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Low volume sample rate and quantization

Having more a higher sample-rate with lower volume helps with digitization.
  [vote for,

The problem with digital recordings is, that when the analog sound is too low, it will be cut out during quantization. If the recording system gives unevenly a higher sample rate to a lower analog sound, it can be used to amplify low voices without clipping.
Thrust, Jan 24 2019

My first "drum sequencer". https://goo.gl/images/QDZfFY
[doctorremulac3, Jan 26 2019]

Why John Bonham is better than a drum machine. https://www.youtube...watch?v=UvOm2oZRQIk
There's a couple of reasons. [doctorremulac3, Jan 27 2019]

Yea, you could program a machine to do this... https://www.youtube...watch?v=_4BhsYbXwf4
... but it woudln't be particulary linteresting. Humans performing are more interesting than machines doing what they're told to do. [doctorremulac3, Jan 28 2019]

My key to the music biz. https://en.wikipedi...File:E-mu_SP-12.png
More like the shaped charge I strapped to that seemingly impenetrable foot thick steel door between a young man of limited financial means and the music business. [doctorremulac3, Jan 28 2019]

Lots of floating point ADC stuff https://www.google....o+digital+converter
// Another might be to make a direct floating point analog to digital converter, which I've never heard of being done. // [notexactly, Jan 29 2019]

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       But if all of those higher-rate samples are below the threshold, won't you still clip?   

       There is one way to modify digital sampling so that gives it almost the same dynamic range as analog, even down to signals well below 1-bit strength. What you need to do is to add random noise to the signal, equivalent to about 1/2 of one bit on average. Then your less-than-1-bit signal adds statistically to the noise, with the result that it's represented more or less proportionately.   

       The downside of this is that you then have noise on your recording. However, for very weak periodic signals (like singing, or vowels), the brain is good at picking them out from the noise, and it all works out OK.
MaxwellBuchanan, Jan 24 2019

       [+] but I'm not sure I completely grok it.
FlyingToaster, Jan 24 2019

       I'm a be confused, what's the difference between analog sound being too low and "cutting out" and a digital snapshot of that part of the wave not having enough information to put into a digital format?   

       Wouldn't you just put a compressor on the signal, an automatically acting "robot arm on the volume" to achieve what you want?   

       Seems like a higher sample rate of something too low to hear would just create a clearer, more perfect representation of something too low to hear.   

       The idea of a continuously variable dynamic sampling rate is intriguing though. [+]
doctorremulac3, Jan 24 2019

       //Wouldn't you just put a compressor on the signal// Yes, possibly.   

       //more perfect representation of something too low to hear// That's what I thought.   

       Adding low-level noise in order to bring weak signals above threshold is fairly well-established as a method. In fact, the human visual system probably does it, to improve night-time sensitivity.
MaxwellBuchanan, Jan 24 2019

       I do not mean bass with a low voice, but more like silent. Let's say that we record a cymbal. First it sounds to resonate nicely. When the sound comes more silent, the high part of the vibration can be heard, but the low vibration is chopped off because it is below the quantization limit. After that there is no sound at all, even if the cymbal is still ringing. If there would be a higher sample rate for more silent sound, it would not lose the information that is in analog sound.
Thrust, Jan 24 2019

       The higher sample rate won't achieve anything - you're just taking more samples-per-second of a sound that's too weak to register. You may be confusing amplitude and frequency. The cymbal maintains roughly the same frequency (or, rather, a complex mix of frequencies) as it decays, but their amplitudes decrease.
MaxwellBuchanan, Jan 24 2019

       Yea, I think you're over complicating digitization. It's just a lot of little snapshots of information about something that's already perceivable so it can be re-created.   

       And "snapshots" isn't really accurate either. Lot of info in a snapshot, digitization only has two kinds of information, on or off, but there's a shit ton of this on or off info that represents what you've recorded.
doctorremulac3, Jan 24 2019

       ...sorry, "metric" shit ton.   

