Voyager waveform pot/range calibration

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IgorCristo
Posts: 235
Joined: Thu Mar 29, 2012 3:03 pm

Voyager waveform pot/range calibration

Post by IgorCristo » Sun Oct 27, 2019 10:02 am

Hey guys,

I’m having some trouble with the osc1 waveform pot range. While the other two oscillators gives me a thin pulse wave, the osc1 wave pot have a full range, getting a 100% pulse width square (which is silent) around 90% travel.

Is there a procedure to calibrate this or is it a problem/faulty board thing?

I wonder this because if it’s something I can’t fix I’m probably gonna sell it. Can’t deal with gear giving me problems... don’t have the time in my life to fix anything, and the Voyager seems prone to problems.

Cheers
Moog Minimoog Voyager Performer Edition and Little Phatty Stage II | Elektron Analog Four and Analog Rytm | Mutable Instruments Ambika | Korg Minilogue

Markyboard
Posts: 314
Joined: Wed Jul 30, 2003 6:46 pm
Location: Springfield, VA

Re: Voyager waveform pot/range calibration

Post by Markyboard » Sun Oct 27, 2019 10:55 am

Hi Igor-

I don't believe there is anything "broken" with your Voyager. The pulse width/waveform is affected by several things and you should make sure that you do not have an unexpected modulation affecting Osc 1. This would include the Pedal and Mod Wheel buses. I assume you have nothing connected to the rear panel waveform CV jack as this would affect all 3 oscillators. But also check your Pot Mappings to ensure these are not affecting any waveforms.

Assuming none of these are set to affect the waveform there is a trimmer pot that can be adjusted for each oscillators waveform. But if I understand your post you seem to feel that at 100% the waveform should be a thin pulse? All 3 of of my oscillators go silent when the waveform knob is set to 100% which I think is desirable. So I believe it’s Osc 2 and Osc 3 that you would want to calibrate to match up with Osc 1.

IgorCristo
Posts: 235
Joined: Thu Mar 29, 2012 3:03 pm

Re: Voyager waveform pot/range calibration

Post by IgorCristo » Sun Oct 27, 2019 8:11 pm

Markyboard wrote: Sun Oct 27, 2019 10:55 am Hi Igor-

I don't believe there is anything "broken" with your Voyager. The pulse width/waveform is affected by several things and you should make sure that you do not have an unexpected modulation affecting Osc 1. This would include the Pedal and Mod Wheel buses. I assume you have nothing connected to the rear panel waveform CV jack as this would affect all 3 oscillators. But also check your Pot Mappings to ensure these are not affecting any waveforms.

Assuming none of these are set to affect the waveform there is a trimmer pot that can be adjusted for each oscillators waveform. But if I understand your post you seem to feel that at 100% the waveform should be a thin pulse? All 3 of of my oscillators go silent when the waveform knob is set to 100% which I think is desirable. So I believe it’s Osc 2 and Osc 3 that you would want to calibrate to match up with Osc 1.
Thank you very much for your reply.

As you thought, there’s no unexpected modulation on the waveform, and the range is different for osc1 when compared to the others (they sound exactly the same, a thin pulse wave when maxed, not silent 100% pulse).

I also think that is something related to an internal trimpot adjustment, limiting the range for osc1 waveshaping. The problem here is to find the exact one I should adjust.

I must state that my problem with this is that it changed the sound of all my sounds. The current point for the sawtooth wave is around the “number 2” while before it was around “number 3”. It made my editing much easier, and all oscillators were set to the same point to achieve the same waveform.

I’ll wait for Moog’s support to contact me. Sent a message today.

If anyone can also enlighten me with this, I’ll be very grateful.

Cheers!
Moog Minimoog Voyager Performer Edition and Little Phatty Stage II | Elektron Analog Four and Analog Rytm | Mutable Instruments Ambika | Korg Minilogue

Markyboard
Posts: 314
Joined: Wed Jul 30, 2003 6:46 pm
Location: Springfield, VA

Re: Voyager waveform pot/range calibration

Post by Markyboard » Mon Oct 28, 2019 10:40 am

IgorCristo wrote: Sun Oct 27, 2019 8:11 pm

I also think that is something related to an internal trimpot adjustment, limiting the range for osc1 waveshaping. The problem here is to find the exact one I should adjust.


