Thank you,

sg

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http://www.cycling74.com/forums/index.php?t=msg&th=18043 &start=0&rid=0&S=4938276267d0b11125605eef81787a1 c

The basic idea is that regular sends & receives do not add any significant overhead to your patch, whereas send~ & receive~ can. So if you’ve got a few hundred send~ objects in your patch, you may want to try cutting back.

No doubt there are many more threads on similar topics though..

- DL

do i need to use the “selector~” with this mute~ in a sub patcher ??? Where do I exactly put the mute~ to ???
Last time when I used the selector~+mute~, it really screwed up and didn’t work like it was supposed to. I’m very interested in this.

look at the mute~ helpfile and the turorials- it has an example.

mute~ or send enable 0 -> pcontrol

v a d e //

http://www.vade.info
abstrakt.vade.info

I LIVE! I LIVE! I LIVE! I LIVE! I LIVE! I LIVE! I LIVE! I LIVE! I
LIVE! I LIVE! I LIVE! I LIVE!

You will not be saved by the Holy Ghost. You will not be saved by the
God Plutonium.

In fact, YOU WILL NOT BE SAVED!

thxx.
oops, you are right. It was begin~ that went with the selector~.

Thank you so much for your kindness, Tristram

I’m still not sure whether the mute goes outside the subpatch or not.
So I’ll try them as soon as I get home.
Will post any patches if it is necessary.

again, thank you.

snif

v a d e //

http://www.vade.info
abstrakt.vade.info

I LIVE! I LIVE! I LIVE! I LIVE! I LIVE! I LIVE! I LIVE! I LIVE! I
LIVE! I LIVE! I LIVE! I LIVE!

You will not be saved by the Holy Ghost. You will not be saved by the
God Plutonium.

In fact, YOU WILL NOT BE SAVED!

with [selector~] you can in some situation even
turn off a subcircuit as soon as it is started
by a [begin~]

i never got mute~ to work the way i wanted so my
preferred method remains making subpatchers and setting
the processing off to the stuff inside with messages
to universal. :)
of course that can produce clicks or interrupts.

—————————————————-

My experience is that begin~ is obsolete, and that the mute~ / pass~ method is hard to deal with, and isn’t very effective.

I make a practice of encasing any processing you might want to mute inside a poly~ object, and then dealing with the mute message to thispoly~. This shuts things down much more effectively.

On thing to worry about, send~’s inside of the poly~ need to be zero-ed before you mute them.

mzed

an idea i always try to sell to people is to downsample
specific objects or small arrays of only a few things.

if i build a compressor for example, i put objects
like avg~ or average~ into subpatchers and make them
a poly~ foo down 8, because it simply doesnt matter
for the sound quality if you run power analysis at
5khz or at 40khz, but it saves 7/8 CPU cycles.

This sounds likes what I need to do. The patch I have built attempts to emulate an analog synth and will eventually become a pluggo. it includes 2 oscillators (I am using the non aliasing objects tri~ saw~ etc. which take a little more CPU), 2 envelopes, 2 lfos, and a filter section (two biquads). I am thinking that the LFOs could be one target for downsampling as well as the envelopes. Currently the patch takes about 10% CPU… which kills my chances at making the synth usefully polyphonic. I am not using and send~ receive~ pairs… and can’t think of what else to look for to make the patch more efficient.

sg

it frees up the CPU you need to upsample biquad~ and comb~ …
:)

Good approach Roman – a question though; does the downsampling action
in the poly~ eat any resources itself? I’m presuming it does, but
perhaps less than the gains you are getting from operating at the
lower sample rate…

Dan
–
Dan Nigrin
Defective Records
202 Hack / PC-1600 User / VSTi Host / OMS Convert / Jack OS X
http://www.defectiverecords.com

http://www.jackosx.com

what sorts of things do you down sample in FM synths?

sg

100 copies of [poly~ 110.polyavg~ down 8] need 12,5% of
what [avg~] would need.
what i worry more is the messages priority inside vs.
outside, i have no clue about that. for smaller subpatches
it does not really matter of course.

>simone
>what sorts of things do you down sample in FM synths?

the whole operator section for example, or an operator
section which is to be used as suboscillator.

it would contain phasor, cycle, kink, line, +, -, *, /,
delta, whatever you wish :)

you might want to use not less than 22 khz though.

>sniffio
>would this help if I downsampled at the last end of my >master-dac??
>Or do i have to use this downsample-method on every adc-inputs >?? 7/8-cpu-save sounds amazing.

adc and dac belong to the few signal objects which you
can not downsample.
if you want a 5.7 khz recording system you should get
a macintosh performa 5300 with built-in headphone jack
and system 7.0; it has that samplingrate by default.

> if i build a compressor for example, i put objects
> like avg~ or average~ into subpatchers and make them
> a poly~ foo down 8, because it simply doesnt matter
> for the sound quality if you run power analysis at
> 5khz or at 40khz, but it saves 7/8 CPU cycles.

I disagree that it simply doesn’t matter. Imagine you are analysing
the output of a sine wave with the frequency set to pi/4 radians (or
6k if your sampling rate is 48k) so that the period is exactly eight
samples. Your downsampling poly~ would then select a sample from this
sine wave at exactly the same place in the cycle every time. The
value of that selected sample depends on the phase of the sine wave -
it could be zero, it could be the full amplitude of the sine wave, or
it could be anything in between. So by placing your amplitude
analysis in a downsampled poly~ you have introduced a phase-dependence
into your compression algorithm, and in extreme cases the algorithm
could badly fail to properly analyze the amplitude of the incoming
signals.

Hi Dan,

> Good approach Roman – a question though; does the downsampling action
> in the poly~ eat any resources itself?

