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R/E/P => R/E/P Archives => Brad Blackwood => Topic started by: Level on April 26, 2005, 09:35:15 AM

Title: A cool exersize of skills and opinions.
Post by: Level on April 26, 2005, 09:35:15 AM
For topic number 666, we have an excerise to perform.


This track came off of an old tape. The bottom sounds out of phase and the bottom spread is 270 degrees wide. Obviously, the entire song was really not "wired" correctly in production.

This is old.

If you want to take a crack at mastering this, would you:

Change bass phase
Leave it alone and noise reduce, try to tighten it up.
Pass on it.
Do your own thing!

Here it is...

Just an example of restoring.

Anyone got time off to look at it, it could be a fun thing to see what others would do with it.



Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 26, 2005, 10:56:20 AM
Damn, Bill. My commiserations. Eek.

I'll fix it- are we supposed to be doing stuff with the crappy mp3 or are you putting a complete file up somewhere?

I can't fix the musical quality Wink

Don't know about the bottom spread (NNTAWWT Very Happy )

I can de-splat it for you some if you like, and un-tapeify that crazy uber-phase-shift-and-head-bump. Yikes. This is not typical of what you have to deal with I hope Bill?

It's a little hard to explain- easier to show. I wonder if Brad (if his server was up) would care to have people publically doing a shootout on a trainwreck this scary? Very Happy

Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 26, 2005, 12:31:49 PM
I do these all the time to stellar quality...go for it..

This is my Niche, see what you think. I am simply trying to educate here...and be educated all the while.

It gets much worse, this one is rather simple.


PS, you will never on a blind test, tell the difference from my MP3's and wav. No one, not even me, has done so.

You get what you got.
Title: Re: A cool exersize of skills and opinions.
Post by: PookyNMR on April 26, 2005, 02:47:49 PM
Bill, could you give an example of how well you were able to clean it up?

Thanks.

Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 26, 2005, 03:54:22 PM
Level wrote on Tue, 26 April 2005 12:31

PS, you will never on a blind test, tell the difference from my MP3's and wav. No one, not even me, has done so.

You get what you got.



*g* this works out to be a bit over 192K bit rate. Are you joking? I can do about 320K blind given a suitable sound like castanets. mp3's artifacts are pretty characteristic. I do have MacABX handy (I ported it) and could test that assumption for you- but then I think quite a few people could test it for you. I see you're using VBR but it's still mp3- not unlike using a FFT-based equalizer, which also can produce unappealing colorations in subtle ways

So you'd like to see me convert the mp3 into typically a 16 bit file, do stuff, presumably convert it back into mp3 again, and put it up against your stuff done from the original capture?

OK. Won't be able to host the file for long but I'm game. I'm remembering how you objected to the mp3 source on the Vida Loca shootout. Of course that wasn't really higher than 192K bit rate and yours is, for what it's worth.

I'd like to see your result, though Smile

Title: Re: A cool exersize of skills and opinions.
Post by: bblackwood on April 26, 2005, 04:17:14 PM
Level wrote on Tue, 26 April 2005 11:31

PS, you will never on a blind test, tell the difference from my MP3's and wav. No one, not even me, has done so.

Not even you?

Go ahead and post your results, Bill, for the class to hear...
Title: Re: A cool exersize of skills and opinions.
Post by: Allen Corneau on April 26, 2005, 04:59:19 PM
Ok, here's mine.

I centered up the bass a bit, clarified the vocals a little, and removed a touch of the "fuzz". I tried to do the most I could but still retain as much of the original intentions of the mix as possible.

Not great, but look at the source material! (That's not a slam on the MP3, by the way! Razz )

Allen
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 27, 2005, 01:13:12 AM
I'm a naughty little ME- instead of working I hung out with my fiance, went out for dinner and watched a bunch of South Park episodes on videotape  Very Happy

I _did_ get a start, but I expect I'm going to have to work hard to measure up to Allen's try. One thing: it's hardly fair to mention noise reduction when you don't supply a single second of ordinary noise floor without basses and DX7s and things droning away. However, de-smash did some good.

I was shooting for 'very improved' but am struggling- I can get the spatial qualities rather better but it sounds rather similar to the initial moosh. Tomorrow I'll see what I can finish up, and post something.

I'm very interested in how stellar Bill is making this- not least because I'm curious how much 'bass phase' alterations can help it. In fact I'm wreaking havoc with phase relationships myself, but not in a context of stereo width- so far I'm leaving the stereo image as mixed. We'll see if that's acceptable.

Until tomorrow....

Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 27, 2005, 09:29:54 AM
Real busy today. Allen, you did a really nice job there. When I get back to the studio computer, I will post mine. My day is full ..today and most of tomorrow.
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 27, 2005, 05:02:16 PM
Am I right that you guys like it really rolled on the top? I guess I'm bringing up some noise with this- if I had access to the actual tape I'd have grabbed a moment of music silence to get a snapshot of the background noise, and gated that slightly- like -6db or so.

I still wanted a lot of that stereo bass, but I toned it down quite a bit, manually turning the track into mid/side and going after the bass separately in side. In mid I kinda turned up the bass, but with a hell of a steep notch somewhere around 200 hz. Could have done with my usual habit of EQing to a turn and then setting the range to half what it was- there was no room for further tailoring in my own software, and there could have been. I hit the dense tapey saturation with 'remap' and expansion, and shifted the group delay around with nefarious intent (woofy midbass forward, ironically, because I couldn't get any body on the voice- super highs forward, mids and super lows back)

I'm sure there are even more stellar things to do with this trainwreck but this is what I was up to, today. And I'm curious if I'm driving people up the wall with the highs. I just could not resist bringing them out  Very Happy if it sucks, somebody say so. I thought the track was horribly dull and rolled-off.
Title: Re: A cool exersize of skills and opinions.
Post by: Lee Tyler on April 27, 2005, 10:14:51 PM
Here are my unproven, untested, detested "skillz".  Rolling Eyes This exercise has definately increased my "shits and giggles" factor for a bit of time this evening. Thanks!

