Question about kit piece editing in AD2

Had to take a look (been a while since I goofed around with the kitpeice editing).
 
So the main thing to know about this section is that it deals with incoming MIDI data and how it serves up the samples available for that kit peice.
 
If you don't know a lot about MIDI and how samplers work then this might be a bit confusing.
 
In fact... screw it. I'll just type up MY dumbarse understanding of the situation.
 
So when AD2 (the sampler) receives a MIDI note message (either from an external controller or from a MIDI track) it needs to take that note's data and find an appropriate sample from the audio files for that kit (those audio files are the "samples"). In AD2 those "samples" are recordings of a real life kit being struck in different ways, one hit at a time. eg: A snare being hit quietly is one sample. Then being hit a little louder second a second sample. So on and so on up to the sound of a snare being hit as hard as the sampling artist/musician can muster the strength for.
 
Then those sample files are given special names to organize them in a logical way. Like quietest to loudest. This is only one example that pertains specifically to drum samplers (those files could be ANYTHING and arranged in any way... doesn't matter but that wouldn't make much sense for a drum sampler as you will see). For a set of drum samples that are to apply to a specific kit piece in a sampler that are recorded quietest to loudest the intention is to tie those to MIDI "velocity" instructions.
 
Velocity is a special MIDI instruction. Some people think it just means "louder or quieter" and in most sample banks/virtual instruments that is KIND of the case. But really it is just a numbered instruction system that goes from 1-127 and can be programmed into any MIDI note along with the "note name". The only reason that USUALLY "note velocity" will increase volume is because some fancy programming has been done so your "virtual instrument/sampler" reads that "velocity" data for that specific MIDI note then goes into a folder that contains the "sample", looks for the correct file name (which it is told by that special programming magic I referred to), snags it and serves it up to the "virtual instrument/sampler" which then plays it back as audio (which then goes to Sonar or wherever you have the output of the sampler routed to).
 
Now a note on the fancy "programming" stuff I referred to because I think it's really the link in this chain that is the most mystifying for most (and certainly was for me until I learned about it).
 
You don't need to understand the various coding involved to know/appreciate what that code is doing.
 
The deal is in between your MIDI data (whether it be live input from an external MIDI controller or from a MIDI clip in a DAW), your sampler (in this case AD2) and the actual audio files/samples something needs to happen to tell your sampler program to retreive the correct audio file and serve it up. That of course is what a program like AD2 does. It takes the MIDI instruction from wherever it's coming from, finds the appropriate file and the plays it.
 
BUT just a MIDI note number and a velocity number (or any of the other possible MIDI transmitted data) means nothing to a sampler UNLESS it knows what the user (you) wants that data to mean (essentially what file to retreive and play).
 
So fancy programmers type up a bunch of fancy code (and there are standardized version of this code that work with various samplers and there is "proprietary code" that can only be read by specific programs... AD2 is one of the latter). They create instructions to tell your sampler (in this case AD2) that when it receives a specific "MIDI note" instruction to dig down into the audio/sample folder and retreive the sample that the programmers designated to that specific note. In AD2 this would mean serving up a sample for a specific kitpeice for the currently loaded kit.
 
But we also have a dozen or more (or less) samples for that specific kitpeice (which is tied to/triggered by that specific MIDI note). Going from "soft hit" to "loud hit".
 
THAT is where the "velocity" instructions come in.
 
So in that code (which is generally just a text document) there will be instructions stating more or less that...
 
If the MIDI note received = C0 then go to sample folder "X"
 
If "velocity" of that MIDI note C0 = 1-10 (remember we only have 127 "velocity" options) then within folder "X" retreive the file that has been associated with C0 Vel 1-10.
 
If "velocity" of MIDI note C0 = 11-20 retreive file associated with C0 Vel 11-20
 
...and so on.
 
So it goes like this (if we use a keyboard controller but MIDI clip notes contain the same data)...
 
