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Reface dx feedback question
Old 16th January 2018 | Show parent
  #31
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Quote:
Originally Posted by souljahh View Post
care to elaborate? Maybe the "pow2" is not what i'm getting and makes this patent not clear to me. Tnx
8 squared = 64
Or 8 to power of 2
English is not my native language .
Old 16th January 2018 | Show parent
  #32
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Quote:
Originally Posted by acreil View Post
I think it's actually absolute value. If you use absolute value, you can vary the foldover point and get PWM-like effects.

What would make the most sense is to add a second feedback envelope so that the operator amplitude and waveform can be controlled independently.
Acreil , at least some one who knows what he's talking about , instead of all the rest ..criticizing without having a clue

Yes , either absolute value of pow^2 gives a square wave , slightly different .
Imgur: The magic of the Internet

A picture says a thousand words .
Notice the slight differences in square shapes
Old 16th January 2018 | Show parent
  #33
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Quote:
Originally Posted by souljahh View Post
care to elaborate? Maybe the "pow2" is not what i'm getting and makes this patent not clear to me. Tnx
When the feedback is powered ( or rectified ..gives a slight difference ) ,the output of the operator is square wave .
That'w what yamaha patented on their reface dx ..you can vary the modulator's output between a rectified ( square ) and non rectified ( saw ) .

I started this thread because I wanted to know if feedback ( and added rectification) took place pre or post envelope ...which makes a difference , because post would mean that the actual envelope controls the gain going back to the operator(feedback ) and thus gives us control over the feedback amount .
Then some random guy start to criticize/facepalming because I pointed this out (pretty sure he doesn' t have a clue what I am talking about ..but for some reason he wanted to be heard )
As a defence I pointed them towards a reaktor ensemble I've made that was capable of continous variable feedback square/saw ..
The only reaction was some facepalming .
Here's an audio example of variable operator feedback ...square--->sine---->saw--->
IN the last part the amplitude envelope controls feedback ( as on the original dx ) thus going from saw-----sine
square---->sine ( square -->sine not possible on dx synths , since there is no rectification going on )
https://app.box.com/s/a3wuueomf5bix3a6imz8dh23ctfvpkge
Old 16th January 2018
  #34
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🎧 10 years
Quote:
Originally Posted by gentleclockdivid View Post

If the new feedback per operator is the only feedback system possible , we can't do this .
this is completely false and shows how much your knowledge of FM Synthesis is lacking: the only systematic difference between one sinewave modulating itself and modulating another sinewave is that the latter gives you a) the ability to modulate the amount of modulation b) choose individual frequencies for both "Operators".

If you want to change a sinewave into another waveform (say a saw-wave) over time using FM-synthesis, you modulate it with another" Operator"and modulate the amount of this modulation (e.g. by velocity and/or an evelope and/or an LFO) - as simple as that.
Old 16th January 2018 | Show parent
  #35
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Quote:
Originally Posted by gentleclockdivid View Post
.
This is called POST ENVELOPE FEEDBACK , and al original dx synths have them ...you can go from saw to sine with just one operator set to feedback .


"post envelope feedback" - Google Search
Old 16th January 2018 | Show parent
  #36
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Dude , I give you a link to my ensemble??have a look inside .

Some facts .
A sine wave , phase modulating itself = feedback .= saw wave
Each operator has an amp.evelope .
Fact ..the amplitude envelope controls the amount of gain output and thus ALSO the amount of feedback going back to itself .
I posted a screenshot on the first page .

Post envelope feedback MEANS , that the gain multiplier is POST envelope ..
In other words envelope multiplies gain ...from there on it goes to the output and back to the operator ( if feedback enabled ) .

On the reface , the feedback is PRE-envelope , meaning that the envelope has NO effect on output that is routed back to the operator .
DO you understand .


I hope you do this simple test to see for yourself and stop trolling .
Load dexed vst ..choose algoritm 32 where the last operator has feedback and is routed directly to he output
Enable this operator and only this operator .
Set feedback to full and set envelope to a long decay and no sutain .
Record audio
Result is saw ----sine and ofcourse a decrease in volume .
Conclusion ..the envelope controls feedback and is thus .post envelope feedback .
All of this written above can be checked and double checked by oher people


Give it a rest ...you're obvously trolling and or to stupid to comprehend .
Old 16th January 2018 | Show parent
  #37
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Quote:
Originally Posted by Jens L. View Post
this is completely false and shows how much your knowledge of FM Synthesis is lacking: the only systematic difference between one sinewave modulating itself and modulating another sinewave is that the latter gives you a) the ability to modulate the amount of modulation b) choose individual frequencies for both "Operators".

