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Greetings all! This is my first time posting for help. Thanks in advance for your generosity and wisdom. This is my third BYOC build. First was 2knob compressor, 2nd was tremolito. I’m experiencing several issues with my newly finished Echo Royal build. I’ve scoured the boards already and cannot find solutions. Here are the symptoms:

1 - In “trails” mode, when I bypass the pedal, I can still hear echoes being created and “leaked” into the signal at about 1/4 the volume of the “active” echoes. They are also distorted. However, this only happens in “trails” mode. In normal bypass mode, no issue.

2 - There seems to be some significant unpleasant distortion on the first echo. It’s independent of delay time, always on the first echo ONLY. Sounds like static or crackly. Subsequent delays are clean. However, it doesn't happen on every note/chord. Seems somewhat dependent on how hard I play. It's very prominent when I play loud chords or "poppy" plucked sounds.

3 - The delay time knob creates it’s own “popping” sound that then echoes out when it’s turned clockwise. This doesn’t happen when it’s turned counterclockwise. only in the one direction.

4 - Not really an issue, but an observation: The delay time at maximum setting is about 2 seconds. Significantly slower than the one in the demo video. Not sure this matters, but thought it might mean something since I saw reference to posts about older chips and delay time/distortions.

I can post pics if it seems necessary from the start. Just lmk. My soldering is pretty clean I believe. I built the other two pedals without issues and they sound great.

Cheers…

Please contact sales@buildyourownclone.com and request a new MCU.

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*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

...and tell 'em Keith sent you!!

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My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Will do! Thanks so much. What does the MCU do that could be responsible for these symptoms?

The MCU controls everything that is involved with switching and delay time. That seems to be where all you problems are. There are some analog components involved in all those functions, so it's possible that it's not the MCU, but I figured it would be easiest to rule out the MCU before having you do a lot of other diagnostics and posting pics. Hopefully, you'll plug in the new MCU and everything will be good.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Update: I received the new MCU chip (THANK YOU!) and unfortunately it made no difference whatsoever in the symptoms mentioned at the top. While I had the pedal open, I decided to swap the PT2399 chips to see if anything would change. It did not effect the tone of the repeats at all (distortion wise), but now when I'm in trails mode and I bypass, the "leaking" repeats only happen for a few seconds and then it seems to be bypassing normally. So, with the PT2399 chips in their original configuration, bypass in trails mode would not work and I could still hear quiet distorted repeats for as long as I continued to play. Now with delay chips reversed, the distorted repeats in bypass mode only last for a few seconds and then it's quiet. Not sure if this helps at all. Sounds like I'll need to get the board out and send pics, eh?

I'm sort of having some trouble understanding your symptoms. Is it easy for you to post a quick video of the issues to youtube or something? That often helps quite a bit.

On the distortion on the 1st repeat - it could be something to do with the compander chip, but it could also be PT2399 issues. The PT2399s need to have 5 volts DC on pin 1. Lower voltages will cause all sorts of issues. If you can, check to see if you have 5 volts at pin 1 of both PT2399s.

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

Hey Morgan, Thanks for the info. This evening I sat down and listened to the Echo Royal Demo video with headphones and I'm beginning to think that the distortion I was hearing may just be part of the character of the pedal. I'm hearing similar distortion on the demo. The bigger issue is the fact that the bypass doesn't bypass in trails mode. I will test the voltages as suggested as soon as I get some alligator clip leads so I can hook the power supply back up. I had to desolder the jack to remove the PCB. I'll do some more investigating then. Let me just ask, is it anything unusual that my max delay time is 2 seconds? On the demo video he states that the max is 1.5 seconds, but it sounds like much less than that. I don't mind it, but wonder why the huge discrepancy.

Anyways, thanks for the input. I'll get back with more details when I can test voltages easier.... You guys have been very responsive and helpful. Much appreciated.

I am wondering about that. There are a few things to know about the delay time:

- The PT2399 delay chips are digital echo chips. The delay time is set by resistance to ground on pin 6, which sets a certain voltage. 50k to ground gives you about 600ms of delay time and that is sort of the standard size delay pot we typically use for these chips (50k). The delay pot typically sits between pin 6 and ground.
- Echo Royal does not use a delay pot between pin 6 and ground, but instead uses the MCU and MCP chips to set the delay time voltage using the delay time pot or tap tempo.
- Echo Royal uses 2 PT2399s in series to double the delay time.
- As you increase the delay time on these chips, they become noisier with digital artifacts becoming apparent on the delays. You can actually push the delay time for each chip much farther than 600ms, but the signal begins to degrade quite a bit (but only degrades on the longest repeats.
- With everything functioning correctly, the maximum delay time would be whatever the MCU/MCP sets it for in this pedal.
- Echo Royal also puts a compander chip in the circuit to control delay chip noise and to make it sound more like a traditional analog delay. That is likely the distortion you're hearing on the 1st repeat.

