Questions about EFL, SVF, WS module and MIDI

I have some question about the EFL, SWF, WS module and MIDI.

  1. In EFL, what is the meaning of negative threshold value? Is it mean that the negative side of the signal? (-5v to 0v).

  2. In SVF module, is “PK” mean peak filter?

  3. In WS module, what is “W/D” parameter mean?

  4. Can I use the right USB port to receive midi signal from my DAW? If not, are there any other ways to receive midi signal from DAW? Or can I use USB-A to USB-A cable to plug in the middle USB port?

Thanks so much!

I’ll have to check 1-3…

  1. does it do anything? or perhaps a UI anomaly
  2. W/D - wet dry?

no, and no …

indeed the correct way to sent midi from a DAW would be to use the right most port aka usb device port.
however, the SSP currently does not support USB midi device (only usb midi host) , rather it this as for USB audio. SO… rather than midi you could send CV over usb audio if your daw supports (e.g. bitwig/ableton both do!)

the USB A ports are for USB midi host (like a computer) so you should not use a USB A to A cable… (these should be banned :wink: ) , as this would be connecting a usb host to usb host which is invalid.

however, there are a few solutions…

use a USB -> MIDI DIN cable, these can be very cheap …
if you don’t already have midi din available on your computer then, you’ll need two.


(there are much cheaper versions than this roland one)

another option i’ve used is a usb host to host adapter.
https://sevillasoft.com/index.php/midi_usb-usb/

finally, a few usb ‘hubs’ which support multiple hosts.
e.g. https://www.iconnectivity.com/products/midi/mio2

overall, if you don’t a midi solution - I’d try the cv over usb … its a fun option to use and explore anyway,
even if you come back to midi afterwards :slight_smile:

Thanks for the information about midi and W/D is wet dry in WS module.

For EFL module, I’m not sure the reaction.

Also, may I ask one more question about the SDL module, why the modulation input for delay seems no respond?

SVF - PK is Peak Filter. By the sounds of it, the Peak Filter has a wider bandwidth than the Band Pass Filter (BP). So if you want to narrow in on a frequency band, the BP is your best bet and vice versa.

SDL - The SDL exhibits an unusual behaviour in that when you modulate the length parameter, the delay clears its buffer first, before outputting the Delay signal again. If you use something like a slow LFO to modulate the delay time, e.g. to create a chorus effect, you end up with nothing. The Delay length is being modulated continuously therefore its buffer is being cleared continuously and nothing audible seems to happen. You experience the same effect when changing the feedback directly too - it takes a while for the updated setting to kick in. This has been discussed on the forum before and bert has promised to look into it. In its current incarnation the SDL is a very nice set and forget delay. I use it to create bubbling background repeats with relatively high feedback values. It can have a nice tape-ish character that way. Don’t forget to explore the Drive setting which can have a hugh influence on the sound character - it is in essence an overdrive circuit on the delay input.

Oh, I see. But even if I modulate the length will a constant cv (e.g. using DCG), seems no effect. Is it mean that the modulation input of length is useless?

This sounds harsh. I’ll put it more mildly as that there is currently no practical use of modulating the delay length in the SDL module other than using it as a mute-function.
As I said, the SDL can be a very nice addition to a patch as long as you configure once and leave it as-is while you modulate other elements.

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I think I must be having a ‘bad day’ :frowning:

as far as i can see @yhiitming is correct,

SDL: Dly does not seem to work at all… connect a DCG to it, and it doesn’t do anything.
in fact, it also stops the Dly on the UI doing anything either.
(you would expect delay time to be SDL:Dly + SDL:Dly CV)

test case:
INP->SDL:In->OUT out1/2
DCG-> SDL:Dly
(ensure inputs active as relevant)

set SDL:Dly short, and then try different values in DCG:1…
expected result: DCG alter delay time
actual result : i always got same delay time,
checking cv scope on SDL:Dly showed signal correctly from DCG

@bert perhaps you could take a look? throw some light on this

edited… thanks to @yhiitming, discovered threshold only applies to gate, not env output.


similarly, as far as i can tell EFL:Thr1 is not doing anything for me…
i get an envelope output that is proportional to the input signal, but is fired regardless of what level the threshold is… i.e. id expect Thr1=1.0 to mean only the loudest signals will generate an envelop - but still very quiet signals get thru.
test case
LFO:sn -> OUT 1/2
INP:1 -> EFL:in1
EFL:out 1-> LFO: amp
(ensure inputs enabled as required)
feed different signals into IN:1 you will hear LFO follow its envelope ( i used a plucky sounds for testing)… now alter the threshold …
expected result: threshold should mean envelope is not triggered unless audio is above a certain threshold level.
actually result: as far, as i could see it made no different at all, even making IN1 very quiet, i still got an envelop regardless of threshold level

as for -ve threshold… Id assumed/hope it would generate an inverse envelope… but for sure it’s a little unclear.

I think the threshold of the EFL is to trigger the gate output signal. When the input signal exceed the threshold, EFL will trigger a gate output signal. But it seems that it will trigger multiple gate signal which are very fast (e.g. 1 kick drum trigger many gate signal) , because of the input signal crossing above and below the threshold very fast.

doh, yeah… didn’t see the gate output … makes sense that threshold is for gate.

-ve values seem to be treated similar to +ve, so -0.6 seems same/similar to 0.6

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