Tremolo Idea (555 timer)

I'm fairly handy when it comes to electronics, but I know very little about designing them. But I had this idea and maybe some of you could give me a little input on this.

Would it be possible to make a Tremolo based around a 555 timer to control the pulses of the volume drop? I'm aware you would have to use either some sort of op-amp or transistors to drive the signal through. But is this at all possible? Would it sound halfway decent?

Just a thought.

Here you go:

The Tremulous Bear

regards, Jack

I've had this idea for a while also.

Maybe have the 555 timer switch on/off a solid state relay? I think those can switch fast enough.

Have a buffer in front. Split the signal. One goes to the relay (and is either grounded or put forward to the input jack depending on the status of the relay) and the other goes to a simple voltage divider volume pot (which will be the depth control).

Wouldn't that work?

That will be an extremely choppy tremolo (square wave basically).

The history of tremolo and vibrato are cool to read up on. Tremolo just varies the volume. What I'd like to get or build is a tremolo in a foot pedal design. A tremolo actually modulates the tone up and down vs the volume.

It would be alot neater than using a whammy bar or bending notes. I know they have some digital stuff like the boss floor boards where its done digitally and is what may have to be done, But I'd like to try doing it like the old Magnatone amps did. http://www.vibroworld.com/magnatone/vibrato.html

The issue I had with using a 555 for tremolo is the clock noise coming through - but provided you shield and lay out properly it ought to be fine.

Thats about what I was thinking.

It doesn't seem like it would be to hard to expand on this idea.

Is there anything else than a relay that you could possibly drive the 555 output with? Does the gain of an opamp change depending on the supply voltage for example? If that is the case, maybe a smoothing cap could be used to get a smoother tremolo?

I know basically nothing on the component level of electronics.

Maybe Jack can answer your questions on this.

wow, I didnt know the Tremulous Bear uses a 555 timer. So to MakuseruSukotto, use the Tremulous bear as a starting point. You can simplify the control section to be just a speed or whatever you want. But it is a simple circiut so it should be a great place to get inspiration

I don't think this is the case. Did some thinking, and either you have the opamp without feedback loop in which case the gain will be too high to be usable (200,000) or you use it with a feedback loop in which case the gain is determined by the ratios of the resistors and the supply voltage will just determine the headroom, which might be a cool effect but not a classic tremolo.

So no, that won't work I'm afraid.

Have a look at FETs - you can use them more-or-less as voltage controlled resistors.

Here is a simple tremolo that you might try...

-Jack

yah what those guys said ^^

So you wouldn't be able to make a trem based around a 555 Timer and relay?

I know it would be very choppy, but that's what I want.

Yes, yes you would. But it you use a relay, you won't be able to get a smooth tremolo, but just square wave. If that is what you want, perfect.

Just make sure you get a solid state relay.

Ya, I need to go get some SS Relays today. I had some coil based relays in a parts box, so I built something lastnight, but I got way to much noise introduced from the relay. So would it be a better idea to use an ss relay, or transistors for switching?

I am not sure. A relay will ensure square wave operation but with a FET, you can do all kinds of smoothing on the square wave from the timer to get a smoother tremolo.

I know that you can use Transistors as switches, but I'm unsure how. And how would I get it to switch with pulses from this 555 Timer oscillator (the same one that I'm using to trigger the relay) I googled around but wasn't able to find anything about using transistors controlled by an oscillator to switch.

Well, if I recall correctly the voltage on the base adjusts the resistance between the collector and emitter. So a higher voltage on the base would give a lesser resistance between c and e.

I have no idea if this will even work but I can imagine you having to do something like outputting the 555 timer to the base, set up a voltage divider with the sound signal with a potentiometer for the resistance between the signal and ground (depth knob) and use the transistor to control the resistance between the signal and output jack.

In my head, that will work but my electronics experience is very limited and I'm sure there are problems with that way of doing it.

*edit*

I also think you need a cap after the transistor and before the output jack so that you filter out DC voltage coming form the 555 timer.

I'll give that a try here in a little while. Thanks for the help.

you can try a cmos bilateral switch (eg 4016), so if 555 outputs logical levels it can go easily into the 4016 to switch on and off.