Interesting Polyphony Problem?

[stevel]

So I've been working up "Every Little Thing She Does is Magic".

Since there's no decent "octave piano" I can find (and I have to switch in places) I'm using two of the same piano patch - just good old #1 on channels 1 and 2.

I'm also covering the Fretless Bass part (Look Ma' No Frets patch) and the synth line (SynBrass) that parallels it two octaves higher but continues to rise.

This is actually working great except that the synth is in 5ths every other time (because I'm going back to the lower bass note that doubles it).

I could sequence it but it sounds OK.

So I'm using sustain pedal to let the piano notes ring together and kind of lazily hold that Bass and Synth note.

But I just noticed an odd thing - the Bass note - but not the synth! will cut off after I play about 5 notes on the piano parts (so the bass and synth are essentially LH and the two pianos RH).

You would think it was a Polyphony issue.

But if I hold the note, it seems OK.

I also tried a couple of other basses and all but the GM bass does it. In fact, any synth bass actually sustains as you'd expect too.

I tried turning off one of the pianos and it took like 7 notes before it cut off.

But bassically (pun there, see it...) if I don't hold the key down throughout the measure, the bass note gets cut off.

Strangeness...

[bennyseven]

Hello Stevel,
please look here for questions about polyphony:

viewtopic.php?f=55&t=48574

[stevel]

Thanks Benny - I pretty much understand all this - but maybe it's my not completely understanding how the FA is handling it.

So, it seems like the Bass sound is the only one cutting out.

Why?

I'll check later, but is it becuase the partial reserve is lower on that particular channel?

I'm not using Channels 14-16, so I could theoretically rob from them to give to the Bass?

On my very old roland synths, I used to get a chart that showed me how much polyphony each sound used.

That would probably be impractical for a synth like the FA with so many sounds, but do you know of any general average number things like SN-A sounds use?

I'm not wedded to these particular sounds and would be fine with finding PCM versions if they use lower polyphony than the SN-A (or other SN sounds).

It's just interesting to me that a keyboard with 128 not polyphony would be bogging down with two pianos, a bass, and a synth, and that the bass note is the one that's getting cut, and not the synth or one of the other pianos (the synth and bass line are being played the same way).

It also only happens with the sustain pedal, not if I hold down the key - so that kind of makes me think it's something beyond the polyphony.

Still, I know some of these modern sounds can be polyphony suckers.

But if I can fix it with the partial reserve, that would be ideal (so I can be lazy and lift my finger ;-)

[Gatorjohn]

My guess would be - last in first out. You could as an experiment rearrange a SS and see if the "new" last tone cuts out.

[bennyseven]

Maybe it is legato and it is not a matter of voice consumption but a note on/off problem with a legato bass. Is it right that you had the problem not with all the bass sounds.

[stevel]

Maybe it is legato and it is not a matter of voice consumption but a note on/off problem with a legato bass. Is it right that you had the problem not with all the bass sounds.

Well, just to try it, I put the voice reserve up to 4 on the bass part and now it's fine.

It does have a legato thing so I had to be careful about restriking the key, but I was aware of that.

The voice reserve at 4 did the trick.

When I add the 2nd synth note in, it was then dying off so I upped its reserve to 4 and now it's fine as well.

But now I can be lazy and use the sustain pedal to hold the notes and lift my fingers off the keys early (which also helps in restriking the key for the bass notes).

Good suggestion Benny! Thanks.