Need 2000W rms at 4 Ohms - Suggestions?

[Ramblin 10+ year member]

Mcsoul, bear with me here, as I am a self-confessed (and humble) noob. Can I run 1 ohm and get good sound quality, as defined by a high damping factor? I don't want a lot of mush. I would guess that all amps are different and there are some that can put out good SQ at 1 ohm. Am I off-track in my desire to run at 4 ohms? Or at a minimum 2 ohms?

Let me put it another way, will the SQ at 4 ohms be better than at 1 ohm?

Am I putting too much emphasis on damping factor?

 

[mcsoul 10+ year member]

Provided you pick a quality product it will sound great (1 ohm class D sub amp).

Damping factor is not like horse power where more is good and even more is better.

You only need what's necessary to get the job done and the number is actually quite

low. There are a few threads on the topic. Like I said, a used sundown SAZ 1500 would

be a great choice, most go for about $325 shipped and I would use that as the quality/price

starting point for 1800w@1ohm (or 4ohm). You can find cheaper, but how good is it, you can find

better but how much better and at what cost.

 

[gunz4me 10+ year member]

Let me put it another way, will the SQ at 4 ohms be better than at 1 ohm?

Am I putting too much emphasis on damping factor?

Unfortunately, SQ is subjective and you are trying to pick out an arbitrary number in the frequency range where the human ear is the least sensitive. IIRC, in testing, I think most subjects couldn't determine damping factor until it was in the 50 to 100 range. Also, in the past, certain amplifier manufacturers claimed ultra high damping factors @ 4 ohms by measuring it at the circuit board, NOT the actual speaker connectors.

Another argument about damping factor, which is generally defined as the amplifier controlling the movement of the speaker, is that with modern subwoofer suspensions, one no longer needs a high damping factor. In other words, the spyder on the subwoofer combined with its surround can generally keep the subwoofer in check should things get a little wild from the amplifier's output.

With regards to SQ, there is one argument that comes over from the pro audio world that one will generally have slightly higher SQ at 4 ohms versus 1 ohm. The reasoning being is that many class D amplifiers tend to VI limit themselves out the wazoo at 1 ohm whereas at 4 ohms they don't have to VI limit as much due to the fact that the amplifier isn't working as hard.

Sadly, SQ is subjective and your install will play a bigger part in determining your SQ than your choice of subwoofer amplifier (ETA: or the final impedance of the monoblock). Another downside against JL Audio subwoofers is that JL Audio tends to give bogus enclosure sizes thus requiring one to build a larger than usual enclosure to achieve decent sub bass output from them. In other words, .75 cubic feet per 10 may not be enough because I found my 10w3v2s to sound better in 2.5 cubic feet sealed for the pair versus running each 10 in .75 cubic feet sealed. If the w3v3 series is anything like its predecessor, you will need more enclosure space to get a decent bottom end. In looking at JL Audio's specs, you will have a F3 response at near 50 Hz if you follow their recommendations. In a larger, open air SUV, this may be enough to get a decent low frequency extension due to the transfer function, or cabin gain as it is known. In an extended cab pickup truck, you may find the subwoofer to be a tad bit boomy by placing all four 10s in 3 cubic feet of airspace.

Of course, your mileage may vary.