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General Discussions => The Lab => Topic started by: Skiroy on May 14, 2011, 04:02:26 PM

Title: Troubleshootin Big Knob Output
Post by: Skiroy on May 14, 2011, 04:02:26 PM
Hey guys I have a Mackie big knob I run my monitors through. I have had issues with my ASP 8 monitor going bad on one side. It sounded like my woofer would fart or pulsate when it was hit with hard low end. Then it developed a constant static. I was told this is a common issue with the ASP 8 so I changedc the pots and it seemed okay for awhile but then developed the farting again. I then bought 20/20 monitors and they seemed fine until one day I played some strings a little loud and then I heard a slight static develop. Its always the left side.

I thought it was my monitors but now Im suspecting either my Big knob or my Profire 2626 line out into the Big KNob. So the question is how can I test this? Would it be a voltage test with a sign wave and a multimeter?

I dont have an oscillascope, do I really need one?

Can someone spell this out for me because Im a noobie.



Title: Re: Troubleshootin Big Knob Output
Post by: tmuikku on May 14, 2011, 04:31:03 PM
Hey! Swap L and R cables before and after the big knob. Now your 2626s L output still goes to L speaker but through R "channel" of your big knob so you can continue working/listening normally and wait for the distortion to appear. Now if the fault appears in the R speaker, your big knob is busted ;) otherwise it is the 2626 or the speaker. This you can test by swapping speakers - still L distorting, 2626 is the culprit. No need for oscilloscope :)
Title: Re: Troubleshootin Big Knob Output
Post by: pucho812 on May 14, 2011, 10:46:00 PM
bypass the big knob and see if it's there, if it is then it's not the bigknob. if it is not there then it's the bigknob.
Title: Re: Troubleshootin Big Knob Output
Post by: Skiroy on May 15, 2011, 02:53:58 AM
Yes guys I have done this in the past. Unfortunately the problem had already ruined the amps in the monitors. Im concerned that the amps are getting overloaded on the inputs from the Big knobs or my 2626 >Big Knob's outputs and blowing the amps.