Infinity IRS V Clones

I've already build a pair of line array speakers similar to Roger Russell's IDS-25's and it's recently occurred to me that it's not completely out of reach to build a pair of Infinity IRS V speakers (not including the base towers). Instead of the drivers used in the original, I could use the Peerless TC9's that I already have experience with.

For the woodworking, I could make kurf cuts along the length and make a form to bend it over. I would finish it in white like my previous line arrays, so it doesn't have to be an exotic wood.

The base and top cap could theory rendered and 3D printed. The biggest issue is finding a large enough 3D print. The next issue is cost.

...What do you all think. Is there any merit to this idea? Feel free to pick it apart and give suggestions.

Paul McGowan with PS Audio has a full video showing them assembling the IRS V's and gives a lot of insight to its assembly:

Below are photos of the IDS-25 speakers and the front baffle.
 

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I did a homage to the Infinity RSII and bending the sides using kerf cuts. It was a OB mid so the wider baffle was an advantage for Fp and Fe. Ended up being a good but not a great speaker so was scrapped.

I have heard the Infinity RS1 in the 80s and was blown away with their presentation.
 

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If you mean simply making a wide baffle version of your iDS25 clone, in the shape of the IRS upperbass - HF array modules -sure, why not. I doubt it will bring many advantages per se, but no harm in it. If you mean to add a bunch of extra units on the rear of the speaker as well so you have some bipolar / dipole HF (I can't recall how the IRS V had the rear HF drivers wired off the top of my head) -same deal, although it may make getting the EQ right a bit tricker. Could be an interesting project, if you've the space & funds.
 
Since your room is not that big, you could just build wings to your existing towers.

Will you build the bass lines too?
My goal is to see what it sounds like as an open baffle, so I wouldn't want to build wings to my existing build. Do you think an open baffle version of the TC9 array sound better than in a box?

Regarding subwoofers, I already have 5 subwoofers in a distributed setup and I would also set my current line arrays as subtle bass arrays with the open baffle lines further into the room. I can always dream, but I'm honestly set with bass right now.
 
Building both the curved wings and the base are my biggest hurdles and appreciate any recommendations. I'm not a woodworker.

For the wings, I was thinking kurf cuts and building a form to make the curve with and wood glue between the cuts. Possibly gluing luan to the back for structure and a better look.

I was thinking the base could be made on a 3D printer, but most aren't that large and I was told that it could cost $1000 per.
 
Do you think an open baffle version of the TC9 array sound better than in a box?
OB needs space to breathe, and it does seem, from your pictures, that the room is not that big.
Look at all the pictures featuring that speaker, they place them pretty much 1/3 into the room, and the distance between the speakers and the listener is about the same as the distance between them to the wall behind them.
 
I actually recently moved the current line arrays1/3 of the way into the room. I had watched New Record Day's L.O.T.S. speaker placement video 3 years ago and finally got around to try it ...and my wife was sort of ok with it.

Imaging is significantly improved. Individual instruments can be localized in all their different locations now. There is also and air-i-ness and detail that I didn't have before.

There are a few minor downsides so far: It does sound a little shouty.
Dirac room correction used to make a fig difference and now with such good positioning it seems to actually sound worse.

Surprisingly, the position I ended up in still had enough bass that I was able to eq them down to 20hz. Honestly, it's only going to work like that with primarily vocal music. I'll have to cross it back over too my subs soon as it makes me nervous of clipping.

 

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I agree that OB speakers need room to breath and my room 4.2m x 5.7m was too small to bring the speakers out from the wall.

You just have to make sure your subs can go high enough to compensate for the loss below Fe and the dip from Fp to Fe. Fig 1 shows a 3" driver in OB about 450mm wide. Have a look at the dipole page. https://www.diysubwoofers.org/dipole/

Infinity used a trick on the RSII where they used 2 mids in a 0.5 mid configuration to flatten the FR of the main mid Fp to Fe. Fig 3 shows the effect of this on 3" drivers with the pink being the raw driver without OB losses and the blue the dual 0.5 drivers without OB losses filtered to suit. The summed shows the effect and with OB losses would come down by about 6dB.

The effect of the OB can be seen in Fig 2 with the pink line and the raw driver shown with the blue line (moved up so ignore SPL). Ignore the black summed.

Fig 4 shows the model of a OB 18W8531 speaker where an active woofer compensates for the 18W FP to Fe and below dip. The red is the upper section with a passive filter and the blue is the woofer. The black summed can be altered using the gain and filter in the woofer active stage.

I suggest you build a mock up to see how much you have to fill using the subs or other woofers as the gap would be quite large to Fp on 3" drivers. Good luck with your project.
 

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Is there a wood that's any better suited for doing kerf cuts?

In relation to the project, I'm thinking it may be worth testing this curved open baffle idea with single drivers and foam core board. I also have some inexpensive Aurasound AS3-75-16FR drivers that I'd like to try out with this idea also.