[linux-audio-dev] XAP: a polemic

[Tim Goetze]

David Olofson wrote:

>> [TIMEBASE, aka ppq]

>> the only thing i object to is that you want to assign a fixed
>> value. it is a severe limitation, but it gains us absolutely
>> nothing. at least you don't give a reason why it needs to be
>> fixed.
>
>If it's not fixed, it's another parameter you have to get from the 
>timeline, before you can do anything useful with a musical time 
>value. That's all, basically.

for the timeline, not from. 

it is constant throughout in a sane system.

>> >> please, please, please, ask your favourite musician friends.
>> >> read good books about it. listen to indian, jazz, techno,
>> >> blues, classical western, classical indian, japanese, rap,
>> >> whatever music: rhythmn is integral.
>> >
>> >Well, which ones qualify?
>>
>> all of them.
>
>Well, you've already disqualified at least one on this list, I think. 
>(And I don't count myself, of course.)

which? i'll remind you that 9.5 = 19 / 2 -- that doesn't prove
me wrong.

>> rhythmn is always based on one integral periodic 'pulse'. if
>> time is not divisible by this atom, there is no musical time.
>
>>From a theoretical POV, I would agree, but that doesn't seem to be 
>the best way to think of it at all times.

it is not theoretical. it is the practical foundation of
musical time.

>> >If you really *want* a bar that's shortened by a fractional beat
>> >(which is not all that unusual, even in pop music), what do you
>> >do...? How do you ensure that plugins that beat sync don't freak
>> > out when you multiply the meter to get integers?
>>
>> if you shorten, for example, 4/4 by 1/16, it's 15/16.
>
>Yeah - but then your beat sync'ed effect suddently switches from 4ths 
>to 16ths...

why should it? it knows what time unit it is synced to, doesn't
it? at least that usually is one of its prime parameters.

>> if you want to shorten 4/4 by, say, 1/16 + 0.00212266328763,
>> you're violating the very principle of the organization of
>> musical time.
>
>Well, I can't say for sure. All I know is that I do that kind of 
>things by "abusing" the tempo map instead, since that's the only way 
>you can do it in most sequencers.

this method works better:
>
>> you're better off simply inserting a new meter
>> where the shortened measure ends.
>
>How would you do that? The meter just defines the subdivision of 
>musical time. You can't just make a "skip" in musical time - unless 
>you're seriously suggesting that this should be implemented as a 
>transport "jump" to skip the last part of the shortened measure. 

not at all. but you don't have to complete the current 
measure to put in a new meter, do you? it's just a way
to count the passage of time, it's not time itself.

>> and what seems to be the problem with beat sync? the relation
>> of the meter to TIMEBASE is part of the tempo information, so
>> all info you need, you have.
>
>No. Where did the *real* beat value go?

there is no *real* beat value. if your arpeggiator starts 
emitting 8th notes when switching to 4/4 from 7/8, i'd say 
there's something wrong with it. anytime you introduce a
new meter, you introduce a new "one" beat. your plugin 
absolutely needs to sync to that, right?

and there's no *real* beat value because in the case you 
mention, you explicitly destroy musical time periodicity.

>> please excuse the harsh word: your assumptions about these
>> fields lack in realism.
>
>*heh* Well, you seem to have all the right answers - so why do you 
>tend to ignore the questions that cannot simply be disregarded as "in 
>conflict with traditional theory"...?

please put them here; i honestly don't know which questions
you are referring to.

i would love to have more musicians actively participate in
this list but there seem to be few.

>I think fp arithmetics have more effect or accuracy than traditional 
>ways of thinking about meters - but I must be wrong, then.

they are simply not adequate in this context.

tim