Equinox: Easy PT2399 Reverb

[sajy_ho]

Ok so someone is probably gonna slap me for this but since you guys know stuff at the drop of a hat I thought I'd ask before I read through all the pages of responses on this one.... the parts list shows C10 and C32 as NP (non polar) but the blue/black/pink layout clearly shows + symbol for each of those pieces...so who do I believe? The schematic doesn't quite clear it up for me either (though they are my weak point for sure).

If you've got NP caps around use them for the best results. If you're using electrolytic caps just pay attention to the schematic polarization.
I used both with the same results to my ears!

[Canucker]

Thanks for the info. I'm actually getting no results. I was getting a faint signal in the on or off position and it sounded like there was some effect on it....then I checked everything over and found the solder for my LED was a bit sloppy...obvious place to look since the LED wasn't turning on.....fixed that up and the LED lights up like a Christmas Tree....but now I get no sound no matter what position I have anything....I'm thinking my on off switch is the obvious place to start....I really hadn't looked at this project since last summer when I made it, had no luck and moved on to other stuff quickly as I had a few projects on the go and the others all worked out fine. Thanks!

[garcho]

Many schematics will still show a '+' even if the capacitor is non-polar. If the author of the schematic specifically calls for NP, I'd use those, unless you know why not to. They might sound the same but they might not act the same.

[sajy_ho]

Thanks for the info. I'm actually getting no results. I was getting a faint signal in the on or off position and it sounded like there was some effect on it....then I checked everything over and found the solder for my LED was a bit sloppy...obvious place to look since the LED wasn't turning on.....fixed that up and the LED lights up like a Christmas Tree....but now I get no sound no matter what position I have anything....I'm thinking my on off switch is the obvious place to start....I really hadn't looked at this project since last summer when I made it, had no luck and moved on to other stuff quickly as I had a few projects on the go and the others all worked out fine. Thanks!

I had the same problem with my switch and even after fixing that, there was a little sinal bleeding through that FET. I used a DPDT On/On foot switch that connects R9 to pin7 of TL072 and LED to +V at the same time... problem solved!
And I think garcho is right, better to use NP caps in this case.

[garcho]

^ very general rule: electrolytic caps are for DC (power supply), non-polar are for AC (audio signal).

[merlinb]

Since the non-polar electro caps seemed to be a cause for confusion (why?) I removed them from the latest version by switching to 1uF caps. You can easily get those in plastic or ceramic:
http://valvewizard.co.uk/equinox.html

[deevar]

Greetings to all !

Just finished Equinox II, sounds great, works great, thanks @merlin :-)
I have two questions (Not problems) :

1. Should i lower voltage a bit, since i'm measuring 5.05V between pins 1 and 3 on PT2399, and i read somewhere on this thread that lover voltage keeps PT more stable(fixes possible bad behavior) ?

2. In equinoxII.PDF    pot is labeled just 10K(linear probably), but in schematic on your website it says 10K log. Which one is correct?  I'm using 10K linear

And some pictures:

Changed layout a little - nothing special just removed some ground pour and add more space between few traces and pads... A little easier for me to solder and not worrying to accidentally make some bridges ...

https://www.dropbox.com/s/s2zz3edbhkbkht7/1.jpg

Not yet in a box (waiting for paint to dry)

https://www.dropbox.com/s/4sd4ebkkt6x4bp9/2.jpg


Edit: i used [img] tag but obviously i'm doing something wrong, so pictures not showing, i added links to my dropbox

[merlinb]

1. Should i lower voltage a bit, since i'm measuring 5.05V between pins 1 and 3 on PT2399,

No, 5V is correct. The Equinox does not have the same latch-up problems as some short-delay designs.

2. In equinoxII.PDF    pot is labeled just 10K(linear probably), but in schematic on your website it says 10K log. Which one is correct?

It doesn't matter. I used log in my last build, but the range of control seems to be just as usable with a linear pot.

[deevar]

OK thanks @merlin !
I have to say i like it a lot, already found favorite spot, somewhere around 1-2 o'clock.. 

