Sound Problem

[andyw 0]

ok i'll start at the begining we are using a pv1500 amp,pv pro12 tops and matching bins and a numark cm100 mixer and numark cdn88 cd decks and a laptop with sam on.went vout on thursday 2 school disco's 1 after the other. set and and sounded poor,all tops no bass increased the bass to get sounding reasonable half way through 1st gig amp starting clipping and cutting out.reduced volume got through 1st half.spoke to ads who suggested taking the bass off to stop the amp clipping.done that got through secound gig.set up at home on friday to find the problem,noticed a rattle inside bss bin,opened her up and found thecrossover had worked free.sorted problem went to gig on friday set up and sounded pants again,replaced the speakon cables for new ,sounded better but not good.tried a hz power speaker in 1 side again slightly better but not right.today replaced all cables in the sound from the mixer to the speakers and no real improvement.it sounds like all the sound is coming out of the horns and bass bins on both sides and no mid.could the mixer cause this or do you know any other reasons.

[superstardeejay 0]

Have you got the correct speaker leads? If you bought the bass & tops as a set, the link leads from bass to top are wired differently from off-the-shelf leads. Maybe you should try your old leads again? Dont forget you have to plug the correct ends into the correct cabs..they arent symmetrical.

 

 

 

 

[norty303 0]

From the info i can find online, your speakers are rated at 4ohms per cab, both subs and tops. However the owners manual says that even with tops connected the minimum impedance will be 4ohms at the amp so you're running them within limits, although underpowered for the whole setup (I'd say you'd want an amp that gives 750w - 1000w per side at 4ohms really) which is why you're experiencing the clip light.

 

If the amp is cutting out (thermalling) when driven into clip then I'd suggest its not a great amp or something else may be wrong. If one of the mid drivers has 'partly' blown it may be a part dead short, significantly reducing the impedance the amp sees and causing the cutting out and lack of midrange.

 

Make sure you have the speakons in the correct holes, you should be going into the subs first and one of the sockets should be marked as an output, which should go to the tops (this is only relevant on cabs with internal crossovers, as otherwise everything is just parallel with the driver so you can use either socket)

 

I'm not a fan of internal filters in subs, you'll get much better sound using another amp and an active crossover, however the points above may help to trace the issue. Also, check the x-over in the subs, as it may have become damaged when it fell off and by some chance caused the cab to simply pass thru, so the amp would be seeing a 2ohm load and hence the cutting out.

[andyw 0]

the amp was only cutting out and clipping on the 1 night.that seems to have stopped since.but the sound only seems tobe coming out of the horn and bins.

[rictic 0]

are these hz cabs and subs?

[andyw 0]

 

 

no the main speakers are pv,the hz's are back up powered speaker(pe 300),we use 1 of them a lot at a regular venue to get music to the bar area.

Edited December 9, 2007 by andyw

[Dream Catchers 0]

If the HZ speakers are sounding crap it is likely that the fault lies with the mixer as using the HZ you are ruling out the amp and speakers.

 

Jim