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[dhjdhj]

I have a Combi that consists of piano, strings and choir and I use them in various combinations, sometimes off using Mute, sometimes off using Volume slider, etc.

I have noticed though that I don't get as much polyphony as I would have expected. If I play a few ascending chords, holding the sustain pedal down, even with just the piano (and the other two muted), the lower notes disappear quite quickly, as if the total number of simultaneous notes was only around 16 or so. There's only one reverb effect.

Am I missing something?
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[danatkorg]

[Mike Conway]

[jg::]

[jgsidak]

Does this means that one can or cannot enhance the polyphony of the Oasys by adding RAM? If so, can anyone report on how successful this fix is?
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My website contains more than 150 songs recorded on the OASYS in a variety of genres--from hard rock and jazz to orchestral and country. Please visit: www.gregorysidakmusic.com

[Kevin Nolan]

Unfortunately a RAM upgrade has no affect on polyphony. It's purely for loading samples. Perhaps Dan might point to other OS speed enhancements with extra RAM but I don't remember Korg flagging it improving polyphony.

Of course polyphony is a universal problem and not unique to OASYS, which, remember, starts from a higher voice count than even the latest Motif's and Fantoms.

Also - latency is significantly less an issue on OASYS even with high voice count - than with the likes of NI Komplete and Arturia synths on even the latest MACs. I'm confident you’ll not get 48 note polyphony from Arturia's CS80V even on a high spec mac; and expect be also able to do anything else. Korg went to some lengths to optimise efficiency, giving a large polyphony advantage over many VST/AU soft synths even on multi processor machines.

Even for the HD-1, ESx1|2|3 samples, given they are RAM based, they respond faster at higher polyphony than the best streaming sample playback libraries (I know that’s a limited comparison because of the greater no. of articulations and instrument choices available in dedicated libraries) .

So while the OASYS has a polyphony limit, it is still higher than even very well spec'd DAW setups and with lower latency. What OASYS delivers in these departments should definitely not be taken for granted – it’s not perfect but it’s a significant advance on other keyboards and as said even many DAW setups regarding the combined issue of polyphony+latency.

You'll just have to plan you combi's / song templates - but even large studios and orchestras have to plan in this way also. Resources are always limited!!

Kevin.

PS - the new Roland GAIA - with 64 voice polyphony for a virtual analogue engine - and again with essentially zero latency - is a very interesting development in this regard IMO. I know it's regarded with mixed feelings, but boy does it seem to have a quite capable engine under the hood for such an innocent looking little synth.

[jgsidak]

Kevin,

I'm glad you straightened me out on this RAM question before I went to a lot of effort adding RAM in the hope of trying to fix the problem of tracks dropping out in polyphony-rich songs.

Does anyone know whether their is a simple chart that shows how quickly one exhausts the polyphony of the Oasys with respect to different parameters?

Also, is there any indicator (like an indicator of the remaining storage capacity on a disk drive) that tells you how much polyphony you have left? I realize that it would peak across time throughout the song, depending on the arrangement, signal processing, etc.

Ultimately, what I am trying to identify is the answer to this question: How must I modify my style of composing on the Oasys to minimize the likelihood that polyphony will become a binding constraint? I want to avoid the situation in which I have invested a lot of time on a project and then suddenly realize that it will never sound the way I had hoped because the necessary polyphony will never be available.

Greg
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My website contains more than 150 songs recorded on the OASYS in a variety of genres--from hard rock and jazz to orchestral and country. Please visit: www.gregorysidakmusic.com

[Kevin Nolan]

I'm not sure such a clear cut chart could ever be derived because the amount of polyphony left depends on the number and complexity of programs used to that point.

A few pointers which I've picked up here from the likes fo Dan and Mike, and realised myself include:

1. Reduce / optimise effects in Combi's and Songs. Less effects means more polyphony for synths. Note the %indicator in the effects section, telling you how much of the available DSP is used by effects and synths. Switching effects off is not enough - you need to remove them from the insert, master or total 'slot' they occupy.

2. I think the following list indicates increasing demand on available CPU power, meaning less polyphony all round:

HD-1 [EXs1|2|3]
LAC Polysix
AL-1
MOD-7
STR-1
LAC MS20

In other words - for maximum polyphony use HD-1 sample sounds and the Polysix for synth sounds where possible as first choice; and use MS20 sounds as a last option (or less frequently).

I'm not sure if the order above is exactly correct (perhaps MOD-7 and STR-1 order need to be reversed?). Also - not sure how to judge the polyphony hogging by CX-3 engine - I think that when you activate it then it activates oscillators across 88 keys whether you're playing them or not - but that might be only when you've actually triggering the engine - Dan - could you comment on this?).

Other issues to note in Combi's and songs include:

- All of the advice given above by Dan and others - get a feel for all these issues in your Combi's and templates.

- Check if a program to be incorporated into a song uses Unison mode. If the voice uses even 2 note unison, then every note played doubles the voice count for that one note.

- For piano sounds, use the Internal pianos (especially the excellent programs provided inthe HD-Expansion packs) rather than the EXs2 Pianos which often use more layers and may not be needed in a mix.

- Same goes for woodwind and brass - use internal programs instead of EXs3 where possible.

- Only load the programs into a Combi on an as needed basis, rather than filling up a Combi/Song Template with 16 tracks of programs.

