KRK Rokit8 Powered Studio Monitor Repair

Steve used these monitors in his studio constantly. Unexpectedly, they broke. Can the Unbrokenstring Crew bring them back to life?

These monitors have no grille so the raw loudspeakers were given a little protection for the trip to the shop.

 

These are entirely self-contained, with power supply, amplifier, input attenuation, and high frequency controls built in.

 

Name, rank, and serial number, please.

 

The high frequency control rolls off audio energy going to the tweeter, thus acting as a simple tone control.

 

The balanced input line is a nice touch!

 

The fuse is located in a drawer built into the IEC power jack.  This fuse is open.  What caused this?

 

Let’s take a look inside.  I like all the acoustic attenuation batting inside this unit.

 

The swollen electrolytic capacitor is highly suspect.  Let’s test it.

 

This Chinese capacitor meter shows that all is well.

 

This kit ESR meter shows a very reasonable number for internal losses for a capacitor this size.  What gives?

 

The old 1950s technology Heathkit capacitor checker tests this unit at its working voltage.  Only at the full working circuit voltage does this capacitor fail.  Old Stuff Rules!

 

A couple of matched electrolytics are installed.

 

These monitors live to rock it another day!

Thanks for reading all the way to the end!

CONTACT – David Latchaw EE
281-636-8626

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