Spatialist reverb issue

[jrh312]

I put together the Spatialist (FV1 soldered on by PedalPCB) but am having issues. More doesn't work than does work.

1. Volume pot is functioning backwards....full left is max volume.

2. Mix pot acts as volume also, so I m assuming "max volume" on the mix pot is actually a full dry signal and "no volume" is full wet.

3. Top 3 pots do nothing at all.

4. Rotary switch causes no change, but I can hear a dull thud when I switch it. Causes no change to the sound and all sound just like it's bypassed.

I also included a screenshot of the oscillating crystal I'm using because I had some on hand. It's the same frequency as the one in the BOM but I got it from Tayda so it might not be an exact match. Wondering if that might be the issue because it seems like the FV1 is not functioning as it should.

 

[jrh312]

So here's a thought..... The website shows a picture of a 24LC32a EEPROM, which is what the schematic and BOM call for. Mine very clearly has 24LC64 printed on it. Any chance those two are not a direct replacement for one another? I wonder if they sent me the wrong chip.

Nevermind. Further digging around and it's just a different amount of memory. They should be compatible.

If I want to try to bridge those two rotary pins to their appropriate next components, I think I have it narrowed down a bit. Based on an old post I found by Robert, I think those pins are 5 and 6. It seems to me that even if I pulled those pads, modes 1 and 3 would still work because the schematic doesn't seem to show overlap with 5 and 6 there, but I may not be interpreting it right.

Regardless, could I try bridging rotary pin 5 to R17 to see if the pad is lifted?

 

[PJS]

If you are worried about the mode switch test it's function first. You have the internal sounds working. The mode switch will switch through them the same way as it switches through the external ones. If you don't get the correct sounds in the correct order then the switch will be the problem. They should be:

ROM Programs
The FV-1 includes 8 programs in the internal ROM, these programs and the assigned potentiometer input controls are detailed in Table 1.

Table 1 - ROM Programs
Prg # Description POT0 POT1 POT2
0 Chorus-reverb Reverb mix Chorus rate Chorus mix
1 Flange-reverb Reverb mix Flange rate Flange mix
2 Tremolo-reverb Reverb mix Tremolo rate Tremolo mix
3 Pitch shift Pitch +/-4 semitones - -
4 Pitch-echo Pitch shift Echo delay Echo mix
5 Test - - -
6 Reverb 1 Reverb time HF filter LF filter
7 Reverb 2 Reverb time HF filter LF filter

 

[jrh312]

If you are worried about the mode switch test it's function first. You have the internal sounds working. The mode switch will switch through them the same way as it switches through the external ones. If you don't get the correct sounds in the correct order then the switch will be the problem. They should be:

ROM Programs
The FV-1 includes 8 programs in the internal ROM, these programs and the assigned potentiometer input controls are detailed in Table 1.

Table 1 - ROM Programs
Prg # Description POT0 POT1 POT2
0 Chorus-reverb Reverb mix Chorus rate Chorus mix
1 Flange-reverb Reverb mix Flange rate Flange mix
2 Tremolo-reverb Reverb mix Tremolo rate Tremolo mix
3 Pitch shift Pitch +/-4 semitones - -
4 Pitch-echo Pitch shift Echo delay Echo mix
5 Test - - -
6 Reverb 1 Reverb time HF filter LF filter
7 Reverb 2 Reverb time HF filter LF filter

I will give that a shot tonight, thanks! That R5 leg is still grounded, FYI. Should be fine right?

I had somebody else suggest testing the FV1 default modes by removing the EEPROM completely from its socket. The grounded R5 should achieve the same thing though if I'm understanding it right.

 

[Cybercow]

I will give that a shot tonight, thanks! That R5 leg is still grounded, FYI. Should be fine right?

I had somebody else suggest testing the FV1 default modes by removing the EEPROM completely from its socket. The grounded R5 should achieve the same thing though if I'm understanding it right.

Just removing the EEPROM will NOT instantiate the internal sounds from the FV-1. Grounding R5 is the way to set the FV-1 to use its internal sounds. BUT . . . it's vital that the pin 13 side of R5 be grounded - not the other side. Shunting the other side of R5 to ground might damage the 3.3V regulator.

A 24LC64 is NOT a proper replacement for the 24LC32A as they store the data in different sized increments. I have no clue if the 24LC64 would even work or even load the data for FV-1 patches.

 

[jrh312]

Just removing the EEPROM will NOT instantiate the internal sounds from the FV-1. Grounding R5 is the way to set the FV-1 to use its internal sounds. BUT . . . it's vital that the pin 13 side of R5 be grounded - not the other side. Shunting the other side of R5 to ground might damage the 3.3V regulator.

A 24LC64 is NOT a proper replacement for the 24LC32A as they store the data in different sized increments. I have no clue if the 24LC64 would even work or even load the data for FV-1 patches.

Interesting.... I will get ahold of them tomorrow. Maybe it's as simple as they sent me the wrong thing.

Also, I feel like a moron asking so many little questions but I'm out of my depth here.... So here's another.

Last night when I grounded R5, I removed the leg that had continuity with the 3.3v. from your description above, it almost sounds like you're saying I need to switch which leg I have grounded..... In other words ground the one that's got continuity with the FV1. Is that correct?