1) Hit the C0 note on your "velocity sensitive" keyboard controller. If you hit it soft maybe it will transmit a "velocity" reading of Vel 1-20. If you hit it hard maybe it will be Vel 70-100. As hard as you can Vel 100-127.
 
2) That MIDI data gets received by your computer and whatever programs you have the data running through in between the OS (like Sonar) and the target sampler (AD2 in this case).
 
3) Once that MIDI note (C0 in our example) finally hits our sampler (AD2) the sampler takes that MIDI note, it's velocity (and any other associated instructions with that note) and tries to figure out exactly what it is supposed to do with that information.
 
4) At this point it relies on those coded instructions to take that incoming MIDI data and serve up the correct file. These instructions will generally be part of the "kit/sample" program (as far as I know).
 
5) The sampler (AD2) reads the instructions for that particular kit/sample set which tells it to pull a specific file from that sample set based on a) what note/velocity was received and b) what the instructions say which "sample" specific note/velocity value equates to.
 
Whew... that's a lot of werds but hopefully it made sense.
 
*NOTE: If you want to see an example of these coded sample serving "instructions" I keep referring to look up what an ".sfz" file is and how it is written. AD2 does NOT use that format (as I said it is proprietary to XLNAudio) but it is a long used format for this type of sample serving by virtual instruments (such as drum samplers... and Cakewalks Session Drummer 3 actually uses them IIRC).
 
One more point needs to be made before we get to what the "Response" controls do in AD2 (I'm building up to something here).
 
So now we (hopefully) understand the relation between the MIDI notes, their velocities, the sampler and how it interprets the incoming MIDI data.
 
Now here's the thing. Most sample banks (like a drum kitpeice in AD2) that are velocity sensitive are only going to have a certain number of samples for a specific note/sound. It could be six. It could ten, it could fifty, it could be 127 (127 would be the max).
 
Since we have 127 "velocity" options and trying to record 127 actual samples for EVERY kitpeice each just a LITTLE bit louder/harder than the last is not only impractical but unnecessary what happens is whoever the sample engineer and/or software company is makes a decision as to how many samples are needed for a "realistic" sound and "response".
 
So a crummy drum sample pack may have only six different samples to draw from based on velocity. I really good one might have a couple dozen. Some samplers/instruments may only have ONE sample per note (sometimes intentionally).
 
The point is since we have 127 velocity options for EACH note received and a velocity sensitive keyboard or other input method (including MIDI clips) are going to be able to transmit all 127 vel values at a given time a decision has to be made by the sampler.
 
More simply how do we divide 6 or 12 or 50 velocity values into 127?
 
That again is where that special bit of programming/instructions comes in.
 
In those instructions (and let's work with 3 available samples to keep things easy) it will say something like this for a specific MIDI note...
 
If velocity received is 1-40 retrieve sample 1
 
If velocity is between 41-100 retrieve sample 2
 
If velocity is between 101-127 retrieve sample 3
 
Of course as noted earlier in this example 1 would generally be a softer sample, 2 a medium sample and 3 the loudest/hardest sample.
 
Right? So it all depends on those instructions and the samples available.
 
*** This is a momentary sidetrack to this concept but I think it is important and does relate to the AD2 control in question.
 
So what happens when we only have 3 samples but they are divided amongst the 127 velocity options as described above?
 
Well generally when a sampler such as AD2 only has minimal sample options (and seriously I've never seen a sample bank that has 127 samples per note. That's insanity but I'm sure someone's done it) what the sampler/instrument will do is increase/lower the "volume" of the sample being served up.
 
So in our example above if we played our MIDI note with a velocity of 42 it would serve up sample #2. Since it is near the lowest end off the velocity spectrum though the sample would be played more quietly. As in the sampler would lower the output volume. If we played the same note at a velocity of 60 the sampler would play the same sample louder. At Vel 80 even louder and so on.
 
