PA Speaker Parts

paulphoenix

@ICBM photo as requested.

Wires on the pcb were labelled/connected:
Yellow HF -
Blue HF +

Black LF -
Red LF +

Will I have to replace this crossover to run a compression driver? 

Thanks (to everyone) for your help and input. 

paulphoenix

http://cpc.farnell.com/eminence/eapt150v2/eminence-pro-tweeter-45w/dp/LS00196

Based on what @ESBlonde ;; recommended would these be ok to use? 

They will fit the existing cut out.Confusingly quoted as 45W on Thomann. 

ICBM

paulphoenix said:

Will I have to replace this crossover to run a compression driver? 

OK, there's a problem. The 16-ohm resistor is purely in series with the tweeter, not bypassed by a cap. That means it will take twice the power that goes to an 8-ohm tweeter, and since it's only rated for 20W that means the tweeter can't take more than 10W before the resistor burns out. That means the whole system would be limited to about 100W before the crossover fails.

There's also no inductor bypassing the tweeter - it's in series with the bass driver, which I wan't expecting. Normally cheap cabs have all the crossover on the tweeter and allow the bass driver to just do its own thing, since it doesn't respond to, and won't be damaged by, high frequencies.

Bottom line - this crossover is not suitable for a compression driver after all.

paulphoenix said:

http://cpc.farnell.com/eminence/eapt150v2/eminence-pro-tweeter-45w/dp/LS00196

Based on what @ESBlonde ;; recommended would these be ok to use? 

They will fit the existing cut out.Confusingly quoted as 45W on Thomann. 

Very low on power rating for this application, but you *might* get away with it with the right crossover.

paulphoenix

Thanks for checking into this so thoroughly ICBM it is appreciated. I’d kind of resigned myself to the fact I’d need new crossovers so I’ll likely go for the ones you linked previously (as they are a good price) and then look for some 50-70w drivers. Are there any particular makes to avoid especially at the lower end of the market where I’ll be shopping ? How are soundlab and MCM audio? I’d be willing to stretch the budget for better drivers.

paulphoenix

Update: new crossovers have been ordered as per ICBM's suggestion above, and some cheapo (probably chinese) 70w Soundlab drivers have been order for shoehorning into my existing flares. 

This will not only fix my original problem (broken piezo) but also upgrade my speaker as a whole and should return an improved sound quality overall (YMMV). 

No further questions M'Lord ! 

paulphoenix

For those (like me) who enjoy getting closure on Fretboard threads and, before this one drops into the depths of obscurity - here's how this all turned out for me:

The new Soundlab  drivers and QTX crossovers arrived (grand total £53.47).
  
The speakers were dismantled, I installed the new crossovers (part solder/part spade connectors) and binned the old piezo units that were taken off the horns/flares.

This left me with the original horns/flares which I wanted to retain and reuse for reasons of both cost and convenience. So I removed and stowed the new driver's screw adaptors (just in case they're needed for any future projects) and made a  flange that would screw to my flare and then bolt on to the driver like so: 



The blue stuff is an old microphone pop shield that I cut and used as a seal between my flange and flare, and the driver came with a foam gasket (not pictured) to seal the other face. 

I am really happy with how this all went, and once put back together later today I'm hopeful that it makes a marked improvement in the overall sound quality of my speakers. 

Thanks to all that contributed.  

/thread.