DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: lh_satch on September 28, 2005, 01:18:08 PM

Title: Tap Tempo Osccilator
Post by: lh_satch on September 28, 2005, 01:18:08 PM
Hi
I am currently studying my final year at Uni and for my end of year project I would like to make a tap tempo osccilator (tremolo) unit.  Could anyone tell the best place to find a schematic for a tap tempo project.

Thanks

Martin
Title: Re: Tap Tempo Osccilator
Post by: aron on September 28, 2005, 01:19:31 PM
Most of these I have seen have been digital. Is there an analog tap tempo in a pedal?
Title: Re: Tap Tempo Osccilator
Post by: gez on September 28, 2005, 02:11:11 PM
Quote from: aron on September 28, 2005, 01:19:31 PM
Is there an analog tap tempo in a pedal?

The only thing I know of in the analogue world that's remotely close is synching of the LFO to the initial attack of a note/chord/accidental bang of headstock on speaker cabinet.  Other than that I think you're going to have to go digital...
Title: Re: Tap Tempo Osccilator
Post by: R.G. on September 28, 2005, 02:20:15 PM
I did just come up with an implementable analog tap tempo oscillator. Mostly analog, anyway.

You use a digital controller to measure the tap time, then put out the right LFO frequency from the controller. That's the digital part.

The analog part is to phase lock the analog oscillator to the digital output. I think that a single CD4046 would do the trick. Capture time is going to be a problem, so the design of the loop is going to be important.
Title: Re: Tap Tempo Osccilator
Post by: nikStomp on January 13, 2008, 08:17:21 PM
Hello R.G.
I'm really interessed in your circuits can you post a schematic?

Thanks

Nicola

ps do you think that this http://www.tomwiltshire.co.uk/sdiy/envgen.html
can work in a tremolo circuit for synth like sounds?

Title: Re: Tap Tempo Osccilator
Post by: gez on January 14, 2008, 04:32:30 AM
IIR, there's a PIC project in the digital forum: well, the code at any rate.
Title: Re: Tap Tempo Osccilator
Post by: R.G. on January 14, 2008, 09:32:52 AM
I haven't built one yet, only figured out how to do it. There's a lot of digging to be done between here and there.

One thing about programmable controllers is that the schematic is almost useless. There is a power supply in, maybe some switches and pots that connect directly to pins on the controller, and then outputs from other pins. The controller becomes all there is, and you can't tell from the schematic what the insides do. It becomes A Simple Matter of Programming - which most people will tell you isn't all that simple.

I read once that computers have a way of hollowing out whatever they get into. Eventually, there is the computer, and all inputs and outputs go directly into and out of it. Everything else is 'eaten up' by the computer chip.

Quoteps do you think that this http://www.tomwiltshire.co.uk/sdiy/envgen.html can work in a tremolo circuit for synth like sounds?
Yes.

Even more interesting is the VCLFO at the same site. It could easily be made into the replacement for the PLL, or the entire tap tempo chip. However, it's A Simple Matter Of Programming, and in this case, someone else's programming.