Diy BBD possible?

Started by 11-90-an, June 24, 2020, 12:09:50 AM

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PRR

#20
> buy yourself a 50ft garden hose ............... .............. ............. an awful lot of trouble to go to for something that may sound interesting but won't sound especially good. linkback

And yet: this was a commercial product taken-up by a Big Brand. Cooper Time Cube. ("timecube" is totally a different thing.)

https://media.uaudio.com/blog/2009/05/doctors_03.jpg
https://reverb.com/item/2486446-vintage-urei-cooper-time-cube-stereo-acoustic-delay
https://www.uaudio.fr/blog/wiggly-frequency-response-cooper-time-cube/
https://forum.fractalaudio.com/threads/cooper-time-cube-a-delay-through-a-garden-hose-can-we-axe-it.141354/
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Scruffie

#21
Quote from: ElectricDruid on June 26, 2020, 08:40:15 PM
There are still things I'd like to see that we don't have, and I don't understand why modern chips seem to have worse clock input capacitance than the originals, but there's definitely plenty of options.
Hold up, did I miss that in the new data sheets? Or is that from experience.

Or did you mean Reticon vs. Panasonic.

Any way, I built a CMOS based BBD to play with some sample rate reduction, fun, but rubbish. Can't see why you'd want a home-brew for any real world purpose.

ElectricDruid

Quote from: Scruffie on June 27, 2020, 08:14:57 AM
Quote from: ElectricDruid on June 26, 2020, 08:40:15 PM
There are still things I'd like to see that we don't have, and I don't understand why modern chips seem to have worse clock input capacitance than the originals, but there's definitely plenty of options.
Hold up, did I miss that in the new data sheets? Or is that from experience.

No, it's in the data sheets. Compare CoolAudio with the old MN-series:

   MN3208: 1400pF, V3208: 2800pF

Interestingly, the difference disappears when you get to the 4096-stage device:

   MN3208:2800pF, V3205: 2800pF

   MN3207: 700pF, V3207: ???
I'm pretty sure I've seen a similar disparity for the 3207, but the V3207 datasheet seems to have dropped that information now. I can't even find datasheets fro the Xvive clones, so if they know, they're not telling.

Honestly though, I'm not sure I trust Coolaudio's datasheets. They look look copy-pasted from somewhere else, so I don't know that I believe all the figures. Maybe they're really the same, I don't know. I should test it, I guess.

Scruffie

Quote from: ElectricDruid on June 27, 2020, 02:49:28 PM
Quote from: Scruffie on June 27, 2020, 08:14:57 AM
Quote from: ElectricDruid on June 26, 2020, 08:40:15 PM
There are still things I'd like to see that we don't have, and I don't understand why modern chips seem to have worse clock input capacitance than the originals, but there's definitely plenty of options.
Hold up, did I miss that in the new data sheets? Or is that from experience.

No, it's in the data sheets. Compare CoolAudio with the old MN-series:

   MN3208: 1400pF, V3208: 2800pF

Interestingly, the difference disappears when you get to the 4096-stage device:

   MN3208:2800pF, V3205: 2800pF

   MN3207: 700pF, V3207: ???
I'm pretty sure I've seen a similar disparity for the 3207, but the V3207 datasheet seems to have dropped that information now. I can't even find datasheets fro the Xvive clones, so if they know, they're not telling.

Honestly though, I'm not sure I trust Coolaudio's datasheets. They look look copy-pasted from somewhere else, so I don't know that I believe all the figures. Maybe they're really the same, I don't know. I should test it, I guess.
The Xvive datasheets bar the MN3005 just link to the original Panasonic ones.

But so it does, I even have an older copy of the v3208 datasheet saved and it says it on that too... how weird.

rankot

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60 pedals and counting!

11-90-an

#25
Just thought about something right now and wanted to ask you folks...

So apparentlay how an octave up works using CMOS is using a XOr gate as an edge detector by delaying the signal a bit with some NOT gates...



Just wondering what would happen with, say, 36 of those NOT gate stages (without XOR)? I know that this would be very fuzzy... so probably could be fixed(ish) with a square wave to sine wave converter? Would add a mix pot as well.. what do you guys think? (Obviously would be impractical but hey, its experimentation... 8) )

EDIT: googled a bit, and came to this realization...

https://en.m.wikipedia.org/wiki/Propagation_delay

- 1 logic gate has a genaeral maximum delay of about 10 nanoseconds(ns) so for a 500ms delay you would need 5000 NOT gates... about 834 cd4069s...

