Tap tempo modded Echo Base PCBs in the works - vote on features

[Taylor]

Unfortunately, there isn't any room left to do companding, unless people were willing to build this is something bigger than a 1590BB.

[aziltz]

the 1790NS isnt much bigger than a 1590BB, especially if you want more than 5 knobs, 2 jacks or 2 footswitches.

[jkokura]

I'll be building it into a 1590DD for one with 3 switchs, and maybe the second into a 1790NS for a version using 2 switches.

Jacob

[Taylor]

Yikes, this is a tough PCB. It's 99% there, but that last 1% is recalcitrant. I've been trying to decide how to handle the 2 delay chips. At the outset, I only thought I'd use them in series for double time. But it really does seem a shame to have 2 delay chips and not allow for crazy parallel delays.

Plus, imagine how awesome it would be to have 2 delays in parallel using the PTAP: since it allows you to do different divisions of the tapped tempo, you could set the delays to be perfectly in sync in a 4-to-3 time relationship, without having to tweak the delays really carefully. Just tap in your time and out comes a perfectly synced polyrhythmic delay!

So the only problem is doing the PCB in such a way that you can do those wacky things, but figuring out how to build it isn't a chore. I really like the majority of the build to be obvious just by looking at the board, without having to dig through a PDF, and I've mostly achieved that. But this parallel/series switching is going to be really hard to pull off cleanly.

Two separate delay lines sound cool. I remember some algorithms in my old Lexicon Vortex, you can do thing like series or parallel arrangements with some cross feedback lines...

Now that thing is one of my favorite effects units ever. I think it was the "Bleen" preset, which was like a multi-tap delay with a ring modulator in the feedback loop... that, plus an Ebow was "my sound" for awhile. I need to code up a workalike in the FV-1 chip now that I don't have my Vortex anymore.

[maximee]

Taylor, this is going to be terrific! Keep it up! 

[RonaldB]

Hello Taylor,
I want 1 board to when your done, great job.

And with 2 parrallel delays one set to 1/8* and the other on 1/4 you get an instand The Edge sound 

Ronald

[Taylor]

I'm considering adding some optocouplers to the circuit to provide a dual feedback control from one knob. My question to you guys:

Are optocouplers hard to get in Europe? I figure that with ROHS they're supposed to be banned, but it looks like Banzai has them.

Would it make the circuit harder to build for ROHS-affected countries if there were a couple of optocouplers?

[frequencycentral]

^^^

Real men roll their own.......

[Taylor]

^^^

Real men roll their own.......

True, but what about Europeans?







But anyway, it's not optocouplers only that are banned by ROHS, but CDS cells, which you need to roll your own. So I just want to confirm that it's not hard for European DIYers to get their hands on opto-things.

[frequencycentral]

I use these little guys, still readily available: http://cgi.ebay.co.uk/LDR-Light-Dependent-Resistor-Lot-of-5_W0QQitemZ120343782559QQcmdZViewItemQQptZUK_BOI_Electrical_Components_Supplies_ET?hash=item1c050c649f

Or if you're thinking a dedicated part will be more reliably accurate, this European would be OK with Banzai. 

[Taylor]

In this case I don't think accuracy matters too much, since it would be controlling feedback, so I don't think matching is that critical.

[RonaldB]

Here in europe we have lot's off places to get optocouplers.

Ronald
The NEtherlands

[Skruffyhound]

Maybe it's a ploy to get us to buy 20yrs worth of LDR's each. Let's build with them while we've got 'em.

[NQbass7]

The PCB design is not quite done. I will probably finish it in the next couple of days. Then it'll be a week and a half until I get the prototypes. Then another 2 weeks for the big batch to be made. So we're probably about a month from the point I can start actually shipping boards.

Awesome, thanks.  I'm definitely in for two of the boards.. I can't wait for this thing.  I'm just finishing up a rebote which should keep me tided over, but I'm looking forward to one or two of these to play around with...

[bluesdevil]

Really hoping it ends up with the parallel delays feature or even greater, capability of parallel and series.
   Also I hope you don't get hung up fitting it for a little box and sacrifice some features... good luck!!!

[Taylor]

Yep, it's looking like you'll have the ability to do parallel and series, but it will require a 4PDT toggle switch, which is $6. You're right that I am kind of hitting up against a wall since I designed this for a BB from the outset. I think it will still fit in a BB, but to get the full features you'll want a 1790 or bigger.

I'm still going back and forth between a dual pot and an optocoupler solution - talking to Small Bear about them carrying the PC mount dual pot.

[bluesdevil]

That's great news. $6 extra for a toggle is a small price to pay for this feature. yeah, go all the way and make your efforts count.
     
   
   

[Taylor]

Is there a way to have it either be a mix pot or a level pot? Like depending on the builders desire? Or is that a part of the PCB that's either one or the other.

Is there a reason you'd prefer a level pot to a mix pot? Originally I wanted as much flexibility as possible, but as the board gets more complex, this is harder to maintain. I'm thinking I will go with one or the other. The Mix pot seems more versatile to me. What do you think?

Also, as this project becomes larger, I wonder if there would be interest in a different board that was just a stock Echo Base? Smaller, simpler, less options, but easier and cheaper to build, and still with the luxuries of silk screen, solder mask, and plated pads. This simple one could even fit in a 1590B. Does that appeal to anyone?

[jkokura]

I would take one straight Echo Base pcb, and I'm in for 2 of the bigger ones.

Jacob

[Ry]

I'm all for the mix pot.

As for a simpler board, I'd get a couple, but I'm REALLY excited about getting some of the Super tricked out boards!  .  I don't care how big it is, I'll put it in a rack if I have to.

Ry