Don’t fall down the stair steps! Things you may not have known about digital audio.
- Thread starter smitty_p
- Start date
Alright....couple of things...
The first video is pretty cool. I liked it a lot. Higher sample rates in audio capture will give a more accurate representation of a recorded audio source....but it becomes an exercise in picking nits at a certain point for most people. The dither demo was cool...I never ran my early dither plugs through a scope to see what they were doing, I played by ear to make my early disks.
The second video is interesting. I sincerely doubt that the file referenced was actually captured/sampled at 32 bit float. It was likely “resampled” to that bit rate by the software running. Why do I doubt the 32 bit float? Because I am not aware of any ad/da converters in a capture interface available that operate at 32 bit float. It is likely a 24 bit, or 16 bit(most likely* because that’s where the quantization noise departs-thus ”native” resolution) file.
When resampling an audio or video file upward in software the only thing “added” to it is file size(For software to recognize), and not resolution. You can not improve the resolution of a digitally captured file after the original capture. You can, however, beat the snot out of it by resampling and decreasing the file resolution...as he illustrated.
He did touch on the fact that 24 bit audio has a larger dynamic range, and that is why it has been the studio standard for capture bit depth for quite a while now. That increased dynamic range allows for more headroom to capture a dynamic audio source. Noise floor remains more manageable. It is not about loudness at all...especially when recording something like a kick drum at either 16 or 24 bit native captured resolution.
The thing is, those resolutions don’t readily reflect a large difference to each other until you start to tax their limits by mixing a whole bunch of audio tracks together.
I know that I can get some decent results when working at 16 bit. I know that I can get the same or better results from 24 bit capture.
Sample frequency rates are another whole can of worms...where perception is involved....and it becomes more evident when sources pile up(track counts get larger). The thing is, you do have to consider the fact that your song recorded at 24 bit/192kHz sample rate is going to receive the treatment that the second video illustrates a bit(pun) when he resamples the bit depth...when someone reduces the file resolution, in a way that you have no control over, to something like 16 bit/44.1kHz....with who knows what dither protocol(if any) to accommodate their playback device. That’s why most that do the recording either do the dithering and conversions themselves, or approve them from a mastering facility, for release.
I hope some of that makes sense.
Thanks @smitty_p for making me think today.
The first video is pretty cool. I liked it a lot. Higher sample rates in audio capture will give a more accurate representation of a recorded audio source....but it becomes an exercise in picking nits at a certain point for most people. The dither demo was cool...I never ran my early dither plugs through a scope to see what they were doing, I played by ear to make my early disks.
The second video is interesting. I sincerely doubt that the file referenced was actually captured/sampled at 32 bit float. It was likely “resampled” to that bit rate by the software running. Why do I doubt the 32 bit float? Because I am not aware of any ad/da converters in a capture interface available that operate at 32 bit float. It is likely a 24 bit, or 16 bit(most likely* because that’s where the quantization noise departs-thus ”native” resolution) file.
When resampling an audio or video file upward in software the only thing “added” to it is file size(For software to recognize), and not resolution. You can not improve the resolution of a digitally captured file after the original capture. You can, however, beat the snot out of it by resampling and decreasing the file resolution...as he illustrated.
He did touch on the fact that 24 bit audio has a larger dynamic range, and that is why it has been the studio standard for capture bit depth for quite a while now. That increased dynamic range allows for more headroom to capture a dynamic audio source. Noise floor remains more manageable. It is not about loudness at all...especially when recording something like a kick drum at either 16 or 24 bit native captured resolution.
The thing is, those resolutions don’t readily reflect a large difference to each other until you start to tax their limits by mixing a whole bunch of audio tracks together.
I know that I can get some decent results when working at 16 bit. I know that I can get the same or better results from 24 bit capture.
Sample frequency rates are another whole can of worms...where perception is involved....and it becomes more evident when sources pile up(track counts get larger). The thing is, you do have to consider the fact that your song recorded at 24 bit/192kHz sample rate is going to receive the treatment that the second video illustrates a bit(pun) when he resamples the bit depth...when someone reduces the file resolution, in a way that you have no control over, to something like 16 bit/44.1kHz....with who knows what dither protocol(if any) to accommodate their playback device. That’s why most that do the recording either do the dithering and conversions themselves, or approve them from a mastering facility, for release.
I hope some of that makes sense.
Thanks @smitty_p for making me think today.
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BFT Gibson
Ambassador of Originality
Master !? is that why i sense in the Reaper..or have noticed to keep my recording levels lower( way contrary to old tape days of capturing hot as possible) and then allow the digi crap to max it in the mix
to me its what killed music..no up & downs anymore...lsten to our old guys isolated tracks..not so good sounding but in the mix..awesome...not some 01000100100 junk..a,,hell the kiddies bring their crappy gear t the studio with no song & we got to fix it...re playn the stuff with real guitars & amps...then mix face dude will squash it all..i tell ya..in the next few months..onto something..its going backwards..to the old days & allow the music to speak not the mix..put the needle on the record,,it was why music was better..
