Woofer replacement help

Evanv99

New Member
Apologies if something has been posted likenthis already but I couldn't find it, but I am fairly new to all this , i have a set of xfinity sm 155s powered by a forte model 3 , I have heard that you get more power running 4 ohm speakers , and I blew the woofers on the 155s , so I am looking for replacement speakers ,and was wondering if I should replace with 8 ohm or 4 ohm ?

Thanks
 
If you look for direct replacements (ie, woofers pulled from other identical models), you shouldn't have to worry about impedance. They will be correct.
 
Any recommendations on other speakers?
Craigslist is a great place to look for great used speakers. What vicinity do you live? A quick search can pull up a few possibilities. What are you looking to spend? What type of music do you listen to? Every speaker is different and can do some things well, other things not. Otherwise you will get a bunch of answers from people about what they like and you may never find, or afford such.
 
Craigslist is a great place to look for great used speakers. What vicinity do you live? A quick search can pull up a few possibilities. What are you looking to spend? What type of music do you listen to? Every speaker is different and can do some things well, other things not. Otherwise you will get a bunch of answers from people about what they like and you may never find, or afford such.

I live in the Detroit area , I listen to alot but mostly metal ,so anything that can handle loud and fast ahaha ,
 
I would have to agree that the SM series was by no means one of Infinity's finest efforts, and probably not worth repairing. If you are looking for loud, fast and "in your face" sound on a $300 or so budget, I'd be looking at CV's and JBL's.
 
For replacement woofers you would want to get drivers of same impedance and efficiency or it won't sound right. Impedance to match with crossover and efficiency to match sound levels with mids and tweets. Probably not an easy task as those speakers are very efficient. Since you've ordered them already I guess it's plug, play and see what you get.

I have a friend here on AK who has speakers out the wazoo of all brands and costs (collector nut job) and he says the SM155's sound damn good with tube power. Many here who bash the quality of items have never heard said item and have become parrots repeating what they have heard on the net, so take the feedback with a grain of salt!
 
Thanks I ended up ordering some cheap replacements, and still going to Keep an eye out for an upgrad set of cv as suggested , I somehow have a talent for destroying speakers
Sounds like a plan, once you have them up and running give the new woofers a chance to break in before passing judgement on how they sound
That means playing the speakers at low to moderate volume for awhile (several hours at least) before turning them up.
Also, be careful about over-driving your amplifier (usually by trying to push more bass or high volumes) as that is what typically blows speakers.
It takes lots of clean, low distortion wattage to drive speakers to higher volumes without destroying them LOL
 
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Try to keep volume moderate, We all like to crank it up, Or use too. But you can only go as far as the rig will allow. When distortion shows up, Back it off a few clicks. Like most of us, You will eventually get the gear to reach stupid loud spl's, But then you have hearing issues to force lower volumes again! What is your amp/receiver? Good luck with the repairs.
 
Overdriving an amp is a sure way to kill speakers. What happens is the amp will hit is's maximum power output, but the input will demand still more power. The amp cannot deliver it and so is driven into a distortion called clipping. This produces a very great deal of high power harmonics that sound terrible and generate heat in the voice coils of the speaker, leading to failures. Tweeters are usually the first to go but woofers can fail in this way as well. This can be made even worse by the fact that some recordings were pushed to too high a level during mastering, causing clipping in the recorded music. Heavy Metal recordings can do that quite a lot. So if you take a recording that already has those harmonics in it from the recording process and run it through an amp set so high it starts clipping, you are getting the same effect but on steroids. Not good for speaker longevity.

Shelly_D
 
In the original post you say you blew the woofers. Can you describe in more detail the symptom. Did the surrounds crumble or do the woofers make a scratchy sound. Possibly they are easily repairable by none other than yourself with a little bit of help from this forum and youtube. Then you'd be up and rockin again!
 
Typically just overdriving an amp will result in fried mids or tweeters. Blowing woofers suggests maybe the bass has been cranked up and/or loudness is on. This is a recipe for frying an amp as well as blowing woofers.

What's the point of having a stereo, you ask? Well you need to have the equipment to do what you want to do. Otherwise it's like taking a Ford Fiesta to the race track and blowing the engine, then asking why you can't drive it 200 mph. :biggrin:

And it's not about getting a 'better' plastic piece of junk at the WalMart that says on the box it puts out 5000 watts. Suuure...for a second, when lightning strikes it. :biggrin:

Having said all that, I would echo the advice to take it easy and look after your hearing. You can still have fun without damaging it.

I'm not sure you posted what you are driving these speakers with, perhaps we can advise.

Woofers interact with the cabinet and crossover quite a bit, so it's unlikely that a given woofer, purchased based mainly on its price, will be the best one or will sound like the original.
 
In the original post you say you blew the woofers. Can you describe in more detail the symptom. Did the surrounds crumble or do the woofers make a scratchy sound. Possibly they are easily repairable by none other than yourself with a little bit of help from this forum and youtube. Then you'd be up and rockin again!

You need to be more analytical. "Blew the woofers" is mostly meaningless.
 
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