Lee the Impaler
Title: Re: A cool exersize of skills and opinions.
Post by: Allen Corneau on April 28, 2005, 09:57:54 AM
I just sat down and listened to all four versions so far, and here's my critique (read: personal opinion! Twisted Evil )

CJ: You've got the best mono compatibility of the bunch, but perhaps to the detriment of the original intent. The mix seems to be changed the most out of the three.

Lee: Yours still has a lot of out-of-phase bass, but the eq seems like a good compromise between the source and what it "should" sound like (whatever that is!?!) It seems to have a bit of comb-filtering going on, but not sure where.

Allen (aka: me): I think compared to the others I could have gone a bit farther with the eq'ing, but I feel like I stayed closest to the original 's intent.

Now, I know it's biased to critique your own work compared to others, but I think it was an interesting exercise. I'm looking forward to hearing y'all's critiques, too. (Did I mention I'm from Texas? Very Happy )

Allen
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 28, 2005, 01:25:17 PM
I'm still waiting on Bill Roberts' version, naturally. To me it seemed not like 'this is the intent' but 'this mix was crammed onto a poor quality tape, too hot by mistake, and then the azimuth on playback was completely off' (Bill, did you run the tape or were you presented with this as a digitized version?)

I dunno, Allen, I thought yours seemed mighty mono compatible too, but I admit I didn't actually check any of this with my mono switch- just did what seemed right.

Lee- alright, someone else who thought it seemed rolled! I R TEH vindicated Wink

The reason mine has that much treble boost but doesn't seem comb-filtered (_as_ combfiltered?) is, I had some very serious phase shift dialed in at the frequency where the treble was. It shifted forwards a bit going into the upper midrange and again, forwards quite a lot, way up top where there almost isn't any content. Understandably I'm very interested in whether people are liking that- it's unorthodox although you get an uncontrolled version of it with 'colored' analog EQs. This is strictly in the box though. Again, this is EQ with intentional phase shift pushing bass 'back' and treble 'forward' in time.

The alterations in mix character are mostly differences in EQ on side vs. mid, and a variety of different slight expansions, including the dreaded 'remap' (dreaded, because on a lot of content I can't touch it because it makes things crunchy). I'm also interested in whether it got crunchy on me too much. What happens is the voice 'stands out' too much and projects in a peculiar way in the midrange. That's what's separating the vocal from the background, which was almost impossible, let me tell you Very Happy

Title: Re: A cool exersize of skills and opinions.
Post by: Allen Corneau on April 28, 2005, 02:54:37 PM
Yeah, looking back I guess I approached this project as a "restoration", and to me that means do the best you can, but not at the price of something being changed for the worse.

Perhaps that's been a running theme through my mastering work as well, although I'm trying to break out of that. Confused

Allen
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 28, 2005, 04:05:23 PM
Hey, it's a valid approach- your take on it did not sound anything like bad. I'm only saying that at least for me and Lee, what we got seemed like 'the worse' already, and screamed 'change me radically'. I didn't percieve that as mix decisions, it sounded to me like a relatively normal mix that had been dubbed onto cassettes 1000 times with the azimuth off. I understand that this changed it a lot, and if it was meant to sound like that, woopsy  Twisted Evil

I'm all the more interested to see what Bill does, now. Does he go minimalist and treat the presentation as a set of mix choices, or does he do what me and Lee did, decide that it's a drum machine, bass, DX7 or something and voice- that he knows what those sound like- and break out the chainsaws and oxyacetylene torches to render the thing in a wildly different way?

That's certainly what I was doing when I chose to EQ that radically (had to be 20 db of notch in a narrow spot in the midbass) and apply the expansion stuff. I was like 'this is a drum box, and a keyboard, and I know what this stuff sounds like' and I tried to dig that out from the mud of the source.

Makes me wonder what would happen if we got some other posters to try their hands on this. Would they try to smooth the grunge out of the existing presentation, or re-imagine it into something more characteristic of them? In particular I'm curious how it strikes Brad, because the way the mud is shoveled onto this, it's like the Anti-Brad, it really is. Not only is it massive mud and no definition, it's phasey as hell and just about the opposite of his sound in every way. What would he do? I could see his take being closer to Lee's than mine or yours (Lee got some good clarity there), but without anything comby about it- but some of that is in the recording itself and has to be removed. Hmmmm...

Bill? Same goes for you- are you preserving the presentation of this track like it was intentional, or are you treating it like it's covered with a ton of mud and making it strikingly different?
Title: Re: A cool exersize of skills and opinions.
Post by: Lee Tyler on April 28, 2005, 04:38:45 PM
chrisj wrote on Thu, 28 April 2005 16:05

Hey, it's a valid approach- your take on it did not sound anything like bad. I'm only saying that at least for me and Lee, what we got seemed like 'the worse' already, and screamed 'change me radically'. I didn't percieve that as mix decisions, it sounded to me like a relatively normal mix that had been dubbed onto cassettes 1000 times with the azimuth off. I understand that this changed it a lot, and if it was meant to sound like that, woopsy  Twisted Evil

I'm all the more interested to see what Bill does, now. Does he go minimalist and treat the presentation as a set of mix choices, or does he do what me and Lee did, decide that it's a drum machine, bass, DX7 or something and voice- that he knows what those sound like- and break out the chainsaws and oxyacetylene torches to render the thing in a wildly different way?

That's certainly what I was doing when I chose to EQ that radically (had to be 20 db of notch in a narrow spot in the midbass) and apply the expansion stuff. I was like 'this is a drum box, and a keyboard, and I know what this stuff sounds like' and I tried to dig that out from the mud of the source.

