Anybody that built the Tremulus Lune

[Marcos - Munky]

What is the resistance of the LDR that you used?

[mikeb]

Marcos - it says in the parts list the resistance goes from 5k light to 500k dark, but the LDR isn't critical. You'll note there is a trimpot, hence the amplitude attenuating effect of the opamp stage is adjustable to suit the parameters of the LDR. Anything with a dark resistance of 100k to 1M or more should be fine - if more, you could always limit the resistance by placing a resistor in parallel.

Anything you have in your parts box should work. That's what I use!

Mike

[Marcos - Munky]

Thanks a lot, Mike. I will try with one that I have here.

[travissk]

I went ahead and ordered the suggested one, Mouser Part No. 338-54C348

3K-20K light resistance
500K dark resistance
30mW maximum power

I'd agree that whatever you have should work fine, especially if the dark resistance is higher (the other models in the Mouser catalog go to 20M dark)

Awesome sounding pedal, hope the build goes smoothly and you enjoy it!

[Marcos - Munky]

I will test it today. I finished it, just need the switch. I don't know the values of the LDR, but I'm sure it goes from about 4K light and more than 1M dark.

[axr]

marcos i`ve used one 10k and 1m (dark) without a problem

[Marcos - Munky]

I tested it, it sounds really beautiful. I just have one problem, it distorts the sound a little, but it's a cool distorted sound. Maybe I will keep the distortion as a feature of the effect.

[mikeb]

Hi Marcos

It isn't supposed to distort , so if you decide to do something about it look at the tweaking docs on this page:
http://commonsound.com/tremulus.html
specifically page 2 (relates to undwanted distortion).

BTW, what dual opamps did you use?

Mike

[Marcos - Munky]

Hi Mike. I will take a look. I used the suggested ones, a TL072 and a JRC4558.

[Marcos - Munky]

I found the problem. It was the trimpot setting. Now it's clean, but I let it a little distorted. I think this gives a little color to the sound.

[mikeb]

Excellent - often a little distortion makes MOST effects sound better (non-distortion effects) ...

Mike

[Jason D]

I am using the Tremulus Lune for a school senior project.
Could anyone tell me what basic circuit the LFO is based on?
And, any equations to figure out what is going on?


Thanks.

[mikeb]

Look through app notes for opamps - this info is all in there.

Mike