Currently the downsampling in poly~ is very cheap – it just selects
every Nth sample. Upsampling is similarly cheap.

Ben

Though not perhaps applicable here, I’d also recommend slide~. As far
as signal-rate envelope following objects go, it’s more CPU efficient
than rampsmooth~, and scads better than average~.

max v2;
#N vpatcher 30 89 767 785;
#P window setfont “Sans Serif” 9.;
#P number 406 295 35 9 1 8 3 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P newex 406 322 38 196617 sig~ 2;
#P user scope~ 406 395 536 525 2 3 128 -1. 1. 0 0. 0 0. 102 255 51 135
135 135 0;
#P newex 406 345 57 196617 index~ foo;
#P newex 326 147 78 196617 loadmess 4000;
#P number 270 295 35 9 1 8 3 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P newex 79 281 35 196617 sqrt~;
#P newex 79 258 31 196617 abs~;
#P number 373 188 35 9 1 0 1 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P number 326 188 35 9 1 0 1 3 0 0 0 221 221 221 222 222 222 0 0 0;
#P button 279 204 15 0;
#P newex 279 221 104 196617 pack rampsmooth 1 1;
#P newex 270 322 38 196617 sig~ 1;
#P user scope~ 270 395 400 525 2 3 128 -1. 1. 0 0. 0 0. 102 255 51 135
135 135 0;
#P newex 270 345 57 196617 index~ foo;
#P message 253 67 73 196617 sizeinsamps 8;
#P newex 253 93 61 196617 buffer~ foo;
#P newex 34 349 53 196617 poke~ foo;
#P user ezdac~ 55 412 99 445 0;
#P newex 80 55 76 196617 count~ 1 8 1 1;
#P newex 80 238 119 196617 selector~ 8;
#P newex 35 308 58 196617 vectral~ 8;
#P newex 185 215 58 196617 cycle~ 0.8;
#P newex 171 196 58 196617 cycle~ 0.7;
#P newex 158 177 58 196617 cycle~ 0.6;
#P newex 145 158 58 196617 cycle~ 0.5;
#P newex 132 139 58 196617 cycle~ 0.4;
#P newex 119 120 58 196617 cycle~ 0.3;
#P newex 106 101 58 196617 cycle~ 0.2;
#P newex 93 82 58 196617 cycle~ 0.1;
#P connect 8 0 12 0;
#P connect 10 0 8 0;
#P connect 18 0 8 0;
#P connect 10 0 12 1;
#P connect 10 0 8 1;
#P connect 9 0 22 0;
#P connect 22 0 23 0;
#P connect 10 0 9 0;
#P connect 23 0 8 2;
#P connect 0 0 9 1;
#P connect 1 0 9 2;
#P connect 2 0 9 3;
#P connect 3 0 9 4;
#P connect 4 0 9 5;
#P connect 5 0 9 6;
#P connect 6 0 9 7;
#P connect 7 0 9 8;
#P connect 14 0 13 0;
#P connect 24 0 17 0;
#P connect 17 0 15 0;
#P connect 15 0 16 0;
#P connect 21 0 19 0;
#P connect 20 0 19 0;
#P connect 19 0 18 0;
#P connect 25 0 20 0;
#P connect 20 0 18 1;
#P connect 25 0 21 0;
#P connect 21 0 18 2;
#P connect 29 0 28 0;
#P connect 28 0 26 0;
#P connect 26 0 27 0;
#P pop;

Mathematically you’re right. From an engineering perspective, you’re
talking about an extremely unlikely occurence, one that can happen with
carefully (perversely) constructed generator signals and almost never
with real world signals.

If you know you have a cycle~ at pi/4 you don’t normally need to take
its average~ .-)

Downsampling a signal before passing it through average~ has the add’l
advantage that you extend the (real) time before average~’s propensity
to cumulate errors becomes an problem.

You’re absolutely right that people should be aware of the traps
involved in downsampling. It ain’t a cure for all ills. But it can be
very useful.

> Currently the downsampling in poly~ is very cheap – it just selects
> every Nth sample. Upsampling is similarly cheap.

This is good to know. Is upsampling linear interp, or are you just
repeating samples?

– P.

————– http://www.bek.no/~pcastine/Litter/ ————–
Peter Castine | ^
| Litter Power & Litter Bundle for Jitter
pcastine@gmx.net |
pcastine@bek.no | iCE: Sequencing, Recording, and Interface Building
4-15@kagi.com | for Max/MSP
| Extremely cool
| http://www.dspaudio.com
| http://www.dspaudio.com/software/software.html

thanks Ben, good to know what I presumed is in fact correct.

Dan
–
Dan Nigrin
Defective Records
202 Hack / PC-1600 User / VSTi Host / OMS Convert / Jack OS X
http://www.defectiverecords.com

http://www.jackosx.com

> I disagree that it simply doesn’t matter. Imagine you are analysing
> the output of a sine wave with the frequency set to pi/4 radians (or
> 6k if your sampling rate is 48k)

wow your example is valid, i have not been thinging
about that. i was only aware that there is a slightly
inaccurate analysis result on very high frequencies
which i decided to ignore. :)

in real life the chance that a piece of music contains
a moment of pure 6 khz sinewave sound tends to zero though.
and if there is one, the sinewave will probably be of
only a very low volume.

hmm. but now …
how is that with 44.1 khz? …

you could as well have a 6 khz pulsetrain-like waveform
coming from an 88.2 khz oscillator, and when you average
it in 44.1 khz mode the problem appears again; in
exactly the same manner like you described it, and with
the same deviation, leading to a 100% wrong result.

in poly its repeating.
not a big deal to apply interpolation when needed. :)

it was worth the thread. i learned here it that
mute~ works with poly~ better than with patches
and i will handle this knowledge with care.

-110 (yet more efficient)