Class D Amplifier(s) for SWARM Subwoofer System


Hi All.  I've got a SWARM subwoofer system (4 8ohm passive subs powered by two Class A/B Dayton Audio sub amps, each amp powering a pair in series).  I've recently purchased a JL Audio CR-1 crossover, which is a true swiss army knife for integrating satellites and subs.  I am considering using the settings on the CR-1 to control the subs and using Class D amplification for the subwoofers. I'm looking for recommendations and advice on questions such as:

1) Would it be better to wire two subs in series (effective impedance 4 ohms) and drive with a single Class D channel or using four separate Class D channels and powering each sub individually?

2) The passive subs themselves do not seem to be all that efficient. So how much power should I shoot for?  (Sorry, I don't have a spec)

3) Looking for suggestions on manufactured products.  I can envision anything from a four-channel design, two stereo amps.... OR if I keep the subs in series - a single stereo amp or two monoblocks.  I know that I can get a custom 4-channel amp from D-sonic (for instance) - but I'm not up on other reasonably priced options. 

4) Am I better off building my own?  It seems like hypex is as simple as buying the components and stuffing them in a case.  (But I'm pretty busy these days, so......)

BTW - I don't want to go wild spending $$$ on subwoofer amps!  Preferably I'd like to keep the expense b/t $1k and $3k.

Thanks in advance for helpful thoughts.

peter_s

@bdgregory See the new information above.

 

So what is so special about these crown amplifiers for running subwoofers? I have only heard a crown integrated amplifier, and I was not impressed. But I am guessing this is a different class. What I need to be worried about the age of the amplifiers, and aging capacitors?

The crown is a pro amp, designed for driving PA systems. The XLS series is class d. They will drive 2 ohms no problem. I’d still run the subs in parallel. The power at 2 ohms is 775 watts/channel. The likely reason they’re popular for subs is the also have a built in crossover. I use one in my Jam studio to drive the monitors, sounds great, I also use one to drive the speakers in my living room tv system driving Totem Sttafs. Sounds great there too. They aren’t my choice for my main system, but I use one to drive my subwoofer in my home theater and it’s excellent.

 

if you’re worried about age, buy a new one ($550 I think). The used ones aren’t that old though, so it’s not an issue so long as it wasn’t abused (which some are if they are used in a pro/gigging system.

@peter_s Why not get the sub amp that Duke recommends? It works quite well (I use one in my system at home) and has the crossover built in and its far less money.

@atmasphere  Hi Ralph. Good to hear from you. I actually do have two of those Dayton amplifiers that Duke recommends. Each amplifier runs two subwoofers in series, so the effective impedance is 4 ohms. But the output is way too low to balance my 87 db efficient mains, which are driven by VAC Phi 200 monoblocks. The JL Audio CR-1 subwoofer offer has much more flexibility… Allowing me to mix RCA and balanced inputs, and outputs, allows me more flexibility for the signal balance between the mains and the subs, and has all the controls on the Dayton amplifiers as well. This will help me greatly as I try different equipment, its universality.  it will also allow me to use some more powerful amp, and hopefully get a better SPL balance between the two, so I think it is a win all around. I have the CR-1 on the way.  Make sense?

@peter_s I'm puzzled why the sub output is so low. My main speakers are 98dB and the Daytons with the Swarms have no troubles keeping up. With the limited power you have with the VAC and the 87dB of your speakers, this should be a walk in the park for the subs and amps. So I think you have a setup problem or an outright malfunction.

BTW I don't think the Dayton puts the subs in series- they are parallel for a load of 4 Ohms. I use a set of Jensen subwoofer transformers to convert from the balanced output of my preamp to the single-ended input of the sub amp. Works a treat.