Makes me wonder what would happen if we got some other posters to try their hands on this. Would they try to smooth the grunge out of the existing presentation, or re-imagine it into something more characteristic of them? In particular I'm curious how it strikes Brad, because the way the mud is shoveled onto this, it's like the Anti-Brad, it really is. Not only is it massive mud and no definition, it's phasey as hell and just about the opposite of his sound in every way. What would he do? I could see his take being closer to Lee's than mine or yours (Lee got some good clarity there), but without anything comby about it- but some of that is in the recording itself and has to be removed. Hmmmm...

Bill? Same goes for you- are you preserving the presentation of this track like it was intentional, or are you treating it like it's covered with a ton of mud and making it strikingly different?



Hi Chris. You and all of the other dudes here have WAY more experience/equipment/audio savvy than I will probably ever have, so I want to ask you guys a question regarding "phase". I know what phase is and how it sounds, but with a simple, rudimentary audio-editing program like Adobe Audition, how would one adjust the phase on the bass alone? I would imagine I would have to make a copy of the original track, make a sub-track with a proper low-freq range, and adjust the alignment of the left and right tracks to "sit right"??? I have no idea, really. And in regards to what I personally did to try to improve this presentation? After like 20 "fixes", I am truely clueless!  Shocked It is like I went into the ocean to refresh myself, swam about somewhat aimlessly, and then came back to shore kinda refreshed. Confused  Rolling Eyes

Lee
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 28, 2005, 06:09:33 PM
I'm not sure how you'd do it in Adobe Audition. There are quite a few issues going on here that can be referred to as 'phase'.

The way I manipulated the highs changed phase relationships because I had stuff split into different frequency ranges and moved the highs forward in time relative to the mids. If you had a frequency that was covering both ranges, one band would have it oscillating normally but due to the shift in time domain the other band would have the frequency shifted forward in its oscillation- so when the one was crossing zero, the other might be peaking out. That would be 180 degrees of phase alteration.
(edit- no, 90 degrees, nimrod- 180 degrees would be negative to positive peak)

With regard to the bass, what Bill was talking about is that when one woofer is moving out, the other isn't necessarily matching it- they are sort of fighting each other. I don't know why he says it's 270 degrees wide- perhaps he's measuring somehow that the same bass guitar waveform is nearly a whole cycle delayed on one channel, but one cycle at what frequency?

I will say this- all this phasey stereo hoo-hah is making me want to set up my software with _stereo_ group delay hackery. I'm like, 'wait a minute, what if I did have the bass band come out with different adjustments for right and left?'. Sounds like a reasonable enough suggestion, and I'd like to be typing in the delays as numbers- I have 'em on a slider and it's a bit vague. If I did that, I could change the phaseyness significantly. Whether that is desirable is an entirely different question Smile
Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 28, 2005, 06:15:41 PM
Here is mine..for fairness, taken directly off the mp3 from this post.

I will explain; after everyone does a comparison.

I am not saying who is best here..it is for comparisons. You all decide.
Title: Re: A cool exersize of skills and opinions.
Post by: Cary Holding on April 28, 2005, 07:57:43 PM
I'll play along.
Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 28, 2005, 08:28:55 PM
Here they all are, in order, Starting with original, Allen, Chris, Lee, Myself, Cary
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 28, 2005, 09:24:36 PM
Right, comparisons 'r us. In the order given:
Original. Dead

Allen: better controlled, pretty dull like the original, Bassdrum sort of rumbles interestingly, I like that. Vocal sounds very similar to the original.

Chris: apparently I like drum machines, because I contrived to have it much more present. Vocal is way more spotlit, but without sibilance getting out of control. Sort of grainy, thanks to all the treble boost. Sounds a bit like it was re-recorded, so great is the alteration. I still like it Very Happy

Lee: hey, shaker! Voice is sort of weird as it's got roundness but a real tizzy edge. I like the bassdrum better than on mine- partly because I took away the reverb from behind it to make it more focussed. You can always have more bright than the next guy but it does tend to make things too upfront. I sympathise with this version completely. Brothers in bright Wink

Bill: I'm really liking the rimshot. I'm really liking the bassdrum. I don't think anyone got a version that's better behaved than this- but it freaks me out how distant it sounds. Is that really what this guy was trying to do? I know that my and Lee's version must be hurting you over the tweeters-center Yamaha uberspeakers, but what you're doing isn't translating to my rig, and my rig is not exactly treble-shy. That said- my version and yours are doing something similar with the bassdrum there. What are you doing to make that happen?

Cary: I like the overall frequency balance here- like Allen's version, this is making the sloppiness of the original recording behave, without doing anything radical to the sound.

Very interesting. I guess my question now is: what did you mean by bass phase, Bill, and whatcha do? I know I mid/side EQed really radically, and then got medieval with group delay, roughly like this:
0-300hz, delayed very slightly
300-1K or so, forward a bit
1K-10K, baseline
10K+, forward even more

Since you got similar behavior off the bassdrum and all, how'd you adjust these things? Your methods would probably translate better for other people since I hadda write software to do it. I'd say whatever it was, it's worth doing.
Title: Re: A cool exersize of skills and opinions.
Post by: Lee Tyler on April 28, 2005, 10:31:32 PM
I must admit there is a honky thang' going on vocal-wise in my attempt that "forced" me to drop a few db centered around 283hz with a Q of 3. Now I can live with myself. I will leave the old version there for now.  Rolling Eyes  

Lee
Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 28, 2005, 10:32:59 PM
Being very busy..and not reading your last post Chris, think DVD soundtrack response. I am at liberty (due to content) to post a modern set of snips of a modern soundtrack balance.

(Editing of a movie I worked on)

More later...I am in heavy editing now..taking 5 to catch the thread...but I am on an 18 hour day..so I got to keep commitments..and will travel back here when I can..

PS..Chris, this was cut from a CD of the original tape. For all that participated to date, I will provide whole song so you see where it goes..