       Lots of Europeans on this site. Need to speak the lingo.   

       But again, the idea of a dynamic, continuously variable sampling rate is kind of interesting. Thought you needed 32 bits for that sound? Maybe that vowel sounds fine with 8 bits. Then kick in the higher rate for sounds that need it.   

       Is that a need for that? This is the Halfbakery. We don't do "needed" here.
doctorremulac3, Jan 24 2019

       //Lots of Europeans on this site. Need to speak the lingo.// No no, it's fine, really. Most of us in England still remember the old system (or Imperial, as it's known), and it's only a problem at the interface between the US and the rest of the planet. Good to know it's still working for you. And on the plus side, trade between the US and Myanmar is much easier that way.   

       Now, where'd I leave that 17/43rds spanner...damn, maybe I left it out in the 91.44cm.
MaxwellBuchanan, Jan 24 2019

       I read recently about this, how one bit can be used to switch to a different ceiling. So quiet passages have the extra bit "on" to indicate that they are sampled at a higher amplification. When the signal becomes stronger, the extra bit is switched "off" giving half the resolution but double the headroom. I think this was many decades ago, before audiophiles realised that the signal had a digital stage. Perhaps to do with FM radio? Can't remember.
pocmloc, Jan 25 2019

       //higher sample rate won't achieve anything - you're just taking more samples-per-second of a sound that's too weak to register//   

       True, If you can't hear it in analog you won't hear it in digital.   

       Analog is all information. Digital is on/off informational parts. Theoretically there are more sounds in analog than digital. A higher rate is always going to be more information which the brain can possibly interpolate more sounds.   

       Maybe there is a prime imperial function of sampling that helps specific sounds with loss of others.
wjt, Jan 25 2019

       Finally we're getting into a subject I actually know a little about. I used to be in the music biz in my youth at the time of transition between analog and digital. I've mentioned that I never got a college or even high school diploma but I do have a wall full of gold and platinum albums so I could probably get a job teaching something music related in college, like "How to get a wall full of gold and platinum albums 1.01". (Lesson 1 would be "Give it up, it ain't gonna happen.")   

       Anyway, digital recording on the production side got a bad rap when it first came out as sounding "harsh" because people didn't know how to use it. It recorded the object making the noise very clearly, whereas tape would soften, crush and smash everything in a very pleasing way. It's been called tape compression among other things. Also, the analog circuits involved in these very expensive mixing boards and equipment (hundreds of thousands of dollars for the equipment in my studio) would caress, massage and lovingly process the sounds in a very pleasant way as well. The old "analog sound".   

       Now music in real life isn't pleasant to listen to. Stand next to a drum set and tell me that cymbal in your ear is music. It's pain. Analog can soothe that beast, digital gives you everything that's actually happening. So you can still make things sound pleasant with digital, you're just going to have to develop the skill to deal with all those transients and spikes that were previously smoothed over by the old analog recording gear. Analog tends to naturally sound good, digital needs to be controlled by somebody with a very good ear.   

       Anyway, big problem with digital recording and sequencing is ear fatigue. Your ears get tired of being beat up on the sonic side, and on the musical side, the mind processes perfect music repetition like sequenced drum tones the same way it processes wall paper with repeating pictures of flowers on it. It doesn't go "Flower, flower, flower, flower..." the mind goes: "Shitload of flowers." and moves on. This is the problem sometimes with very sequenced perfectly timed and especially repeating stuff, the mind processes it and gets bored of it so you need to take drugs on the dance floor to tolerate it. A drum set played by a human, a skilled human anyway, moves with the music and gives you little changes and variations that keep the brain interested rather than being a glorified metronome.   

       That's why the old stuff has survived the decades. It's sloppy, it's imperfect, it's human.   

       By the way, go see the Queen movie. I thought it was beautiful. I also personally know a guy featured in it.   