Now that is NOT true of all samplers and I think it depends on those fance instructions again but it's important to note. This is done to create a feel of dynamics/realism based on the incoming velocity despite a small number of samples. Of course the more quality and thoughtfully programmed samples you have spread across the entire velocity range the more realistic things will sound (which is especially important for a drum sampler such as AD2).
 
One FINAL note (which applies to a specific control in the "Response" area of AD2) is that many sampler style instruments (such as AD2) will have options to prevent the same sample from being played twice in a row EVEN IF the received note is the exact same velocity as the previous one.
 
So in our example above (where we only have 3 samples available) if AD2 received two consecutive MIDI notes with a velocity value of 127 it would not play sample #3 twice in a row. It would play one of the received notes as sample #3 and the other as sample #2.
 
That is a GROSS oversimplification of what's happening but that's the gist.
 
These types of random sample serving functions by a sampler/instrument are referred to in different ways so it can get even more confusing. Look for settings, terms, etc that are called "Anti Machine Gun", "Round Robin", "Randomize", etc. Check the manual for the specific sampler/instrument program.
 
In OUR case with AD2 there is a button in that "Response" section labelled "No Alts" and I believe by turning that on it will disable this random sample serving action for that kit peice in AD2 (so if you click it and your snare receives two hits with identical velocities it will NOT alternate between other samples available but instead play the EXACT sample for that velocity value).
 
Ooooooookay....
 
So all THAT said this is what (more or less) the controls of that "Response" section in AD2 do...
 
The most important control is that vertical bar of segmented lines with the little arrows at the top/bottom. Click on those arrows and drag them up and down and you will see the vertical bar getting smaller/larger.
 
What you are doing by moving those arrows is constraining the samples that are fed into AD2 based on the velocity received.
 
So if you move the bottom arrow upward (taking away segments from the bottom of the vertical bar) what will happen is if AD2 receives a really LOW velocity MIDI note instead of serving up the sample that would normally be played for that velocity value it plays one of the louder samples instead.
 
Essentially it interprets anything BELOW a certain velocity value (as dictated by the position of that bottom arrow) that is incoming as a HIGHER velocity value.
 
In our example above if you moved that bottom arrow up far enough it would reject all incoming velocity values BELOW Vel 41 and instead treat them as if they were a velocity value of 41+ thus serving up sample #2 instead of sample #1.
 
This is useful if you have played or programmed certain notes more softly (with lower velocity) than you actually want to hear. By bringing that setting UP then all those quiter samples are replaced by the louder samples.
 
Conversely if you don't want the LOUDER samples triggered by high velocity notes then drag down the top arrow and it will constrain the maximum velocity value receive and played back.
 
Kepp in mind (and this is kind of screwy) this ONLY affects the INCOMING MIDI data. Essentially it just changes the notes coming INTO the sampler which then affects what samples are retreived. Only the incoming notes... what happens to those notes AFTERWARD is a different step in the chain. No need to worry too much about that but it's something to ponder.
 
I've already described what the "No Alts" button does but again it just means (when it is NOT activated) that when the sampler recieves two (or a series of) notes that are the exact same Note/Velocity value the sampler will serve up alternating samples in the same general velocity range (or if two or more samples are available for that EXACT velocity value it will alternate between them). Once you activate that button then it will NOT alternate between samples but instead play the same sample twice.
 
The "Volume" control I think just turns up the output volume of the samples in general. I'd have to look it up but IIRC that is all that does.
 
The "Filter" control I will definitely have to look up again (and likely will and edit this entry) but I THINK what it does is excludes incoming MIDI notes based on some paramater or other. Like maybe the speed at which they come into the sampler to avoid double triggered notes and what not (so if your MIDI controller played two notes at approx the same time it would ignore one of them). Serious I am not sure.
 
Okay... so I hope that helps someone somewhere even if it doesn't ENTIRELY answer the actually AD2 question.
 
Cheers!
 
 

Beepster
I was going to provide a brief answer

 
That would be a first...