Author Topic: Diy BBD possible?  (Read 1016 times)

PRR

Re: Diy BBD possible?
« Reply #20 on: June 27, 2020, 01:39:20 AM »
> 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/
« Last Edit: June 27, 2020, 01:41:27 AM by PRR »

Scruffie

Re: Diy BBD possible?
« Reply #21 on: June 27, 2020, 08:14:57 AM »
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.
« Last Edit: June 27, 2020, 08:19:13 AM by Scruffie »

ElectricDruid

Re: Diy BBD possible?
« Reply #22 on: June 27, 2020, 02:49:28 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

Re: Diy BBD possible?
« Reply #23 on: June 27, 2020, 04:21:45 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

Re: Diy BBD possible?
« Reply #24 on: June 27, 2020, 04:48:01 PM »
50 pedals and counting!

11-90-an

Re: Diy BBD possible?
« Reply #25 on: June 30, 2020, 02:54:28 PM »
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
« Last Edit: June 30, 2020, 03:21:19 PM by 11-90-an »
1 toasted transistor so far

PRR

Re: Diy BBD possible?
« Reply #26 on: June 30, 2020, 11:47:19 PM »
> 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.

11-90-an

Re: Diy BBD possible?
« Reply #27 on: July 01, 2020, 12:38:56 AM »
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:
1 toasted transistor so far

PRR

Re: Diy BBD possible?
« Reply #28 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.

11-90-an

Re: Diy BBD possible?
« Reply #29 on: July 01, 2020, 04:00:20 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
« Last Edit: July 01, 2020, 06:27:50 AM by 11-90-an »
1 toasted transistor so far

EBK

Re: Diy BBD possible?
« Reply #30 on: July 01, 2020, 06:08:40 AM »
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
No affiliations. If I glowingly mention specific merchants or products, it is because I like them without having to be paid to like them.

antonis

Re: Diy BBD possible?
« Reply #31 on: July 01, 2020, 06:41:37 AM »
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

Re: Diy BBD possible?
« Reply #32 on: July 01, 2020, 03:24:33 PM »
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

Re: Diy BBD possible?
« Reply #33 on: July 02, 2020, 08:27:18 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

Re: Diy BBD possible?
« Reply #35 on: July 02, 2020, 02:47:52 PM »
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!
No affiliations. If I glowingly mention specific merchants or products, it is because I like them without having to be paid to like them.

vigilante397

Re: Diy BBD possible?
« Reply #36 on: July 03, 2020, 02:15:18 PM »
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
« Last Edit: July 03, 2020, 04:07:07 PM by vigilante397 »
"I'm not sure what "serious design flaws" you see. Does it explode or poison your dog?" - PRR

www.sushiboxfx.com