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Projects => Build Reports => Topic started by: moosapotamus on August 18, 2020, 09:14:35 AM

Title: Dual Cave Dweller Delay
Post by: moosapotamus on August 18, 2020, 09:14:35 AM
I've had these two Cave Dweller PCBs populated for a while (Rev.1). Finally found the time to box them up.

Knobs for time and dwell for each delay. The single echo toggle replaces the echo pots for each delay... turns the single repeat for both delays on/off simultaneously. The cross toggle does cross feedback... sends the feedback (dwell) from each to the other delay. The middle toggle switches between series and parallel operation.

I used a switching jack for a second output to be able to send each delay to separate mixer inputs. With nothing plugged into out2, both delays get mixed to out1.

I kinda rushed the waterslide decal, so the graphics look a little heavy handed. Goofed on the knobs, too. Pots are d-shaft, and the knobs turned out to have the 'd' rotated 180. But I still think the Cave Dweller is a cool sounding delay. And doubled up makes it even more fun to play!

(http://moosapotamus.net/images/IMG_1766)

(http://moosapotamus.net/images/IMG_1767)
Title: Re: Dual Cave Dweller Delay
Post by: dan.schumaker on August 18, 2020, 09:29:07 AM
That looks really cool!  An awesome idea!  Care to explain the series/parallel switching a little more?
Title: Re: Dual Cave Dweller Delay
Post by: jimilee on August 18, 2020, 11:38:18 AM
Niiice! Haven't seen you in a while now.


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Title: Re: Dual Cave Dweller Delay
Post by: cooder on August 18, 2020, 02:07:31 PM
Great stuff and sounds like a Pandoras box! Woud be cool to find out more about the switching and sounds you can get with that, maybe a demo video if you could?
Title: Re: Dual Cave Dweller Delay
Post by: moosapotamus on August 19, 2020, 03:38:46 PM
You know... work tends to interfere with my personal interests. But I finally have the time for more DIY, now!

I'll try to do a demo video asap. Meantime, here is a little more of an explanation of how I did the switches...
I should also add that I used B10k for the Dwell pots, instead of B50k. With B50k, I was getting runaway feedback for more than half of the pot's rotation.

Cross Feedback DPDT toggle
For normal operation, the wiper of the Dwell pot for pcb1 is sent to pad 2 on pcb1, and the wiper of the Dwell pot for pcb2 is sent to pad 2 on pcb2.
For cross feedback, the wiper of the Dwell pot for pcb1 is sent to pad 2 on pcb2, and the wiper of the Dwell pot for pcb2 is sent to pad 2 on pcb1.

Series/Parallel DPDT toggle
For Serial operation, the signal path first goes through one of the delays, and the output of that delay goes to the input of the second delay.
For Parallel operation, the signal path is split to the input of both delays, and the output of both delays are mixed to the output.

Echo DPDT toggle
Each side of the DPDT replaces one of the two Echo pots.
To enable the Echos, the switch shunts pad 2 to pad 3.
To disable the Echos, the switch connects pad 2 to ground, and places 47k between pads 2 and 3.
Echo Pad 1 on both pcbs was left unconnected.

(http://moosapotamus.net/images/DualCDswitches.png)

Of course, there may be other/better ways to do some of this stuff. So, please feel free to comment.
I think most of this could be applied to any pair of delay circuits. Doesn't necessarily have to be the Cave Dweller.
Title: Re: Dual Cave Dweller Delay
Post by: TGP39 on August 19, 2020, 11:48:26 PM
There is so much to learn on this one.  Thank you for sharing your knowledge once again. It has truly been missed. 
~Steve
Title: Re: Dual Cave Dweller Delay
Post by: moosapotamus on August 20, 2020, 05:19:04 AM
Quote from: TGP39 on August 19, 2020, 11:48:26 PM
There is so much to learn on this one.  Thank you for sharing your knowledge once again. It has truly been missed. 
~Steve

Cheers, Steve!
Title: Re: Dual Cave Dweller Delay
Post by: madbean on August 20, 2020, 05:33:12 AM
Images don't seem to be showing up for me.
Title: Re: Dual Cave Dweller Delay
Post by: moosapotamus on August 20, 2020, 12:38:43 PM
Quote from: madbean on August 20, 2020, 05:33:12 AM
Images don't seem to be showing up for me.

Sorry, not sure what the problem could be. Try clicking on 'quote' and copy/paste the image URL to your address bar. I don't really know what I can try on my end, but I'm open to suggestions.
Title: Re: Dual Cave Dweller Delay
Post by: jimilee on August 20, 2020, 02:55:15 PM
Quote from: moosapotamus on August 20, 2020, 12:38:43 PM
Quote from: madbean on August 20, 2020, 05:33:12 AM
Images don't seem to be showing up for me.

Sorry, not sure what the problem could be. Try clicking on 'quote' and copy/paste the image URL to your address bar. I don't really know what I can try on my end, but I'm open to suggestions.
I can see it, maybe you broke yours, Brian.


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Title: Re: Dual Cave Dweller Delay
Post by: alanp on August 20, 2020, 06:03:42 PM
Niiice. Where'd the wire come from? For me, it has a very oldschool Electronics Kit flavour to it. (You know, the kind that came with a 741 in the pride of place and you had to assemble the "breadboard" yourself out of metal clips and a plastic frame.)

Half-surprised you didn't make the second Cave Dweller a Dub Dweller board. The Dub Dweller is very cool!
Title: Re: Dual Cave Dweller Delay
Post by: moosapotamus on August 21, 2020, 02:02:21 PM
Thanks, alan. The wire is from ebay - teflon coated 22awg (don't recall the sellers).

Dub Dweller?!?! Where can I find more info about that?

Actually, I doubt the Dub Dweller even existed back when I originally populated those PCBs. Those are Cave Dweller v1.0 PCBs (yes, it was a while ago). I wired them both up to a breadboard to verify and iron out the dual setup, but never got around to actually boxing it up until recently. But, two different sounding delays in one box would be cool!
Title: Re: Dual Cave Dweller Delay
Post by: diablochris6 on August 22, 2020, 10:42:54 AM
Great idea. I think I've made delays that do one or two of these but never all three.