Echo Base - a new PT2399 delay

Started by slacker, August 27, 2007, 04:33:19 PM

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ringworm

Does anybody know the metric dimensions for either of the Echo Base pcbs by anonymousfacelesscoward?
Much appreciated.

slacker

Quote from: bayonetblue on February 09, 2009, 04:10:47 PM
What type of stomp switch is used in this circuit?

It only needs a SPST, but you can use SPDT or DPDT or even a 3PDT foot switch, and just use 1 pole and 1 throw of them.

slacker

Quote from: andrew_k on February 10, 2009, 06:26:43 AM
REPEAT CLIPPING If your echo base build has distorted repeats (but clean bypassed signal) remove the clipping diodes next to the feedback pot.

I love it when the simplest solution is the one that works!  ;D

Cool :)

With the bleed through does it stop if you turn the level all the way down? If it does then it might be worth trying a different CD4066 to see if there's a problem with yours.

cardinale

just drop by to say thank you!
I was just about to buy a used DD-3 but then i found this thread.
cuz this was my 1st DIY.. it took me a month to build it (on and off). But I'm glad I did it. Way more cheaper & way more satisfied than DD-3.

here's the pic http://www.diystompboxes.com/smfforum/index.php?topic=36392.msg602428#msg602428

definitely gonna try the "repeat clipping" mod.

andrew_k

Quote from: slacker on February 10, 2009, 01:14:54 PM
With the bleed through does it stop if you turn the level all the way down? If it does then it might be worth trying a different CD4066 to see if there's a problem with yours.

It only happened when I was using another effect in front of it; in this case a Subdecay Prometheus. I can't make it happen when it's just guitar > echobase. I don't think I have any more CD4066 on hand but I will try the level control test after work and report back.

Oh and Ian, thank you so much for the all your work supporting this effect. Designing and releasing it is one thing, but 24 pages of helping people build them is another thing entirely.  :)

fhsueh

Quote from: slacker on February 09, 2009, 12:46:37 PM
I take it the dry sound is fine, which means the problem isn't with the opamp input and output buffers.
A couple of people have mentioned problems with humbuckers, unfortunately none of my guitars had hot pickups when I built it so it wasn't ever a problem for me.

I can think of a couple of things that could be causing it.
1. If your signal is hot enough it could be causing the diodes in the feedback loop to clip, especially at higher feedback levels. Try removing the diodes connected to the feedback pot and see if that solves it. If it does then either leave them out completely, or try replacing them with 2 diodes in series each way, or even LEDs. The only downside to doing this is that the self oscillation will be louder, which may or may not be a problem  :icon_twisted:

2. The opamp stages in the PT2399 might have too much gain. You can reduce this by reducing the size of the 47k resistors attached to pins 14 and 15. Try temporarily putting another 47k in parallel with one or both of them and see if that solves the problem. If it does then replace them with 20k - 30k resistors, you might find the tone of the delay changes a bit doing this, but if it solve the clipping problem, I'll figure out how to change the caps in those stages to get the tone the same.
It might also reduce the volume too much for you, but you can probably get that back by decreasing the size of the 10k that follows the level pot.

Unfortunately, removing the diodes didn't eliminate the distortion for me.

Is there a way to try #2 above without having to dismantle my wiring (to turn over the pcb), and without having to actually remove the existing resistors?


slacker

Quote from: andrew_k on February 10, 2009, 05:24:49 PM
Oh and Ian, thank you so much for the all your work supporting this effect. Designing and releasing it is one thing, but 24 pages of helping people build them is another thing entirely.  :)

Thanks Andrew, appreciate it.

I figure people have spent a  fair amount of time, money and effort building it, so the least I can do is help them out with a bit of debugging.

slacker

Quote from: fhsueh on February 11, 2009, 01:03:13 AM
Is there a way to try #2 above without having to dismantle my wiring (to turn over the pcb), and without having to actually remove the existing resistors?

If you can get to the solder pads or just the exposed leads to the resistors, you should be able to tack another resistor in parallel to them. You  could probably just wedge another resistor in place or even hold a resistor with the leads touching the right places just to test it.

fhsueh

YEAH! I fixed the distorting problem to a very acceptable threshold by adding a 47k each in parallel with the two 47k's off of Pins 14/15 of the PT2399.  This lowered the overall effect level as Ian predicted, and so I put a 4.7k in parallel with the 10k after the Level pot, and this did the trick (it was the only other acceptable value I had available).  Now I have to try Very hard to make it distort. Thanks again, Ian for all the support.  I'm psyched to put this pedal into action finally.

npx

I started building this today, hopefully there won't be too many hiccups along the way!

One question though: I want to add an LED that will flash with the delay time... is there a reasonably simple way of doing this?

Barcode80

Quote from: npx on February 17, 2009, 11:00:44 AM
I started building this today, hopefully there won't be too many hiccups along the way!

One question though: I want to add an LED that will flash with the delay time... is there a reasonably simple way of doing this?
search the thread. it's in there.

andrew_k

Quote from: npx on February 17, 2009, 11:00:44 AM
I started building this today, hopefully there won't be too many hiccups along the way!

One question though: I want to add an LED that will flash with the delay time... is there a reasonably simple way of doing this?

That depends on your definition of reasonably simple


npx

#472
Ahh cool, thanks... I did go through all 24 pages of this thread before I asked that, I must have missed it!

andrew_k

I don't even know if it was posted in this thread. I had it filed away on my computer so I just uploaded it when you asked for it. I didn't design the layout and have never tested it. It was marked as verified in the thread I saved it from.

npx

Yeah, I don't remember seeing it. Looks interesting, but a little more trouble than it's worth... especially since I already have a 2nd pcb for the short/long time mod. I'll keep that pic for a rainy day though!

championdjk

Hello sort of new to the forum.. I really want to build one of these but want to make it true bypass.... can anybody post a vero layout with the 4066 and associated parts removed.... I've built several pedals but I know nothing of theory of electricity just really good at following directions. Any help would be appreciated. Thank You

slacker

Welcome to the forum  :)

The easy way to make it true bypass is just build it stock on my vero layout or the PCB and just leave out the tails switch, the footswitch and the LED, that makes it "always on". Then just wire up your true bypass switch using whatever method you like. That way if you decide to go over to the dark side and experience the joy that is delay tails you can  ;D

If I get time I'll butcher the vero layout to remove the switching.

championdjk

Thanks Slacker :) I can't wait to build this... and would love to see a butchered layout... my order of pt2399's probably will not come for another week ;)

Calamardo

Hello!. I built my echobase but i have a really really bad backgroud noise and i wonder if i fried the 2399, after that i tried the ic in a rebote delay and have the same horrible noise (like a cloud of white noise that not change if i move the pots). I have put 2 wrong value components: 10k instead of 10M in the 4066 and 1n instead of 1uf in the lfo. I measured all the voltages and are close to the posted voltages  ???. Any help will be appreciated.

Pd: I tried a ht8970 delay ic and worked well, but the repeats dont sound good  :icon_cry:

Barcode80

sounds like a fried chip. although i'm surprised your circuit switching works with the resistor you used on the 4066, those two part errors shouldn't make the unit not function properly. i've gotten that white noise from a fried 2399 before.