Side mounted woofers

[navin]

Dual side firing woofers down at the bottom do have some nice advantages, not just the form factor. Dual opposed helps with vibration (turn off one and the box will vibrate much more). The upper limit is related to driver size as they move away from omni radiation. You can probably also run it a bit higher, factoring in speaker boundary issues and bafflestep. If you cross the woofers at say 100 Hz you might find the woofers get a smoother response than the mids due to the elimination of floor bounce. You can also sort out bafflestep if your woofers run up a bit higher, potentially bringing up the system efficiency a bit. Let's say you have bafflestep coming in around 300 Hz, you can avoid any loss by using sensitive woofers and bringing them in here. It's a bit of a jugggling contest. Personally I'd bi-amp it at least, or even make it completely active, combine a MiniDSP and multi channel amp modules in one box.

My goal is to keep the system as simple as possible. Simple to build as well as operate.

The front speakers would use:
2 SB29NRX75-6 or Usher 1001B woofers (30 liters each/ F3 45-50Hz).
1 Wavecor WF152BD04 or Peerless NE149W-08
1 B&G neo 3 or Peerless NE25VTT

Another alternate is an all Morel system
2 Morel CAW938 woofers
1 Morel ECW 536
1 Morel ET448

The center speakers would be a MTM using the same 5" mid and tweeter as the front and the rear speakers would be a MT also using the same 5" mid and tweeter.

This system would be driven by a Denon 2112Ci, Onkyo 809 or Marantz 6005 or similar HT/AV Receiver (costing about $700).

The Subwoofers would be plate amp powered each using 1 Wavecor 10" woofer and 2 Passive Radiators.

 

[navin]

This system would be driven by a Denon 2112Ci, Onkyo 809 or Marantz 6005 or similar HT/AV Receiver (costing about $700).

The Subwoofers would be plate amp powered each using 1 Wavecor 10" woofer and 2 Passive Radiators.

Sorry I meant Marantz 5006. What HT/AV reciever would one recommend in the $700 range? What about Pioneer's Elite (Elite VSX-51/52) or Yamaha Avantage (A810) range? Does they compare to the Denon, Marantz, Onkyo

I really like the idea of the ones that have the Audessy Multi EQ or similar software (with microphone) but to bi-amp I'd need one that has pre amp outputs for the front channels combined with an HP filter for the internal amp so that the internal amp can be used for the 5" mid and tweeter.

Wavecor's subwoofer tuning is as follows.
Subwoofer examples

 

[Soundminded]

Does anyone here have experience in using side mounted woofers? I'm curious about how high you actually have to cross them over to get good integration, and what factors play into this.

When playing around with something like a 15" woofer, you're going to find that the front baffle gets huge. At the same time, smaller drivers don't always cut it. Putting the woofer on the side seems like a decent compromise. It also might get you a larger baffle, and thus better wavelaunch. (Depth causes less spouse aggravation than width, IME)

Obviously, the time difference will need to be compensated, and there may be other things that one will have to compensate for. I imagine lobing could get pretty weird with low order crossovers.

Anything else to keep in mind? And, again, how low does one need to cross over? I know of at least one commercial speaker that has excellent performance with a side mounted 10" woofer and a 250Hz crossover. Don't know what they've done to it, though.

Dual side firing woofers seem to have been pioneered in Teledyne AR9. This was based on Roy Allison's research. Tim Holl has an excellent explanation of the design on Classic Speaker Pages web site. The 12" AR AS woofers are crossed over at 200 hz to a front firing 8" LMR, a driver used as a woofer in AR4 series and others. How they match at the crossover frequency is part of the explanation.

The system is a kind of dual AR1W concept but the numbers don't tell the full story. The system F3 is lowered from 42 to 28 hz but is easly equalized to below audibility. That system is the most potent low frequency producer when it comes to the lowest reach with the lowest distortion I've ever heard. Literally wall shaking window rattling and gut wrenching when needed. But positioning is critical. Dayton now offers a dual 12" side firing design with its RSS315HF drivers. Should be an excellent performer and might give AR9 a run for its money.

The 200 hz crossover makes it an excellent built in subwoofer. The advantage of a 4 way system over a 3 way is obvious. I regard it as AR's concession that a 3 way doesn't quite cover the full audio spectrum. AR always had problems matching its 12" woofer to its dome midrange. The AR5which used the AR2 series 10" woofer matched the midrange better but sacrificed the deepest bass. By comparison a 2 way is a joke, there's always a hole in the FR somewhere even in most 3 ways. For this reason, most collectors of AR speakers regard Teledyne AR9 as AR's best ever, better than LST. LST incorporated 4 midranges and 4 tweers identical to AR3a but didn't have the low frequency reach AR9 does. You don't really appreciate what really deep bass does for music until you hear it and then miss it and you also aren't aware of what problems that capability reveals with other equipment. Many CDs have a lot of LF rumble that is inaudible on lesser speakers.

 

[navin]

The 200 hz crossover makes it an excellent built in subwoofer. The advantage of a 4 way system over a 3 way is obvious.

Sure but 4 ways also usually require more complex crossover design unless one goes active. One option is to get a 3 way that goes to say 45hz and use a sub for that last octave.