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Hi again,

With some calculations I relised that dotted is in fact the 1.5*the straight value... easypeasy

But, a new question arises, how to build a hipass-rising feedback in a delay in Modular2? Not something that just filters the feedback through a hipass, but something that gradually filters each bounce... like an infinite multitap. But there´s no multitap in the Modular2, no?

M

Hi Massus,

Maybe I don't understand your question correctly, but isn't a hipass filter in your feedback path exactly what you want?

The effect of the hipass filter would be that your feedback signal will gradually lose all it's lower frequencies and if your feedback level is high enough, nothing is left eventually.

I think 1 or 2 pole (6dB or 12dB) filters work best, because their slope isn't steep. This will give the hipass-rising you're looking for, I think.

cheers,
vincent

Hey,

What you want to do is split your signal into dry and wet. Dry is untouched throughout the patch. Wet is sent through a delay unit (which is set to 100% wet). Add any effects or filters you want before before you mix the ouput of the delay back with the input signal (through the xmod/feedback module).

Hi,

Maybe I´m complicating things, but to get each bounce in the feedbackloop to get filtered more- without affecting new bounces just going into the feedbackloop- you must separate he bounces using a multitap- or? I mean, if not you affect the whole feedbackloop as soon as you tweak the cutoff.

Hi,

That's right, I think you're complicating things

I think you shouldn't need to tweak the cutoff frequency to get the results you want. Everytime a bounce passes the filter, the bounce will get filtered more.

I'll try to visualize it. A lowpass filter with a slope like the one below wouldn't give you the result you want, because the first time a bounce passes this filter all the signal frequencies above the cutoff frequency are lost and all the signal frequencies beneath the cutoff frequency are unaffected:



Passing a bounce again through this filter wouldn't change the sound anymore and you indeed would have to change the cutoff frequency over time to get the result you want, but with the unwanted side effect that all the bounces will get affected.

Fortunately, filter slopes look in practice more like this:





When a bounce passes this filter, not all the signal fequencies above the cutoff filter will be lost. If the above filter would be a 6dB/octave lowpass filter with a cutoff frequency of 1000Hz, the audible content of this bounce at 2000Hz will be dampened by 6dB, 12dB at 3000Hz, 18dB at 4000Hz, etc. If the bounce passes this filter the second time, the audible content of the bounce at 2000Hz will be dampened by another 6dB and at 3000Hz another 12dB, etc.
The result is that it sounds as if you would turn the cutoff frequency down over time per bounce.If you would use a hipass filter, the result would be the oposite. How steeper the filter slope (For example, a 12dB/octave filter instead of a 6dB/octave filter, how faster the sound will change.

To conclude this long story: Just start experimenting with different filter types and different cutoff frequencies. I'm sure you'll find the result you're looking for.

cheers,
vincent

edit: visualizing the filter slopes with asci characters wasn't a good idea, so I replaced them with ugly pictures

<font size=-1>[ This Message was edited by: visilia on 2002-08-05 09:51 ]</font>

Not in Mod2, but can be used in an insert rack:



Visit http://www.neutron7.com for more info on the device...

Oh Yeah! That's one of my favourite Neutron devices. A little tip to get some weird but beautiful sounds out of it:

Put a chorus or something similar (I've used Hexachorus) in the feedback chain, Set the feedback of the Retron at a high level and just use the Analog inputs of your Pulsar/Scope/Luna as input in Retron (Just to feed the Retron with a little bit of noise).

Now start playing with the Hexachorus and Retron controls and before you know it's a few hours later (But watch out for unwanted feedback noises due to too high feedback levels)

cheers,
vincent

Thanks Visilia,

you were right, the filter indeed didn´t need to be swept. Great! And thanks atomic, great little device!

M