Dual RS225-8 Fast
Hello X,
You once wrote in this thread, in a reply to Jessman, "Another option is to use dual RS225-8 in parallel (in 50L box) and then decrease padding on tweeter."
Could you detail how this would be done or point me to a post that explains it?
I'm assuming 50L sealed box, no seal between woofer compartment and 10F compartment, dagger behind 10F, less padding on 10F (to up the output of the 10F?)
10F on bottom still? Modifications to XO? Expected FR? Still transient perfect? Anything else?
I've also got this dream for the FAST Mini Sovereign WMTMW, recessed tweet with felt. Seems appropriate as I'm a native of Wichita, KS -- birthplace of John Dunlavy. But that's for another day. Thank you for all your efforts.
Hello X,
You once wrote in this thread, in a reply to Jessman, "Another option is to use dual RS225-8 in parallel (in 50L box) and then decrease padding on tweeter."
Could you detail how this would be done or point me to a post that explains it?
I'm assuming 50L sealed box, no seal between woofer compartment and 10F compartment, dagger behind 10F, less padding on 10F (to up the output of the 10F?)
10F on bottom still? Modifications to XO? Expected FR? Still transient perfect? Anything else?
I've also got this dream for the FAST Mini Sovereign WMTMW, recessed tweet with felt. Seems appropriate as I'm a native of Wichita, KS -- birthplace of John Dunlavy. But that's for another day. Thank you for all your efforts.
I would put the RS225-8 in parallel (4ohms) front and back in a bipole and that gets you 93dB sensitivity at 2.83v since no baffle step loss. Use a higher sensitivity full range like a 3FE22 for 91dB. The XO would have to be reworked but still first order and now 4ohms. Probably 2mH inductor for the parallel woofers. Woofers still on top.
If you made a box with fullrange in stepped baffle (3in setback) you could do WFW config. Only 88dB in this case.
If you made a box with fullrange in stepped baffle (3in setback) you could do WFW config. Only 88dB in this case.
Loving mine sofar. Finally found a use for the 10 RS225-4 sitting in a box. Sorta wish I would have done a Bipole like your talking about, but at least this way I can make my entire theater outta these speakers. I set mine as all images ive seen suggest to 7.5" apart. Mine are just in test box's so nothing fancy to show, but loving them. I screwed up my math(happens a lot) and made them 2" shy in depth. Mine turned out to be 16"H 10"W 10"D, and even after adding a small back to seal the RS100- they still sound great and kick out a lot of bass for sealed. Ran AUdyssey and its seeing them as Full Range. Adding a good amount of polyfill to dampen them and sorta hold the XO to the bottom lol.
This bipole arrangement intrigues me. That’s a huge increase in sensitivity. It could even be done as a TL. The current TL has a 180 deg turn at the top and a driver could be placed front and back. Dimensions would need to be reworked but doubling drivers with same volume might still work. Let me run simulation and see.
To use RS225-4 in bipole, they would be wired series for 8ohm unless you had a 2ohm capable amp. Here, no boost in sensitivity but bipole eliminates 5dB baffle step and overall is 88dB. 10F would be used straight no attenuator resistor.
To use RS225-4 in bipole, they would be wired series for 8ohm unless you had a 2ohm capable amp. Here, no boost in sensitivity but bipole eliminates 5dB baffle step and overall is 88dB. 10F would be used straight no attenuator resistor.
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Initial sims of dual RS225-8 in parallel and bipole seems to show only 86.8dB at 2.83v and 1m. But this is after baffle step so still very good. Looks like the 10F sensitivity is still going to be ideal with minimal attentuation. However, there is a dip at 415Hz - probably 1/2-wave cancellation between the Rear membranes of the front and back drivers. Lots of stuffing there could reduce that in practice. But an 86.8dB sensitive speaker is very nice. I had to increase speaker internal width to 10.5in for extents baffle at 12in wide external. -3dB is at 32Hz. Great extension.
Woah... shipping a couple of RS225 to Singapore is not so cheap!
So, this new TL design is international now.... cool.
PE shipped a pair to Dhaka via UPS for only $55. The customs duties is another thing though. I imagine Singapore is similarly priced?
I guess I forgot to mention that a RS225 FAST TL (probably with B80) will be born in Dhaka soon.
Two more pairs are being built in the Seattle area. I don’t think those are as far along though.
I think the crossover board makes things easier and certainly the plans seem easy enough to make.
I guess I forgot to mention that a RS225 FAST TL (probably with B80) will be born in Dhaka soon.
Two more pairs are being built in the Seattle area. I don’t think those are as far along though.
I think the crossover board makes things easier and certainly the plans seem easy enough to make.
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Please be kind, my first time trying to build a speaker set.
Made some mistakes along the way, as we use mm instead of inch for measurements.
Thanks, X for helping along the way.
Awaiting X's xo pcbs....
Pic shown are plywoods being line up for fitting, not glue yet.
Shipping costs for those drivers and mid were expensive to SG. Mostly due to the weight.