- If using the OASYS standalone, you might consider adding another synth/module to your setup and feeding into OASYS MIDI/Audio channels. Options here include everything from Korg’s incredibly cheap Monotron for synth leads to something like a Roland JV2080/XV5080 with added cards for various genres. I find these to be still exquisite modules - especially the XV5080 - its a monster and would substantively solve your polyphony issues (another 128 voices across a huge array of stunning programs).

Other than this, its a matter of getting to know Combi's that in the past worked well and using variants of these in future songs where possible.

As said before, we all have to deal with polyphony issues - this isn't unique to OASYS - I know you know this. Its not worth getting too upset by the OASYS's limitations - instead accept them, use them to your advantage and optimise / add resources as suggested above.

In the past this issue was a big one for me - the JD800 was/is central to my setup so I bought several of them. Similarly, the SY77 and 99 are quite limited polyphony-wise but interestingly, some of my compositions on their sequencers produced the dropouts you mention and in a few pieces actually added a dimension I hadn't planned but which worked out well (for a few of them in any case).

Kevin.

[jgsidak]

Thanks, Kevin.

A couple further questions:

1. Does limiting the keyboard zone for a particular program in a Combi free up CPU capacity and thus conserve polyphony? If I have a program for the bass line, should I always limit the keyboard zone for that program to the bottom half of the keyboard (or more)? Will that reduce the "dropout" problem? If I rarely play in the top octave of the 88-key keyboard, should I chop off that zone for all tracks?

2. In terms of loading only programs into a Combi on an as-needed basis, how do I keep a track unused? By assigning the default I-A000 Oasys Piano to the track?

Thanks for your great advice.

Greg
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My website contains more than 150 songs recorded on the OASYS in a variety of genres--from hard rock and jazz to orchestral and country. Please visit: www.gregorysidakmusic.com

[nitecrawler]

One other way to free up polyphony is to record some of your sequenced voices as an internal audio stereo pair that plays in sequence with your sequenced song. Although it is critical to get your mix right, balance and proper programs, etc.; the process will enable you to even get more than 16 parts down on the song. That is if you are trying to do everything within the Oasys realm. FWIW

nitecrawler
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[danatkorg]

[danatkorg]

[Kevin Nolan]

Hi Dan -

Just for clarity - if a program uses two velocity layers for example - are two voices being used, no matter what velocity you hit the key?

And - I'm now confused by something you wrote in you post. I was under the impression that if you reduced the effects count in a Program, Combi or Song, then this provided for more voices allocation, ie, greater polyphony. Are you saying this is not the case? If not the case, I must confess to being confused - what's the % indicator telling us?

Note also that it was me who flagged/suggested the use of internal pianos, woodwind and so on where possible - rather than EXs2 Pianos or EXs3 in particular. I didn't explain well - I was just suggesting to target internal programs 'in a mix' where there may be fewer layers / oscillators (on the average) in interanl programs than in the EXs ones which are (on the avreage) more complex in their programming and usage of voices. Without looking at the OASYS right now, I know for example there's one excellent acoustic piano from the HD Expansion pack, I think its called 'Natural Acoustic' or something like that, that I think has only one layer and really sounds excellent. So I was suggesting that using that Piano, for example, rather than an EXs Piano with perhaps two oscialltors (one for dampner) and many velocity layers, in a mix.

Finally, Dan - what about Gary's question of keyboard zoning - I'm not clear on how that affects polyphony - can you provide any extra clarity on that (I accept you pointed to the manual already !!). for example - if you zone a bass sound in a program to the lower two octaves only and play a note in a higher octave - are voices played /used up?

Thanks,
Kevin.

[danatkorg]

I get the feeling that we may be missing some basics here.

There are two main types of resources:
* stuff that uses CPU power as soon as you select it
* stuff that only uses CPU power when you play notes

The first category, "stuff that uses CPU power as soon as you select it," is comprised of:
* effects
* EXi fixed resources

For more on EXi fixed resources, the manual citations above should be helpful.

Everything else in the system - everything to do with the HD-1, for instance - falls into the second category: "stuff that only uses CPU power when you play notes."

The number of velocity zones in a Program or Combi does not affect polyphony. Neither does the number or range of keyboard zones.

The only question is how many voices are played at a time. If velocity or keyboard zones overlap, either as layers or as crossfades, then the stuff in all overlapping zones plays at the same time. More voices play, and so more processing power is required.

[ldascanio]

You have two other options when designing a COMBI that could be useful to minimize polyphony issues:
1) Look in your manual the TIMBRE PRIORITY parameter.
With your Oasys in COMBI Mode go to the tab TIMBRE PARAMETER > MIDI
You will find in that screen the TIMBRE PRIORITY parameter. if you select the most important timbre as Priority then the Oasys will take notes from the other timbres when reach the polyphony limit preserving the ones for the timbre set as Priority. This doesn't give you more polyphony but perception is totally different as the notes stolen are taken first from the less important timbres in your combi.

2) ENABLE DAMPER parameter:
If you are using a Damper pedal you can select this parameter only for the tiembres that really need it or are very dependant on playing style as the Piano. Remember that sounds that are hold with the damper pedal keep using notes even if the sound disapear quickly and polyphony is recovered only when the pedal is released.

Rgds.
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