Currently Being ModeratedFeb 1, 2012 1:51 PM (in response to JiminMissouri)
Correction: The description I gave for DC offset in my original post is totally wrong. In essence, if you look at a waveform and it's shifted off the null line, that's what DC offset does. So if you are looking at what is supposed to be silence and it's not on the null line - there you go.
Turns out I did not have this problem at all. The Macbook Pro's sound card is fine in this respect. What I thought was a DC offset problem turned out to be turntable rumble below 20Hz, most beloe 10Hz. For some reason the DC offset remove filter in Audacity was taking a lot of this out, which just added to my confusion. I'm currently using the Apple LowShelfFilter in Audacity to remove the low-end noise.
Also, my workflow has changed in the past month. I now record 96/24 in Audacity (though I understand I might not really be getting it). I run the LowShelffilter, then export a 24 bit AIFF, which I run through Clickrepair. The cleaned up file is moved back into Audacity, where I break it down into individual tracks. Those tracks get exported as as 24 bit AIFF, which are then added to the iTunes library, with iTunes Match turned off. I then create 256 AACs of the AIFF files, delete the AIFFs and turn on iTunes Match.
Currently Being ModeratedFeb 1, 2012 2:25 PM (in response to JiminMissouri)
Audacity has a bug in Windows where it will not record in 24-bit, even if you set it that way. It's allgedely due to DirectSound, but I believe there are workarounds. Linux/MacOS should not have this problem. Also, if your line-in doesn't support 24/96, you might think you're getting 96khz but in reality it's just dead space.
Here's a spectrogram of what I see with my GT40 recording (which does do 24/96 in):
-96db is the 16-bit limit. Notice the slow drop down, which I believe is the expected behavior. When I was doing with a line-in which did not support true 24/96, I would get spikes over 22khz, but it wasn't a slow drop like this. I believe those spikes were just noise and not actual musical data.
I also use the free and cross-platform tool called "Spek" to get a better picture of this. It will show the spikes better than you'd see in the Audacity spectrogram tool.
Currently Being ModeratedApr 3, 2012 6:29 PM (in response to Mike Douglas1)
Wanted to post a small update to my vinyl matching - had a small breakthrough that some may find of interest.
I recently upgraded my stylus to a Nagaoka MP-110. I usually attempt a iTunes Match with every needle-drop I do, and I actually re-dropped an old probematic LP where I got a 4/9 Match, back in January. Interestingly, I just tried to re-Match with this new drop and I got a 6/9 this time. This new cart of mine has two specific differences from what I've used before -- first, it's generally quieter (less surface noise) and secondly it's a more "neutral" sound. In other words, it may sound more like what's in iTunes.
Just something to think about with your own needle-drops -- the closer you an get to the sound of the iTunes files, the more likely you'll get a Match, imho.
Currently Being ModeratedApr 24, 2012 6:34 AM (in response to jonathanfrommankato)
In iTunes, select "View Options"
From the "View" menu, and check "iCloud Status". You'll find each item in your library listed as Waiting, Uploaded, Matched, or Ineligible.
Uploaded items are songs that weren't Matched, but are
Uploaded to "iTunes in the Cloud" and are available to
Download on any device connected to that iCloud account.
Ineligible items are iTunes Extras, Voice memos, etc.
Hope this helps. More info is available in Apple support article TS4124
Posted from my iPhone 4S
Currently Being ModeratedJun 7, 2012 11:04 AM (in response to roebeet)
Just wanted to jump in here and say thank you to you guys for a very informative discussion. I recently started playing with iTunes match in the hope I could short circuit some of the time-consuming activities in Audacity when it comes to digitizing my vinyl.
So far I have digitized 16 albums and only 6 tracks matched (sorry didn't count the total tracks). I was hoping to be able to match because the sound quality of my rips (using a cheap USB turntable) are awful. The frequecy response is way off and the wow and flutter is very evident. So, picked up ots of toips from you guys there.
I now have my B&O turntable repaired so I'm hoping for betting quality rips, and matches, going forward. Interesting comments on the space at the beginning of the track, but if I have nothing to compare it to how do I know the optimum value? (i.e. in the space between tracks when does one track end and the next begin?).
