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Pb with spat.oper "Pres" parameter

Spat
#1

Hi there, I’m asking to the forum after inspecting carefully my patch, I don’t have any order sent to oper but:

whenever I clic and drag a source to control it, the presence parameter rise to 120, it breaks all the spatialisation… And, funnier, oper can drop the same presence parameter to 0, and it seem to be randomly, in it’s own decision.

Do you’ve got a clue ?

It might be my mistake, but I really can’t see a conflict in my patch…
However I manage to record and playback automation of the movements of my sources with a collection system, which I joined.
I’m routing the sources with the abstraction of mister T. so that there his only one source recorded by collection object.

So, for me, it’s another bug caused by the “mousedown” on the spat.oper, but… weird

I hope I’ve been clear in my explanation.

Cheers, Augustin

ToForum.zip (4.66 KB)

#2

Hi,

I’m sorry but i dont quite understand what the problem is.
Could you please provide a more detailed patch (+ instructions to reproduce the issue) ?
And could you please clarify “oper can drop the same presence parameter to 0, and it seem to be randomly, in it’s own decision” ?

The “source presence” factor is related to the distance of the source (also with respect to the attenuation law i.e. drop/drop mode/radius);
so when you move the source, its presence may vary. This is a normal behavior.

Finally, you can have a look at tutorial #18 which presents a patch for recording/playing back automations stored in coll files.
(although I must admit this patch is quite old and dirty…)

Cheers,
T.

#3

Hi T., sorry to disturb you again, let’s make it quick and precise !

So I’ve got a spat oper with 15 sources, when I don’t playback or record anything there is no problem.
But when I toggle the recording of 1 source movement (which I want to do straight with my mouse), I start the Master Transport, and then when I click on the source: the presence parameter rise to 120 (I didn’t even moved it in the space, it was at 60, I simply click on it and it’s 120).
And an other weird thing: when I move it somewhere the same presence parameter drop at 0 whereas my movements didn’t induce that at all.

I tried to make you a patch with only 1 source oper, but the problem wasn’t reappearing, I must join you the big patch but you’ll feel it odd and dirty as well sorry :confused:

I looked up your abstraction of recording collection, we didn’t made the “indexing the collection” the same way, I don’t know which way is the easier… You managed to turn all the sources a symbol while I prepend the index-number before the parameter list.

However, do you think it is better for me, for what I want to do, to use only the viewer ?

ToForum1.zip (452 KB)

#4

I just tried the automation abstraction with another patch, with 10 sources on a single spat object, there is no problem.
I expect the problem to be in the routing of sources, and the several spat objects…

#5

OK, I understand.
Nice catch : there is a bug when using a drop < 0.
And you are using drop = -10 dB. Is it intentional ? (such drop factor is “anti-natural”).

The bug is fixed for the next release.
Let me know if you need a fix version beforehand.

T.

#6

Great, Good Game !

Okay, actually I was looking for this artificiality, I already had 3 really different and typical reverb as sources and wanted to identify them as pad/lead more than a field.

If I use a drop at 0db, is it only a send without attenuation or simply a cut to ignore reverberation ? Although I could check that in the manual…
If it is the cut I think it’s alright for me. If it’s sending to the reverb anyway, it’s a bit more annoying.

It’s a work I have to finish for the next week, I was waiting your post to look for a solution. If you can get me the new realease before it’d be nice but it’s okay if you can’t !

Thanks again
Augustin

#7

Attached is a fixed version of spat.oper (compatible with Max 6.1).
Please let me know if this solves your issue.
Sorry again for the inconvenience.
T.

spat.oper_.mxo_.zip (2.67 MB)

#8

Hi T.

Thanks for the object, yes the problem is solved !
However, I realize that when the drop parameter is -10db, the presence seem to evolve in the inverse way than when droop is like 10dB.
To be clearer, in consequence of the presence parameter, when you’ve got the drop at -10, the sound seems louder when you move it away, is that alright ?
So it’s really not only a “reverb send”…

#9

Hello Augustin,

I’m glad your problem is solved.

Yes, a drop of -10 dB makes the presence increase when the source moves further away;
That’s what I meant in my previous messages when saying it’s « anti-natural ».

The drop factor is not a reverb send.
There are some relations between drop/drop mode/radius/source presence and distance.
These relations define the attenuation law that affects the source signal.

A drop of 6 dB (with logarithmic scale) corresponds to a natural attenuation law. Namely this means that the direct sound is attenuated by 6 dB each time the distance is increased by a factor of 2.

In Spat, the reverb is segmented in four parts corresponding to direct sound/early reflections/late reflections and late tail.
As a consequence, the notion of « reverb send » is more complex than with most reverb softwares.
The « room presence » factor is probably what you expect to be a « reverb send » as it controls the amount (i.e. gain) of late reverb for each source.

I hope this clarifies.

T.

#10

Hi T.

This soft is getting wider & clearer thanks to you.
I finished my work and I’m really satisfied of it, thanks again for your time !

Hope I won’t need help anymore,

Cheers
Augustin