Aion's Spectron : no sweeping in the modulation

[idy]

hallelujah

So about the signal on the 358. The signal goes in pin 2, the inverting input. Where it still sounds clean.
It goes through a diode on the feedback loop, so on the output, pin 1, it sounds distorted.
The + input, pin 3, goes to ground (a crazy place to bias it) through a 22k resistor, so you will hear a faint distorted signal there.

If you are talking about the bias pot, I would try removing it... but if it is the way I suggested, 0 resistance would be 9v on the pin 3, I don't believe you... it might be set to 100k, so then you would have (22/100)x9=1.98. Which wold be about right.

About sweep downward: this is always a weird setting, like a ray gun in a sci-fi film or something, the sweep doesn't sound natural usually. Mark Hammer has explained elsewhere why envelope filters sound funny this way without some tinkering. But here you need to fool with attack and decay and intensity to get a good down sweep.

Bandwidth controls how much bass gets to the detector. I don't know how the Spectron switch is setup (I make Meat Spheres.) One setting lets everything through, one cuts out some bass, the other turns the detector off (center off switch?.) It is normal to get a lot more sweeping, especially on low notes, when the switch is on "full."

[matopotato]

Nice to hear you got it sorted! Early Santa this year 
What was the problem in the end?
How did you figure out?
(And how you fixed it unless obvious.)
Will begin with my Spectron once Luna and home made wampler inspired All In Diode Galore distortion are done.

[eh la bas ma]

Nice to hear you got it sorted! Early Santa this year 
What was the problem in the end?
How did you figure out?
(And how you fixed it unless obvious.)
Will begin with my Spectron once Luna and home made wampler inspired All In Diode Galore distortion are done.

Thanks, I probably made a mistake cutting to deep into the board at the trigger pads, or something went wrong with the soldering.
I had to solder a jumper (see reply #17) on the pcb to restaure continuity with C4.

Enjoy your build !

[matopotato]

Thanks/Merci!
 

[matopotato]

EDIT: I see that the intensity and decay jacks are wrong. Will fix, but doubt it is the reason for not functioning.

Hi,
Not sure if I should start a new thread or hope someone finds this one. I'll try here first.
I was hoping not having to end up here, but after just finishing a Spectron today and finding that it works somewhat was quite discouraging.
I cut the bridge and installed the external trigger, but did not test it yet.
The Send Return loop seems to work, but the distortion I put in sounded not very good. Probably due to the pedal not working so the combination is off.
I swapped the red diffused for sensitivity for a bright red. Both shine, but the sensitivity one sometimes is off, or on sometimes drops out during knob turning, but I am guessing it will behave normal if the rest starts working.
The green LEDs light up and are sort of half dimmed most of the time. They do not vary as far as I can see, but mostly they are in the dark so I didn't keep much of an eye on them.
Intensity has no effect. But when I connect expression pedal to it, it did have effect and the pedal as well. But on its own no effect.
Attack no effect
Decay no effect with or without expression pedal
Color a very slight effect depending on second row flips
Sensitivity no effect
Blend seems to work properly
Sweep changes something, when up the Sens LED Brightand the Green LEDs go on brighter than usual. Down and it dims Sens and Greens, almost like bypass but much more quiet.
Bandwidth not much happening. Sometimes a flip changes something but after that nothing
Filter can hear a small crackle when flipped, but not much impact on the pedal effect
Mode does something in Up and Middle, but not much in bottom
Range makes distinct changes

I measured the ICs with stomp on and off. Multimeter shorts at 0.00V. Some values fluctuate slightly between readings.
Stomp off
     IC3 (TL072CP closest to range)      IC1 (TL072CP)        IC2 (LM358P closest to Sweep)
1   4.63                                             4.63                       0.00
2   4.63                                             4.63                       0.00
3   4.62                                             3.93                       0.00
4   0.00                                             0.00                       0.00
5   4.62                                             4.62                       dropping all the time down to 3 area
6   4.63                                             4.62                       5.60
7   4.67                                             4.62                       5.60
8   9.26                                             9.26                       9.25

Stomp on, basically the same values for IC3 and IC1
     IC2 (LM358P closest to Sweep)
1   0.00
2   0.00
3   0.00
4   0.00
5   dropping all the time but from 7 ish down
6   7.26
7   7.28
8   9.25

...and now while writing, I checked to verify and readings differ for IC2...
I guess I will have to trace the whole thing for continuity...

Any help is very much appreciated.

[idy]

Welcome to the meatball clone club.
Once you get those jacks sorted out...

First you need to know how it's supposed to work. I know the Aion docs are good, so read them, but I also recommend the original Meatball docs:
https://www.effectsdatabase.com/model/lovetone/meatball#media
scroll way down to "documents: manual." Must read.

Then you will at least know what those knobs and switches do and what are some normal "testing configurations." Hint: attack lower that decay. Sensitivity and Intensity on max, Bandwidth on full.

