multi-channel mixdowns doesn't always produce evil distortion. Sometimes it produces a pleasant warm rich sound which is why people still use vacuum tube amplifiers.

And yes, it is distortion.

Koz

I was thinking about exactly the same... Some ppl do prefer vacuum tube amplifiers and some even say that its sound is less distorted that with transistors. Mathematically that's not true, vacuum tube amplifiers introduce a lot more distortion into the original signal than transistors. On the other hand seems that the human ear is less sensible to that kind of distortion than it is the transistor's kind of distortion.

And it also happens that some ppl claim that A is better than B just because...
Those are the ones that in a blind test end up choosing B over A and then try to find silly excuses for it their "erroneous" choice.

Regarding WAV vs. AIFF, I prefer none... I prefer FLAC! FLAC doesn't damage the audio, still it produces files half the size of WAV. For Mac users the online drawback about FLAC is that is doesn't play (out-of-the-box) in iTunes (I think that can be fixed), which isn't a problem to me at all since I don't use iTunes (my favourite music player on Mac is VLC). And by the way, my primary OS is Linux, not Mac (Mac is the secondary and Windows is live-happy-without-it )

I also plan to use them as audio files later if and when iPods get very big storage - at least 1TB v. the cirrent 160gB max

That's two of the reasons why I love Sandisk's players:
1) they let you put memory cards in it (for virtually ilimited storage capacity)
2) they can play FLAC (virtually doubling the capacity)

And according to some reviews and tests they have the less distorted output (and they are cheaper than ipods).

Regarding the disk storage, I currently have a NAS server (DLink DNS-323) with two 1TB disks in RAID-1. NAS servers are network file sharing unities. RAID is a system in which you mirror the same information in two (or more) disks, if one fails you replace it and the data gets mirrored again automatically. Being networked units you can access files in it from any computer in your home network.

[billw58]

Keith:
And now for another opinion ...

I save and archive Audacity projects. I also archive FLAC copies of each LP side before processing. So ..
0) I work in 16-bit 44100. I don't believe my old ears can hear the subtle differences in processing artefacts in 32 versus 16 bit.
1) Record LP side 1, export as AIF, delete track in Audacity, record LP side 2, export as AIF, delete track from Audacity.
2) Process AIFs with DeNoiseLF
3) Process those AIFs with ClickRepair. Sometimes twice: first for ticks and pops, second for crackle.
4) Sometimes process those AIFs with DeNoise. I usually go for a maximum of 9 dB noise reduction.
5) Import the final processed AIFs back into Audacity, edit, amplify, mark tracks, edit metadata, export multiple as AIF. Save that project.
6) Drag and drop exported AIFs onto iTunes and convert to MP3 (256 kbps VBR) in iTunes. Delete imported AIFs from iTunes library.
7) Compress the unprocessed AIFs to FLAC using Max (to save space). http://sbooth.org/Max/
8) Delete the AIF tracks (that were imported into iTunes).
9) Delete all the intermediate files generated by DeNoiseLF, ClickRepair and DeNoise

If I need to recreate the uncompressed tracks I can export again from Audacity.
If I want to start over with processing the LP, I can convert the FLACs to AIF and start over with DeNoiseLF, etc.

The advantage of AIFs for Mac users is that they properly store metadata, and iTunes reads it. So before export multiple I do File > Open Metatdata Editor and set the Artist, Album Title and other common fields for the LP. Then when I do export multiple Audacity uses the label text for the Track Title and the label position for the Track Number tags. iTunes reads these properly and transfers the tags to the MP3s, often correctly identifying the LP and fetching the art work from the iTunes store.

IMO the Noise Removal tool in Audacity is no match for DeNoise. There was an extensive debate about this a few months ago, and I'll try to find the thread. I have an old and hissy recording (early 70s) of solo acoustic guitar that suffers from tape hiss. The Audacity NR tool could not take out the hiss in the decay of the guitar notes without warbling the guitar notes. DeNoise could.

DeNoiseLF uses a completely different approach to removing noise than is used in DeNoise or the Audacity NR effect.

-- Bill