If you want to change a sinewave into another waveform (say a saw-wave) over time using FM-synthesis, you modulate it with another" Operator"and modulate the amount of this modulation (e.g. by velocity and/or an evelope and/or an LFO) - as simple as that.
This proves you have never even touched a fm synth .

One operator feedback =s aw

I do it on my nord and every other phase mod. synth that is capable of that .
Old 16th January 2018 | Show parent
  #38
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Did you try what I have said ?
Load dexed synth , and choose algo 32 , set feedback to almost full and a long decaying envelope.( no sustain )
Only operator 6 enabled

Put an osciloscope on your master ..it might convice you you were wrong .


Come back later .
Old 16th January 2018 | Show parent
  #39
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https://app.box.com/s/lvmly9gco740zon832eakuvu6qs1xw8v
Difference between pre and post envelope feedback + soudfiles
Imgur: The magic of the Internet
Pre envelope = left channel
Post envelope = right channel

Both channels obviously decrease in volume ,but onnly the right channel goes from saw to sine ..becaus the feedback amount is also decreasing .
The left channel only decreases in gain , the added harmonics stay the same (remember self feedback= saw) that is because it's feedback amount is static ( pre envelope ) and thus not affected .

I think I gave enough proof , now it's your turn
Old 16th January 2018 | Show parent
  #40
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Quote:
Originally Posted by gentleclockdivid View Post

I think I gave enough proof , now it's your turn
Proof for what? What do you think we are arguing?

I did not even mention Dexed.


I'm inclined to believe we are witnessing the results of severe substance abuse here.
Old 16th January 2018
  #41
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Sorry to be ot,

But how does the reface method change the normal dx7 results?

Is it literally a limitation or can you just get different results? (Also any other changes that might be there)

Can you not load dx7 patches then?


I love dexed, but would also like a different flavour if it was good
Old 17th January 2018 | Show parent
  #42
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The feedback on the reface is static (not modulateable)
and is not affected by the operator's envelope .
I coined the term pre-envelope ., it's a separate feedback routing that multiplies the output of the operator back into itself but not multiplied ( gain staged ) by the actual operator envelope .
It is a big difference.
Old 17th January 2018 | Show parent
  #43
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Quote:
Originally Posted by Jens L. View Post
Proof for what? What do you think we are arguing?

I did not even mention Dexed.


I'm inclined to believe we are witnessing the results of severe substance abuse here.

To debunk what I have written .
I mention dexed , so you can see and hear for yourself ...and to prove that the original feedback algo is post envelope .


You're on my ignore list ..big mouth but no brains to back up his claims
Hold on to your ego
Old 17th January 2018 | Show parent
  #44
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🎧 10 years
Quote:
Originally Posted by rasseru View Post
Sorry to be ot,

But how does the reface method change the normal dx7 results?

Is it literally a limitation or can you just get different results? (Also any other changes that might be there)

It is not off topic at all. I think the Reface DX is the best FM Synth there is.

It can not load DX7 patches but it is very powerful in ist own right.

There are things the DX7 can do which the Reface can't and there are things the Reface can do which the DX7 can't.

The Reface however is very easy to grasp and program - which is part of what makes it so great.

Every one of the four Operators of the Reface can have feedback, which goes in increments of 1 from -127 (they call that "negative feedback") to 127, which slowly goes from a squarewave to a pure Sinewave (0) to a sawwave. So without being modulated by another operator, each of these four Operators can already have one amongst a broad range of different waveforms.

The DX7 has six Operators, but all - except one - are pure sinewaves. Therefor they need to be modulated by other modulators in order to carry different waveforms.

With each algorithm one of the modulators can have feedback with a value from 1 to 7 (i.e. it is eight possible different waveforms in total, including the pure sinewave - no negative feedback and it is static too).

The DX7 has 32 different algorithms, the Reface 12 (which also makes it easier to choose an appropriate one).


The Reface sounds really fantastic btw. - I wouldn't ever want to part with it.

Last edited by Jens L.; 17th January 2018 at 01:28 AM..
Old 17th January 2018 | Show parent
  #45
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You just summed up the reface dx specifications , you're a real genius .