       It's not name dropping if you don't drop the name.
doctorremulac3, Jan 25 2019

       <feeling reverence> Yeah, ", nice. </feeling reverence>
wjt, Jan 26 2019

       //I wonder if anyone is writing 'sloppy' synthesizer software. If they aren't, they are now.//   

       Well as far as sound processing, there's a person I know who started a digital plugin company called The Bomb Factory that's now owned by Avid that makes stuff that completely "analogizes" (new word) stuff. These things are incredible. He carefully analyzed tons classic analog rack mount processing gear and made amazing digital clones of them. So you can purchase a plugin for a couple of hundred bucks that completely replicates the sound of a five thousand dollar classic tube compressor for instance. There's lots of these sound processing plugins of course but his actually sound good.   

       But I'm not sure how you'd "humanize" sequenced drum or sequencer tracks other than backing off on the quantization. (the thing that neatens up sloppy playing) Of course you can just turn quantization off but for some reason nobody does that. I never did. Guess it's like a gal wearing makeup. Yea, it's not natural, but if you look better with it, why not? I quantized all my percussion stuff except drum travels that sound like fire crackers going off if they're sequenced.   

       Plus playing instruments in real time and making them sound good takes talent and practice. John Bonham is the greatest drummer who's ever lived, he's the one you'd want to study to find out how to properly "humanize" or "sloppyize" sequenced stuff. That would actually be a fascinating study. You'd write some kind of program to see when and how he led or lagged hits compared to a perfect timeline. Of course it's not just timing you'd study, it's dynamics.   

       Been so long since I've been in the biz, wonder if anybody is doing anything like that.   

       Uh oh, just realized John Bonham, my number one musical hero, was English. Oh well, gotta give praise where praise is due.
doctorremulac3, Jan 26 2019

       This is a tricky area, because for a beat to groove, it really does have to be "in the pocket" as we used to day.   

       Here's an interesting experiment:   

       I actually have a pretty cool collection of classic rock songs with the individual tracks separate. Let Zeppelin and Queen to be specific. These are probably available on line for everybody these days but back when this was like having nude pictures of the pope. (As far as rarity, not entertainment value.)   

       So take one of these drum tracks of Bonzo and quantize it. Real simple to do, you hit a button and suddenly it's exact 16th notes, or dotted 16th swing notes or whatever it is. Before you did this you could just visually zoom in on a grid seeing clearly where he's off a SMPTE based timeline, if at all.   

       Does it feel less... I don't know, John Bonhamy?   

       Anyway, take that info and apply it, as necessary, to what I used to call teletype beats.   

       By the way, my dad used to have one of the machines shown in the link. I'd write "beats" that were imprinted on a strip of paper with holes in it to play beats. (link)
doctorremulac3, Jan 26 2019

       //randomize the generation of beats or notes to create an average bpm rather than strict spacing, although that random variation would only need to be fractions of one percent//   

       I don't know if randomization would help - I think it would just be subtly annoying. I know nothing about either drummers or musicians, but I do know that when [a good] one of them is a 64th of a beat late or early, it's for a reason. I suspect that knowing instinctively whether you should be 1/64th early, 1/64th late, or bang on, is what makes the difference between a competent performer and a good one.
MaxwellBuchanan, Jan 26 2019

       NEWS FLASH! Ok, just spoke the my buddy who gave me all those raw drum tracks years ago and talked to him about what makes drums "breath" or "feel natural" and told him my idea to quantize those raw tracks to see how it was effected.   

       He's already done it.   

       So what was the difference? He said, not much. But he hit me with something that sums it up so perfectly. What makes John Bonham's drums amazing? You can listen to it without any other instruments, and it's beautiful.   

       I hate to sound artsy fartsy but he summed it up. This is art. You can have a computer make a painting, or a poem, or a song but the appeal of great art is that.. sorry for this... there's something appealing about it. It may be the way singer gasps for breath between notes on a particulary passionate part, the way a writer brings all the character's stories together at the culmination of the novel, or the way an artist like Escher or Dali makes you say "How the hell did he do that? ".   

