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i have been trying to choose between an svs and a sunfire sub. the sunfire is 2700 watts! is this over kill?
 

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You can never have enough power or money.:D
 

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You need to understand Hoffman's Iron Law which relates three things:


1. Efficiency (high)

2. Size (small)

3. Bass extension (low)


Physics allow you to have two. If it's small, it's either not going to play low or the efficiency will be poor.


The Sunfires are small, attempt to play low, and therefore need gobs of power. Points worth noting are that


1. You can't get 2700W out of a 15A outlet or even a 20A outlet (I don't like creative marketting)


2. Smaller drivers need more excursion to reach a given output level which increases distortion.


Tom Nousaine has a sub-woofer list with distortion (10%) limited maximum output levels measured 2 meters from a corner loaded sub. Looking up SVS and Sunfire is interesting:


SVS 20-39cs(W/300 watts)109.5dB average maximum output @ 25/31/40/50/63hz; 91dB @ 20Hz; 105.8dB @ 25Hz.


Sunfire Jr 100dB average; 95dB @ 25Hz.

Sunfire

Of course if your spouse won't let you have a big box or tube and you can't cut a hole in your theater for an infinite baffle... then you don't have much of a choice.
 

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Drew's right on point with his post.


You also have to understand that the 2700 watt figure they give is the max rating which is available for only a few seconds. The continous wattage is going to be much lower than that. Here's something you should read from the SVS faq page:
Quote:
Some subs require equalization to run strong down low, often about 6dBs below 30Hz, sometimes many times more than that! There is nothing wrong with this approach to producing good bass, but it does significantly cut effective amp power. Each 3dB boost of broad-band bass roughly halves the effective power of any given amp. So with a 6dB boost down low, a 500-watt amp acts very much like a 125-watt amp. If you are starting with a 150 watt amp? Well, you can do the math. This explains why many commercial subs need megawatts to perform well. Again, our subs run very flat to their tuning points with no equalization, (though it can be added if you want to tweak your SVS's too). In short, if you use a 300-watt amp with a CS sub you get 300 watts used, with no power spent in an effort to flatten or lower the response of the sub. Looking at this another way, if you own a sub using this much equalization you must push its driver with a full 500 watts of power (with the accompanying heat and stress on both driver and amp) to equal 125 watts with an SVS design. Needless to say 125-watt amps are relatively inexpensive and plentiful compared to 500 watt ones. And to a limited degree, the more clean power an amp can deliver the greater the bass impact. As little as 100 watts with any of our SVS CS "passive" subwoofers will drive most folks out of a room if you're so inclined! No wonder our 300 watt-ish PCi subs blow HT critics away with so "little" power.
In an enclosure as small as the Sunfire, they have to use a healthy dose of eq to get decent extension.
 
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