Internal Crossover Failure

[sameness]

The venue I am currently working in uses 9 Renkus-Heinz SR62H speakers as delay fills. Currently 5 of these speakers are only producing HF. The LF drivers themselves appear to be in good working order. Having tried by-passing each stage of the sound system up to and including going directly into the amp I am still only getting HF. Even after swapping out the LF drivers this makes no difference.

 

Is it common for an internal crossover to fail in such a way that only HF is produced?

[meyerm3d]

Its quite common for Them to fail. I've seen a lot of professional cabinets fail in this way. I once went to a venue full of Meyer UPA's and 4 of them had dead cross overs. Although I will say that it only tends to happen in really old equipment or equipment that has been misused ie dropped, overloaded e.tc what condition are the Renkus Heinz in ? They are pretty easy to fix, you just need a new cross over part from the company.

[tolley1466]

Surely if the crossover had failed it would have cut the signal completely?

 

Are all the contacts where they should be? Could they have a bulb/fuse in them that has blown?

[themadhippy]

Surely if the crossover had failed it would have cut the signal completel

All depends on crossover circuit,most are a parralel split.

[Stan Hope-Streeter]

...I've seen a lot of professional cabinets fail in this way. I once went to a venue full of Meyer UPA's and 4 of them had dead cross overs...

 

Oh? Are you quite sure of this?

[TallMike]

I always thought the Meyer UPA was a biamp box, or the +p version which has an amp module hence no passive crossover.

 

Bulbs are generally only used to protect HF - but maybe they have one - I've also known cabinets to have fuses in them. Your best bet is to take a good look at the crossover board, generally chokes, inductors etc on the LF side look pretty nasty when they've been overdriven enough to kill them. You should see a fair amount of melted plastic!

 

Take a picture!

 

Mike

[sameness]

The cabinets are in fairly reasonable condition, albeit they are 12 years old but the only real disturbance they get are vibrations from the ship.

 

Will drop a picture on later

[Simon Lewis]

.... but the only real disturbance they get are vibrations from the ship.

 

In that case, check that any heavy components or connections in the passive crossovers have not either snapped their leads off, or had the joint on the pcb go open circuit through vibration.

The components for the LF side will be heavier (hence the increased risk of problems from vibration), so if either scenario has taken place it's not hard to resolder and refix components with a generous dob of Araldite.

 

Simon

[Chappie]

I always thought the Meyer UPA was a biamp box, or the +p version which has an amp module hence no passive crossover.

The UPAs were biamped, but they still had a passive network inside them. I have a box of UPA-B networks that were replaced when we upgraded them to UPA-C.

 

Surely if the crossover had failed it would have cut the signal completely? Could they have a bulb/fuse in them that has blown?

Not necessarily. I have had a couple of pro boxes fail recently, with a loss of HF. On inspection, half the crossover components had melted, but the LF was still functional.

 

Being a bit pedantic, the bulb is part of the crossover, so if it was blown wouldn't that constitute a crossover failure?

 

Edit: sorted out my quotes a bit