I think you are telling us you are using a red clear LED for your indicator and a pair of green clears for your optocouplers? So you can see what is happening. And the greens are not flashing when you play? (In up sweep they start dark and flash when you play, in down sweep the start bright and dim when you play.)

If the external control is making the effect happen then you know the filter is working, just no trigger yet. Most common problem...

[matopotato]

Welcome to the meatball clone club.
Once you get those jacks sorted out...

First you need to know how it's supposed to work. I know the Aion docs are good, so read them, but I also recommend the original Meatball docs:
https://www.effectsdatabase.com/model/lovetone/meatball#media
scroll way down to "documents: manual." Must read.

Then you will at least know what those knobs and switches do and what are some normal "testing configurations." Hint: attack lower that decay. Sensitivity and Intensity on max, Bandwidth on full.

I think you are telling us you are using a red clear LED for your indicator and a pair of green clears for your optocouplers? So you can see what is happening. And the greens are not flashing when you play? (In up sweep they start dark and flash when you play, in down sweep the start bright and dim when you play.)

If the external control is making the effect happen then you know the filter is working, just no trigger yet. Most common problem...

Thanks a lot!
The advantage of having to swap those jacks is that it is now out of the box. So Troubleshooting should be easier. I also swapped the DC jack to an inside mount, which probably says something about my current level of confidence...
DL:ed the meatball manual and will read up on it.
I saw before there were some mention to keep attack lower than decay. I tried with Aion Spectron doc example settings and that had Attack on basically zero (I interpreted the values as "o'clock":s)

Yes red diffused LED for on/off footswitch, and bright red LED for "Sense". This bright one is half-lit or quite full depending on the sweep.
Inside the green LEDs fro optocouplers are either dark/out, or half-dimmed or on the bright side, but there is no variation in their brightness when I play. So no flashing, Only change brightness when I flip some of the switches (not tested in any organized way. Yet. Just trying to get some reaction...)
Sweep up they stay dark and in sweep down they stay bright. Makes sense and I understand better how they should work. Thanks.

I needed to rewire the board more to try the external trigger. I have an EQ that splits the signal, that should work for testing.
Or did you mean "external control" as expression pedal?

Will try things tomorrow.
Again thanks for a quick reply. Needed a little bit of a boost.

[idy]

One thing to check is that signal is getting to the trigger, the 358. Your audio needs to get to pin 2. It may sound bad there, but it must get through.

[eh la bas ma]

Good luck with the boxing-unboxing process during the whole debugging journey !

I was reluctant to use the audio probe but, eventually, it was the key to understand what went wrong on my build.

You should try to audio probe the signal path : see reply #12. This method should save you a lot of time. Once you find a spot where the signal stops, the continuity test can come into play to find the problem.

[matopotato]

Good luck with the boxing-unboxing process during the whole debugging journey !

I was reluctant to use the audio probe but, eventually, it was the key to understand what went wrong on my build.

You should try to audio probe the signal path : see reply #12. This method should save you a lot of time. Once you find a spot where the signal stops, the continuity test can come into play to find the problem.

Thanks!
Yes I decided to not box until figured it out.Will build a probe tomorrow an use looper as tone generator.
Although I do have signal. Just not very much varying and some knobs an switches have no effect. Will probe anyway. At least new tool and skill to learn.

[eh la bas ma]

Although I do have signal

I did too, I think the signal goes also in some part of the circuit designed to create the triggering effect.

[matopotato]

One thing to check is that signal is getting to the trigger, the 358. Your audio needs to get to pin 2. It may sound bad there, but it must get through.

Thanks, will probe. Pin 2 was 0V but should probe w signal tomorrow.
It seems Intensity and Sensitivity knobs are swapped on the Spectron vs original Meatball.
Also the Spectron doc mentions "trigger switch" once only, so not sure which one is meant. Or it is a switch internally in the circuit?

[idy]

I think "trigger switch" refers to "bandwidth" which does have an "off" position...although the "side chain mod" does use a switching jack to disconnect the signal from the trigger chip. So two ways to turn the trigger off. Maybe we can get the Aion guy to pipe up about that...

[matopotato]

I think "trigger switch" refers to "bandwidth" which does have an "off" position...although the "side chain mod" does use a switching jack to disconnect the signal from the trigger chip. So two ways to turn the trigger off. Maybe we can get the Aion guy to pipe up about that...

