Help with L/mono and R outputs

Kaedyn · Post by **Kaedyn** » Sun Aug 09, 2009 4:38 pm

The other day, I decided to create a panning effect for a sound I was working on. After several minutes of fighting what appeared to be a real simple operation, I realized that no matter how drastically I panned left or right, all I got was stereo (or so I thought). So I decided to try through a pair of headphones. Much to my delight, it was doing exactly what I wanted, panning left and right.

So, I tried again through my monitors and nothing, it wasn't panning at all. As a matter of fact, when I compared it to the phones, I realized all I was getting from my monitors was two channels of the same mono sound. So, I moved the instrument cables from the L/mono and R outputs to outputs 1 and 2, then in the global menu I diverted the left and right channels to them. What do you know, I had a perfect stereo effect, panning and all.

Of course this leaves me wondering what I'm doing wrong with the L/mono and R output? Is there some setting that I've missed or accidentally messed up? I know that the manual claims that if there is no cable in the right output, it will mix the left and right signals to mono. Could it be that it's not detecting a cable in the right output so both channels are receiving the mono mix? Is anyone else seeing the same thing? If you pan fully left or right in the AMP section of a program, do your L/mono and R outputs actually pan? I could definitely use a sanity check here!

ktippets · Post by **ktippets** » Sun Aug 09, 2009 8:59 pm

My advice is to check your physical L/R output jacks - they should match the mix that you hear in the headphone jack.

I have a relatively new (6 months old) M3M and recenty experienced the same issues that you described coming from the main L/R output. It turns out to be a faulty R output jack: if I turn the instrument cable inside the jack 180 degrees it will eventrually engage and the true stereo mix will return. When it isn't engaged I get a mono mix. I live 500 miles from the nearest authorized service center so for me this will be 2 to 3 weeks to send it in for warranty repair... In the meantime I have an adapter I use to go from the headphone jack to 2 1/4 inch outputs so I make sure to have a true stereo mix (expecially when playing live and sending feeds to a FOH engineer).

Kaedyn · Post by **Kaedyn** » Mon Aug 10, 2009 7:38 pm

Mine is also just a few months old. I was afraid that might be the case. It definitely does not match what I hear in the phones. I was hoping it was just some setting I had overlooked and not a physical issue with the jack. I'll play with the cable tonight and see if I can get it to behave.

a.schemkes · Post by **a.schemkes** » Tue Aug 11, 2009 1:16 am

Obviously there is something wrong with your mixer settings and not the M3. Did you pan on your mixer outputs L completely to the left en uotpu right completely to the right?

I asume you use a mixer, for controlling the monitors.

ktippets · Post by **ktippets** » Tue Aug 11, 2009 3:36 am

My issue is definately the M3 - it is intermittent and comes and goes if you wiggle or rotate the instrument cable in the R output. I initially thought it was the cable, but it does it with every cable... I discovered it with a radias patch that pans left and right and it suddenly stopped panning and everything was panned in the middle.

Kaedyn · Post by **Kaedyn** » Tue Aug 11, 2009 2:24 pm

I ran a test last night and I have to agree with ktippets. If I rotate the cable 180 degrees it switches to stereo and I hear audio only in the speaker that I've panned to. When the cable isn't rotated in the jack, I hear mono from both speakers regardless of panning.

I read in the manual that the M3 will mix the stereo signal to mono when it doesn't have a cable in the audio jack for channel R. It appears that whatever mechanism is used to detect an inserted cable is damaged.

I'm so torn. I REALLY don't want to have to send my M3 away. I can get stereo audio from jacks 1,2,3, & 4 for now.

Kaedyn · Post by **Kaedyn** » Wed Aug 12, 2009 1:13 pm

I performed another test. This time I swapped cables to see what the results would be. Using the same brand of cable the problem existed unless I twisted the cable in the jack 180 degrees. Using another brand of cable, I didn't have the problem. I compared the plug at the end of the working and non-working cable and found them to be identical in every way, with the minor exception that the start of the tip, where it meets the ring is more rounded on one and slightly sharper on the other. I'm guessing that the mechanism in the M3's jack is just not able to handle this slight difference.

The question now is, are the jacks in my M3 any different than any other M3? Are mine less tolerant of some cable designs or are they all the same and I just need to be careful which instrument cables I use?

Matthiola · Post by **Matthiola** » Wed Aug 12, 2009 2:17 pm

I've had an 88 key version and now a 73, which both have this problem. The R output has a switching mechanism that feeds the L/MONO output when left unplugged. It appears that this mechanism doesn't work properly with some jack plugs, like Planet Waves molded plugs. I've found that these plugs have a slightly different shaped tip (smaller 'tip collar' for example), than say Neutrik. You can verify this by gently pushing the plug upward, you'll hear the mono/stereo switching. Seems these sockets aren't very tolerant indeed. As far as I'm concerned this is a design flaw, I've never had this kind of problem in 25 years playing keyboards...
By the way, I now use Neutrik NP-X jacks and these work perfect.

ktippets · Post by **ktippets** » Wed Aug 12, 2009 3:22 pm

Thanks Matthiola! Where can you find Neutrik NP-X jacks?

Matthiola · Post by **Matthiola** » Wed Aug 12, 2009 5:12 pm

It is standard stuff here in Europe, probably harder to find in the States. I order cables and plugs from www.thomann.de. They also have a lot of premade cables with Neutrik plugs (Cordial, Sommer Cable). Maybe Switchcraft plugs will also work fine, or any quality plug for that matter...

midime · Post by **midime** » Thu Aug 13, 2009 2:57 am

Ah, and I thought it was my bad luck. Will Korg service this if the unit is under warranty? I'm using the outputs 1-2 bus for now...

thanks for posting

mm

ktippets · Post by **ktippets** » Thu Aug 13, 2009 3:22 am

I had been considering sending my M3M in for warranty repair on this issue...but if the flaw is in the connectors themselves it will likely get sent back unfixed because they couldn't find anything wrong with the output jacks OR they will get replaced with the same (but new) jacks.

It seems that the solution is finding instrument cables that the M3 'likes'. When I send a mix to an engineer for a live performance I have to be confident that they are actually getting a stereo mix. So, for now, I tap into either the headphone jack or reroute everything through individual 1 and 2.

If anyone here in the States has found a brand of instrument cables that work I would appreciate that info...

I love my M3 - I think this is a just a quirky design flaw (and/or cheap hardware).

dswtan · Post by **dswtan** » Sun Dec 06, 2009 9:08 am

Just a quick +1 on this same fault/feature with my M3-M purchased October 2009. I'm using a cheap Hosa stereo snake cable. Mystified me at first too.

McHale · Post by **McHale** » Sun Dec 06, 2009 10:08 am

same issue with mine. If you don't push the R cable all the way in, you'll get stereo.

Oddly, my Triton and M50 do NOT have this problem with the exact same cables.

-Mc