 

[jrh312]

I don't suppose you happen to have another FV-1 based board or pedal lying around? If so you can swap the EEPROM in and see what happens - to test a new EEPROM you will need to have R5 connected to 3.3V again. Personally on my Arachnid build once I lifted R5 I soldered it to a switch with 0v and 3.3v on the switch so I can access the internal programs or EEPROM programs at will

Now that I see what the FV1 internal programs are, I see the benefit of what you're saying here. I like this idea of installing a switch a lot actually. Just a simple SPDT, right? If I can get this thing to work I might steal your idea lol

 

[Robert]

A 24LC64 is NOT a proper replacement for the 24LC32A as they store the data in different sized increments. I have no clue if the 24LC64 would even work or even load the data for FV-1 patches.

Yep, 24LC64 is compatible and works perfectly fine.

That's what we're using at the moment since 24LC32A is unavailable due to the semiconductor shortage. They cost more, but at least they're available.

 

[Robert]

In other words ground the one that's got continuity with the FV1. Is that correct?

Correct. You're actually grounding pin 13 of the FV-1 IC, but the resistor is an easier spot to solder a jumper onto than the SMD pin of the FV-1 IC itself.

If this gives you an effected signal we can assume the EEPROM is the culprit, just let me know and I'll get a replacement out to you.

(Shoot me an email, I might miss your post here)

 

[jrh312]

Correct. You're actually grounding pin 13 of the FV-1 IC, but the resistor is an easier spot to solder a jumper onto than the SMD pin of the FV-1 IC itself.

If this gives you an effected signal we can assume the EEPROM is the culprit, just let me know and I'll get a replacement out to you.

(Shoot me an email, I might miss your post here)

Will do. You can probably ignore the email I already sent earlier today asking if the 64 is a replacement for the 32 haha

Thanks!

 

[Robert]

Will do. You can probably ignore the email I already sent earlier today asking if the 64 is a replacement for the 32 haha

Already replied to confirm your address. I thought that must have been you.

 

[jrh312]

Already replied to confirm your address. I thought that must have been you.

Ah, yeah I do see that there now. Yeah still the same address. I'll let you know tomorrow after work one way or another.

I still keep going back to the possibility that I may have lifted those two pads when I flipped the rotary switch to the other side. What can I expect to see if I ground pin 13 and the switch conductivity actually is the issue (in the event that a pad is lifted)? Should the other programs still work?

 

[Robert]

If you had lifted pads to the rotary switch you would still have an effect, the rotary just wouldn't change programs correctly.

If you have an effected signal when you ground pin 13 we can assume the EEPROM is the problem, regardless of how the rotary switch behaves.

You can, however, at that time switch through all eight positions and check to see if you get a different effect for each position to test your rotary switch.

 

[PJS]

Pins 16-18 of the FV-1 should also measure a different combination of voltages with every different position of the rotary switch (will count up in binary). Each effect position should have an audible difference though if you are listening rather than measuring voltages.

 

[Cybercow]

Yep, 24LC64 is compatible and works perfectly fine.

That's what we're using at the moment since 24LC32A is unavailable due to the semiconductor shortage. They cost more, but at least they're available.

Thanks for that Robert. I had no idea they would interchangeable like that with the FV-1.

 

[jrh312]

i've edited this a couple of times now. Making progress.

grounding pin 13 gives me effected audio at Pin 28 when probed. The rotary works, and the upper pots do as intended (vol and mix pots don't but it looks like that would be expected).

points to a faulty EEPROM then, right?

 

[PJS]

It's either a faulty EEPROM or the connections from teh FV-1 to the EEPROM

Mix and vol should indeed be working as expected with the internal programs. If they are not then that is a problem, but a separate problem

 

[jrh312]

It's either a faulty EEPROM or the connections from teh FV-1 to the EEPROM

Mix and vol should indeed be working as expected with the internal programs. If they are not then that is a problem, but a separate problem

I should clarify the vol/mix pots dont do anything when I'm probing pin 28, which makes sense because I'm moving the output up before where they would be. Maybe I'm totally wrong though haha

They do work if I probe the output pad so they're good. If I have the output wire in place, there's no audio on it, but if I take it out of the board I get audio on the pad.

Pretty sure that means I have a bridge or a stray wire strand on the switch. Going to look into it tonight but I'm just about there I think.

 

[PJS]

That is indeed promising

 

[jrh312]

That is indeed promising

I think so yeah. I ended up resoldering several things on the switch and am getting audio through the output wire now like I should be.

Being satisfied with that, I did resolder the one resistor, which put pin 13 of the FV1 back to 3.3v instead of ground. This brings me back to getting no audio, including when probing at FV1 pin 28. I feel better that it's just the EEPROM now, based on what you guys have said.

Once I get that replaced I think I'll be good to go. I'll post an update when I swap it out, but in the meantime thank you to everybody who has helped me with this. This was a different type of build than I've ever done, so lots of new territory covered for sure.

 

[Sparky_mark]

Did you ever figure out what was wrong? I am having the same issue and could use some help!