Sorry so tied up.
Title: Re: A cool exersize of skills and opinions.
Post by: HansP on April 28, 2005, 10:44:38 PM
here we are
I like the results of crh and ajc.

I did not phase shift the lower mid+high bass to get the upright bass sound ok, this was done by the others quite well. but it is working with mono switch, sounds much clearer than the original, and distortion is tamed in spite of the brightness enhancement.

ah FYI- in the source, the left channel is ~3 samples late..
and I think we are beating a dead horse here but its fascinating to learn and practise.
an AI algorithm could do some more about the distortion, it needs to model the dolby behavior to get down to a reliable transfer curve (histogram inversion etc).
Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 29, 2005, 12:41:51 AM
Sound sweet hans...remember, movie context...level lower will give a different frequency layout..on your buss..


Study movie soundtrack level, not pop music nor cd.

See if that affords you more depth.

back to work here.../w me
Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 29, 2005, 12:48:10 AM
Movie level, this is hot for it.

Notice eq curve, clean and not brassy, round.
Title: Re: A cool exersize of skills and opinions.
Post by: Ronny on April 29, 2005, 01:36:19 AM

Not sure what you guys are trying to do here, I didn't know it was mastering for film when I read the posts a half hour ago. Anyway here's another version.

Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 29, 2005, 10:12:07 AM
Level lower will give you a different frequency response on your buss?

I don't get it. Unless you're trying to produce a backdrop/bed to go behind dialogue (a perfectly legitimate thing to do), I'm not aware that film work requires levels to be real low or the top to be so rolled off. I thought current films were experiencing just the same problems of hyperlimiting that pop music was.

If somebody had said 'this has to go behind dialogue, Chris' I'd have been like 'oh!' and set it up more in the far field. That's not difficult, it's just the last thing I'd expect to do for a pop release- or the focal point of a DVD soundtrack. I admit to being very confused by this, and by the idea that lower level gives you a different frequency response.

So you want it quieter than the original source, and set up in the far distance? Okey dokey. Give me a few minutes.

Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 29, 2005, 10:30:08 AM
Actually, this exersize is more of "what would you do with this old track" whether for a movie or not. The track has been used in an upcoming movie (very difficult unless mono to feed in properly) and everyone...has a different take on it. So far, Ronny seems to have the cleanest restoration of it. Restoring first before folding into a soundtrack is very important...certainly.

Ronny did really well at cleaning it up.

Objective here..is:

Without knowing the use, what would you do? ..and it has proved very interesting, no doubt. Allen did not change the balance at all...and made the track sound really nice. All I did was to mono the bottom (everything below 400 6dB/octave) and not much else...because..changing the overall "selected" piece is something that the producer may not want. Should this represent the sound of its era or sound up to date? How deep do we go to find out what the intended purpose of the track is? Restoration, for CD, Film, Advertisement? Do we take the time to find out where it will ultimately end up? How important is it to know?

I also notice how folks are listening to others to get a reference and this could be good..or maybe not good. The reference is the original. Again, Ronny ..so far has the best averaging of all the factors.



So basically, everyones take is interesting, no doubt.

Knowing how the track is to be applied is part of the communication but everyone has a preference.

Chris, analog busses behave differenly at different levels and digital is also reported to change dynamics and frequency curve..depending on how hard it is pushed..but it is subjective and I have not seen any scientific data to really support that claim. We know...compression changes the FR curve.
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 29, 2005, 10:47:09 AM
*LOL*

So the idea is, here, master this track, and then we'll see if you decided not to master it? And all you did was sum the bass? That's not true- the whole reverberant field collapsed somewhat on your take, which I thought was an intentional effort to control the washiness. You didn't mean for that to happen? Must have been the two layers of mp3ing.

The wav example you've put up isn't what I think of as 'film score' quality- it is an unrestored historical recording. Is the idea to make the new track (with drum machines and all) merge seamlessly with the historical recording, or is that just an example of something else you've done for DVD?

Give me a few minutes, I'll put up a track that's at the same general level and balance as yours (but is still 'fixed up'). Who knew?

Ronny's take is one of the most radical changes when you go to mono. I thought the idea was to push for more mono compatibility? Not that you said that, specifically  Confused
Title: Re: A cool exersize of skills and opinions.
Post by: OTR-jkl on April 29, 2005, 10:47:13 AM
Well, I know zero about movie soundtracks, but I gave it a shot. Didn't even try to restore it, I just tried to make it sound as nice and smooth as I could...

(Hope this attachment thing works...)
Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 29, 2005, 10:52:06 AM
That sounds wonderful OTR! you still have the spread in there but it does not take away from the vox.

This is all so "matter of opinion" on the excersize...and everyones count.

As the title says, Skills and opinions. Had I posted "for a film" would it have been done differently?? and why?

We know..DVD's are many db less than popular CD's..to the point of..if you are watching a dvd on your workstation, you better lower the level by an extreme amount before going to cd.

The key here...are we learning anything? I certainly am..and I like it too!
Title: Re: A cool exersize of skills and opinions.
Post by: HansP on April 29, 2005, 11:20:20 AM
Level wrote on Fri, 29 April 2005 06:41

Sound sweet hans...remember, movie context...level lower will give a different frequency layout..on your buss..

Study movie soundtrack level, not pop music nor cd.

See if that affords you more depth.



thx!
so how is this one? Wink
added some expansion and stepped back a bit, from the HF boost.
(changed C -> D went to a more vintage approach, the other was somewhat synthetic)

with ronny's take, I have the problem of denoizer artifacts.
to cure the tape hiss, I would need a noise footprint.
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 29, 2005, 12:14:42 PM
OK, here ya go with the far-field one (would have done it quicker but I did have to do the whole thing from scratch, and I was grabbing a shower and some breakfast while I was at it)

That more like what you wanted?
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 29, 2005, 12:20:50 PM
Hmm, turned it around in about an hour and twenty minutes- I have GOT to get my software running in OSX, if I wasn't rebooting the damn computer and taking showers and drinking chai tea (MMMMM, chai tea) I could have turned this around in a half hour.

