WTB dirt cheap subs that handle 1500rms alone or as pair. I'll take anything

[thisisausername 10+ year member]

These are for a frat house so cosmetic stuff doesn't matter.We bought a 1500w rms amplifier that is not underrated at all. Unfortunately we incinerated our existing subs with it and now we are broke. Needs to be cheap, like under 200 bucks. It's stationary installation so box/driver size have no limits.

Give me your re-cones and weird oddball prototype custom ****!

• needs to be a four ohm load to the amp. How you get there doesn't matter
  
• high efficiency/bigger drivers would be nice
  
• has to function
  

I'm near chicago I can pick up if you're local

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[MXcarAudio]

thanks! Didn't know about that company, seems like they make decent stuff tho. If nobody offers up used stuff I'll probably go with that

they used to be AQ and very good subwoofers

 

[SamIam71]

yeah unfortunately 120v audio stuff is usually more expensive than car audio //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif . Not totally sure but I think I know a reason. I've done a good bit of research into switching power supplies, it was for an inverter based welder but principle is the same. Inside the amp you have a Power Factor Corrector before the main switching stage and, at least for me, that ended up being far more expensive to build than the switching part itself. To spare the details the PFC stage is used because with AC current, a switching supply without one would only draw power from the peaks of the wave. This would distort the mains power circuit really bad and also puts tons of pressure on the capacitors and rectifier for the main stage. I read that most class D mains amps can only provide their RMS rating for about 20ms then they drop down to about half power. 20 ms is coincidentally about how long it would take to drain the stored energy in the PFC stage if it was designed to handle about half the rated power.
The relevance of that rant is that since cars use DC they don't need a power factor correction stage at all. That effectively eliminates the first half of a regular mains amp. 12V is also a really friendly voltage for IC's and micros so you also save by not having a separate power supply to run the main amplifiers switches and such.

You make is sound groovy, but this is 30+ year old technology, that much clean power can be bought for less that half the price. Also, switching power supplies in car audio amps has been the standard for about as long. I remember seeing mosfet power supplies in the 80's. Good luck finding what you need man.

 

[SamIam71]

Cerwin Vega Stroker Subwoofer | eBay

 

[michaellane 5,000+ posts]

stereo integrity HT 18 $239 shipped from factory brand new

 

[thisisausername 10+ year member]

soundqubed hds300 dvc2 15's $150 shipped, one should handle 1500rms
SoundQubed HDS315

or 2 hds200d vc4 15's $89 each

SoundQubed HDS315

After looking around for days I couldn't find any better for my application than these. The company designs them with big boxes in mind, which is great since I have basically unlimited size avail.

I just ordered two HDS215 15" subs. Thanks a lot!

 

[thisisausername 10+ year member]

You make is sound groovy, but this is 30+ year old technology, that much clean power can be bought for less that half the price. Also, switching power supplies in car audio amps has been the standard for about as long. I remember seeing mosfet power supplies in the 80's. Good luck finding what you need man.

I think my rant was a little nonsensical because I was quite drunk at the time. My main point was that amplifiers are more expensive to design and build for 120V AC mains than they are for 12v DC . Power Factor Correctors (PFC's) must be used with high power AC amplifiers because otherwise you will distort the sine wave in the power circuit and perhaps the entire building with what looks like clipping. 12V car stuff doesn't need any of that because its already DC.

Also, most amplifiers for Professional Audio are Class-D and full range (up to 20khz). Until recently Class-D amps were mostly for subwoofer use in car audio. Building full range Class-D amps is harder and more expensive. The switching frequency must be high enough that harmonics will not affect audio quality at higher frequencies. This requires a switching speed of 100+khz which was hard to do until recently. You are right that mosfet amps have been around for a long time, but regular mosfet amps are Class A/B which is only ~45% efficient at converting power input to audio output.

 

[MXcarAudio]

After looking around for days I couldn't find any better for my application than these. The company designs them with big boxes in mind, which is great since I have basically unlimited size avail.
I just ordered two HDS215 15" subs. Thanks a lot!

Hard to beat the price