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Forum Home > Layout Gallery - GuitarPCB Build Documents, Mods and Tips > D'Lay v2

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Based on the original DCountry13 Rebote Delay design.

D'Lay Build Document - Latest Update 12/16/14

General improvement by changing R14 to 22k increasing the volume of the repeats or wet signal.

This new design by Bruce R. w/ Special thanks to Tonmann for many of the modifications etc.. incorporated into version 2.

This is based on an Analog Style Delay but with added Delay time of up to 350-400ms,  or slightly longer depending on the quality of the PT2399 chip you use. It is natural for this chip to vary even from the same batch so results will vary as well.

This is an advanced DIY build. - "You should not expect to get 600 ms"


This circuit is moddable to taste but results will vary depending on any number of factors.

While we offer support you must be able to do your own troubleshooting.

This is not a beginner build.

For the intermediate - experienced it should be quite fun and a great learning experience.




This will fit into a 125B enclosure.

If you add mods or the separately available Tap Tempo board  a larger enclosure is needed.   Build Instructions


Dimensions are approximate 2.00" x 1.80"

Check the Forum for answers to many questions before posting a troubleshoot thread.

Do not miss the Easy Pedal Wiring Guide.

Namely the expansive Tips, Tricks and Tutorials section and the consolidated Crash Course Guide.

Please stay tuned to this page as any Mods or potential updates will be placed here.

Tip 1. Solder resistors and 1n4001 in first. Then place, bend and fold Voltage Regulator IC3 before soldering into place being careful of orientation and proper fit lying evenly over the resistors. (See picture below).

Tip 2. Never run audio wires parallel with power wires. Use shielded wire if necessary.

Tip 3. Do not twist your potentiometer wires. Keep them short as possible and straight.

Tip 4. Use Sockets! This allows you to experiment till you find the best match for your build.

Tip 5. When using a 220n or .22uF Capacitor for C1 and C2 please make sure it is a 2.5mm width and not larger or you will need to either socket or extend leads for proper fit. 2.5mm are readily available. Check Datasheets.


Mod 1.

Resistor R-A and TR1 (which was fixed resistor R-B) determine the sensitivity of the Repeats pot. The Alpha pots most people use in their pedals have a 20% tolerance, so a trimmer makes the most sense. You may or may not want to have the Repeats knob to provide infinite repeats at full rotation, but the trimmer can be set to adjust to “just shy of infinite repeats” or “just to the point of infinite repeats”. The Tonepad Rebote delay, from which this circuit was based and modified, calls for a 15k of resistance before the Repeats pot, and calls for 10k to allow infinite repeats. We recommend that you use a 3k3 resistor for “R-A” and a 10k trimmer for TR1. If your repeats pot measures higher or lower than the 50k (between lugs 1 and 3), you may need to increase or decrease the R-A fixed resistor to allow your trimmer to give you the desired repeats.


MOD 2.

The “WF” pad is for the “Warmoth Fanatic” Warp modification. This requires installation of a momentary SPST stomp switch that will produce infinite repeats as long as it is depressed. To implement this mod, you will connect one lug of the switch to the “WF” pad, and solder the other lug to pin 1 of TR1. When depressed, the switch bypasses the resistance of TR1 and allows the repeats to run away.


R22—The PT2399 delay chip was not really designed to deliver 700ms of delay time, which is what it will be set to do when R22 is at 150k. As you increase the delay time that this chip can deliver, the lower the fidelity of the repeats or create distortion. The results will vary from chip to chip as well. We do not expect that everyone will be able to squeeze 700ms of delay time out of every PT2399 chip. If your repeats sound very low-fi, try decreasing R22 to ~82k, which will deliver higher quality, but less maximum delay time.



For quick alternate effects changes I also personally recommend the simple and easy to use 2 Knob Job board!

Total Mod Cluster when used with Tap Tempo - Courtesy of Wilkie, Pete & friends..... not for the faint of heart.


PT2399—Additional comments: There have been confirmed reports of fake 2399 chips being sold on Ebay. We recommend that you buy these from a reputable dealer. Princeton Technology Corporation (PTC) is the manufacturer. Some of the known fakes say “DTC” but not all of them. If you cannot get 600ms of delay time out of a chip, that does not indicate a fake or knock-off.


Welcome to my informational signature:

See our Home Page for all Guides!

Check the Layout Gallery section of the Forum and find your project before building.

Pre-Build Reading Guides:  Crash Course#1 , Crash Course#2 & Tips, Tricks and Tutorials.

Troubleshoot threads must have pictures and voltages.

All builds are 100% verified. Be sure to use Genuine Transistors and IC's

Any serious builder should have an Audio Probe to diagnose problems quickly.

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January 31, 2013 at 9:03 AM Flag Quote & Reply

Site Owner
Posts: 8793

Finished Build courtesy of CounterfeitGentleman:

And finally, with my trusty Altoids tin momentary switch for the Warmoth Fanatic warp mod (trickier than I expected as I needed to shield the outer ring of the jack from grounding against the enclosure. I got around this by using a layer of clearcoat on the lower portion of the threads and using plastic washers on either side of it).


One from Wilkie 1:

And yest another build by WarriorPoet:


It's Purple!  It sounds great!