I always figure, sometimes being able to work quick is useful. I suspect it's extra useful for me, because I can make the sound do... a lot of things, but WHICH things I choose to make it do, sometimes that's cause for 'iteration'. I'm trying to keep iteration to a minimum anymore- I think people tend to tune out after a couple tries. In this case I can justify it on the grounds of "you wanted it to do WHAT?" Very Happy

Yay, clients Dead  Very Happy
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 29, 2005, 12:39:09 PM
Oh yeah, and-

HansP wrote on Thu, 28 April 2005 22:44

an AI algorithm could do some more about the distortion, it needs to model the dolby behavior to get down to a reliable transfer curve (histogram inversion etc).


Actually, I'm doing a version of that, Hans: at least I'm essentially making a histogram and keying off that for the expansion. The first try, I was remapping sample values to adjusted values (which can get very aggressive sounding), and the second time I didn't, because it tends to eat the reverberant field and peel sounds off it, moving them forward.

and-

Bill, a digital buss does not have its frequency response alter at different levels (that's part of the reason they don't sound as nice!) Neither does compression. Now, in each case there's a 'gotcha', as follows:

On a digital buss, if you're trying to reproduce seriously high frequencies, it'll take some headroom to do them properly. The reconstructed waveform can overshoot where the samples are. So, if you push digital past a certain point the highs start to shut down and to sound glarey.

With compression, if the release time is too fast it'll start to affect the bass. If you had compression with a super slow release time you'd get no alteration in frequency response, but as it speeds up it'll start to interact with the bass tonality. And since limiting is infinite-slope super-fast-release compression...

Apart from these reasons, gain changes in digital do not affect the frequency domain. (if I'm missing a phenomenon here, I'd be delighted to hear about it- I think I covered everything that can possibly happen)

Title: Re: A cool exersize of skills and opinions.
Post by: dcollins on April 29, 2005, 12:52:24 PM
Level wrote on Fri, 29 April 2005 07:30


Chris, analog busses behave differenly at different levels and digital is also reported to change dynamics and frequency curve..depending on how hard it is pushed..but it is subjective and I have not seen any scientific data to really support that claim.

That's because, below clipping, none of this is true!

Quote:


We know...compression changes the FR curve.



"We?"

Bill, tell us more about when you cut lacquers in the 1970's on klipsch speakers?  People love to hear about how they did it in the old days.  Did you really have to keep the levels down do avoid vibrating the lathe?

DC

Title: Re: A cool exersize of skills and opinions.
Post by: Level on April 29, 2005, 12:55:37 PM
Sigh...... Rolling Eyes
Title: Re: A cool exersize of skills and opinions.
Post by: PP on April 29, 2005, 01:09:30 PM
Title: Re: A cool exersize of skills and opinions.
Post by: HansP on April 29, 2005, 01:24:31 PM
chris,
you need to measure or guess a reference histogram, and also take into account that the problem here may have another origin in tape hysteresis with a bad HF bias circuit. then a mismatched dolby decoder plus a worn-out tape, and the chaos is complete.
so there must be kind of dynamic discriminator, using parts of these mp3 algos, that judge the relevance of harmonic content.
then implement a multidimensional feedback loop, that controls the transfer curve. the dimensions would be, what you get from modeling (process identification) relevant aspects of known behavior of defective tape machines. then minimize irrelevant HF content.   Twisted Evil
and that would still miss the intermodulation part...

I watched the histogram and by instinct and experience decided for a certain transfer curve.  Razz not very serious but hey, listen...
(and then I was bitchy enough to train the denoiser on an excerpt of the worst moments, where distortion still was annoying)
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 29, 2005, 01:35:04 PM
I have listened, and I like it, Hans. You've definitely corrected for the transfer function weirdness, I do indeed hear it. I find that bumps in the histogram translate to a sort of hardness/fatigue. Your correcting it clears up that tacky DX7 sound, which otherwise gets stuck to the bass at times.

I do measure- my software loses a bit of time as it has to prescan the entire song and build a histogram (if I have those features switched on, that is).

What I do from there is just decide it's meant to be smoother, and use that assumption to control the expansion or compression. I'm pretty happy with it (wish I'd done the distant-tone version earlier, everybody's getting bored of listening to this song by now. Ah me)

Now you're making me want to code a dynamic discriminator and multidimensional chaotic discombobulator. No, wait, that would be the original track Wink
Title: Re: A cool exersize of skills and opinions.
Post by: turtletone on April 29, 2005, 03:45:43 PM
Poyser wrote on Fri, 29 April 2005 13:09

Sigh.... As Well... Rolling Eyes Razz  



Oh my gosh, this must be the shortest post you've ever written. Shocked
Title: Re: A cool exersize of skills and opinions.
Post by: PP on April 29, 2005, 03:58:01 PM
Title: Re: A cool exersize of skills and opinions.
Post by: turtletone on April 29, 2005, 04:12:24 PM
I specialize in restoring old recordings of turtle's singing. Some of the earliest ones are from the 50's. I can also break a board with my earlobe but I don't do that for a living.
Title: Re: A cool exersize of skills and opinions.
Post by: dcollins on April 29, 2005, 04:58:19 PM
Level wrote on Fri, 29 April 2005 09:55

Sigh...... Rolling Eyes



Bill, call me crazy, but I'm beginning to think you sometimes just make stuff up, because you will never answer any follow-up questions about claims you make!

DC
Title: Re: A cool exersize of skills and opinions.
Post by: PP on April 29, 2005, 05:19:25 PM
Title: Re: A cool exersize of skills and opinions.
Post by: PP on April 29, 2005, 05:23:36 PM
Title: Re: A cool exersize of skills and opinions.
Post by: bblackwood on April 29, 2005, 05:27:49 PM
Poyser wrote on Fri, 29 April 2005 16:23

Q DC: "you will never answer any follow-up questions"

Actually this is a brilliant method of operation, because you can make your point, but never have to be answerable to anyone.

