KRK Rokit 5's malfuntioning

[G0G0MRM0J0]

I don't know why this is happening, but I own a pair of Rokit 5's... and one of them seems to be emitting something similar to a 60 hz hum and the woofer is being retracted into the cabinet... This is regardless of input. As far as I can tell, it is not capable of recieving input, and this happens immediately when the monitor is turned on.

Please help... I am at a loss with what to do here.

Thanks,

Jules Taylor

[Geoff_T]

Originally Posted by G0G0MRM0J0

I don't know why this is happening, but I own a pair of Rokit 5's... and one of them seems to be emitting something similar to a 60 hz hum and the woofer is being retracted into the cabinet... This is regardless of input. As far as I can tell, it is not capable of recieving input, and this happens immediately when the monitor is turned on.

Please help... I am at a loss with what to do here.

Thanks,

Jules Taylor

Hi

You'd be better off posting this in the Geekslutz forum!

If the cone is sucked backwards it means that you have a dc offset in the output of the driver amp that's negative going. It could be a lot of things... duffo power supply rail feeding the speaker amp, duffo transistor, duffo electrolytic capacitor leaking volts on the feedback path, etc.

The thing obviously needs fixing by someone with the skills, parts, and diagram to fix it. I wouldn't recommend switching it on again until then or you might harm the speaker.

[RusRant]

I've actually heard of this happening from the guy that sold me my new monitors to the Krk rokits. I don't know if that makes it common or not, but I have heard of it. If it's still under warranty, get in contact with them ASAP.

[Dave Peck]

.... and when they repair the amp circuit make sure they replace the drivers, especially the tweeter. Subjecting the drivers to DC has likely taken a toll on them.

DP

[PhilRanger]

DC on the tweeter??? Aren't all tweeters always high pass filtered by a capacitor that would totally eliminate DC anyway (except a short burst on start)?

[Geoff_T]

Originally Posted by PhilRanger

DC on the tweeter??? Aren't all tweeters always high pass filtered by a capacitor that would totally eliminate DC anyway (except a short burst on start)?

Hi

I don't know anything about KRK's but they may be bi-amped with filters to the inputs of the amps and a separate amp feeding each speaker.

[Dave Peck]

If you can see that the driver is being sucked back into the cabinet, there's DC being passed to the driver. There may or may not be some DC protection on the tweeter, but it's pretty clear that there isn't any for the other driver.

[G0G0MRM0J0]

Unfortunately, my warranty ran out on 5-05 of this year... I've been advised by the folks at KRK that the speaker is defective and needs repair by a company called High Tech Electronics out of Boston...

There's a $40 bench charge + any labor and repair costs... which sucks because I don't know what repercussions this may cause as far as how the speaker performs.... and granted these speakers retail at $150 each (I know... they're at the lower end of the spectrum) but I think a new set of monitors, taking into account the money I would have to spend to fix this speaker, is in line.

I've really grown to trust these speakers over the time I've had them and having to switch monitors wasn't something I was planning on.

I won't say that my next set of monitors will not be KRK's... even though this obviously damages the trust I had with the company after investing in their gear. It just means that my studio is down until I can get a new set of monitors.

You buy the best once, and you have it for the rest of your life. You skimp, you buy twice. It's a lesson I knew, but when you're a small scale project studio owner, you do the best within your budget (as long as you stay away from Behringer). The Rokit 5's are awesome little speakers for the usage I got out of them.... but it's situations like these, where you're really not left with any alternative but to scrap gear and re-invest, that really drain the creativity and inspiration out of you.

I'm still a fan of KRK.... but something about this whole situation reminds me of the way american cars seem to last for 10 years before things start falling apart.

Jules Taylor

[Goliath|Audio]

Originally Posted by G0G0MRM0J0

You buy the best once, and you have it for the rest of your life. You skimp, you buy twice.

I would say that this is the truth... the Behringer Truth.

But in all reality, I have never liked the sound of the KRK monitors. I would look at this as your chance to graduate to something that will give you the "new glasses" effect. Recco on ADAM or Genelec, they both are well built and ear-opening.

[G0G0MRM0J0]

Yep... I'm looking foward to graduating into a pair of HD824's. Genie's and Adams are a bit out of my price range (I know there are a couple low end Adams)... but from what I've seen the 824's are somewhat of a standard... and they're not too flattering either. The Genies seem to embellesh a bit too much IMHO. It's all subjective though.

No better, No worse... just different.

Looking foward to graduation,

Jules Taylor

[Goliath|Audio]

Actually the 8030s are a little less. I don't like the outta control low end, or the weird high end for that matter on the Mackies.

[PhilRanger]

Originally Posted by Geoff_T

Hi

I don't know anything about KRK's but they may be bi-amped with filters to the inputs of the amps and a separate amp feeding each speaker.

Thanks for correcting me. Seems I forget even the basics some days