do powered monitors need recap or other maintenance?

realized my HR824's are giving a bit of distortion lately and was wondering if the caps on the build in amp could have started to wear out?
Have replaced a woofer in 1 of both 3 years ago, and did not notice any difference between left/right after this. Other then that no real maintenance was performed.

They've been used almost daily since the year after they became available (forgot when , but estimate something like 10 years ago now)

What kind of distortion? Have you noted the frequency of the distortion when you sweep an oscillator? Is it a 'scraping' noise? If so, the surround could be going on your driver - this is common on quite a few older monitors, but it's unusual for a 3-yr old driver.

IMHO, any kind of modern cap, electrolytic or otherwise, should last longer than 10 years unless there's a fault in the design whereby it's run too near its limit or it gets too hot (in certain consoles...). Film caps last for decades.

My suggestion is to connect an oscillator and sweep a sine upwards from a low frequency, say 20 Hz-ish. Note that if the surround is going, it's likely to introduce distortion above a certain amplitude - you may not hear the drive coil hit the magnet assembly until a certain level.


Justin

Not so much the speaker surrounds as the passive radiator on the back... VERY common failure on those models, I recall.

Replacements are pretty cheap I think... -amorris just repaired a set for a friend of his: he should know the cost.

Keith

not distortion in a way like everyone would notice.
We noticed a difference in sound when listening to wellknown cd's in between the session. Have to sweep etc to find out more, it is not damage to speakers as far as we've verified. Both monitors seem to have more or less the same thing going on. I was just asking about caps and such, as this seems like a logic thing after +10 years?

Note to self, is your cd player still fine?

Keith,

If I use the low cut at max, the passive speaker will become more or less bypassed?

you replaced the woofers but what about the tweeter?

maybe they need to be replaced as well :?

I've always regarded passive radiators as pretty esoteric - it surprised me to see Mackie adopt them.

Along similar lines to Keef's point (probably quite a relevant point) about the PRs having issues, according to AE, my AE1 were only the second pair out of 10,000 sold to have a bass port tube come loose on... Have you ever seen the price of AE1 drivers? :shock: I heard a 'scraping' and decided it was the foam and ordered a pair of new drivers... You wouldn't have wanted to have seen my face when I powered them up after the rebuild and still heard the zzzpp noise...

I regret selling the AE1 - with new drivers the buyer got a bargain. I couldn't handle the alloy tweeter anymore, but then again, mixing monitors aren't meant to be 'fun', are they?

Justin

Pucho,

I replaced only 1 woofer after it got damaged from the outside. The second monitor was never touched. After this they both sounded pretty much the same.

The passive radiators still feel ok, you can touch the edges at the back of the monitor. We'll perform some listening test this evening.
My post yesterday triggered my mind in assumption it might be the cd-player, since the degradation is similar on both left and right channels.
Well rip a song from the reference cd and playback via our DAW outputs.