       It's not technical. It's magical. So again, what makes John Bonham great isn't the mathematics of where the notes go, it's the way he dances around the song, the way he listens to Robert Plant pausing between lines and places punctuating drum travels that take that line Robert Plant just sent a chill up your spine with and charges it with a thousand volts in case you didn't get the message, and whatever that message is, it's heavy. I have no idea what they're talking about, but it hits like a god damn lightening bolt. It's reaching right down into my soul and pulling someting out of me I didn't know I had. I don't even know what the hell it is but I want to feel it again.   

       Sorry, got into a bit of a writing frenzy there.   

       I can type very fast sometimes.
doctorremulac3, Jan 27 2019

       ANyioen can tpep faast. Doingo ti accuaratelt is waht coutns.
MaxwellBuchanan, Jan 27 2019

       OK, somebody made a great video that explains why Bonham's drumming is better than a drum machine. (Warning, for the drumming obsessed only.) See link.
doctorremulac3, Jan 27 2019

       Having not looked at video and taking all energies into the equation , a computer would be modulating the essential computer essence, abhorent to a human and probably nature herself, and Bonham would be modulating the essence of a star, an aura loved and worshiped by humans.   

       Just a left field thought, is digital communication modulating a bad essence of choppy conversation?
wjt, Jan 27 2019

       Well, I respect his drumming, not him.   

       I started to relate the two stories I had heard first hand from two different people who saw some pretty aggressive behavior from this guy but decided to leave the dead to rest in peace. I'll just comment on one because it was widely publicized, where he and his boys jumped some workers at a stadium they were playing at. My manager (years later obviously) was the concert promoter at the time and banned Led Zeppelin from ever playing in Northern California again after that incident. I just heard the gory details from somebody who was in the room. Don't want to say too much negative about the dead but he was certainly a hard case. I respect tough guys who fight face to face when necessary but jumping somebody isn't a tough guy move. I'll leave it at that.   

       It's his talent, not him I respect.   

       Hey, the Soviets put the first man in space. Sometimes when evaluating stuff you have to separate the act from the actor.
doctorremulac3, Jan 27 2019

       Sometimes the full story isn't known and from the outside looks really bad. Hopefully karma was on the case.   

       From the video, Bonham sure has that maestro subtle control with respect to drumming. I wonder if there is a physiological ratio of nerve endings to muscle fibres to give a possible unit of subtle motor control with respect to fast action. A muscle puppetry ability score so to speak. And I'm back to sampling and quantization.
wjt, Jan 27 2019

       Here's my take.   

       I believe somebody who put the effort and the soul into a drum machine could make drum parts that could make you weep, but we tend to just tell it what to do and add music on top. It's also very easy to do, anybody can do it. To make a dumb instrument like a bunch of drums sound like music takes a little skill, and I believe with the skill to make the trickier instrument make music comes the entertaining part.   

       I'm not sure if that makes any sense at all.   

       I'll read it tomorrow and see if it does.
doctorremulac3, Jan 28 2019

       How I read it, At the top end both would take an expert skill it's just that the actual instrument is a longer, steeper initial learning curve which gives more people pushing buttons than competent physical instrument users. And that the extra learning with the subtle physical interaction, musically gives the extra entertainment special source.
wjt, Jan 28 2019

       Yes, you said it better than I did.   

       That's what I believe.   

       So somebody might obviously do something amazing with any musical tool, including a drum sequencer, but put it this way. If you had a robot and said "Robot, write some amazing music and put my name on it." it might be compared with somebody who put their heart and soul into the work and that might come out in the listening. People hearing the robot written piece might say "Well, I can tell a Maestrolux 9000 piece when I hear it, but did you hear what this person did by singing while tapping on the beat on his chest? How did he make that so interesting?"   

       Easier tools might also make music available to less motivated people, and less motivated people might not necessarily make better music. Or better anything for that matter.   