Very interesting comments on the Audacity click filter, looks like I need to be trying ClickRepair - and TuneUp as well.
Currently Being ModeratedJun 7, 2012 12:15 PM (in response to amigasteve)
I was using Rhapsody (which I subscribe to) for the silence / pitch matching, but you could probably try Spotify for a "free" solution.
Silence before/after is definitely pretty key, from my experience -- I've definitely tweaked that not only for vinyl rips but also CD rips where I might get a match after I tweak it. I also use the iTunes track times as a guide - you want your vinyl track to get as close to that as possible.
Currently Being ModeratedJan 22, 2013 2:19 PM (in response to Mike Douglas1)
Hey folks, I realize that this thread is kind of old, but I just encountered something I hoped y'all could help me with. The White Stripes's album Icky Thump is on the iTunes Store, and I have it, but Jack White's record label has a record club where you get limited vinyl every quarter, and their first issue included a MONO mix of the album Icky Thump. It only exists on vinyl and is fairly rare, so I was hoping to digitize it and have it upload to iTunes Match. The first two tracks matched, and the rest uploaded. I was hoping it would upload it all, because the things it matched to are the STEREO tracks from the iTunes Store, which i already have in my iTunes library.
How do I force iTunes Match to recognize these as tracks that are new, rather than tracks that the store already has?
Currently Being ModeratedJan 22, 2013 2:51 PM (in response to aaronmchidester)
Pretty much the reverse of what I suggested earlier in the thread - possibly add a few seconds of silence at the start of each track, for example. Or, tweak the pitch levels a bit. There's a good chance that one or the other will allow for an upload vs a Match.
Currently Being ModeratedFeb 25, 2013 1:56 PM (in response to roebeet)
Roebeet, been a long time since I checked the forums. A quick scan didn't bring up much new on the subject, so below is my latest. Forgive me if it's old news to some.
To date, I have submitted to iTunes Match approximately 325 albums recorded digitally from vinyl, all recorded with iTunes Match in mind. That's about 2,900 tracks, 1,442 of which matched.
At first glance, that doesn't sound all that great, but a few factors have contributed to my overall track record being significantly lower than what I've achieved of late, most of which we've covered before: (1) songs, entire albums just not in the store, (2) experiments that simply made things worse for a time, etc.
The short story is I believe the better matches I'm getting now (95%-100%) come down my shifting focus to removing noise from the tail of the track, including the silence left on it, although other factors we all covered some time back certainly matter.
I believe the matching process needs to be able to sync to the track tail and anything that prevents that from happening, prevents a match. Further, the actual sample matched seems likely to be in or near the tail, as since I've shifted focus to the tail, I've been able to get matches for some tracks that had a fair amount of unrepaired damage early on (which I either repaired later or decided it best to trash my file once I had a good match).
To accomplish this I am still using ClickRepair, but applying break points to allow me to adjust settings differently for the main part of the track, for the tail, and finally for the silence.
After having reviewed "damage" flagged by ClickRepair down to an auto setting of 6, I've concluded that for far too many well recorded albums in good condition (true vintage albums with poor dynamic range & more narrow frequency response are a different matter), more music is being lost than damage repaired. In some cases, having the repair setting at 1 and still watching any proposed change over 6, I still see far too much music being removed.
Therefore, I often turn off processing for the body of the track, run in manual for the remainder, until it's clear noise amplitude is well above the music and ClickRepair is making good decisions on its own. Once I'm there I, put ClickRepair to 100 and full Auto. It then does its thing quickly and stops at the beginning of of the next track
With respect to the concept of iTunes Match needing a clean tail in order to sync, consider what happens in Audacity if you try to use the "Silence Finder" as a means of placing label markers at the beginning of each track. It works - so long as there isn't something in the silence that rises above the threshold amplitude level. One little nit above that threshold and the label is either mis-placed or an additional label is put right before the nit. As for why the tail and not the head, the fact that the tail of a track is usually only available to someone who has the full track (previews I'm aware of don't include the tail), plus the need to obtain and verify track length through means other than metadata are relevant.