Cheers!
RP13 for Osc 1 (it should be labeled on the board). I don't claim to fully understand how the waveform circuit works but it appears to be the only trimmer. Remember this will affect all of the waveforms, not just the square/pulse wave . Maybe best to confirm with Moog when they contact you.

Markyboard
Posts: 314
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Location: Springfield, VA

Re: Voyager waveform pot/range calibration

Post by Markyboard » Mon Oct 28, 2019 10:43 am

IgorCristo wrote: Sun Oct 27, 2019 8:11 pm

I also think that is something related to an internal trimpot adjustment, limiting the range for osc1 waveshaping. The problem here is to find the exact one I should adjust.


Cheers!
RP13 for Osc 1 (it should be labeled on the analog board). I don't claim to fully understand how the waveform circuit works but it appears to be the only trimmer in the waveform circuit area. Remember this will affect all of the waveforms, not just the square/pulse wave . Maybe best to confirm with Moog when they contact you.

IgorCristo
Posts: 235
Joined: Thu Mar 29, 2012 3:03 pm

Re: Voyager waveform pot/range calibration

Post by IgorCristo » Sat Nov 02, 2019 7:47 am

Markyboard wrote: Mon Oct 28, 2019 10:43 am RP13 for Osc 1 (it should be labeled on the analog board). I don't claim to fully understand how the waveform circuit works but it appears to be the only trimmer in the waveform circuit area. Remember this will affect all of the waveforms, not just the square/pulse wave . Maybe best to confirm with Moog when they contact you.
I got a response from Moog. It seems that the RP13 is indeed where I should try something, but he told me that it is meant to adjust the character of the triangle wave. I’m going to buy a marker to mark exactly the original position of the trimmer before doing anything. Maybe there’s some adjustment to be made on the 400 board trimmer.

I’m hoping this isn’t a major problem with my Voyager. If it is, I’m probably selling it for a Model D and finally end my constant fear of problems...
Moog Minimoog Voyager Performer Edition and Little Phatty Stage II | Elektron Analog Four and Analog Rytm | Mutable Instruments Ambika | Korg Minilogue

Markyboard
Posts: 314
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Re: Voyager waveform pot/range calibration

Post by Markyboard » Sat Nov 02, 2019 11:47 am

In addition to marking the pot measure it's resistance with a multi meter if you have one (power off). This way you can return to the exact same value if need be. Like I said this will affect all waveforms. With a scope you can compare the 3 oscillators but if you don't have one just try very minimal changes until you get the minimum pulse wave where you want it. Then check the triangle waveform at the opposite extreme.

By 400 board do you mean the Digital Board? No pots to adjust there for this issue.

This is far from a major problem. If you want a mini instead go for it. I have both and they are completely different animals in my view. One does not substitute for the other. And btw these calibration pots/ issues are in the mini as well, just not as many modulation inputs nor under software control.

IgorCristo
Posts: 235
Joined: Thu Mar 29, 2012 3:03 pm

Re: Voyager waveform pot/range calibration

Post by IgorCristo » Sun Nov 03, 2019 2:04 pm

Markyboard wrote: Sat Nov 02, 2019 11:47 am In addition to marking the pot measure it's resistance with a multi meter if you have one (power off). This way you can return to the exact same value if need be. Like I said this will affect all waveforms. With a scope you can compare the 3 oscillators but if you don't have one just try very minimal changes until you get the minimum pulse wave where you want it. Then check the triangle waveform at the opposite extreme.

By 400 board do you mean the Digital Board? No pots to adjust there for this issue.

This is far from a major problem. If you want a mini instead go for it. I have both and they are completely different animals in my view. One does not substitute for the other. And btw these calibration pots/ issues are in the mini as well, just not as many modulation inputs nor under software control.
I’m in no way an expert in electronics, actually a doctor... currently looking for a way to fix this minor “problem” with my oscillator. What brings me to worry is that in the future it might prove itself far more unpredictable than a D in terms of assistance here in Brazil.

I just did what the support told me to, to no success, but I’m confident I’m going to find a way of doing it. I do in fact love the Voyager sound, and exchanging it for a D might make me lose a lot of things I like on the Voyager, although some of the D’s strengths can’t be touched by the modern iteration.

I’ll keep searching for what to do next. Already sent another email hoping that I could somehow make it work correctly on the future.

Had a nice time opening it, took several phone pictures that I could actually share somewhere. Might put something here too.

