HK Audio Emergency

[Vin Trouble]

Guys, I'm running a duo with an old HK 1000 Watt speaker system - like the LUCAS with the amps in the sub and two satellites. My question is this - I have recently replaced one of the 8" drivers in the satellites as it was starting to fart out on some bass notes. However, the new one is only 4 months old and now it's on the way out when my singer Gives it some. It's almost impossible to get a replacement in the UK, taking six weeks last time, so can I fit a generic 8" 16 Ohm 200watt replacement instead? Would a higher wattage be an issue? Also, we have an important gig this week, so if push came to shove, could I run one side of the desk into another active speaker, and the other side into the HK, which would mean (I think) that there would be no load on one of the internal amps, the one that drove the dodgy speaker, which would absent. I know a valve amp is a no go without a load, but what about the HK.Sorry for such a long winded post, but I would be great full for any help.

[sam.spoons]

Short answer, yes you can use a generic driver as long as it has the right impedance and at least as many watts. Longer answer, it may not sound the same, may be louder, or more probably not as loud as the cab with the original driver. No load on the internal amps should be fine, trannies are more forgiving than valves but without knowing which specific system you have I can't be sure (tip, if it says "mosfet" in the power amp description you're probably ok here). But, I'd want to know why a 4 month old driver from a reputable company like HK is failing so soon. Ask yourself questions like "does the amp have a fault "(I assume you've tried swapping the tops to see if the fault is with the speaker or the amp?), "am I asking too much from the system and driving it into clipping"?

 

HTH

[Vin Trouble]

Hi, Thanks for your reply. I have changed tops round, and it's defo the new driver. When using the setup live, there are 3 LEDs on the sub, one for each channel, and nothing ever turns red, only stays at green. Probably not a definitive sign that everything is ok, but it's all my Luddite self has. Not having someone out front post- sound check doesn't help, but I don't hear anything to suggest I'm pushing too hard. Worth mentioning the sub has 3 pots- one for each channel- I turn each of these up full and control the sound from the sliders on the desk.

 

 

[StevieR]

Could also be a fault in the internal crossover in the satellite??

 

If the upcoming gig is important, perhaps consider renting a system to cover you for this while you get your box properly looked at?

 

Steve

[sam.spoons]

Sounds like you've got all the bases covered, those green LEDs are a good sign.

 

However, it's pretty unusual for a driver to fail so soon unless something is going wrong elsewhere in the rig (age gets us all unfortunately so the original driver may have just reached the end of it's useful...), I'd be trying to get an exchange on the new driver as faulty from new.

[csg]

the new driver " farting' on the satellite when things get loud is a sign of low frequencies, below the intended crossover point reaching the box.

 

Drivers, whilst getting softer with age wont generally fail unless there is a good reason. Mid range drivers, driven properly should have an almost indefinite lifespan with no suspension failure due to the very low excursion ( movement) produced by mid range frequencies when the speaker is in a properly tuned enclosure.

 

So, something is going on here to make the driver fail - and it is likely that the original driver was a victim of this, as well as the replacement.

 

I strongly suggest that you take the system to someone who can test the system properly, looking at the output from the amplifier modules ( either DSP failure or DC present) and also the condition of the cabinets ( cracks, or anything else that can leak air, but should not be there).

 

In response to the answer about dropping an alternative replacement driver - its not quite as simple as finding a driver with the same impedance and power handling - enclosures are tuned precisely to the characteristics of a driver, so you would have to also consider Sd, Fs, Qts, Qes, Qms, X-max and sensitivity - otherwise the system will sound quite different, and likely prove just as unreliable......

[Dave SA]

Please listen to CSG.

[DrV]

I'm very familiar with the LUCAS 1000 and can confirm that, like almost all transistor amps, it will be perfectly happy running into no load. If you are anywhere conveniently nearby (postcodes KT20 or KT13) then feel free to get in touch regarding repair.

 

Dave

[Vin Trouble]

Hi, Just a quick update - going down the QSC K8 plus sub route, so the HK will sit out of the loop until I get her sorted. Thanks for the offer, Dave- if I was handy I'd pop over - unfortunately I'm up in the frozen North -Glasgow. Thanks also to everyone else who posted, I really appreciate your learned responses.