View Single Post
Old 06-30-07, 04:46 AM   #7
Redeemed
Registered User
 
Join Date: May 2005
Posts: 17,982
Default Re: Thinking of selling some speakers...

Quote:
Originally Posted by Tr1cK
I just didn't think you would get much for the LXIs.

Anywho, you have to match the ohm load to the system. If it's an 8 ohm stereo then your total impedance from the speakers needs to equal that. A regular old multimeter is a good device to check ohm loads. You also must watch how you wire the speakers together as to not throw the ohm load off.

Two 8 ohm woofers wired in parallel together actually is a 4 ohm load, if you wire them in series, you will make it a 16 ohm load. The same goes for 4 ohm woofers...wired in parallel will produce 2 ohms, wired in series will produce 8 ohms. This is a trick amp makers use to produce more power. If you put a lower ohm load on the amplifier, it will output more power because of less resistance. You just have to make sure you amplifier is rated for it or risk a chance of something frying.
That is some awesome info dude- thanks so much. For the longest time Ohms has actually had me confused. Okay, since you mentioned it, could I get some more info from ya'? Here goes:

This is my center speaker that I've been using for several years now-



That is actually a truck speaker box- with two speaker-wire terminals (one per-side). If you look close enough, you can actually see speaker wire coming out of either side. I have the speaker wire feeding into the center speaker output on my reciever. Since that box is rated at 300 watts/ 4-ohm load, and my reciever outputs 100 watts/8-ohm, I just assumed to never pump more than 75-watts to that speaker since it is recieving at 8-ohm signal. So far I've had zero issues, and there have been many times when I've had this system cranked way up, never any popping, gurgling or any other form of distortion or reason for concern. Was I wrong in my assumption? Is my amp actually going to be pumping out more to that speaker than the rest? No where in the manual does it say anything about my reciever being able to handle anything other than an 8-ohm signal- would that be to prevent confusion for noobs like me? My reciever is far from top of the line:

(currently the equalizer seen here is not in use)


As to the LXI's, I know I wont be getting much, but I'd just like to know what the "experts" here think I could get for them- at best, and at worst. I was figuring anywhere from $25-$50 per speaker. Does that seem too high? I couldn't fathom $50 for the pair being too steep, these are still awesome speakers for anybody that doesn't mind their size and limit of 100-watts power handling.

Quote:
Originally Posted by Tr1ck
Two 8 ohm woofers wired in parallel together actually is a 4 ohm load, if you wire them in series, you will make it a 16 ohm load. The same goes for 4 ohm woofers...wired in parallel will produce 2 ohms, wired in series will produce 8 ohms. This is a trick amp makers use to produce more power. If you put a lower ohm load on the amplifier, it will output more power because of less resistance. You just have to make sure you amplifier is rated for it or risk a chance of something frying.
So... let me ask you:

The speakers that will be replacing my LXI's- right now it is just a 15" woofer per box, rated at 300 watts max, 150 watts RMS, 8-ohm load. What would happen if I wired (in a series) two 4-ohm car speakers (a tweeter and a full-range) to the 8-ohm woofer- would that make it 16 ohm all together (or would the 8-ohm woofer cancel it all out and make it 4-ohm again)? Thus meaning more resistance (if it would creat a 16-ohm load) causing the amp to work harder to pump out is rated wattage, correct? Could I device my own "Crossover", where the woofer gets its own signal, not being directly connected to the car speakers, but then having the two car speakers connected together in a series to form an 8-ohm load, and then running the two car speakers in parallel to the woofer? Would that work?

Okay, originally I got these speakers from Radio Shack... several years ago. Radio Shack no longer sells speakers like these. So that is why I need to find an alternate source for the two midranges and tweeters (one midrange and tweeter per box).

To clarify how my setup is currently-

I have the two LXI's I'm wanting to sell hooked up to the reciever I posted a pic of above, they are being used as my "front" speakers. That truck speaker is my "center" speaker, and then I have two 4-way tower speakers as my "surrounds" (If you want a picture of both of these tower speakers just let me know, currently I only have a pic of this one):



Those "5" (I put 5 in quotes cause my center speaker is actually two but I have it wired as 1) speakers are running through the 5.1ch surround sound reciever I posted the pic of above. For my subs, I'm using those the 15's I posted pics of earlier. I have two of those Fisher boxes, each having a single 15" woofer. I have both of those hooked up to this amp:



That amp is connected to the sub pre-out on my 5.1 channel reciever. I have the treble turned down, the bass up, and the loudness on. Unfortunately, that amp is no longer working- which considering that I've had it since I was about 14 (I'm 20 now), and would regularly have my music, games, and movies playing extremely loud- it was just a matter of time before it went. It did 130 watts x2 @ 8-ohm. Since each 15" was rated at 150 watts RMS that seemed to be the perfect combination (that amp plus those speakers). Overall, this setup has worked unbelievably well. It will easily drown out the $600 sound system I have in the living room, even with all the doors between my bedroom and the living room closed. No, I haven't had any neighbors complain yet- the neighbors to our left ocassionaly blares rock n roll, and the neighbor to our right is is a stock car racer. So this neighborhood is accustomed to loud noises.

Anyhow, thanks again for all your input- I really do appreciate it.

Quote:
Originally Posted by AlphaWolf_HK
How much did you spend on the new speakers? And btw is this for an HTPC?
Not a whole lot actually. The two Fisher speaker boxes I bought for only $20, and the two 15's I bought for like $80 about 4 years ago. The two 4-way towers I'm running as my surrounds were just given to me by a friend. I replaced the mid-ranges with some from Radio Shack (about $60 for the both of them), and then the 12" woofers I replaced with two from RadioShack (about $75 for both of them). Out of all my speakers, I love my two towers the most. Those things are relentless. They'll kick like a mule and keep begging for more. I'm not sure if the wattage rating on the speaker box refers to just the speaker's or crossover's maximal load- but so far I've pumped a continues 130watts to each one, not a single pop or hint of distortion. My buddy was over and dared me to try it, I did, and even side by side yelling at each other we still couldn't here one another. These things put out so much boom it rattled the cover for my bedroom light off (it was glass, and just screwed in), as well as rattling the vents in all the bedrooms loose. I don't think I'll ever part with these tower speakers. I'd give up my computer before these beauties.

And it isn't for an HTPC per-se. I do have it hooked up for my computer, which is what I use for gaming, movies, music- everything. That is why you do not see a cassette deck or CD-changer- I have no need for either. So, I guess that in a way it is for HTPC, sort of.
Redeemed is offline   Reply With Quote