Do you know how that square wave is achieved ?
Well then , read trough the first page , it's all explained .
If you can fathom that , have a look at the differences between pre / post feedback ....I know you don't like that word ...but hey ..it's make life's easier to give it a name .
It's all explained on this page ...with pictures and sound files ...
Then when you're starting to comprehend it all , you might come to the conclusion you're were behaving like a litlle kid , with absolutely no constructive arguments and back up
Old 17th January 2018 | Show parent
  #46
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Quote:
Originally Posted by Jens L. View Post
The facepalming was just because you are seemingly a very confused individual, barely know what you are talking about and obviously lack the ability to be logically cohesive, even in a thread you started yourself.

The amount of nonsense you delivered here is mind-boggling.
Could you please elaborate on this .
What do you think I have said/written is wrong or are lies .

Pre /post envelope feed back ?
- That one is explained above .
Anything else ?

How to achieve a square wave ?
That's explained ..by routing the squared ( to the power of 2 ) or rectified signal ( pointed out by acreil) back to itself
Examples and screenshots are also given ..

I hate to be falsely accused of lies ..that's all
Old 17th January 2018 | Show parent
  #47
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🎧 10 years
Quote:
Originally Posted by Jens L. View Post
<Deleted by Moderator>
POint out where I am wrong , and show what is not correct .
Or just admit you didn't have a clue about it .
You' re really a pathetic troll .
The evidence is right in front of you , yet you keep looking the other way .
https://app.box.com/s/lvmly9gco740zon832eakuvu6qs1xw8v
Prove this is wrong or just shut up


Last edited by gentleclockdivid; 17th January 2018 at 07:01 PM.. Reason: Bickering
Old 17th January 2018
  #48
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Does it do anything different on the twangy plucked sound?

It's one of the things I love about the dx7 - old deep techno sound with plucks that cut above my analogue basses

Or is that not affected
Old 17th January 2018 | Show parent
  #49
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Troll.
Do you know what an envelope is , and what it multiplies ?
Yes it multiplies an a.c. signal ( audio) with a d.C signal ( direct current )which is the envelope .
We call this amplitude modulation .
Every operator in the dx series has that .
We agree on that
NOw ..feedback .
Signal going back to the operator .

On the orignal dx series , there was only 1 operator per algoritm that was capable of feedback .
Agree ?
Sometimes this feedback enabled operator was a modulator , and in some algoritms it is a carrier , straight to the ouput.
Soloing an operator with self feedback directly to the output gives a saw .
You don't have to agree , but it's a fact ..and the examples are given .
The reface takes this to higher level , every operator is feedback enabled .yamaha called this positive and negative feedback .
When the feedback signal changes polarity , it just becomes an upward saw ..
Yamaha choose this term' negative feedback ' just not to confuse people .
In fact ...the square wave is achieved by rectifying the feedback signal ( rectifie means absolute value )
It's a nice added bonus , because you don't need other operators to add harmonics , you can do it with just one .
Good .
NOw ....let's get back to our envelope .

The gain output of the operator is multiplied by it's envelope .
This envelope reduces the gain ( tada ) of the signal , it is that signal that on the origingal dx series is also routed back to itself when feedback is enabled ( see screenshots and audio above )
And I am pretty sure that's the part that you don't want to understand , because I called it post envelope feedback .

Take your reface , dial in full feedback ( saw ) and apply a decaying envelope ( no modulators , just a parallel algoritm )
The result will remain a saw wave , the operator retains all it's full harmonics ..none are taken away ..
I call this 'pre envelope' feedback ..because the feedback block is not altered by the envelope , the gain reduction of the output signal ( shaped by our envelope ) is not a part of the feedback diagram
The feedback loop is happening before the envelope output stage

Do this on any other dx synth , again one single feedback operator directly to output , the result will be a saw wave that will lose harmonics ..because the decaying envelope is providing LESS gain in the feedback loop
You might want to read the above sentence again , because it is crucial ..I highlighted the important words for you .

This is the last time I have taken the effort to explain this to you , just to be absolutely sure you're either confused or a troll

Last edited by gentleclockdivid; 17th January 2018 at 03:55 AM..
Old 17th January 2018
  #50
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@ gentleclockdivid

Save your strength, friend. Use the ignore button if you must.
Old 17th January 2018
  #51
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Yeah , don't spend time arguing with idiots ..you know the rest ..the guy has some serious issues ..probably didn't get enough attention ..
Anyway , here's an ensemble I made in reakor , like the reface it has 4 operators capable of square/saw feedback and POST envelope
Ten partials for each opertor .
You can get it here
Mono Fm | Entry | Reaktor User Library

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