Actually, anyone who claims anything here should be prepared to answer any questioning that comes from their claims, be it Bill, DC, me - anybody.

If one doesn't want to offer proof of one's claims, there are many other boards where one can post them.
Title: Re: A cool exersize of skills and opinions.
Post by: dcollins on April 29, 2005, 05:50:11 PM
Poyser wrote on Fri, 29 April 2005 14:23


Actually this is a brilliant method of operation, because you can make your point, but never have to be answerable to anyone.



Or a way to just make outrageous claims of things you've done, gear you have, records you've done, and not be accountable?

Quote:


What if they tested Bill's I.Q. and found it's twice both of ours put together Dave?



I'ts my understanding that it was originally called the Stanford/Roberts test, before Benet got involved.


Quote:


Perhaps this is the reason you 'struggle' with Bill's 'ground breaking' methods so?



Perhaps.  Or perhaps my BS meter is more sensitive than yours?

DC

Title: Re: A cool exersize of skills and opinions.
Post by: PP on April 29, 2005, 05:51:12 PM
Title: Re: A cool exersize of skills and opinions.
Post by: Ronny on April 29, 2005, 06:12:47 PM
HansP wrote on Fri, 29 April 2005 11:20

Level wrote on Fri, 29 April 2005 06:41

Sound sweet hans...remember, movie context...level lower will give a different frequency layout..on your buss..

Study movie soundtrack level, not pop music nor cd.

See if that affords you more depth.



thx!
so how is this one? Wink
added some expansion and stepped back a bit, from the HF boost.
(changed C -> D went to a more vintage approach, the other was somewhat synthetic)

with ronny's take, I have the problem of denoizer artifacts.
to cure the tape hiss, I would need a noise footprint.




Ideally we would have all had a higher res aiff or wav copy and some dead air to noise profile for the fingerprint. The fact that the clip starts at high level taken from the middle of the tune and a fade to black done digitally at the end pretty much negates noise profiling, but alas if you want to make a living in this business, these are things that you have to learn to deal with. We can't always get the sections of tape that we need, to do the most efficient restoration job and this clip falls under that category. After all folks we are attempting to master an mp3, it's not a Steinway and I agree with Bill that mp3's get a bad rep, because an mp3 is only as good as the source material and the person that created it. In proper hands mp3 is a viable medium for playback, but it certainly doesn't take well to the same processes that you can use on .wav's and aif's.

Chris, if you'll A/B mine with the original, you just may find that the instruments are heard more cleanly and appear to occupy better spaces, but without altering too much from the original mix. Pan trajectories are not altered and I used no M-S. As far as mixing for mono and worrying about mono compatibility, I no longer worry about it, because I don't feel that compromising the stereo mix to make it more mono compatible is warranted these days. How many mono listening stations is the song going to go through? A mono cheapo clock radio that wakes you up with WKRP, a few AM stations that mainly feature talk shows. 99.9% of the listeners today, listen through stereo systems on this type of genre. I mastered the tune not with film in mind, but just did what I normally do, which is what I thought you guys were doing, until I read the posts after I mastered my version. Anyway Bill cleared that up.

Let me give you my take on the rest of the versions, the originals that were on or before the "all clip". The most offensive thing that I heard on the original song, was the non-audio noise and that's what I felt addressing would do the most for this song. On all but Bill's and Allen's versions, on my system the noise has actually increased. No doubt due to some of the folks boosting the hi-mids to bring out the hat. While the hat sounds more profound and crisper, the freq's that were altered to achieve this accenuated the noise above the level that it was at in the original, no surprise as the hat and hiss occupy the same freqs. Mastering to me is all about give and take, you can never have a perfect song and you have to weight what is beneficial to the overall composition. If it means not having the hat seated where you want and keeping the noise floor down, than it's a good trade off and the song will sound better in the end. Although Allen's and Bill's version weren't as clean as I would have liked to have heard them, they didn't increase the noise.

WRT, the low end, there is some bass resonance on the original, worse at some spots than others. I heard one version that increased the bass rumble on my system and spread it to more notes across the timeline, it sounded worse than the original. The bass notes weren't great on the original and when you are dealing with low end on the 2 bus, it's not an easy task to give space to the bass notes on some tunes that have the lack of recording quality or lack of archive longevity of this tune or the mp3 medium as the only source, but there are some things that you can do to attenuate the resonance so that the notes don't sound like they are run together in just one ball of low end. Again this is a trade off situation of having just enough low end or trying for more and boosting the wrong freq's where the resonance is most profound. Typically when I master stuff from the home recording crowd it's sometimes too bright or too boomy and I think this has to deal with room acoustics and quality of monitors. We all hear differently and we all have different systems, what I'm listening for in a tune is going to differ from the next guy, but I've found that there is a medium ground when it comes to restoration and mastering, often more is less and less is more and part of the key is knowing what not to do and not so much in what to do.    
Title: Re: A cool exersize of skills and opinions.
Post by: PP on April 29, 2005, 06:14:40 PM
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 29, 2005, 07:33:29 PM
Well, I'd love to answer questions, but it seems like (1) I'm already answering them so nobody needs to bother asking, (2) I'm talking arcane tech-gibberish but it happens not to be BS, just sort of fringe, and (3) as soon as I come up with something that's actually good by the unwritten rules, it goes uncommented because Bill isn't actually setting out to lose or anything  Confused

I think I nailed it the second time around. For the first time, I would've needed a noisefloor sample, and better yet an AIFF or WAV. You cannot boost the highs that much off a totally murky mp3 at any bit rate. It's still like a sixteenth of the information of the uncompressed version, and the low level stuff is exactly what goes. So I boosted them anyway, sue me Wink

It's all good practice and a chance to get feedback and critique- I hope there are still people game to critique the entries including those done after Bill explained what we were supposed to be doing in the first place. Color me a noisy rock freak. I thought it wanted to sound 80s, what with the synths and all Wink
Title: Re: A cool exersize of skills and opinions.
Post by: HansP on April 29, 2005, 07:37:42 PM
hmm, bill gave us a zen koan to play with..

ronny, kudos, and good to discuss.
without instructions, much is up to taste.

