Working on a sequence tremolo

[Galego]

http://www.youtube.com/watch?v=H31XsuynMOI

Please let me know what you think. I think i'm going to call it "HTU Tremolo" (hard to use). 

Any suggestions would be highly appreciated. 

[Gurner]

Very nice.

Could you point me to the switch/pots you are using....they're right up my street.

I'm presuming this is using a PIC?

What are you using to control the signal level (a digipot?)

[Galego]

I'm using these rotary encoders (with switch):

http://pt.mouser.com/Search/ProductDetail.aspx?R=EN11-HSM1BF20virtualkey57700000virtualkey858-EN11-HSM1BF20

Yes, it's a PIC2550, and i'm using the PWM output and a Vactrol to control the signal level, just like a tremulus lune.

[Hides-His-Eyes]

Impressive stuff!

[petemoore]

  Reminds me of the 'ol T-Bird turnsignal lamps !
  Very cool how these breadboards can work up circuits.

[~arph]

Very cool!

Although it will make things a bit more complicated, I'd like to see envelope controlled speed or depth. Or soething like a ramp up/down switch for slowing down and speeding up the rate.

Regards,

Arnoud

[jasperoosthoek]

Very original idea, I love it!

Maybe you could have a rotary encoder for every red LED. When you turn it it automatically switches the green volume LEDs to the one you turned. That'll make it a lot easier to use I guess.

[defaced]

Dood, that's cool.  I'd build one.  To have rhythmic trem like that would be really cool. 

[Galego]

Very cool!

Although it will make things a bit more complicated, I'd like to see envelope controlled speed or depth. Or soething like a ramp up/down switch for slowing down and speeding up the rate.

Regards,

Arnoud

I've been thinking about doing a tap tempo detection from the guitar, you would strum the tempo, i don't think it would be that difficult... And picking notes harder or softer to set the steps would really be interesting, hmm...

Very original idea, I love it!

Maybe you could have a rotary encoder for every red LED. When you turn it it automatically switches the green volume LEDs to the one you turned. That'll make it a lot easier to use I guess.

A rotary encoder for every led would be very expensive, and i would need more PIC's. This is a 28pin PIC and i ran out of in/outputs. Each rotary encoder uses 2 pins and one more for the switch. In a non audio circuit i would do port multiplexing, that's what i started with, it worked but the led switching would bleed horribly into the audio signal. I'll probably try this with a 40 pin PIC 18F4550, just to complete the 8 leds for the second knob, and maybe to add tap tempo.

[Galego]

http://www.youtube.com/watch?v=3E3PCA-tY-I

Please give me some criticism

[Taylor]

Of course, there's no requirement that you post your schematic or code on this forum. But without that, what criticism can anyone here give?

If you're just looking for comments from a consumer standpoint, TGP or another consumer forum would seem to be a more appropriate place for this.

[Galego]

I can post the schematics, not that they're that useful, it's just a tremulus lune without the LFO. The rest is PIC driven, so it's all in the software.
I'll post them later.

But i don't see why people here wouldn't be able to criticize an effect from a user point of view... Aren't we all builders and users?

[jasperoosthoek]

Nice that got it in pedal form. I really like the concept. The LEDs are slick. Only two knobs .

[petemoore]

 OK you asked for it;
 Devils advocate here...
 Simple trem design with a few waveforms and very simple algorythm seems to suit me...probably because that's what I'm used to..cycling repitition.
 Could be when I expect an 'off' attack an association with note change is expected, or could be that when I hear the 'off' attack in a sequence I listen for it to repeat, when the repeat doesn't fit an algorythm I feel my algo-searches were in a complicated joke with no punch line...I had to think about it in some depth and could make no sense of it feeling.  
 The control potential though does look substantial, perhaps some 'treble/bass' or non-linear-waveform behaviour thrown into linear sweep algorythms, something to set one 'lump' of volume apart from say..the other three.
  Another might be a tone sweep before the trem, something with sweep before trem makes a 'strobe light' effect, marking 'positions' as the sweep moves slower than the trem LFO.
  Besides the luxurious distractions which are deserving of admirations upon inspections...ie the pedal looks great and real attention-keeper with the LED/controlled light/ sound thing going on, nice finish !
  And a very interesting experiment, I've never heard anything quite like it, makes wonderful tremolo effects by the way.
  I have a Lune, and twisting the knobs is a user-knowledge base test as well as a bit of doing to get from 'this trem' to a different one I think is 'optimal' [ie downramp to sine for instance], I was once about to simplify somehow the controls into say 3 optimized trem-tones, but couldn't do it, every once in a while a 'trem-fanatic' becomes entheused enough to twiddle and ask about knob interfaces for 10 minutes.
  Most of my trem I actually end up using involves the nice trem-sound I already have on an amp knob [or footswitch].

[~arph]

A rotary encoder for every led would be very expensive, and i would need more PIC's. This is a 28pin PIC and i ran out of in/outputs. Each rotary encoder uses 2 pins and one more for the switch. In a non audio circuit i would do port multiplexing, that's what i started with, it worked but the led switching would bleed horribly into the audio signal. I'll probably try this with a 40 pin PIC 18F4550, just to complete the 8 leds for the second knob, and maybe to add tap tempo.

Very nice! I like how you placed the LED's. It looks a bit complicated to set up though, with only two knobs. You could of course use two SIPO shift registers to set the led's and that would only cost you tree i/o lines. It does require some extra ic's.

[gtudoran]

Good Job both of you ... nice little thingys love them

Best regards,
Gabriel Tudoran
Analog Sound

[Galego]

Very nice! I like how you placed the LED's. It looks a bit complicated to set up though, with only two knobs. You could of course use two SIPO shift registers to set the led's and that would only cost you tree i/o lines. It does require some extra ic's.

Yeah, but i really wanted to be able to fit it inside a small enclosure. When i take it apart i'll take a picture, it has two boards, the rotary encoders and leds are on a daughter board, i don't know if i could fit those ICs in there... I think the most user-friendly option would have been an LCD display, but i think it somehow ruins the look of guitar pedals. I wanted to keep it as simple as possible, and it's not that bad to use once you get used to it.

Next thing i'm going to do is to do another circuit where i replace the tremolo part of the circuit (the op-amp) with a colorsound inductorless wah and do a wah version.

I think i should explain what it does now:
It has 3 modes that are cycled through by pressing on the left knob.
Mode 1
- Rotating the left knob lets you select the number of steps.
- Rotating the right knob controls the speed
- Pressing the right knob generates random depths for all 8 steps, keep pressing until you like one.

Mode 2
- Rotating the left knob lets you select each of the 8 steps.
- Rotating the right knob lets you define the depth for the step selected by the left knob
- Pressing the right knob inverts the waveform, not very useful.

Mode 3
- Left knob is only used in the Load/Save positions of the right knob, to select the bank (1-8)
- Rotating the right knob lets you choose the waveform and load/save presets. Each position does the following:
  1 - ramp up
  2 - ramp down
  3 - sine wave
  4 - triangle
  5 - square
  6 - Load
  7 - Save
- Pressing the right knob executes each of the previous actions.

[deadastronaut]

love it....brilliant..

i like an led or 2 or 20 too......nice man...

[Galego]

I've made basically the same pedal, but instead of a tremolo, it's a wah. I used the colorsound wah circuit and the rest is exactly the same.




I'm going to have to clean up the schematics and code before i post them.

[petemoore]

  I'd have a lot of catching up to do in the ''turning out amazing works'' to keep up with you guys.
    Accolades ! !