ADA based through zero flanger

[danfrank]

Ok, it works! I used 75k resistors on the inverse unity op amp.
I had to troubleshoot for over an hour because of a dumb mistake I did... Note to self, TLO61 V+ is pin 7, TLO62 V+ is pin 8!
Lol!
Thank you so much PRR for your help, it worked great. Scruffie too!

[StephenGiles]

Hi everyone,
My first post here on this forum and it seems like I'm already breaking the rules with resurrecting this old thread.
Anyway, the reason I'm posting here is that I've always wanted to make a TZ flanger and I really like the A/DA flanger and it's capabilities. So I decided to make an A/DA based TZ flanger. I'm not into making PCBs so I used a couple of Lectric FX Flintlock PCBs. The first board I built as a standard A/DA flanger and I used the second board as the straight delay signal. On this second board, I also assembled the components for the "manual" control and LFO to give this project more options.
Here is a quick and dirty video of the flanger in action:

https://youtu.be/BDZwlXhW4NE

One thing I have not figured out and it would definitely be a huge asset to this project, is how to configure the second LFO to run opposite of the first LFO. Anyone have any ideas because I'm stumped! I do know that the LFO on the A/DA sweeps from 2.5 - 11.5 volts, referenced to ground.
Also, I was looking at other old threads on this forum and saw something about an old WEM Hyperflanger? Anyone have documentation on that? It sounds really interesting.
Again, I apologise for this necro-post but it is the same topic as this thread.
Thanks.

All I have on the Hyperflanger!
https://www.dropbox.com/sh/lzgsyhhkmwit7hp/AAAklyGsjnoc92t93xtY7lBXa?dl=0

[danfrank]

 Thank you so much Stephen.
BTW, did you ever get your ADA TZF working?
Thanks again.

[StephenGiles]

Thank you so much Stephen.
BTW, did you ever get your ADA TZF working?
Thanks again.

No because it was no more than an idea at the time! But if it worked for you - well done!!

I found a later drawing

[StephenGiles]

Incidentally, I'm not sure if WEM ever marketed the Hyperflanger. I was given the circuit info and bought the pcb from its designer Alan Bradford over 30 years ago.

[danfrank]

Interesting! The concept on the Hyperflanger is great but at the clock speeds of 40-100kHz, the sweep ratio is low compared to other flangers. That could be cured with substituting another clock that can swing a wider clock ratio.
Did you ever get a chance to build the PCB up? I'd be interested to see how it sounds.

[StephenGiles]

Yes I did and it sounded OK.

[danfrank]

Here's another video of the ADA TZF in action. The opposing LFOs work like a charm! Please excuse the crappy cell phone video:

https://youtu.be/h4hC-y1KNcQ

[12Bass]

Sounds great!

[Kevin Mitchell]

Super cool work, dude. It has me thinking about a few things for the ADA. Like how easily one could modify the original ADA (with a dual BBD) to do this same thing - well, with half the delay sample rate. I'm also thinking about any advantages to widening the clock ratio even further - which would be more practical with a 512 stage BBD as we're not pushing the device way beyond it's operating conditions.
If you hadn't come up with a name yet here's one that you may fancy, the Vestibular Modulator .

-KM