Building the tap tempo tremolo

[lwatford]

So the first one I built the guy wants some changes to...

How would I go about taking out the rate knob? Just Jumper across it? Or can I just leave it out entirely?

Is it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.

Basically I need to dumb it down a to the Depth knob, sine/square(or maybe triangle) switch, & quarter/eighth switch (I think, not really sure yet). Oh, and add an external jack for tap tempo.

[lwatford]

So the first one I built the guy wants some changes to...

How would I go about taking out the rate knob? Just Jumper across it? Or can I just leave it out entirely?

Is it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.

Basically I need to dumb it down a to the Depth knob, sine/square(or maybe triangle) switch, & quarter/eighth switch (I think, not really sure yet). Oh, and add an external jack for tap tempo.

So taking the rate knob out works great, are there any issues that could happen doing it that way?

I'll try switches next...

[lwatford]

So the first one I built the guy wants some changes to...

How would I go about taking out the rate knob? Just Jumper across it? Or can I just leave it out entirely?

Is it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.

Basically I need to dumb it down a to the Depth knob, sine/square(or maybe triangle) switch, & quarter/eighth switch (I think, not really sure yet). Oh, and add an external jack for tap tempo.

so my first attempt at switching didn't work...I'm not sure I quite understand what is being done with the control voltage and the multiple switch.
So taking the rate knob out works great, are there any issues that could happen doing it that way?

I'll try switches next...

[.Mike]

So taking the rate knob out works great, are there any issues that could happen doing it that way?

I'm not sure of the consequences of removing the tempo knob. If I recall correctly, when I was putting together the non-tap version of this, Tom (who designed the LFO) told me that you shouldn't leave any unused CV pins floating.

I'm not sure how this applies to the tap tempo version of the LFO, though, since the tempo CV is overridden with the tap value.

Either way, the solution is easy: put a jumper between the middle pin of where the tempo knob was, and the pin that connected to ground.

Is it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.

Totally possible.

Page 8 of the LFO Datasheet will help you do this. It shows hot to replace both the waveform and multiplier selectors with rotary switches.

You need to use this diagram to work out a voltage divider to connect to your switches. For example, if you wanted the 2nd and 7th waveforms, you would setup something like this:

|5v---\/\/\/15k\/\/\/---|---\/\/\/50k\/\/\/---|---\/\/\/15k\/\/\/---Gnd|

Use an SPDT toggle, and connect the middle lug of your switch to where the middle lug of the pot you removed was connected. Connect one lug of the switch to where the first 15k and 50k meet (waveform #2), and the other lug to where the 50k and the second 15k meet (waveform #7).

I hope that helps.

Mike

[lwatford]

thanks for the help! I got the two waves I want, going to work on the multiplier next. Will it be any different because of the two unused positions?

So taking the rate knob out works great, are there any issues that could happen doing it that way?

I'm not sure of the consequences of removing the tempo knob. If I recall correctly, when I was putting together the non-tap version of this, Tom (who designed the LFO) told me that you shouldn't leave any unused CV pins floating.

I'm not sure how this applies to the tap tempo version of the LFO, though, since the tempo CV is overridden with the tap value.

Either way, the solution is easy: put a jumper between the middle pin of where the tempo knob was, and the pin that connected to ground.

Is it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.

Totally possible.

Page 8 of the LFO Datasheet will help you do this. It shows hot to replace both the waveform and multiplier selectors with rotary switches.

You need to use this diagram to work out a voltage divider to connect to your switches. For example, if you wanted the 2nd and 7th waveforms, you would setup something like this:

|5v---\/\/\/15k\/\/\/---|---\/\/\/50k\/\/\/---|---\/\/\/15k\/\/\/---Gnd|

Use an SPDT toggle, and connect the middle lug of your switch to where the middle lug of the pot you removed was connected. Connect one lug of the switch to where the first 15k and 50k meet (waveform #2), and the other lug to where the 50k and the second 15k meet (waveform #7).

I hope that helps.

Mike

[.Mike]

thanks for the help! I got the two waves I want, going to work on the multiplier next. Will it be any different because of the two unused positions?

Yeah, check out the datasheet again... "The top two options are not used for the Multiplier."

You still have to account for the resistance of the top two positions-- just like you would with the waveform-- it's just that there are only six possible multiplier settings.


And btw, I had the reference to the two waveforms reversed in my last post... should be:

Connect one lug of the switch to where the first 15k and 50k meet (waveform #7), and the other lug to where the 50k and the second 15k meet (waveform #2).

Mike

[lwatford]

that's what I thought, just wanted to double check! Thanks again!

thanks for the help! I got the two waves I want, going to work on the multiplier next. Will it be any different because of the two unused positions?

Yeah, check out the datasheet again... "The top two options are not used for the Multiplier."