Putting your own fade out over the original, followed by inserting true silence is a mixed bag. Putting aside the fact it ruins the continuity, the feel of the vinyl recording, you run the risk of altering the tail enough to cause matching problems. It can help if one wants to go that route, particularly on tracks that are so noisy ClickRepair just can't quiet things down below whatever threshold iTunes Match requires. In my experience it will improve your matching percentage, but I didn't find it to be as effective as what I'm doing now, and as I said, it's not something most of us want to do anyway.
With respect to the other side of the discussion, working to force uploads, all you've said still seems on target. My guess is if someone really wanted to force an upload, based on my current understanding, placing a simple, soft click or any more subtle, pleasant noise shortly after the tail ought to do it. My guess is if it's loud enough to trip up Audacity's silence finder, it will trip up iTunes Match. Not optimal, but then short of the magical force upload button suddenly appearing, nothing really is.
There's a lot more to my current process, which I'll be glad to explain if anyone is still interested in the subject.
Currently Being ModeratedFeb 25, 2013 7:32 PM (in response to JiminMissouri)
Nice post! I personally haven't delved into it too much since early 2012, although I did renew iTM as I had a gift card to burn and I figured a few $5 Amazon purchases would basically "pay for itself" for the year.
I actually need to try a recent vinyl rip of mine, in that I tried the MP3 download (Joy Formidable's "Wolf's Law") and got only one match. I think it's related to "Mastered for iTunes" and matching, but that's a different discussion. I've also since moved onto another turntable with less rumble so that might actually help with matching as well.
Currently Being ModeratedFeb 25, 2013 8:44 PM (in response to roebeet)
I agree that a reduction in rumble or anything else that just wouldn't be in the iTunes version could improve matching. To that end for a time I was using the Apple Low Shelf filter in addition to the rumble filter on my preamp to knock down everything in the 10-20hz range. I was never able to verify that it mattered for matching (tried some problem tracks both ways and nothing changed), but felt it was the right thing to do for my rips anyway. However I also believe that it's one thing to keep low frequency from ever hitting the sylus, quite another to remove it after the fact. I suspect once its hit the stylus, the low frequencies alter the music in a way that filters simply can't counter. Wouldn't surprise me if this was heavily documented by audio engineers in the middle of the last century.
While I've not moved from my Dual 1219, I have made some simple changes that have knocked down rumble to the point where using the Low Shelf Filter is no longer necessary. One day perhaps the rumble filter can be removed from the equation as well. In any event, placing some damping material inside the plinth helped quite a bit, as has using a center weight. It's certainly possible that if I had not made those changes, I never would have discovered that processing tails and silence could make or break a match.
I recall there was some discussion regarding whether it was possible to match vinyl to albums only available as remasters in iTunes, though the discussion focused on Beatles tracks.I can confirm that in some cases vinyl will match with remasters (other than Beatles). I got a 100% match last week to Johnny Hammond's Wild Horses Rock Steady which is onlly available as an anniversary issued remaster. Apparently the original KUDU holds up pretty well after all these years.
Currently Being ModeratedFeb 25, 2013 11:59 PM (in response to JiminMissouri)
Like you I have had good success matching vinyl rips.
I use project turntable with built in analog to digital converter and connect by USB to my mac. Audio hijack pro is used to capture record as 24 bit AIFF files.
I use Denoise LF at default settings, then Click repair to decracle, then again to de click. I then use Denoise at default levels.
I then edit track in Audacity to get track to be the same length as store version and use normalise function. Sometimes use click removal or repair to fix tracks that Click repair missed.
File is exported as Aiff and added to iTunes. This format along with lossless appear to be causing problems in latest version of iTunes but that is another story.
Do you have any suggestions to help me improve match process, specifically the settings on Denoise and Click Repair.
Currently Being ModeratedFeb 26, 2013 7:04 AM (in response to JiminMissouri)
Jim, I'm 3 hours north of you, in Des Moines, IA. I haven't done much more matching since last Spring, but that stack of unripped vinyl has been calling to me, of late. Although I've had reasonable Match success, I know that it could be much better. I'm not an audio guy. And, while I get a lot of what's being talked about, there's more that I don't understand, and there are methods being talked about that I don't understand, and software that I don't have/have never used. Is it possible (and would you be interested in) to take a discussion offline to real time? Like hauling my setup down and doing a rip session together? B lehn ertz at me