Here is a Finished Build Thread for a Combo Pedal version:

Mods: R7 is 12k to supply enough signal to TR1 (10k) for oscillation through R-A (3.3k) using the WF mod pad. :)

Here is a Demo using our Tap Tempo Delay circuit board and Tonegod's chips (see D'Lay Tap Tempo PCB Shop)

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Please note that our support of the Tap Tempo will be limited to our circuit board.

While unlikely if there would be a chip issue you will have to contact Tonegod.

Finished the D'lay pedal today, again with an etched enclosure. Sounds awesome!


Been a LONG time since I've been on the forum, but wanted to share my newest build. Man, what a great sounding delay.  I opted for the tap tempo with modulation and have switches for tempo scale and modulation depth (didn't want the double time switch).  This circuit perhaps more than any other on the site is the most compact and well laid out designs (you cram ALOT of box caps in a small footprint).  Delay tones sit "underneath" lead lines perfectly.  And at maximum delay level it's not an overbearing delay.  This circuit really does feel like an analog delay.  Even some of the signal degradation at longer delay times gives it a nice warm and fuzzy delay tone.  If you don't have one, you need one.

Can't say enough about how well these circuits are made and sound.  Thanks Barry!

Not much of a graphics/decal guy myself, but I may try and come up with something.  But here are the pics.

May 26, 2013 at 2:53 PM Flag Quote & Reply

Posts: 655

To increase the volume of the repeats R14 should be 33K.  I chose 22K and was very happy with the results.  I would recommend you socket R14 and see what works for you.


June 19, 2013 at 9:15 PM Flag Quote & Reply

Site Owner
Posts: 8793

Some questions answered courtesy of Kubikinut:

Let me answer some questions one at a time.


I have an On-Off-On switch called Tempo Scale....what does this do besides change the delay time?



The Tempo Scale switch acts as a delay time "divider". Forget the Double Time switch for a minute - if you set the Tempo Scale switch to 'ground', the chip will drive the PT2399 delay circuit at the same tempo that you tap (or dial in with the knob). Toggling this switch divides the output tempo by a preset fraction (reference the tonegod datasheet for the exact settings). The preset fraction is designed intentionally to match musical subdivisions of the beat (quarter, eight, dotted eight, etc.).



Speed Cycle - I believe this works with the Depth control for phasing/chorus/warble effects



Correct. It is more/less pronounced depending on your depth setting and even your delay time (scale and double time as well!) settings. Electronically what it does is very subtly (or not so subtly in some cases) modulate the output voltage driving the digital potentiometer (which in turn subtly alters the resistance value that the PT2399 chip "sees"). This modulation in resistance varies the current that flows from Pin 6, causing modulated delay tone.



When I tap the tempo switch neither of the LEDs (Tap or center positions) seem to flash the exact time of the echo.



I've had varying success in lining up the LEDs to the "exact" delay time. I say "exact" because there is an inherent delay between the speed of light (LEDs) and the speed of sound (delay output). If I were guessing, some commercial pedals put an intentional delay on the LED output for this reason (conjecture only...). Having said that, the TapTation chip also can suffer from delay time degradation at extreme settings. Has to do with the chips accumulation of "rounding errors" in the mathematical/logical programming. Probably a design limitation of the programming language or the chip itself. Typically, you'll see some sort of crystal circuit that drives that chip at a set frequency that tends to be more accurate at controlling the tempo.



Stupid question: does tapping the tap button override and change a tempo set with the knobs and which position do each of the switches need to be in?



No stupid questions - Yes, tapping overrides the tempo knob (and vice versa). The switches and other knobs don't need to be in any particular setting for this to work properly. The double time/tempo scale switches will still function exactly as with the tempo knob (i.e. double/normal delay time, dotted eigth, etc.).



Last question: Does D1 or D2 (LEDs) go next to the tap button?



You can put it wherever you want - that's the beauty of DIY! I chose to use only one LED output on mine because I didn't want to have to drill another hole (I'm lazy like that...). However, you can choose any configuration that meets your needs. I've seen just about every variation in the examples we have here on the forum.

Disclosure: GuitarPCB is not responsible for the availability of Tap Tempo Chips stock

These are sold by another site. Be sure you have one before ordering.

Courtesy of Tonmann:

More insider details about the D'Lay!

The level pot should be controlling the level of the wet signal while TR2 controls the level of the output (wet + dry) signal.


IC1B is configured as a mixer or summing amplifier.  It adds, or sums, an amount of the dry signal via R12 to the wet signal via R14.

The gain of the dry signal at IC1B is set by the ratio of R13 to R12, with a nominal value for both resistors at 22kΩ the dry signal gain is 1.  To increase the gain for the dry signal the value of R12 is made smaller, to decrease the gain for the dry signal the value of R12 is made larger.

Likewise, the gain of the wet signal at IC1B is set by the ratio of R13 to R14, with a nominal value for both resistors at 22kΩ the wet signal gain is 1. To increase the gain for the wet signal the value of R14 is made smaller, to decrease the gain for the wet signal the value of R14 is made larger.

While the gains for the wet and dry signals can be set independently via R14 and R12 respectively, the overall gain can be set by R13.  If  you leave both R14 and R12 at their nominal values of 22kΩ you can increase the gain for both by making R13 larger or decrease the gain for both by making R13 smaller.

Armed with the above knowledge you should be able to adjust the level of the wet signal by changing the value of R14.

June 8, 2015 at 8:29 PM Flag Quote & Reply

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