You still have to account for the resistance of the top two positions-- just like you would with the waveform-- it's just that there are only six possible multiplier settings.


And btw, I had the reference to the two waveforms reversed in my last post... should be:

Connect one lug of the switch to where the first 15k and 50k meet (waveform #7), and the other lug to where the 50k and the second 15k meet (waveform #2).

Mike

[azrael]

hey guys, got a bit of an issue here. With the waveform knob, I'm not getting a random waveform at the end of the taper. the effect just shuts off. thoughts?

got a bit of ticking, dialed it out, but the level seems kind of low. might have to change the gain trimpot so I can get it up to line level!

Any more ideas on this?

[Taylor]

What do you mean when you say you can't tell what voltage is coming out of the pot's wiper when set to random?

[azrael]

Wow. Eff me! I went over the whole offboard wiring and circuit with a multimeter, I had the freakin' waveform pot hooked up wrong! mixed up legs 2 and 1. 
works fine now.

[Taylor]

  Glad it got sorted.

[lwatford]

Thanks for the help!!

I got the switch working, but decided to just put in a rotary switch for the multiplier...cause I knew if I didn't, I would end up doing it later! Picky people! It's now a nice mess inside, but I don't know how to make it much better. The way the box is drilled isn't ideal, but since his kids did it up when it had something else in it, I can't really change it out.

I'm going to change the tap tempo switch to one of the soft touch ones that other people have been using, they seem lots better than the xwing one that's in there.

So here it is:




and just because...here's mine:

[telebiker]

Hello!
I'm very interested in building the circuit. I want to make 2 pedals and connect them in series in order to make some interesting effects, for example, setting one really slow with a light depth and then the other really fast with a heavy depth. I want to synchronize one tempo from another pedal. Using multiplier feature it's possible to make fast from slow and slow from fast. Pin 7 of the chip provides clock output.

First question: how can I get clock input?
Second: is there a way to make fine adjustment of the tempo which is provided by another pedal? Setting both tremolos to speeds that are close but different will also make some interesting effects.
Third: is there a way to move starting phase of the wave?

Thanks.
Any comments would be very appreciated. For the diagrams can't even ask.

[.Mike]

First question: how can I get clock input?

I don't think you can. The easiest way, though, is to use on rate CV, and use it for both LFOs. That will sync them.

Second: is there a way to make fine adjustment of the tempo which is provided by another pedal? Setting both tremolos to speeds that are close but different will also make some interesting effects.

Not an easy, built-in way, no.

Third: is there a way to move starting phase of the wave?

Not without editing the code, no.

Mike

[telebiker]

Thanks.
I think I will use one tap-tempo in for both LFO's (not one rate pot), seems doable. That will sync them too, right? As for speeds that are close but different, I think, I will be satisfied with two individual rate pots. Tell me please if I'm saying a rubbish.

Wave moving would be so useful for building a stereo tremolo.

[Hides-His-Eyes]

All sounds sensible.

[Taylor]

If you tap the tap switch a single time, it resets the wave phase to the time you tapped. If I understand what you're trying to do, this would do it, although not perhaps with as much control as you want. You can have your two trems going in sync, then hit the tap switch on one one them when the other is in the off phase of the cycle, to get panning.

[telebiker]

If you tap the tap switch a single time, it resets the wave phase to the time you tapped. If I understand what you're trying to do, this would do it, although not perhaps with as much control as you want. You can have your two trems going in sync, then hit the tap switch on one one them when the other is in the off phase of the cycle, to get panning.

That's great idea, but how can I combine two tap tempo inputs at one LFO?

[Used666]

Here's mine :





I need to redo the switch wiring as I'm getting the bypass tick but other than that it's great

[turunturun]

Anyone have experience (either actual or theoretical) with CV implementation in this pedal?

So after rebuilding the PCB with a new one I got my TTT working - it works pretty much perfect in stock config.

However, I installed a CV input jack for the division/multiplier and that works also.....but adds a ferocious audio pop whenever the voltage changes.
I am using a Moog MP201 to send a square wave voltage between two settings and on each "edge" of the wave there is a pop. It only happens when the mp201 is sending voltage. If the voltage is off, but the cable still connects the devices its quiet.

My method for wiring up the jack was to connect the tip lug to the center wiper of the division knob. The build guide made no mention of what to do with the sleeve connection on the jack so I didn't connect that to anything.

So the build guide mentioned adding a resistor in series with the CV connections to "limit current" but I didn't do that....could that be causing it?
Any other ideas?

Here is a video of the issue that may help:
http://youtu.be/ArLF7KAXp-A

And here are the build pics (from before I replaced the circuit board with the new one, but everything else stayed the same)



high res here:
http://www.flickr.com/photos/jasonandlindy/5597246531/



high res here:
http://www.flickr.com/photos/jasonandlindy/5597246371/