- it would be better to use wire, as it states in wikipedia that 15cm of wire has about 1ns delay... so that would be 750meters of wire for 500ms delay.... about $20 if you use very cheap wire...

Hope this would enlighten other people trying to attempt a no-bbd delay... haha :D
flip flop flip flop flip

PRR

> 750meters of wire for 500ms delay....

That can't be right? You or the Wiki has slipped a decimal-bead somewhere?

It says that a mile of wire is a milli-Second, so here to Grandma's is a whole second. Even in the bad days of municipal Missouri telephone operations, she wasn't that far away.

And that calls switched through a geo-sync satellite (we used to do that!) would be most of a minute round-trip. We stopped routing voice through geo-sync satts but the latency was not THAT bad.

I learned it as "light travels 1 nanosecond per foot". This proves that GHz computers can never be made. (Not in days when computers were the size of a truck.) (Yes, I am typing at a 3GHz computer....)

That's naked light. In a wire (or a optic-fiber) is slower and I will not argue 15cm=6" is a nano in wire. (I'd expect 7 or 8 inches but what's the point?)

I get 189 miles (303km) makes 1 milliSecond. ?? 17mS across the USA, 34mS there and back. 64mS in slow wire. ???

About like 50 feet of garden hose. And as bad as hose losses are, wire-losses are worse.

While sub-mS delays can be useful in audio (and I guess are the specialty of BBDs), many-mS delay opens more possibilities.
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11-90-an

oh wait... my calculations were wrong.... i was typing ver late at night... it should be 75,000meters, not 750.... more realistic haha :icon_redface:

chorus is about 20ms-50ms... that should be about 3kilometers to 7.5km....  :icon_mrgreen:
flip flop flip flop flip

PRR

Geostationary is  35,786 km (22,236 mi) up and radio signals take approximately 0.25 of a second to and fro.
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11-90-an

#29
Quote from: PRR on July 01, 2020, 01:16:28 AM
Geostationary is  35,786 km (22,236 mi) up and radio signals take approximately 0.25 of a second to and fro.

so making a pedal that would convert guitar signals to radio signals and bounce it off geostationary twice, in theory, have 0.5 seconds delay / 500ms... hmmm  ???  :o
flip flop flip flop flip

EBK

A few years ago, we had a rather interesting conversation here about some rather impractical, yet thought-provoking delay techniques.  My favorite involved the moon.
https://www.diystompboxes.com/smfforum/index.php?topic=116204.0
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Technical difficulties.  Please stand by.

antonis

And a few years later, new forum members will be astonished of discussion substances made a few years ago.. :icon_lol:
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

amptramp

Here is the thread for all of our predictions, some of which have not happened due to lack of imagination and other which have not happened due to common sense:

https://www.diystompboxes.com/smfforum/index.php?topic=105617.0

In it, I proposed a wax cylinder delay where the music is recorded onto a wax cylinder, picked off at a variable tap angle for variable delay and heated to erase then cooled to form a hard wax surface, all in one revolution.

We also had a moonbounce delay but it is a fixed 2.58 second delay and it is only available during half of the day.

GFR

Quote from: 11-90-an on July 01, 2020, 04:00:20 AM
Quote from: PRR on July 01, 2020, 01:16:28 AM
Geostationary is  35,786 km (22,236 mi) up and radio signals take approximately 0.25 of a second to and fro.

so making a pedal that would convert guitar signals to radio signals and bounce it off geostationary twice, in theory, have 0.5 seconds delay / 500ms... hmmm  ???  :o

You can use the delay of a "Facebook Live" :) Several seconds!

https://www.youtube.com/watch?v=lO9d-AJai8Q


EBK

Quote from: GFR on July 02, 2020, 08:27:18 AM
You can use the delay of a "Facebook Live" :) Several seconds!

https://www.youtube.com/watch?v=lO9d-AJai8Q
That's very cool, and a catchy tune too!
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Technical difficulties.  Please stand by.

vigilante397

#36
Quote from: GFR on July 02, 2020, 08:27:18 AM
You can use the delay of a "Facebook Live" :) Several seconds!

https://www.youtube.com/watch?v=lO9d-AJai8Q

I expected to watch a couple seconds, say "neat," and be on my way. Six minutes later I'm looking up more of that band. Super cool stuff.

EDIT: A couple hours later I now own that band's album :P
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"Some people love music the way other people love chocolate. Some of us love music the way other people love oxygen."

www.sushiboxfx.com

PRR

Quote from: antonis on July 01, 2020, 06:41:37 AM.... years later, .... discussion substances made a few years ago.. :icon_lol:



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