Echo Base - a new PT2399 delay

[Bucky Weaver]

I am still having 2 weird issues:

A. No matter what speed the settings are set at, I only get one "repeat" or "echo" per note. I am certain I don't have a wiring issue with the "Time" pot, which I double checked multiple times.

B. Also, in the last 15% - 20% of the rotation of the "Level" control, the clock noise starts to bleed through.

Any Ideas?

[slacker]

Hello everybody!!

Welcome to the forum Glad you like the pedal.

Maybe as I use a bigger pot than the one in the scheme could it be the cause?! Infact at that position the depth is too deep... and become a strange funny fx that bends the notes played.

How big is the pot you used?
If you used a much bigger one, that would increase the amount of  modulation like you said. If you want less modulation using the same pot then make the 240k resistor before the pot bigger.

[slacker]

A. No matter what speed the settings are set at, I only get one "repeat" or "echo" per note. I am certain I don't have a wiring issue with the "Time" pot, which I double checked multiple times.

Check the wiring of the feedback pot and the components around there. If you're only getting one repeat that's most likely where the problem is.

B. Also, in the last 15% - 20% of the rotation of the "Level" control, the clock noise starts to bleed through.

Not sure about this, see if you can get everything else working first. Hopefully then it will be Ok.

[prnet]

Hello, here I posted a pic of my new echo base, with some of his friends

http://www.fennecelectronics.it/smf/index.php?topic=1517.msg39920#msg39920

[SimonS]

Hi everybody, After looking at the Echo Base project, I decided to edit it to my taste. I made it true bypass (the tails feature is a very nice idea, but I dont find it necessary for my application), and added a Modulation on/off switch. This is the schematic:


Are there mistakes in this schematic? I hope I removed the boss/tails correctly, and implemented the mod on/off in the correct way. Thanks.

[slacker]

Yes you've removed the tails switching correctly.
The method you've used to switch the modulation on and off will work but you might get some strange noises when it switches. Basically, if the switch breaks before it makes there will momentarily be an infinite resistance between pin 6 and ground which will cause the delay to switch to a very long delay time causing a nasty sounding spike in the signal.

A better way to do it is either to have the switch ground the base of the BC560 or make it short out C5 both of these will kill the modulation cleanly. I prefer to short C5.

By the way welcome to the forum

[German]

Did I need a fixed switch for active bypass, or simple button? SPDT, on/on, not fixed? For schematic on the first page.

[slacker]

For the bypass switch you need a latching SPST switch. Or you can just use half of a SPDT switch, which are probably easier to find.

[moosapotamus]

This pedal is way cool! Thanks, slacker!

For my purposes, I'm replacing the delay level pot with the blend mod that someone very kindly posted earlier in this thread. With the delay level control hardwired for maximum level, the blend control seems to work well enough on it's own, going from totally dry at unity to a good 50/50 mix to a slightly boosted delay.

Something else I came up with for this pedal is an add-on envelope detector for an alternate modulation source. It doesn't play very nicely with the LFO mixed in, but I think it's cool enough on its own to include on a little daughter board and be able to select either LFO or Envelope for the modulation source. Here are some quick clips I made (playing bass... of course!) comparing the LFO to the Envelope detector...

Set 1
LFO modulation source 1 - slow speed
Envelope modulation source 1 - slow attack

Set 2
LFO modulation source 2 - fast speed
Envelope modulation source 2 - fast attack

And for good measure, here's the schematic as it stands for now.



It seems like the Attack control can be set to attack faster than the delay Time. When a short Attack setting is combined with a long delay Time setting, the delay sound seems to get cut off before it gets to the output. Can sound gated and distorted in a very short sputtery kind of way. Was a problem when I was trying to use a 100K pot for the Attack control. But with the 500K pot it seems like it's now possible to find an Attack setting that sounds good at any delay Time setting.

Would be interested in any comments and/or suggestions that folks might have about possible improvements.

~ Charlie

[snap]

dug a little deeper:
http://acapella.harmony-central.com/forums/showthread.php?p=31391466#post31391466
Clari(not)!

[returntable]

Hey moosapotamus, the Envelope Detector Mod is really cool!
I guess I'll have to build another Echo Base, because I'm not able to squeeze another PCB in the enclosure...
But Maybe I just try to make the Stereo/PingPong Version...


The Clari(not) also sounds very cool. Did someone from this Forum build it?

[slacker]

Very cool Charlie, I might have to try that out. Have you tried hooking the output up to the base of the PNP transistor instead or the top of the modulation depth pot instead of to the delay pot, that might give a better effect.

[moosapotamus]

Hi Ian. Yeah, I tried both of those spots and got no action. Tried some other stuff, too. Like driving a vactrol with a transtistor and attaching the LDR leads to pins 4 & 6 of the PT2399. Got nothing with that either. Basically just tried a bunch of stuff until something started sounding good. Again, hats off to you for creating this circuit and posting it for everyone. For my needs, I simply can't get by with a delay pedal that does not allow the tails to play out after you stomp it off. So this is great! Now I just wish I could mod my stereo memory man with a tails switch.

Thanks
~ Charlie

[doug deeper]

yeah the clari(not) is my doing 
i love the echo base!
its the only delay on my board now!
i added a momentary switch as well as the latching so i can just give it a wack and do dub spaceship stuff.
real fun pedal!

[returntable]

yeah the clari(not) is my doing 

cool Pedal!
Wanna share the schematics? or maybe tell us how you did it(similar to the echo base?)
If not that's perfectly fine though

[doug deeper]

well, its just an envelope follower controlling the delay time.
add some fuzz a blend control and whatever you'd like and you'll get pretty close!

[returntable]

Ah okay... so what I imagined was actually pretty close

[Valoosj]

Ian, would it be possible to add a tap tempo switch?

[slacker]

The simple answer is no you can't add tap tempo. It's probably technically possible using a PIC or some other sort of micro controller but as far as I know nobody has done it yet and I certainly don't have the skills to do it, sorry.

[John Lyons]

I have a couple Echo Base boards left if anyone wants one.
They are $14 total including shipping.
Paypal is good for me...just PM or email me.

John