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perfect

alright, so as of now, my final setup would be...
head unit- http://www.sonicelectronix.com/item_6308.html
speakers- http://www.sonicelectronix.com/item_3641.html
amp- http://www.sonicelectronix.com/item_6556.html
sub- http://www.sonicelectronix.com/item_7505.html

prob. wouldnt be ordering it till late january or so, but i just wanna know about how much i'd be spending cuz im only 16...dont have the biggest budget in the world, thanks guys, decent beginner setup??

That one is a 1 ohm stable monoblock...
That's probably a very decent 750w amp, and it would still do 500w at 2 ohms - but unless you are a SQ enthusiast, I'm never one to recommend buying an amp capable of more power than you are going to use it for.

By the way, this 750w amp? Those are real watts, numbers that are meaningful. If you were to compare that amp to that Kole amp that had "1000w" boldly printed on it, those 1000w exist only in the paint. There are a lot of less reputable companies out there. That Kole amp wouldn't even do 500w RMS would be my guess, surely not the 560w that probably is the spec listed on the box.

Amps are one place where you really get what you pay for 90% of the time (with the other 10% simply being that upper-eschelon of amps that are past the simple manufacturing expense model). If you compare a $200w amp to another $200w amp, having similar feature sets, you'd find yourself within 10% of the wattage of the other, despite what you might find as wild differences in the numbers printed or painted on them.

Anyway - my point is that you need to match the impedence of the amp to the impedence of the sub, or the impedence of the sub to the impedence of the amp, depending on what you decide on or buy first.

Consider that a dual 4 ohm sub can be wired to either 2 ohms or 8 ohms.
Or that a dual 2 ohm sub can be wired to either 1 ohm or 4 ohms.
And it's important to note that if you have multiple subs - depending on how you wire them, your final impedence is affected similarly.

Consider that most all stereo amps are 2 ohm stable in stereo mode, and therefore 4 ohm stable when bridged to "mono mode".
And that some mono amps are 1 ohm stable, while others are 2 ohm stable. Hell, you might even find a 1/2 ohm stable mono amp out there here and there.
Which one you need depends on which sub or subs you have.

They have to be considered in combination.

so where it says "RMS Power (4 ohms) 325 watts X 1 chan." isnt where i should be looking?

firstly that hifonics amp at 2 ohms will have better specs such as damping factor than it will at 1 ohm.....so theoretically better control of the speaker and a better overall sound...plus at 2 ohms it matches his rms power of the sub nicely...secondly kole is actually pretty good stuff, they have fallen prey to the max power rating that so many others have but their rms is actual and is clean power.........they are an offshoot of power acoustik who also makes nice clean stuff, not audison by any stretch but not espescially noisy either....kinda like coustic was for us poor folk in the late 80's early 90's

smoker wrote:firstly that hifonics amp at 2 ohms will have better specs such as damping factor than it will at 1 ohm.....so theoretically better control of the speaker and a better overall sound...plus at 2 ohms it matches his rms power of the sub nicely...secondly kole is actually pretty good stuff, they have fallen prey to the max power rating that so many others have but their rms is actual and is clean power.........they are an offshoot of power acoustik who also makes nice clean stuff, not audison by any stretch but not espescially noisy either....kinda like coustic was for us poor folk in the late 80's early 90's

The reasons you mention are why I said

...unless you are a SQ enthusiast, I'm never one to recommend buying an amp capable of more power than you are going to use it for.

You and I could debate as to whether these things are even audible, to any trained ear you choose. Even in an A/B test.

Of course, there's another dynamic here. Does this anomoly exist in all amps? Some amps? One or two amps? Cheap amps? Expensive amps? At what point might it become audible? how audible? And to who?

Regardless, if you ranked the "potential for swing in audible sound quality" that your enclosure design affects [as you change from enclosure to enclosure] as a scale from say, 1 to 10, then by comparison you'd have to rank the "potential for swing in audible sound quality" that could be perceived by running the amp at 1 ohm instead of 2 ohms to be something like... 1 to 1.001 or so.

Of course, if you were running the amp at 500w at 2 ohms, compared to running the amp at 1 ohm but having the volume low enough so that the amp was actually only outputting 500w at that point (or having the gain control artificially throttling the amp back), then you'd have even less, or no audible difference in SQ.

Without understanding when this situation might arise, it's simply wasting money... it's buying a 1 ohm stable 750w amp , when a 2 ohm stable 500w amp is all that is needed.
...and a 750w 2 ohm stable amp is less expensive than a 1 ohm stable 750w amp... and a 500w 2 ohm stable amp of course less expensive even still (about 1/3 less, should be able to find them as easily as finding this amp).

I don't disagree that that amp won't work just fine at 2 ohms [to be compatible with a 500w dual 4 ohm sub], just that a 500w 2 ohm stable monoblock would cost significantly less - or, for the same price, a higher end amp.

Not that i havnt realized this before but i figured that i should just state it for the public....


Geoleman... you are a genius, or at least extremely smart/educated in Audio... I will have to ponder a way to beat you in Jeopardy lol

but in the real world the price of that amp is not going to be any better if it is simply 2 ohm stable vs. 1 ohm stable but you dont disagree that the performance regardless of how measurable it may be will be better therefore i think it is the better buy

smoker wrote:but in the real world the price of that amp is not going to be any better if it is simply 2 ohm stable vs. 1 ohm stable but you dont disagree that the performance regardless of how measurable it may be will be better therefore i think it is the better buy

It will, because the components in a lower impedence amp have to be capable of flowing a greater amount of current through them.

For example, an amp producing 500w through a 2 ohm load is a 31.6v AC voltage source flowing 15.8a of current through it's circuitry.
On the other hand, a 500w amp through a 1 ohm load is a 22.4v AC voltage source flowing 22.4a of current through it's circuitry.

The lower the impedence of the amp, either the amp must contain higher capacity components (that can handle more current - or the components will melt just like fuses melt ), or you need to spread the load across a more complicated circuit board using a greater quantity of components.
Both cost more money.

geolemon wrote:Yeah - impressive, all that invisible componentry, isn't it? :happy055:

You know how surface mount technology is going... ever smaller and smaller compnents...

And amp efficiency these days - all that current handled by that little doorbell transformer.

It's just Moore's Law man

I've seen head unit amplifiers with bigger/more componentry than that.