Use the "Unit Multiply" parameter.

To use "Unit Multiply", you would set Sync to Tempo. And then your tempo becomes a reference clock multiplied (or divided) by the unit multiply setting.

Unit "Multiply" is interpreted as what percentage vs. the base tempo TIME is multiplied by (not tempo, time). A 100% Unit Multiply is setting time times one (x1) -- which is just the tempo as-is. When Unit Multiply is larger than 100% then we are increasing the amount of time the resulting phrase takes to complete. So 6400% (the maximum) means take 64x more time than would otherwise this phrase would take to complete using the reference tempo.

As you should know, when Sync is OFF and you setup a fixed "Speed" - the speed is not related to tempo at all. So a speed of 1 will run just as fast (or slow) no matter what your tempo is.

Since setting the Sync to "Tempo" involves the tempo - you can also lengthen the amount of time a fade takes by decreasing the tempo.

Say your tempo is 120 bpm. You may not have anything else that is tempo referenced (like arpeggios or other motion sequences that set Sync to "Tempo" in other Parts). In this case, there's no harm in just adjusting the tempo to whatever would help you reach the "fade time" you're after.

Now, if you do have other arpeggios or motion sequences which vary with tempo - you can take your tempo of 120 bpm and say set it to 60bpm instead. This will provide a much slower tempo for your motion sequence used for the fade. You can unit multiply this by up to 6400% which will provide the slowest fade (most amount of time). Now - once you do this your other arpeggios and motion sequences that are referencing tempo will be 2x slower too. This isn't what you want, so go into those arpeggios and motion sequences and change their Unit Multiply to 50%. This means make those take 50% less time than using the new reference tempo. This will make these other arpeggios and motion sequences run at the same speed as when your tempo was set to 120bpm.

[quotePost id=118591]
I get a fade out of about 20 seconds using a speed of 1.
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Nice one, I'd like to ! Mine is 12-13 seconds, 20 seconds would be nice.

[quotePost id=118591]
1. What kind of sound are you fading? piano, strings, brass

2. Are you holding down the keys until the end of the fade out or are you wanting the fade out to occur only after you release the keys?
[/quotePost]
I use an electric piano and a kind of synth pad.
Keys are not hold down, I play a melody that I'd like to be fade out.

Using Unit Multiply
You can use Motion Sequences to create a fade (maximum of 8 MSeq can be simultaneously active in a Performance) and since your synth can count measures and beats you can fashion a fade out of any musical length you require.

The Motion Sequencer: Automated Value Change using Musical Sub-Divisions
The Motion Sequencer can run on its own (Speed), independent of the synthesizer’s main tempo or you can synchronize it to other functions within the synth (Sync to Tempo). When you want to synchronize the parameter value changes such that they occur at specific locations within your music, this is possible.

The Motion Sequencer allows you to create a map of value changes using as many as 16 Steps. The Steps are simply reference points - you can choose to use them to place a ‘value’ - naturally this will depend on what you need to accomplish. To accomplish a fade out you might want to create a Motion Seq, whose values change from minimum-to-maximum across several the Steps in your Cycle. Use the EDIT SEQUENCE function to construct a 16 Step MSeq where each successive Step is a higher value. Start at 0 and finish at 127 Step 16.

Ex. Use the “HOLD” preset (pulse shape) and fashion your Seq so it looks like a staircase going up… each successive step a few increment higher from left-to-right.

Each Step can represent a specific parameter value — the distance between points is an interpolation of value change. You can ‘smooth’ the leap between Steps or make it jump from point to point. You can use this shape to increase or decrease the associated parameter value; you will apply the direction when you go to Part Assign and address the parameter (Part VOLUME) within each Part you wish to fade. (Create a USER Motion Sequence because you may want to apply this to other active Parts in your KBD CTRL program (8 Parts maximum).

Since Motion Sequences are always started by an event - either by striking a Key (at the appropriate location and/or velocity) or via pressing the dedicated [Motion Sequence Trigger] button or by having an Arp Phrase initiate it.

For example: If you create a Motion Sequence with Cycle = 16 Steps, with “Tempo Sync” active, and “Unit Multiply” = 100%, each time through a Cycle is one measure at the current Performance Tempo... making each step a sixteenth note (assuming 4/4 time). But if you were to change “Unit Multiply” = 6400%, the Motion Sequence Cycle will not complete its run for 64 measures, calculated at the referenced Tempo. And each Cycle Step is 4 measures apart!

You can adjust the number of Cycle Steps and the Unit Multiply to suit your needs. This is actually very flexible and is worth your time to gain an understanding about how it works. A Unit Multiply of 200% along with Cycle = 8 is very much the same as a 16-Step Cycle at 100%; which is also the same as 400% Unit Multiply with a 4-Step Cycle.

