Eminence NSW6021 21" sub users - which amp are you using?

Your current amp ;)

Run it at the 1v setting. You won't know what it has until you redline it.

It's like driving a Corvette exclusively during rush hour then wanting a Bugatti for more top speed...you have to give the Corvette some track before you really know what you're working with.

You should easily be able achieve over 125db at 1 meter with the XLS2502.
 
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Subw00er

Member
2020-10-16 9:34 pm
I returned the 2502. I am using a 1000w HT amp atm.

Ernie, I used to track a corvette, so I understand your analogy. I never passed a Bugatti, but I passed my fair share of Ferraris and Porsches. :) BTW, I was hitting 125db at 3+ meters with the 2502 at all sub frequencies. It just sounded like a turd. :)

Ok, I will try this. I didnt know if there was some nuance to rca vs balanced and the setting..didnt want to hurt my amp.
 
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You returned the XLS as fast as you race :)

Won't change a thing if you're happy with the current spl levels. Would've been interesting to compare the 2502 to your HT amp.

You would gain roughly 6db of output potential over the 1000w amp. That's a noticeable amount when the occasion comes up.
 
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Subw00er

Member
2020-10-16 9:34 pm
Yah I hear guitar center filed chapter 11 so I returned it the next day before they stopped taking returns.

Thats really surprising. So in my HT/audiophile class A/B world, if a speaker is struggling a bit, you give it more power with an amp that has big caps and transformers/headroom, and it generally (always?!) makes the speaker sound a lot better.. But in the D class pro audio world, this logic does not follow suit? Is it something about the way a d class amp delivers power, or because its a big sub?
 

wg_ski

Member
2007-10-10 5:21 pm
The old iron core transformer power supplies don’t have any mechanism to limit the current that is delivered - you can exceed its rating by a factor of 10 and nothing cares, as long as long term heating is not too much. Switch mode supplies have hard limits (and sometimes soft limits). The problem with them is that it’s sickeningly easy to hit those limits. In most “prosumer” switchmode amps, that limit is set to the AVERAGE current demand, and happens in milliseconds. But at subwoofer frequencies you could require up to three times that amount (do the match, it’s true, there is a factor of Pi), for many milliseconds at a time. The cheaper amps will limit, and put out less power at low frequencies. The expensive touring grade amps won’t, and that’s why they’re expensive. The supplies are beefy enough to handle these 3X peaks safely without limiting early or exploding. They do have longer term limits, but the time constants are long enough to reproduce a kick drum at full power clipping. At infra-sonic frequencies you may still run into theses limits even with the best amps, but it will be better than with a cheap Crown.
 
Yah I hear guitar center filed chapter 11 so I returned it the next day before they stopped taking returns.

Thats really surprising. So in my HT/audiophile class A/B world, if a speaker is struggling a bit, you give it more power with an amp that has big caps and transformers/headroom, and it generally (always?!) makes the speaker sound a lot better.. But in the D class pro audio world, this logic does not follow suit? Is it something about the way a d class amp delivers power, or because its a big sub?

If the speaker appears to be struggling, and a larger amp fixes that, then the problem was not the speaker. Chances are the amplifier was running out of power.

Bigger amps don't magically make speakers act more linearly.


The thing to remember here is you've got a top-end 21" PA subwoofer. If you want to be able to run it up to its limits, you're going to need a big amplifier.

In terms of optimising sound quality, any decent solid-state amplifier will do the job until you reach the limits.


My suggestion would be this: instead of spending over a thousand dollars on a new amplifier, spend around $100 and buy a Behringer ECM8000, a UMC202HD, an XLR cable and a mic stand. Do some acoustic measurements, and figure out what's actually wrong with your setup.

Swapping one half-decent amp for another is not the answer here.

Chris

PS - The Crown MA9000i above is an excellent amplifier, but fan noise will be a problem for you.