blown voice coil? [Archive]

shawn earnheart

01-14-2007, 03:23 PM

I think i have a blown voice coil. This is my system: X590 Kenwood Head Unit, MRP-F240 Alpine Amp in bridge mode (100W x 2 RMS 360 x 2 peak) hooked to db 6500 component Polks in my front doors and db 460 in rear pillar running off the head unit only. System started cutting out when balance was set to 0. I can put the balance on the right side and everything is fine. So I swapped speaker outputs on the amp, problem stayed on the left side. Would like to know what would cause this to happen, did I just get a bum speaker? Also, what are my options, can I just buy a replacement speaker?

MacLeod

01-14-2007, 06:16 PM

Are both left speakers cutting out?

shawn earnheart

01-14-2007, 06:24 PM

no. i had speaker checked at radio shack its blown also hooked up another speaker i had and it works fine.

MacLeod

01-14-2007, 06:37 PM

Well that was easy. Glad I could help! :p

shawn earnheart

01-14-2007, 06:44 PM

thanks. but what about buying a replacement speaker,is that something that polk offers?

MacLeod

01-14-2007, 07:50 PM

If you bought them thru an authorized dealer and not off of Ebay or fly by night dealer, they may be under warranty.

Give Polk CS a call and they can help you more.

Customer Service:
polkcs@polkaudio.com
9am - 6pm, M-F, EST (USA)
800-377-7655 toll free phone
410-764-5470 fax

Eiderlon

01-25-2007, 09:56 PM

Blown VCs are more often caused by distortion and clipping than by pure overpower conditions.

MacLeod

01-25-2007, 11:47 PM

Voice coils are fried only when more heat is built up in them than they can dissipate. The only way for this to happen is by overpowering. The reason why clipping is associated with fried speakers is because when an amp clips, it sends out a signal at a wattage limted only by input voltage which is usually double its normal output. And if this increase in power is more than the VC can handle, it fries.

Distortion is not something that can hurt a speaker. It is merely a symptom of the speaker being overpowered or the amp being overdriven. My favorite analogy is a gun. If I shoot you, will you be injured by the bullet or the loud bang? The distortion is the bang. The overpowering is the bullet.