Thanks once again!
Moog Minimoog Voyager Performer Edition and Little Phatty Stage II | Elektron Analog Four and Analog Rytm | Mutable Instruments Ambika | Korg Minilogue

Markyboard
Posts: 314
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Location: Springfield, VA

Re: Voyager waveform pot/range calibration

Post by Markyboard » Sun Nov 03, 2019 2:27 pm

Hmmm...OK interesting. I'm sure you can understand the sentiment "if only I had that patient on a table in front of me" :wink: . It's really difficult to troubleshoot remotely and so I or anyone else for that matter can only give you our best advice based on the results of the last attempt.

Here's my next line of thinking. As I said in a previous reply the waveform/pulse width is affected by a number of inputs; the front panel knob (obviously), the CV jack on the rear panel, the Mod wheel bus and the Pedal bus. Now if I did have that "patient" in front of me I would confirm that the other inputs are not providing any unexpected voltage offsets to the device that is summing them together prior to the waveform circuitry. I'm not advising that you try to look at this yourself but it may help with understanding.

Also one thing to be aware of is there have been some minor modifications to some of those inputs. If you have an older Voyager perhaps you have the original resistors in place? This is just a guess on my part but maybe something to bring up with Moog.

Hope that helps.

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MC
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Re: Voyager waveform pot/range calibration

Post by MC » Sun Nov 03, 2019 4:25 pm

Many reasons why I no longer fix things over the internet: http://www.analoguediehard.com/faq.html ... air-advice
Gear list: '04 Saturn Ion, John Deere X300 tractor, ganged set of seven reel mowers for 3 acres of lawn, herd of sheep for backup lawn mowers, two tiger cats for mouse population control Oh you meant MUSIC gear Oops I hit the 255 character limi

IgorCristo
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Re: Voyager waveform pot/range calibration

Post by IgorCristo » Tue Nov 05, 2019 5:27 pm

MC wrote: Sun Nov 03, 2019 4:25 pm Many reasons why I no longer fix things over the internet: http://www.analoguediehard.com/faq.html ... air-advice
I wouldn’t even try to mess with anything inside it if I lived in a country where I could take it to an authorized service center. Unfortunately there’s none in Brazil. Electronics isn’t something hard to learn, but I don’t have the time or need for it.

In the end, the problem is actually quite small, and ill try to live with it. The only thing is that osc 1 differs waveforms compared to 2 and 3.

The only thing I can’t understand is why it would happen without any real cause/hardware thing. I believe something went wrong, either with the pot itself or the analog board.

It still sound amazing.
Moog Minimoog Voyager Performer Edition and Little Phatty Stage II | Elektron Analog Four and Analog Rytm | Mutable Instruments Ambika | Korg Minilogue

Markyboard
Posts: 314
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Location: Springfield, VA

Re: Voyager waveform pot/range calibration

Post by Markyboard » Tue Nov 05, 2019 7:20 pm

Hi Igor-

It could be that the potentiometer is degraded. In case you’re unfamiliar it’s the mechanism that the front panel knob turns providing a variable resistance based on its position. Being a mechanical device they are prone to wearing out over time.

Is it possible for you to get hold of a multimeter and measure the resistance at the extreme positions of the potentiometer and compare it to oscillator 2 and 3?

Again maybe something to discuss with Moog.

IgorCristo
Posts: 235
Joined: Thu Mar 29, 2012 3:03 pm

Re: Voyager waveform pot/range calibration

Post by IgorCristo » Wed Nov 06, 2019 7:16 am

Markyboard wrote: Tue Nov 05, 2019 7:20 pm Hi Igor-

It could be that the potentiometer is degraded. In case you’re unfamiliar it’s the mechanism that the front panel knob turns providing a variable resistance based on its position. Being a mechanical device they are prone to wearing out over time.

Is it possible for you to get hold of a multimeter and measure the resistance at the extreme positions of the potentiometer and compare it to oscillator 2 and 3?

Again maybe something to discuss with Moog.
Thank you once again. Yes, this is doable. I’ll try this as soon as I have the time for it. If it’s just a bad potentiometer I can understand and accept it - my fear is if something is wrong with the analog board or not.

Someone gave me advice for a guy here in Brazil that can fix this kind of stuff, but I surely would like to know what the problem actually is before sending it to him.

Cheers!
Moog Minimoog Voyager Performer Edition and Little Phatty Stage II | Elektron Analog Four and Analog Rytm | Mutable Instruments Ambika | Korg Minilogue

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