what subwoofer to use?

[eag]

I plan on making a system for an apartment I'm moving into. I want to make 2 loudspeakers for it but I have put those on hold for now. For simplicitys sake, Im gonna work on the subwoofer now.

The receiver/amp Ill have is a Sony with 2 spk outputs and a subwoofer preamp output.

I want to buy the Dayton 70W plate amp - my student budget won't let me go higher than this. One of my questions is what sub would be best to match with this? I listen to rock/ very little rap and this would be utilized mostly for movies (netflixer). I see many that I like, but there are just so many at PE that I'd like to ask those who have experience with some.

Price range would be $50 >= . I was thinking 8 or 10" . Box-wise, I'm open to any and everything.

My other question is should I think about a passive radiator? I've seen those mentioned in some projects, but I'm not sure of their effects...

TIA

[RobWells]

Bear in mind if you buy an 8 ohm woofer you'll only get about half the 70 watts from the amp.

As to woofers I have no experience with the stuff from PE, but this caught my eye on a quick browse. I haven't modelled it though.

.possible good 10"

Maybe take a gamble on a couple of cheap 12's

Or keep your eyes open for a used shiva ?


Rob

[eag]

I'm aware I'll be only getting about half at 8ohms...but if its for clairities sake thats fine. I hate indistinct bass.

[RobWells]

I've never heard of underpowering a sub to give extra clarity

I've a feeling the amp will clip easily on movie bass - not good for drivers. Depends how loud you listen though. I clipped the amp on my old mids once - 85.5dB sensitivity @ 60W (running 250Hz - 1300Hz) - the opening music of Kill Bill 1 @ reference

Have also had 900W into 3 x tempests light up the clip lights on some movie bass.(admittedly it may have been a bit over reference level )

Rob.

[RobWells]

The quatro 10" looks like a very good bet - try modelling it in winISD It has a 4ohm coil so will get all the power from the amp.

Rob

[eag]

I don't know how to use that program.

[lucio]

hi, could someone explain me what's the difference between passive subwoofer and active subwoofer?
having a passive subwoofer is a bad idea or not at all for watching movies?

[eag]

This is from PE FAQ:

What is the difference between an active and a passive subwoofer?

A passive subwoofer contains only a woofer in an enclosure with no amplification. An active subwoofer contains an on-board amplifier that will accept a low-level input and usually contains electronic crossovers. A passive subwoofer must be powered by an external amplifier and connected via speaker-level connection. Many times this passive subwoofer contains a built-in passive crossover that sends the bass to the subwoofer driver and passes the higher frequencies to the satellite speakers. This methodology is inherently difficult to implement and will usually result in very poor integration between the woofer and the satellites. Using an active subwoofer system will almost always provide superior results due to the greater control in matching output levels and matching the crossover point between the subwoofer and satellites.

[eag]

I've changed my mine a little:

I think I'll get the 100W dayton plate amp now, seeing that its on sale. I figure I can go up to $60 on the sub, which I believe I'm now looking at 4 or 8 ohm and 10".

[xstephanx]

in your situation, which is a relatively low powered subwoofer for movies. i woudl aim for efficiency, find a couple of 12" in your pricerange that have the most xmax. i know youre already stretching your budget. but moving up to a 15" dayton quatro (usually around 75$) would help ALOT. the quatro 15s fantastic drivers, tonnes of definition, good low end, and great displacement per dollar.

a 12 will generally go lower and louder than a comparable 12" driver. and will play at the same level as the 10" dirver with less THD. in your situation where eq is not an option and efficciency is key, i would definately go for a 12" design, and almost CERTAINLY ported.

the dvc 12 sounds like a good idea to me, or maybe a quatro 12" if you can afford that. keep in mind the quatro will sweep more air.

OR!

you coudl buy the cheaper 70w amp
use the money from that to buy a 15" quatro, build the proper ported box for it (5.5-6 cu ft @ 20hz via two 4" ports) and then later on move up to the 240 watt amp when you can afford it. i dont think with 15 you woudl be able to tell the difference between 70 and 100 watts, its about 1 db (aka the smallest discernable change in volume the human ear can sense). and id bet in the long run you woudl be more satisfyed doing that then just building the best you can now and then finfing out in the future that it cant keep up with your mains! just be careful with your gains and make sure the sub doesnt clip. Although id guess that even with the amp clipping alot, the quatro coudl take it.

sorry for the grammer but i just got home from school, im really not in the mood for peer editing if you catch my drift.