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the 4 ohm rating

im a little confused as to why buyers choose 4 ohm products.

now here's what got me thinking about all of this 4 ohm stuff.

i took a pair of mids into my rebuilders shop the other day to get new surrounds installed & we started talikng audio & he told me that about 75% of the blown driver's he takes in for rebuilding are 4 ohms & the other 25% was split between 8 & 16 ohms.

correct me if im wrong but when you run a amp in 4 ohms as opposed to 8 ohms isnt the amp working much harder to produce the inflated wattage at the lower ohms? & isnt a amp thats getting worked hard a bad thing?

the same goes for 4 ohm speakers,the 4 ohm rating only makes the speakers to appear to be more efficient & also creates the need for thicker cabeling for the lower ohm's.

i hope the answers can remain civil as i didnt start this thread to be a smart ass but i am wondering what(if any)advantages there are to having 4 ohm gear over 8 ohm gear.

take me to school here & learn me somthing because all im seeing is drawback's to owning 4 ohm gear.

mike.
128x128bigjoe
xiekitchen
821 posts
 
Ran Spica TC-50's for over a decade with 3 different amps never a problem at 4 ohms.
Now using (the most inefficient speakers I've ever had)Chario Academy 1's at 4 ohms, not a problem at all and not hurting my amp (Eagle 4) at all.
autio
42 posts
 
Here is what one speaker designer has to say about designing 4 ohm speakers
"Thiel speakers have long suffered a reputation for being power hungry. Jim Thiel admitted that most of his speakers sport 86-87dB sensitivities and are 4-ohm loads. He could easily transform them into 8-ohm loads, but he prefers to avoid the concomitant loss of sensitivity by 3dB. He also uses 4-ohm loading since most well-designed solid-state amplifiers will double their output power into such loads. Why purchase this amp capability only to leave it unused?"

taken from http://www.soundstage.com/yfiles/yfiles200107.htm
sirspeedy70680e509
1,064 posts
 
Even if your amp can drive a more demanding load it will still work a bit harder doing so,as compared to an easier one.Think 4 cylinder vs 6 cylinder engines.The fact is that the internal circuitry will still run cooler on an easier load,and common sense dictates that there has to be a sonic advantage to doing so.
jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
sirspeedy, even a Class A biased amp? My amp seems to run hot no matter what's connected to it. I think in my case it's just a matter of whether the energy is being used for musical purposes, or dissapated as heat.
Using your car analogy, my car (amp) runs pedal to the metal all the time. It's just a matter of if the wheels touch the ground and transport me somewhere, or simply races the engine, if the transmission is placed in park while maitaining with the pedal to the floor.
I can understand your reference regarding a Class A/B designed amp, I don't know that this is the case with a Class A biased amp.
gregm
3,396 posts
 
To use Jc's analogy above, class A runs pedal to the metal all the time (i.e., it's class A). It won't get cooler or hotter unless the ambient temperature plays tricks...
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