* ok, I should bring my tape hiss library from the basement  Razz
the tradeoff is obvious, we can have it clean, with a good hihat, and no artifacts - any two of them!
I chose for more openness and a nice hihat. personally, I don't mind a little hiss in old recordings, I prefer to get the maximum of the information that has survived. to me, most denoisers sound very ugly or make it dull when they are adjusted for a bigger impact. also in a non-audiophile surrounding, the noise wouldn't big time disturb, it's mostly on the high end.
still it is true, that another pass with a well-chosen tape noise model would improve the thing remarkably.

* I'd like to remind that nowadays a big number of listening systems have a single bass woofer.
bill and I have tried very similar: we collapsed the stereo width for the bass. so this is what we get. the nice harmonics that make the bass clear and precise, are anti-phase, and the resonance is mostly straight. so some results are very good, where the contributors have time/phase-shifted parts of the bass spectrum. this time, I left that out, - will need to find me a generic allpass to check around. I think, here it is better than time-shifting the LF.
lee: I like the bass drum! in my perception the low end is somewhat too much, but with a good structure, so it is easy to attenuate.

btw, reminds me of a theater hall, where a friend of mine was the audio operator, and the famous sound company had installed the speaker cabinets with a mis-connected bass woofer on one side.
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on April 29, 2005, 08:42:03 PM
HansP wrote on Fri, 29 April 2005 19:37


I chose for more openness and a nice hihat. personally, I don't mind a little hiss in old recordings, I prefer to get the maximum of the information that has survived. to me, most denoisers sound very ugly or make it dull when they are adjusted for a bigger impact.


Indeed, that's very much how I see it. If I'd had a sample of noisefloor I'd have tried to do noise reduction- maybe not, mp3 will totally screw that up by 'gating' most bins anyway- but I'd have only ducked the gated bins a little, not cut them out entirely. It's like some other types of correction I've seen, where you don't obliterate the bad quality completely, you just tone it down until other things distract the attention from it.

Quote:


bill and I have tried very similar: we collapsed the stereo width for the bass. so this is what we get. the nice harmonics that make the bass clear and precise, are anti-phase, and the resonance is mostly straight. so some results are very good, where the contributors have time/phase-shifted parts of the bass spectrum.


Both times I tried it, I treated it as a matter of EQing mid and side separately. In the case of the side channel, it wasn't about obliterating all bass, just dialing it back until it didn't have that overloaded, resonant quality. I actually had it continually diminishing to something like 30 db down by the time you got to 10 hz, as if I was contriving to cut lacquer. The mid channel proved bass-shy when you took the side out, so I boosted. The combination of these effects meant that the bass guitar was more controlled but still had some of the original character- bass drum did end up considerably louder than the source, but I was trying to balance it with the bass guitar and had reasonably okay results doing that. The expansion helped- I can set it to track the lowest frequencies and expand them, and that helped define the bass drum lows.

So the mid/side stuff is partly like collapsing the stereo width for the bass, except that you can also do the inverse EQ on the mid channel and not change the overall balance that much. I do like the idea of taking bass out of Side content- the deal is, if you're low enough that the wavelength is close to the distance the woofers are apart, out-of-phase bass is totally wasted and does nothing. One pushes, the other pulls, the pressure zone in the room remains the same and you're just burning amplifier power to no effect.

If I was doing a third try I'd shift phase differently for each channel to see if I could make the bass guitar more interesting- but I ain't doing a third try Very Happy that sort of thing gets boring, I'll live and die by what I already did.
Title: Re: A cool exersize of skills and opinions.
Post by: dcollins on April 29, 2005, 10:25:51 PM
Poyser wrote on Fri, 29 April 2005 15:14


Yes OK, I know what you both are saying, and I fully accept Brads rules.


As do I.  Brad has only deleted one of my posts, although it was a hilarious one!
Quote:


I just like to point out that Bill’s worth his weight in gold.


Agreed.

Quote:


(Actually I am hoping against hope that eventually given enough time, this dear gentleman, will come up with the goods).



I would honestly like to know more about things that Bill discusses, but when pressed nothing ever seems to come of it....

Quote:


I know where they are, but you don’t expect me to find them for him do you?




Have you seen David Griesingers stuff wrt low frequency "envelopment?"

DC
Title: Re: A cool exersize of skills and opinions.
Post by: PP on April 30, 2005, 04:20:50 AM
Title: Re: A cool exersize of skills and opinions.
Post by: HansP on April 30, 2005, 09:06:07 AM
so it is all about theater (and meta-theater.. umm...) Rolling Eyes
Title: Re: A cool exersize of skills and opinions.
Post by: PP on April 30, 2005, 09:12:31 AM
Title: Re: A cool exersize of skills and opinions.
Post by: dcollins on April 30, 2005, 10:52:59 PM
Poyser wrote on Sat, 30 April 2005 01:20

David, I’m not aware of, and I haven’t seen anything new from David recently David, just stuff David wrote from a few years ago David.



Whew, we need to turn the echo-canceller on for those long distance calls.

Quote:


All frequencies have a role to play and are actually contributory to what is perceivable by the listener as ‘enveloping’. NOT just Bass sub frequencies.



Sure, but I think DG's point also had to do with the "transverse" wave and its supposed contribution.  In the concert hall.

Quote:


I actually would LOVE David to come in on this David. I kinda think he would tend to side with my views David.