       Another good example might be for singing. You can program robot voices to sing, or you could listen to the guy in the link doing this with no music. (see link)   

       Humans put emotion, whatever that is, into the music. We might ask ourselves "What's the human story behind that?" something we wouldn't ask with a machine. Unless somebody did something with a machine to prove that statement wrong which is entirely possible. How? Well, not by programming in a beat that everybody's heard a thousand times before and combining it with video images of a good looking woman singing scales with generic lyrics for the sole purpose of selling records. records.
doctorremulac3, Jan 28 2019

       Has anybody ever played a drum machine with drumsticks? Just turned it off and played it as an inert plastic box being used as a percussion instrument?   

       That would be an interesting statement. Guy pushes play on the drum machine, it starts churning out some generic beat, he un-plugs it and whips out a couple of drum sticks and proceeds to do something amazing with it. The different knobs, the LED screen, the sides would all probably make slightly varied percussion sounds. A row of buttons could be swept across like a guiro for instance.   

       Now there's an idea.
doctorremulac3, Jan 28 2019

       Speaking of classic old gear, it just occurred to me the EMU SP-12, the first commercially available sampling drum machine either came pre-loaded with John Bonmam drum hits from "When The Levy Break" or I bought that as a separate package at the same time I purchased the unit.   

       You actually had a robot John Bonham that would play any beat that you wanted.   

       I looked up a picture of this machine and got a rush of nostalgia that surprised me. I knew I couldn't compete with the big dogs of the music biz using their equipment so I made sure I was the first to use this cutting edge stuff to bust my way in. This thing was like a fucking magic carpet to me. (link)   

       Every month I'd sit and ready my copy of MIX Magazine from the back to the front to see the ads for the newest musical equipment. Oddly enough I never read the interviews with big producers and successful engineers. I was there for the news on the state of the art from the technical side. I knew (or thought I knew) nothing they had to say would apply to me anyway. Plus, looking back, I was probably jealous and hated them for their big mansions and expensive sports cars while I had a bed in an old office building that I had converted into a recording studio.   

       OK, that's enough nostalgia for one lifetime. Back to the future.
doctorremulac3, Jan 28 2019

       I had a friend that bought the first widely available commercial sampler that Emu made and I want to say it was over ten grand.
doctorremulac3, Jan 29 2019

       OK, can't find the price but I see that it replaced a unit E- MU made for $70,000. Not a typo, it was the same price as a Ferrari at the time.   

       Anyway, this guy made the studio rounds with his $10,000 keyboard charging for its use and he did appear to keep busy. We'd all gather around it like the monkeys in 2001 marveling at the monolith.   

       Anyway, I almost felt bad for him when the Emulator 2 and subsequently much much cheaper samplers came out but that was obviously offset by the fact that I could now afford them.
doctorremulac3, Jan 29 2019

       U-law or a-law encoding does something like this but for individual samples: samples with values near zero (that might be part of a low volume sound) are encoded with more precise quantisation than samples with high magnitude positive or negative values (that are part of a high volume sound). They only use 8 bits to store each sample though so they may still have more quantisation than you want - probably at least as much as a 16 bit sample without the technique. A similar idea would be to encode samples as floating point numbers.   

       One way of doing this is to digitise each sample with the minimum quantisation you might need then convert to floating point to reduce storage space. Another might be to make a direct floating point analog to digital converter, which I've never heard of being done.
caspian, Jan 29 2019

       Dave Rossum in an interview said that, when they were developing the Emulator (I or II I guess.. or maybe the Drumulator), and had to convert between different clock rates, they had much better results using a steady stream of simple + or - bits at a very high frequency(2MHz?) rather than interpolating or dropping bytes at the comparatively low rates in the 10's of k's.
FlyingToaster, Jan 29 2019

       Those guys would know about this because they're the pioneers of cost effective sampling and did this with 80s computer technology.   

       They were located close to me so you could drop a piece of gear off to be upgraded and spend the day at the adjacent beach towns waiting for it. What a friggin' cool company.
doctorremulac3, Jan 29 2019


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