RS225 on an open baffle with a plate amp

[brianpowers27]

I would love to simulate what I am about to desribe but I am not sure that any tools will allow for this.

I was wondering whether or not this could cross over to a rs150 with the help of a plate amp. (Dayton subwoofer 240 watt with boost)

--I would like to place two rs225s-8 woofer in paralell on an open baffle/h frame.
--One or both of the woofers may rely on the floor boundary
--I could use the plate amps rolloff to compensate for the open baffle loss

[Russ_L]

Linkwitz Labs

Brian- Linkwitz Labs has a very nice dipole subwoofer design http://www.linkwitzlab.com/woofer.htm that may give you some insight to your quest.

Russ

[AJINFLA]

I would love to simulate what I am about to desribe but I am not sure that any tools will allow for this.

JohnK or MJK software. Neither free, nor expensive.

I was wondering whether or not this could cross over to a rs150 with the help of a plate amp. (Dayton subwoofer 240 watt with boost)

RS150 sealed yes, dipole no.

--I would like to place two rs225s-8 woofer in paralell on an open baffle/h frame.
--One or both of the woofers may rely on the floor boundary
--I could use the plate amps rolloff to compensate for the open baffle loss

What's stopping you? :W . You would also have to use the lowpass to counter the roll off/peaking. Do keep in mind that the volume displacement of the (2) drivers is still limited, probably too much so for dipole use, IMHO.

cheers,

AJ

[brianpowers27]

I was afraid to hear the obvious. Displacement limitation. I have $250 PE bucks burning a hole in my pocket.

I kind of like the idea of the bipole arrangement that I have been throwing around. THis should improve the interaction of the room by creating peaks to the side.

P.S. I would love to go burn through a ton of MDf, but my budget is tight right now./

[BobEllis]

Add a bit more to your PE bucks and try http://www.audioheuristics.org/curre.../whats_new.htm It's 4 x RS225 and 27TBFCG dipole.

The down side of dipoles is that you need lots of displacement to get bass. The good side is that the dipole above was cleaner at the bottom than the RS225/RS28 box.

Edit: 2 x RS225 would either limit your bass extension or if you've got a bass bin you could use, cross it at 200 Hz or so.

[brianpowers27]

Add a bit more to your PE bucks and try http://www.audioheuristics.org/curre.../whats_new.htm It's 4 x RS225 and 27TBFCG dipole.

The down side of dipoles is that you need lots of displacement to get bass. The good side is that the dipole above was cleaner at the bottom than the RS225/RS28 box.

Edit: 2 x RS225 would either limit your bass extension or if you've got a bass bin you could use, cross it at 200 Hz or so.

I have to say that I would love to build that. I think that I am gun-shy, regarding the active electronics and required multi-channel amp.

[sfdoddsy]

Aside from the displacement issue, the bass boost of the plate amp won't be anywhere near enough to compensate for the dipole roll-off.

You need either a really big frame or lots of displacement, and you will still need to EQ.

It is, however, worth it.

[JonP]

I was afraid to hear the obvious. Displacement limitation. I have $250 PE bucks burning a hole in my pocket.

Go bigger, longer... say two RSS265's. :B You could almost go two RSS315's, but that leaves nothing for amps and other stuff... Guess the 265's won't leave much either.

Actually, if you want more of a prototype, you could go with some cheaper drivers, but you are up against that volume displacement requirement. They need area and Xmax... Sigfried and maybe John K have some Excel calculators to figure where that is for box and dipole use, might be handy to evaluate drivers.

And, if it really is going to be a dipole (or similar) you will need that dipole EQ. I've been playing with a bit of active EQ stuff lately, could give you a hand perhaps... Not all that bad if you've built a thing or two, not all that bad if you haven't, that kind of filter isn't all that complicated. Sigfried's site will show you what you're up against... just don't look at a whole Orion crossover and freak out, OK? 8O

[Landroval]

You might want to take a look at Hypex's AS2.100 which is a 2x100W UcD plate amp. It has a built in DSP that can be fully controlled with a PC through a USB connection. Makes active EQ for e.g. OB's much much easier.

http://www.hypex.nl/

[brianpowers27]

I forgot to mention.

--I have done one dipole in the past.
--I already have these drivers (got a fantastic deal on them)
--I would love to do something truely active for the xo but I am not ready to learn right now.
--I may turn this project into ob mids + monopole tweet/woofers. (haven't done one yet.)