I've never seen him in the forums, probably too busy.  I remember when Eric Benjamin of Dolby discussed j*tter on the Sursound list.  Or what happened to Erik from BF; guys who actually knew something............

Quote:


And if you were to accompany me to certain big stores I could show you stacks of returned (name brand) systems just laying around, gathering dust where people have returned them, completely dissapointed in their actual realism of performance.



Hoping to visit ol Blighty in Sept. and would love to take you up on your offer.

DC
Title: Re: A cool exersize of skills and opinions.
Post by: matucha on May 01, 2005, 05:06:15 AM
I lost kik, the body of it... no time to get it in again... Good news is I'm almost 100% mono compatible Wink.

Title: Re: A cool exersize of skills and opinions.
Post by: PP on May 01, 2005, 06:15:53 AM
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on May 01, 2005, 10:19:30 AM
Well heck, any of you guys coming to New England in the fall, should come to southern Vermont and stop in for a visit. Bring cameras and time it for leaf-peeping season Smile
Title: Re: A cool exersize of skills and opinions.
Post by: Lee Tyler on May 01, 2005, 02:29:54 PM
chrisj wrote on Sun, 01 May 2005 10:19

Well heck, any of you guys coming to New England in the fall, should come to southern Vermont and stop in for a visit. Bring cameras and time it for leaf-peeping season Smile



Used to go to Brattleboro every year to get the hell out of NYC in the summers. Where are you up there??  Liked to take trips up to Hickin's Mountain Mowing farm and get those giant strawberries that were sweet as sugar. Best on the planet bar none! Also that cool swim-hole at the Dummerston Bridge. Gotta get my ass back up there. You live in a beautiful slice of this country, Chris!

Lee
Title: Re: A cool exersize of skills and opinions.
Post by: chrisj on May 01, 2005, 02:59:21 PM
Bellows Falls- out past Putney. If you're on 91 it'd go Brattleboro-Putney/Dummerston-BF.

If you're in the area, drop me a line and stop by!  Smile
Title: Re: A cool exersize of skills and opinions.
Post by: schley-may on May 01, 2005, 03:00:53 PM
If anyone is still interested in the original intent of this thread, I've take a slightly different approach than I've seen discussed so far.

analysis
Using a 200Hz and 4KHz multiband split:
Bass band has phase flipped on one channel, so does high band. You can see this from watching the band selected correlation meter.
Mid band freqs were set around vocals (and synths). Vocals are phase correct, some of the synths are flipped.

strategy used
Split into separate tracks for each band.
Flip polarity on bass R channel, narrow about half way to mono (using M/S).
Leave phase alone on mid channel. This leaves vocals mono compatible, but some of the synths receed in mono. Better than the other way around. Bring left channel toward center a bit to even spread.
Flip polarity on high band R channel. Use a little exciter on high band to brighten and (I think) mask some of the splatter.
Mix three channels to taste.
Final eq and about 2.5dB compression/boost.
All eqs and band splits linear phase.

Comments?




Title: Re: A cool exersize of skills and opinions.
Post by: Lee Tyler on May 01, 2005, 03:18:14 PM
schley-may wrote on Sun, 01 May 2005 15:00

If anyone is still interested in the original intent of this thread, I've take a slightly different approach than I've seen discussed so far.

analysis
Using a 200Hz and 4KHz multiband split:
Bass band has phase flipped on one channel, so does high band. You can see this from watching the band selected correlation meter.
Mid band freqs were set around vocals (and synths). Vocals are phase correct, some of the synths are flipped.

strategy used
Split into separate tracks for each band.
Flip polarity on bass R channel, narrow about half way to mono (using M/S).
Leave phase alone on mid channel. This leaves vocals mono compatible, but some of the synths receed in mono. Better than the other way around. Bring left channel toward center a bit to even spread.
Flip polarity on high band R channel. Use a little exciter on high band to brighten and (I think) mask some of the splatter.
Mix three channels to taste.
Final eq and about 2.5dB compression/boost.
All eqs and band splits linear phase.

Comments?

Hey Jim, I am very much still interested in how one approaches tailoring this "maladjusted suit" to sound/fit it's best. I like what you have done here, and I appreciate you demonstrating some of your techniques as well. Cool approach.

Lee







Hey Jim, I am very much still interested in how one approaches tailoring this "maladjusted suit" to sound/fit it's best. I like what you have done here, and I appreciate you demonstrating some of your techniques as well. Cool approach.

Lee
Title: Re: A cool exersize of skills and opinions.
Post by: Lee Tyler on May 01, 2005, 03:37:25 PM
chrisj wrote on Sun, 01 May 2005 14:59

Bellows Falls- out past Putney. If you're on 91 it'd go Brattleboro-Putney/Dummerston-BF.

If you're in the area, drop me a line and stop by!  Smile


Big 10-4 there, Chris. Thanks!


Lee
Title: Re: A cool exersize of skills and opinions.
Post by: matucha on May 02, 2005, 02:08:33 AM
Jim Schley-May > analysis and technique... almost the same as I used, maybe that's the only way Wink, however I split it only in 2 bands.

You raised the voc, that's nice, but I don't like the tradeoff - drums. And... you've lost the (low of the) kick too.

However your ex. doesn't suffer any big phase cancelations in mono as the rest of the examples posted here.



Other listenable examples IMO:
CJStayFarField (collapses in mono)
AJC Stay 01 (collapses in mono)
Stay OTR (collapses in mono)
BR Stay (bass ok in mono, but the rest becomes muddy in mono)
Title: Re: A cool exersize of skills and opinions.
Post by: invisibl on May 03, 2005, 03:25:53 AM
Gee how I'd like to hear DC Brad et al have a go at this..


Title: Re: A cool exersize of skills and opinions.
Post by: matucha on May 03, 2005, 06:42:57 AM
me too... because I'm no pro mastering engineer...