That is one of the virtues of digital recording that you have a good instinct for(IMO). Slamming analog levels to analog tape, sometimes, can actually create a pleasant/desirable signal clipping, or distortion. As opposed to digital signal clipping, which is just square wave(not exactly like the first video, but in a Wav form display looks similar...without the rippling top) and extremely unpleasant sounding.
You can read all different number preferences put out by many recording people about what dB levels To aim to peak at when recording a track...and what peak levels to shoot for for a mix file that is to be mastered.
edit: most digital platforms do the up-sample to 32 bit float to increase the master mix headroom...then when you render a mix file you usually would choose the destination file resolution, with the playback purpose in mind.
BFT Gibson
Ambassador of Originality
Do you think the digitial age brought on too much compression in general across the board?
Compression has been used in a lot of the recording music since the beginning, in some fashion...from the compression of a tube preamp...to compression used for broadcast...to “the loudness wars” compression.
Loudness wars compression was, largely, limiting(signal) actually...along with compression, in an attempt to raise the perceived volume levels. Largely, this was probably fostered by broadcast systems that used compression, and limiting, to “even out” broadcast audio content.
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BFT Gibson
Ambassador of Originality
right on..the loudness wars..really pushed things up
reflected back to a project at the studio i helped on.. The paying group came in with all wrote out math parts for songs..on midi keyboard in amp sims. Not 1 guitar or bass part on it. I had my eye opening during the translation of it all to real instruments. I could pick up the emotion for them..but it went outside the structured tab they had. They wuld fight and argue if 1 thing changed.mathematically caues it looked correct n paper...they were writing doom & down tuned metal in majors..hey we can do it but you wont get the emotion...then they would push that mix up till the dynamics were almost gone.. was like what is the point..i would sit at the board & pull sliders down & re do parts & let it breathe..it got heavier with the dynamics in it..not pushed & squashed .. what a lesson on why i will never record without a real amp & guitar..my hands & signal path can control those dynamics..not much needed in the mix..1 ..2 takes & let roll on...
This is what has me curious about the Kemper thing....the users think that the tech is getting closer to the real behavioral experience of the interaction between player, guitar, and amp. The thing that can’t come out of the equation(IMO) is the interaction between the guitar, and a speaker cab of some type, operating together in an acoustic environment.
RVA
Ambassador
What would change if sent to the cab from the kemper instead of an amp since the end result is ultimately analog in either instance? Dynamics maybe? Would a comparable difference also be there with SS vs tube (I am not referring to the "warmth" of tubes, but a difference in the interaction you mentioned)?
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I’d insist that there be a speaker cab In the room because of the feedback interaction involved between the speaker, and guitar pickups. There are great moments when you may, essentially, be playing the guitar and amp and speaker AND the space in between.
If the speaker is removed from the equation, by recording directly or isolated, that interaction is removed. Sometimes that may be good. Other times it removes some of the “life” from a performance capture(IMO).
BFT Gibson
Ambassador of Originality
RVA would so love to be able to do a video with you..in interest of this very question.. Bandmaster--Plexi--DSL & the Kemper..not a competition just a swap & play all of them like tThe Pedal show & talk..exploit the best in them,,it becomes real obvious to me in a setting when they are all there..even all my amps..drastic dif of the same type amps side by side is very fun to hear
the interaction in my case is why i play..where the songs come from..why the Bandmaster this morning & a Super Reverb tonite. How they influence the playing..which opens up my creativity..
All my gear is going backwards in time that i keep, as i am done buying except pedals..most stuff here is PTP with simple circuits my ttech can fix blindflded if need be...i don't even care really what i play...but use my ears. There is not right or wrong but when you play 5 -6 hours a day & get calls to go lay down tracks in my case case..35 years of bass & 5 years of guitar knowledge is already done & ready to go..i know there is nothing new to make me sound better but me practicing
I play Kempers & digi stuff from time to time, if the rig is pre set..,my honest ..this me..is i hear it, a dif..but man i feel it in my hands when lightly tap a string, even looking for a slight echo then striking it at dif force levels or a side pick attack & having the digi sorta spit out a sterile response in relation to the strike.. also pick from the bridge to the middle of the fretboard fr desired tone..the guitar in the hand to the whole way & angle to what speaker is mic'd is crucial to me..never found a bad amp or guitar..just bad pairings...