Use the number of Steps in your Cycle along with the Unit Multiply to create the precise length fade that you require.

Use the Control Assign screen to apply and shape the application of this MSeq. In a fade out scenario, a negative RATIO value will reduce the parameter value (direction). The PARAM 1 shapes the Curve. The higher the Param1 number, the later the fade occurs. Each Part can be set to fade a differing rates, if you desire.

Use the RATIO setting to determine how deep the fade. You do not have to fade to 0 volume, you can if you wish… just adjust the negative Ratio value to set the final setting (silence).

A Motion Sequence is a map of value changes
Create your ‘value change’ map to suit your musical needs.
Say you want to fade out to silence 8 measures after triggering the [MOTION SEQ TRIGGER] button.
Set the Unit Multiply = 800%
Cycle = 16 Steps
Now each Step of your Cycle is equal to a half note
When Cycle = 16 Steps that is precisely 8-Measures from beginning to end.

Set Loop = Off to make this a one-shot (good for a fade out).

If you need an example, let me know.

Extra Credit: Since this Motion Sequence will fade each Part Volume separately to silence, to reinstate them to their original Part Volumes simply reset the Motion Sequence by toggling the Master Motion Seq On/Off button.

[quotePost id=118603]
The PARAM 1 shapes the Curve. The higher the Param1 number, the later the fade occurs. Each Part can be set to fade a differing rates, if you desire.

Use the “HOLD” preset (pulse shape) and fashion your Seq so it looks like a staircase going up… each successive step a few increment higher from left-to-right.
.[/quotePost]

Twisting the curve with parameter 1 set to 8 is really satisfactory, I'll keep that one.

Tested the staircase trick, probably the best solution for extra long effects but needs fine tuning.

Many many thanks ????

Romuald

Tested the staircase trick, probably the best solution for extra long effects but needs fine tuning.

Just some background on fading out…
In general, by the time a musical program has dropped a certain amount in volume (approx. -9dB) the average person stops paying attention and their brain detaches from that music program as their attention returns to their immediate (non-musical) environment. They will lose interest in the music and will assume it is going to disappear completely, very shortly.

Certainly, on radio, you very rarely hear the complete fade of a song… (it’s the greatest fear of radio folks… silence. Down -9dB is as close to silence as they ever want to get).

This is why a slow fade, one that begins gradually and then becomes more severe and rapid as it goes, seems to work best in most situations. (Similar to a negative Ratio, Param1 = greater than 5).

A linear fade (5) reaches the “lost interest” point, way too fast.
Also no one fade works for all music programs — it is very program specific.
Only musicians listen all the way to end, trust me, civilians enjoy music, musician’s live the music (no one listens as close as musicians — or those who have one trapped inside)

Use the “Edit Sequence” > “Amplitude” and “Smooth” parameters to make further adjustments to your Motion Sequences value map. “Smooth” will turn the staircase into a slide. Instead of a new value at each Step, it will serve to interpolate the difference between Steps to, literally, smooth the changes.

I'm a little surprised Reverb hasn't been mentioned.

Reverb creates, I think, the best fade outs.

On musical interleavings with fadeouts, that are long, cinema is one area this is done a lot, often keeping it going long enough to provoke little foretelling bits suggestively.

In games, between menu transitions ideally do long fades, too.

Have a look at stacking Gated Reverbs Effects (one in the part, one in the Common Effects) to get hugely long reverbs that can be smeared such that they don't alias annoyingly.

[quotePost id=118671]

I'm a little surprised Reverb hasn't been mentioned.

I don't see how Reverb is relevant to a question about Fade Out.

Reverb neither increases nor decreases the level of the sound. It combines a sound stream with a delayed version of the same stream. It doesn't adjust the volume.

Reverb creates, I think, the best fade outs.

Can you provide an example of the Modx doing that using only Reverb?
[/quotePost]

You've described delay.

Reverb caches the sound stream and simulates bouncing it around within a space, fading as the supposed surfaces absorb and sounds escape the area. Gated Reverb operates only on a space, not time like the others, so it's possible to create hugely long reverbs with it, when using a lot of feedback (up near 63 or down near -64 in Yamaha value ranges).

It'll alias by itself at most settings, so it's best smeared somehow afterwards, either with a smeary chorus or another, shorter reverb.

Because these are effects, that are controllable in terms of wetness, feedback and other attributes, over time, the fadeout (which is largely automatic with a reverb) can be wonderfully tailored, in infinite ways. It's not merely a volume fade, it's the dissipation of simulated sound energies.