[fatecasino]

well, I have been trying to make my equinox I work for more than 30 hours!
I have passed through all the phases described here (no sound at all, bypass/effect sound the same, etc)

1. Now it works except one little thing.

• when the fat switch is on, the reverb sounds perfectly.
  when the fat switch is off, the reverb disappears and it actually sounds as if the pedal is bypassed!!

any ideas??

2. Is there a way to make it sound completely wet? How could I give more volume to the effect than to the actual signal?

Cheers!

[merlinb]

when the fat switch is off, the reverb disappears and it actually sounds as if the pedal is bypassed!![/li]
[li][/li]
[/list]
any ideas??

Sounds like you wired up something incorrectly. Can't really be more help than that 

2. Is there a way to make it sound completely wet? How could I give more volume to the effect than to the actual signal?

You can't get rid of the dra altogether unless you removed R4. I guess you could switch it out? You can, however, make the wet sound louder than the dry sound by reducing R5 (not less than 1k though). You might then need to reduce R6 to bring the overall volume down. The Equinox wasn't really designed for that level of control.
http://i81.photobucket.com/albums/j207/merlinblencowe/Equinox%20Reverb/reverbschem.jpg

[Jdansti]

This might not be it, but worth checking. Make sure the switch is wired correctly as shown below. You found also remove the switch and use a temporary jumper to test the circuit.

[fatecasino]

You can, however, make the wet sound louder than the dry sound by reducing R5 (not less than 1k though). You might then need to reduce R6 to bring the overall volume down. The Equinox wasn't really designed for that level of control.

I studied Equinox II and I realized that this project was meant to be a one-knob-pedal. On the other hand, I busk around, so for me it's optimum if I can get the maximum out of just one or two pedals )

I would like to have some really wet/atmospheric reverb, which will have the direct signal somehow lost in the effect. I reduced R5 to 1k and it is still more or less the same feel like  before. Could you imagine a way to turn the direct signal volume even lower?
Thanks!!

[merlinb]

Could you imagine a way to turn the direct signal volume even lower?

Increase R4. If you remove it altogether (infinite ohms) it will turn off the dry signal altogether!

[fatecasino]

i have everything working right now
there is one strange thing though with the PT2399s.
If i turn off the pedal, then at restart i have no delays/echoes at all. To make it work I have to remove (with the power on) the PT2399s and place them back!
At the beginning I had only one PT2399 not sounding at the restart. Now they both have this strange problem, did I burn them somehow?
Any suggestions?


PS: the only not normal behaviour is that when the fat switch is off, I only hear the direct signal. Could it be something with the BC337?

[tommycataus]

I'd just like to say thanks for all your help and your fantastic designs Merlin. Now that I've built the Equinox II I'll soon be tackling the Engineer's Thumb. This has been a good week for me!

I'm not much good with aesthetics but here's what mine looks like:



You're a true gentleman.

Also for the record I agree with deevar, 1-2 o'clock is my favourite. Also I used two non-polarised 1uf caps in mine.

Cheers!

[Cozybuilder]

I wonder if this thread will revive? I've been on a 1590LB binge lately, here is the Equinox II, it sounds great! Thanks for a nice alternative to the Belden brick builds, with the added advantage of being able to fit it into a small box. The voltage regulator is epoxied to the lid. After completing it I realized I had used the wrong name  Sorry Merlin.

Face shot:

[thomasha]

And I thought that my solstice layout was small...
it wass even double-sided, but that is an amazing job!

I had this idea of making the solstice/reverb switch, something like parallel/series...

maybe someday.

Nice small pedal!
Thomas

[bluebunny]

Ah, the wonders of PhotoShop...  


(Hmm...  "Cozybuilder".  Not a coincidence, methinks!)

[merlinb]

I wonder if this thread will revive? I've been on a 1590LB binge lately, here is the Equinox II, it sounds great! Thanks for a nice alternative to the Belden brick builds, with the added advantage of being able to fit it into a small box. The voltage regulator is epoxied to the lid. After completing it I realized I had used the wrong name  Sorry Merlin.

Jesus, that's tiny! Mad skillz. Much respect.