not on the ANTI new tech side ..just know what i can pick up & get the job done without trying to get a box that attempts to emulate the real deal(that is where a some us being brought up on the tech we know will always stay with it.its know--its ingrained & proven live & studio without having to get there again or maybe get there with a new device)
Also new supposedly better Marshall.. Friedman Runt went bye bye in 10 seconds flat..in studio everyone was jacked..oh wow a friedman..like the 2nd coming or something..same cab..same everything..the DSL ate the friedman up in a mix..Runt sound better on its own at bedroomcore levels..sure did super polished well,,everything that is wrong for a live or recording situation...application is everything for us
no better..just what is better for us as individual needs for our music... do see 1 line of demarcation that is very clear to me...the gear we all revere is made to play at a band level in general for best performance...in reality music involves a drum strike to keep time..never being designed to be at low level but to set the pace for a guitar..bass...ect to follow..in Rock its at a certain level..that level is where all the mojo lives..not needed..except turn it up to intended use level.. BTW the Klon Cl rules ..lol what a great do it all pedal..
RVA
Ambassador
I get the direct vs speaker thing, but I wonder more about what is feeding the speaker
I want to test this. How is this for a comparison
- Amp at setting X though Cab A and recorded on mic Y
- Amp PROFILE of setting X through CAB A and recorded on mic Y
- Amp PROFILE through FRFR speakers recorded on mic Y
- direct recording of amp PROFILE
I know this does not account for feel, and touch sensitivity, but it may show some sound variations. Plus, I can send you the original reaper file so it is not compressed by soundcloud. I can post also post a soundcloud version. Does this sound like a worthy test for this premise?
I am interested because I have had 2 experienced musicians stress that I should save at least 1 good tube amp when they saw my amp sales (they did not know that I have 2 tube amps left, even after I sell all of those!!!)
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I’m not talking about profiling vs real amp at all. I’m talking about the feedback loop created between an electric guitar and an audible amplification system in an acoustic space(room/stage/barn...whatever). That’s all. I’m not slagging the Kemper...I’m interested in it. I’m wondering if it will provide the type of interaction that I’m referring to, In a way that is as convincing as the direct performance material I’ve heard.
Harmonic feedback...manipulation of it....as part of the performance.
I want to know if it will perform in a similar manner to the amplifiers that it seems to model so well. I wanna be able to play like I do WITH an amp. That is why I said that a speaker in the room is a must. I don’t care if it’s frfr, or some powered cab, or my monitors....will I get playable musical feedback? Without too much difficulty? In the way to which I am accustomed?
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RVA
Ambassador
Got it. And I was not trying to be a Kemper defender. I was just looking for a cool experiment.
Most Kemper videos you see make reference to a lack of an "amp in the room feel" from an FRFR, or more obviously, DI. Kemper users are very reluctant to use a traditional cab for fear of coloring the original profile. I treat this like any other amp/cab pairing....the pairing will significantly affect the end result. Kemper should not be thought of differently, but it is. By way of analogy, many Mesa amp players insist on a Mesa cab (and even tubes) to get the intended tone. Kemper has sought to address this issue with the Kemper Cab and Kemper Kone speakers (which provide other benefits like virtual speaker swaps).
If you think of an interesting experiment, let me know!
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BFT Gibson
Ambassador of Originality
RVA.. you are having fun!! That is the thing that draws me in. A studio has used my cabs to capture IR's for their use..was a fun day to hear the cabs & also really exposed what the cabs do real well
.last 24 hours..every guitar & every amp i have...just to get the gear for next song... got sidetracked between Bandmaster & Super Six.. a Behringer Tube Monster showed up mid day yesterday...whoa..just rewrote 5 years of how i approached things..always thought if fender has 1 more tube in front of it..even a crappy one.(even starved..who cares).it would radically rearrange the tone stack..sure did..my Bandmaster is pushing Mesa territory now with a simple box. Ran some expensive glass in it..the stock tube is excellent for the heavies..blues rock slap tamer tube in & the amp opened up. Leaving stock tube in..darn , tight metal mayhem in a Fender..in 1 purchase ..the heavies came back..was trying to go another route sonic-ally..but hey..gonna run with it..pleasant surprise
..but the example..the experimentation..is a lifelong journey of enjoyment. .play it..report it..compare it..share it
A direct recording of the Kemper, using a high gain model(like a Mesa, or maybe your Phaez)...
While an in room, real time, monitor is in use(not recorded-no mic-can be your monitors, or the power section and speakers of an amplifier rig etc.) at a level high enough to cause harmonic/playable feedback. The ability to let a chord ring in to sustainable feedback that can be varied by string bending or trem use.
I would like to observe the result.
RVA
Ambassador
OK, so high gain magic on a DI recording using the Kemper. You realize that it is me who will be playing, right?! I will do my best. I will send the Reaper file to you direct.