Rockman x100 headphone output problem

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Wolfman
Posts: 2
Joined: Tue Jul 20, 2021 9:06 pm

Rockman x100 headphone output problem

Post by Wolfman »

Hi everybody!
I have a rockman x100 and I have a problem so hopefully someone can give me a tip. When I use headphone output only one of the headphones has sound, the other is silent. What seems to be the problem? Both stereo outputs behave the same... When I wiggle the jack around I can hear guitar on both sides but it is just a mono signal no stereo. How do I fix the issue?
Thank you,
Regards
X100Ver10
Posts: 141
Joined: Mon Sep 18, 2017 2:49 pm

Re: Rockman x100 headphone output problem

Post by X100Ver10 »

2 common issues with these Rockman headphone amps:

1) The solder joints for the headphone jacks get broken from use. Re-solder all the joints. Try this first.
2) One or both of the LM386N-1 IC's is bad. If just 1 is bad, I recommend replacing them both.

I was a little confused about the way you described your issue. If both headphone jacks only have sound coming out of one side of your headphones, it is probably a bad IC. If you get sound out of both sides of your headphones while wiggling the jack, you might have broken solder joints. What is confusing to me is when you say you wiggle the jack and can hear the guitar on both sides but it is mono and not stereo. If you can hear the guitar on both sides, wouldn't that be stereo? :-)
Wolfman
Posts: 2
Joined: Tue Jul 20, 2021 9:06 pm

Re: Rockman x100 headphone output problem

Post by Wolfman »

Thanks man I really appreciate your response, as I havent found anything about it on the internet.
The thing is when I plug headphone jack till the end I hear the sound coming out only from right headphone. But when I push it about halfway(and wiggle it about), I can find a sweetspot and I can hear the sound coming from both headphones. On both headphone jacks the problem is identical. When I can get the sweetspot by wiggling around the signal I get is mono - the same signal on both headphones. By stereo I mean slight difference in sound giving the stereo effect. When I use AUX out and connect it to my pc I get stereo sound, which is awesome, but the signal is so low so I would prefer if I could use headphone out to connect to my PC.
X100Ver10
Posts: 141
Joined: Mon Sep 18, 2017 2:49 pm

Re: Rockman x100 headphone output problem

Post by X100Ver10 »

Wolfman wrote:
Thu Jul 22, 2021 6:41 pm
Thanks man I really appreciate your response, as I havent found anything about it on the internet.
The thing is when I plug headphone jack till the end I hear the sound coming out only from right headphone. But when I push it about halfway(and wiggle it about), I can find a sweetspot and I can hear the sound coming from both headphones. On both headphone jacks the problem is identical. When I can get the sweetspot by wiggling around the signal I get is mono - the same signal on both headphones. By stereo I mean slight difference in sound giving the stereo effect. When I use AUX out and connect it to my pc I get stereo sound, which is awesome, but the signal is so low so I would prefer if I could use headphone out to connect to my PC.
Sorry, just got back home from vacation and saw your response.

Probably what is happening is, when pulling out the plug halfway and wiggling it just right, contact is being made with one of the contacts inside the headphone jack with both sections of the headphones jack plug. You may be hearing sound out of both sides of your headphones but it isn't really stereo. Both sides of your headphones are getting sound from the right side of the amp, the side that is still working.

Are you handy with a multimeter? If so, I can probably tell you if one or both of the LM386N-1 IC's is/are bad, if you provide me with the voltages on each leg. More than likely, if you replace both of them, it will resolve your issue though (assuming you've already made sure the headphone jack solder joints are good first). The other component that I've seen cause this issue is the capacitor at location C209 but that is rare.