Makes sense. I checked the link to the meatball page you provided and it says:
"Trigger (Off / Full / 1/2)
selects triggering with hull or half bandwidth. In off mode, the effect can be used as a static tone control."
So Bandwidth in Spectron ought to be what was meant in the doc. (imho)

[matopotato]

Okey... That was "innaresting".
Built an audioprobe. Running my Trio+ (highly recommendable) with drums bass and guitar lines that I can mix as needed.
And the audio probe on the out.
I did not trace anything, but it was very cool to hear the sound on various points.
I will trace through the schematics, although not sure what to expect.
So first observations:
I tested pin 2 on the LM358P and no signal there. No signal on any of the LM358P pins as far as I could tell.
The TL072CP were playing on some of the pins, so they seem to be in the came to some extent.
Similar for the pots, some play, some are silent.
Then I did some random probing on some of the resistors. Is it safe to say that a resistor should have audio on both sides of it, or no audio on either side?
Some of them have audio on only one side (R2, but that might make sense if it is not really part of the signal path).
Capacitors, similar thing?
Diodes seemed to be one sided or silent, but I need some more "scientific" approach to all this.
(Hate to admit it, but there is an element of "fun" in this despite my disappointment in non-functioning pedal. I guess this is part of the evolution you need to go through to eventually be the winner of "Boutique Pedal Builder of the Year 2032")
The audio varied a lot from bassy muffled to very bright and clear, but I interpret "any audio is good audio" at this point.

The rotaries are not easy for me to understand. I soldered all pins on there, although I suspect you are only using A + 1,2,3,4 and A+ 1,2 respectively. Suppose the 10 an 5 pins that keep them connected are like "in and out". Or perhaps this part is functioning since they affect the "right" stuff. Sweep turns green LEDs on and off as expected, and Range clearly changes the tone at all 4 settings, probably ocatave-ish.

I also tested setting an EQ with two output first. Guitar in and Spectron on one out to the external trigger, other out to the board.
Then the Spectron in and out at the end of the chain.
And there is sound coming out, so I thin kthe ext trigger is working.
Also when the EQ is off, and I assume no splitting is done, it is kind of back to the "very few pots and switches have any effect" mode, but with the EQ on, I sense that more "knobs come into play". But as pointed out, it is a complex pedal that you need to understand how the controls interact and not.
But ext trigger working and if there is any clue in that ext trigger makes stuff better, then I am eager to learn.
But all in all, it sounds at its best quite subdued and several controls don't contribute anything much.
So plan is to read schematics and probe through the signal path. Although I am not sure if there should be audio everywhere.
If I encounter any paths without audio, then recheck soldering.
I suspect not having gotten enough solder to flow in on all places, or perhaps faulty component, but that is probably less likely (in my humble experience)

[idy]

Stop and simplify.
Almost certainly the one question you need to answer is:
Why is no signal reaching pin 2 of the 358?

We know everything else is working because sound gets through and when you adjust the brightness of the LED the filter...filters. Stop all further speculation, or shelve all further digressions until you  answer that question. Did you cut that bridge that bypasses the expression jack? Is that jack wired correctly? ("NC" switching jack?) Where does the sound die?

The only important path now is:
C4 (we know that's good, because that sends sound to both the filter and the trigger.)
"Side chain mod" pads and the jack that it allows
sensitivity pot
R5
bandwidth switch, leading to either C5 or C6.

[matopotato]

Stop and simplify.
Almost certainly the one question you need to answer is:
Why is no signal reaching pin 2 of the 358?

We know everything else is working because sound gets through and when you adjust the brightness of the LED the filter...filters. Stop all further speculation, or shelve all further digressions until you  answer that question. Did you cut that bridge that bypasses the expression jack? Is that jack wired correctly? ("NC" switching jack?) Where does the sound die?

The only important path now is:
C4 (we know that's good, because that sends sound to both the filter and the trigger.)
"Side chain mod" pads and the jack that it allows
sensitivity pot
R5
bandwidth switch, leading to either C5 or C6.

Will do, wasn't aware of the central role of pin 2 on 358.
When cutting the exp bridge I held DMM on pads until it went silent. Then I cut a touch more. Tried after wiring ad well. But no problem going back and check again.
Thanks for guiding me.

[idy]

The point about cutting that trace: if you had not cut it, you probably would not have the problem you are having.
If you have cut it that external control jack needs to connect those two pads, i.e. if it is wired correctly and it is the right kind of jack, you will still have continuity between those two points! If you don't, that jack is not right.

[matopotato]

The point about cutting that trace: if you had not cut it, you probably would not have the problem you are having.
If you have cut it that external control jack needs to connect those two pads, i.e. if it is wired correctly and it is the right kind of jack, you will still have continuity between those two points! If you don't, that jack is not right.

Thanks, yes I was beginning to think along those lines. It is an Amphenol, stereo. Same as loop and external ones. Will check it later this week. Again appreciate you steering me in the right direction.

[matopotato]

I think I might have found something. There is connectivity from C4 across the sidechain and Sensitivity pot until "start" of R5, but not the other side of R5
From R5 "other side" it connects to the C5 and C6 depending on BW setting to Pin 2 of 358.

I measured R5 and it comes back as 4k7 so R5 in itself seems be good.
So I resolder the joint towards the BW switch, fresh solder. No change.
Then I resolder both R5 pins. No change.
So I have connectivity from C4 to R5 on its closer side (to C4)
Then from the other side or R5 I have connectivity to the Caps depending on BW. And from them to Pin 2 is ok.

Maybe I should remove R5 all together and check the pads or something?
Or bypass them with wire?

Update: I guess the DMM connectivity test does not pass through Resistors. So I will check with the audio probe instead.