Moog Music Forum

I just realized that you actually can order the new digi board with instructions on how to install it. It's an upgrade from 128 patch slots to 896, so it's not just a possible fix for my issue, but a nice functional upgrade. Not too expensive either, $265. But I'd really like to get hold of an early...

If your Voyager under warranty? Not from Moog, it's an SE from 2002. It's under limited warranty from the shop that sold it to me. Problem is, their tech isn't a certified Moog tech... If I can verifiy that the issue is the combo of OS 3.5 and my early digital board, I guess I'm gonna have to have ...

Some more info. 1) I've discussed the TL074 with a group of extremely knowledgable audio engineers AND analogue synth buffs. They rejected the notion that it's unsuitable for audio. We're talking about people who are either analogue audio engineering professionals, or the kind of DIY synth builders ...

Hey jonas Damn annoying.. when a problem like this occour.. :( How does the "noice" behave?? does it get worse when you turn the knobs?? .. or?? Is it a loud noice ?? best regards Morten what have you tried and not tried? Factory resetting and updating the OS (it was 2.something when I bo...

Hey, I just went back and checked and actually, the crackling is present at the insert point too. So it seems, the fault must lie earlier in the signal chain than I thought. Also, I get the crackling even with no oscillators on, it's enough to turn up the external input level. No need to actually fe...

Only one Opamp was changed ( 074) I allso put in a new headphone jack socket.. but thats another story Is this "crackeling noise on both outputs.. Main and Headphone ??? best regards Morten Hi Morten, I realized that you only changed one opamp, but it's not unlikely that there's more than one ...

Just so to be clear, I have no idea if U49 is the IC that was replaced MotneN. The 837 is designed for audio and should be fine. I do not know if earlier voyagers used different IC's and were later changed to the 837, but if your's has the 837 in it already, I'd suggest leaving it, unless it is bad...

The replaced opamp is designated U49. Opened it up last night. Yep, U49 is where I was looking. OK, thanks a LOT for looking! Saved me a bit of head scratching there... :) Well, I read somewhere on this forum that three opamps could need replacing, to fix issues with the output section of early mod...

muksys wrote:I'm out of town ATM, but I'll check when I get home tomorrow night.

Thanks, great!

It seems this replacement may already be done by a tech, in an (unsuccessful) attempt to solve an issue I'm having with a "crackling" noise.
The replaced opamp is designated U49. Anybody happen to know if that's the opamp we're talking about here?

Thanks!
/Jonas

324, 837 & 074 are pin for pin the same. All are interchangeable. Shouldn't need any other changes. Be sure to drop in an IC socket for easy swappage in case it's not to your liking. Thanks! Yeah, I certainly will use a socket. If it's not socketed already, I guess I'm gonna have to to take the...

It should be an easy switch out. Just remove the LM324N and put the LM837N in its place. :) So no electrical differences that would require, say, a different resistor value here or another cap value there? That sounds great! Now I just need to find the time to dig in to my Voyager. Will report back...

There are several versions of the LM837 too, LM837, LM837M, LM837MX etc. What exactly is your 837 called? What brand? (Texas Instruments, National Semiconductor etc). LM837N National Semiconductor Great, thanks! Now I just gonna have to figure out if it can be used as a drop-in replacement for the ...

So, I just took a peak into my OS and found the headphone jack is driven by an LM837, which is designed for "professional audio applications". It's the same pinout as a TL074, so I wonder if this was something that was caught and corrected with new boards. Mine is from the second run of O...

Is there a way to just sum the filters to mono, put them in series (much more useful) or simply disable one of the filters? Judging from the manual, putting the spacing knob at the center position should do it, but even after putting it at an LCD-confirmed dead zero I can hear some panning. There a...