Equinox: Easy PT2399 Reverb

[theundeadelvis]

You can just paste it in the address bar without the www. part (just start with freewebs.com). It will redirect to the appropriate address. Works fine for me in Chrome and Firefox

[waltk]

With Merlin's permission and assistance, I made a PDF with all the files related to the Equinox.  It has high-resolution images of the schematic, layout, and PCB transfer.  The PCB transfer image is actual size.  There's also a bill of materials included.  The PDF is hosted here in the DIYStompboxes gallery - so it shouldn't disappear.

Here's the download link: http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=46248&g2_GALLERYSID=74c3a65f5fc52fdecfa64fec06407a15

[askwho69]

this is a reverb that i was looking for opps found!

Thanks so much

[John Lyons]

Thanks for the rehost Walt, cool circuit Merlin.
Thanks for sharing!

[Mark Hammer]

I etched and drilled two boards last night, and am looking forward to stuffing them and firing them up.  We have a government-wide charity drive for the United Way every year at this time, and in years past I've contributed a pedal to the fundraising auction.  This year's contribution will be an Equinox, with whatever additional bells and whistles I can stuff into a 125-C.

Thanks. 

[meffcio]

With Merlin's permission and assistance, I made a PDF with all the files related to the Equinox.  It has high-resolution images of the schematic, layout, and PCB transfer.  The PCB transfer image is actual size.  There's also a bill of materials included.  The PDF is hosted here in the DIYStompboxes gallery - so it shouldn't disappear.

Here's the download link: http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=46248&g2_GALLERYSID=74c3a65f5fc52fdecfa64fec06407a15

Great, I was waiting for that. For this kind of reverb, AND for the pdf. Since I have some pt's, I'll build this guy soon, and see for myself what is it capable off.
But to be honest - vectorized pcb in the pdf would be much better (loseless). Isn't the tracing software capable of exporting the board directly to the pdf?

[merlinb]

Isn't the tracing software capable of exporting the board directly to the pdf?

Good question. I'll have to double check that...

[dam28]

Quick question: What's the point of transistor Q1? Am I right in thinking the output from the first opamp feeds into the input of the first PT? I just don't understand Q1.

Cheers!
D

[merlinb]

Quick question: What's the point of transistor Q1? Am I right in thinking the output from the first opamp feeds into the input of the first PT? I just don't understand Q1.

Q1 in an analog switch. When the base is pulled low the transistor switches off, and no signal is passed to the delay line. This is how bypass with tails is achieved. You could also use a FET in this position, if the base resistor is replaced with a diode, which might look more familiar to you?

[dam28]

Interesting. So it's simply the bypass on the circuit? I could just feed the output of the op-amp into the input of the PT?

[merlinb]

Interesting. So it's simply the bypass on the circuit? I could just feed the output of the op-amp into the input of the PT?

Yes you could replace Q1 with a direct link, if you are using true bypass or something.

[Paradigm X]

Hi, thanks for posting this, I have 5 pt2399s and been looking for a reverb, perfect!

Minro query (bit of a noob, sorry), would this require any modification for use as line level (synths etc)?

Cheers,

Ben

[therecordingart]

If anyone is planning on etching a board...etch an extra and I'll buy it off of you.

[dam28]

Cheers for the advice Merlin!

[merlinb]

Minro query (bit of a noob, sorry), would this require any modification for use as line level (synths etc)?

The delay line will handle 2Vp-p signals as it is. If you want it to handle larger signals then you would need to reduce R11 and increase R19 proportionately.

[Paradigm X]

Minro query (bit of a noob, sorry), would this require any modification for use as line level (synths etc)?

The delay line will handle 2Vp-p signals as it is. If you want it to handle larger signals then you would need to reduce R11 and increase R19 proportionately.

Thank-you.


If anyone in the UK (or elsewhere TBH) is making a PCB and can possibly make an additional one I'd be happy to compensate for materials, time and postage.
Many thanks!

Ben

[asatbluesboy]

Baaaaaabyyyyy... Baby, baby, I am gonna leave yo-ou... I ain't joking, woman--I've got to ramble.

Awesome song from an awesome band. I can't recall any band having ever recorded such a perfect first album (ok, it's not the first since they were technically "The New Yardbirds", but anyways...).

Need. To. Build. One. Much more practical than hauling that AC-fed bitch Microverb II around.

[dam28]

Another quick question. R19 and C13 make up the feedback. When I don't connect these I just get two delays, as expected, when I connect the feedback though the circuit goes into crazy oscillation. This is expected also I guess but wonder if you know how to over come this? Get a the reverb to fade out gradually and not go mental!

Good build though. Really enjoying the design.

D

[merlinb]

Another quick question. R19 and C13 make up the feedback. When I don't connect these I just get two delays, as expected, when I connect the feedback though the circuit goes into crazy oscillation. This is expected also I guess but wonder if you know how to over come this? Get a the reverb to fade out gradually and not go mental!

It shouldn't oscillate... sure you haven't made a mistake somewhere? Did you change R11 maybe?
Anyway, quick answer is increase R19 until it stops oscillating.

[dam28]

I'll give this a go later. It sounds quite cool but its a bit hard to control! Ill check my layout and keep you updated. Thanks again.

D