So, perhaps, maybe something is off here and the delay time is being shifted to the long side. You can try measuring resistance from pin 6 to ground when the delay time is set for the longest, but I don't know if that will actually work with the MCU/MCP in the equation.

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

Does anyone have specs on what the voltages should be at each pin of each chip? I could probe them all if that is useful info. I'll start with the pin 1 on each delay chip as suggested.

OK. So I tested the voltage at pin 1 of both delay chips and I get 5.05 V at both. Not sure what else would be worth testing. I'll take any suggestions!

Here's a link to a video I made so that you can hear the bypassing issue and some of the distortion.

https://youtu.be/39MZ6jqKBw8

Thanks - that helps.

As to the distortion, it sounds like it is working fine to me. You're not going to get super clean repeats out of this circuit. The PT2399s have their own grainy character and the compander also adds a bit of grain. Traditionally, delay is mixed a bit lower than what you have in the video, and as you dial back the wet signal in the mix, the distortion is not so apparent.

The trails switching is a bit complicated. The MCU does the swiching by changing the voltage between 0 and 5 volts at points A, B, and C on the schematic. The voltage either 'opens' or 'closes' the switching jFETs Q5-Q8. 0 voltage closes the jFET by creating a high resistance, and applying 5 volts opens the jFET, creating an open connection.

Check out the voltages at A (MCU pin5), B (MCU pin 3), and C (MCU pin 7). Make sure you're measuring the correct pins. Here's what you should have:

Bypass (non trails) A = 0, B = 0, C = 5

Bypass (trails) A = 0, B = 5, C = 5

Effect mode A = 5, B = 5, C = 0

If those voltages seems fine, follow up by checking the voltages at diodes D1-D4. Power the pedal and measure the voltage at bypass and effect mode. The striped side will go 0 to a little less than 5 volts; the non-striped side will go very slightly negative voltage to very slightly positive (we're talking hundredths of volts, DC).

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

What I suspect is happening is that one of the jFETs is not closing in trials mode, allowing signal into the wet signal path.

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

OK. Here are the voltage results as per your suggestions Morgon:

Bypass - A=0, B=0, C=5
Bypass (trails) - A=0, B=5, C=5
Effect mode - A=5, B=5, C=0

So that looks good....

Diode____________________D1 D2 D3 D4
Bypass stripe______________1.2mV 1.2mV 1.3mV 2.53V
Bypass non-stripe_________0 0 0 3.3mV
Bypass trails stripe________1.3mV 0 2.53V 2.53V
Bypass trails non-stripe___0 0 3.8mV 3.6mV
Effect mode stripe_________2.52V 2.52V 2.52V 1.5mV
Effect mode non-stripe____3.1mV 3.4mV 3.8mV 0

Should D4 also have some significant voltage in effect mode? I didn't see any slightly negative values, but I suppose zero could effectively be that. I don't know how precise my meter is at these tiny voltages.

Thanks again for all the help!

Do you see anything here that leads to ideas?

Sorry, I now realize that spaces don't hold when you post. I had the values arranged as a table. The 4 values for each setting (e.g. "bypass stripe") apply to D1-D4 respectively. If you need me to clarify, lmk.

When you get the wet signal leaking through in trials bypass, is the volume of the wet signal affected by the mix pot?

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

Yes. The mix pot affects the volume of the leaking repeats.

Here's another observation. When I first turned the pedal on and bypassed in trails mode, I only got "leaking" delays for a second or two and then it was properly bypassing. I turned effect mode back on, then off again, and now the leaking delays continue indefinitely. Almost like something needs to "warm up" first, or maybe charge a little before the leaking really takes hold. I've observed this before as well.

Check out Q5 and Q8. make sure they are 2N5457 (or 2N5458, J111, J112, J113) and you didn't swap in a 2N3904 or 2SK246 by mistake.

If they are the correct jFETs, reflow the solder joints on them again. If that doesn't do anything, I would consider replacing them.

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

I confirmed that Q5 and Q8 are J112s and I reflowed the solder joints. Unfortunately no change. I'll find some new replacements. Does it matter if I replace them with 2N5457s? Shouldn't matter, right? I'll get back when I've replaced them.

On a separate note, I also have an issue with the delay time pot crackling and popping as it's turned UP. When I turn it down, no issue. Here's a link to a video so y'all can hear it. Is this a problem with the pot, or somewhere else in the circuit?

https://youtu.be/Q3zx3P0kFH8

Once again, thanks so much! I'm really looking forward to getting to use the pedal.

Right - they are just used for switching


That's odd. I'm tempted to tell you to punt it until the bypass issue is resolved. I wonder if it's a loose connection on one of the wires? Can you get it to pop if you vigarously wiggle any of the wires attached to the pot? Maybe the pot has some smutz inside. Do you have contact cleaner to clean the pot?

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

Hey all. I finally found the time to replace Q5 and Q8 as suggested and the leaking repeats are gone! Looks like that did the trick. Thanks for all the support Morgan.

The delay pot still pops when turned up, but for now I'm going to spend a little time with the pedal before I go declaring any other issues.

Thanks!!!