Infinity RS 2.5 speaker placement


Hello all,

I've been trying to find the perfect spot for these old behemoths. I have tried the Cardas website, but the formula doesn't seem to work perfectly for these, maybe because they are a mix of cone woofers and the mylar? mids and tweets. He suggest toe in for all speakers while the infinity set up manual says to keep them parallel. Room is approximately 11'x20'x8' rectangle. Big window in front that has been covered and also some crochet blankets on the walls to try and soften things up a bit. I'm looking for the best imaging and soundstage I can get out of these. Any help is greatly appreciated. Btw, it's not bad by any means, just trying to find the best way to set up these speakers.
sswanny_1
I had a pair of 2.5's for quite a few years. I replaced their vintge tweeter & midrange capacitors with modern polypropleans.
They image better when not too far from rear wall due to rear tweeter; I had mine 41" (wall to front).
Lower bass was great, but upper bass was weak due to crossover design (an equalizer would benifit here).

Don't set them too far apart either.
Wings,

Did you notice a difference when recapping them? Probably not a cheap overhaul either, I imagine. I have the optional eq/crossover that came with these, but I have always left it out because the sound seemed to degrade slightly. Also, I have an audio rack against the wall that I'm sure is not helping things, but it's what I have for now.
I should say...on a good recording, the speakers are invisible as is, the stage goes from past the extreme left of the speaker to past the extreme right of the other speaker. The bass is tight and a huge improvement over where I had them positioned to start with which was about 2 ft. from the back wall and 1.5 ft. from the sides. At that position, the bass was so boomy, my tube phono preamp was picking it up at high volume. Part of the problem is that I'm experimenting with my listening position at the same time as speaker position.

In regards to upper bass, I noticed a big change when I got the Bryston preamp, and another large change going from an Adcom gfa-5500 to the edge nl-10. Something like James Taylor's Fire and Rain, the drum fills are right there like a trap set in front of you. I know these old monsters are far from the end all in speakers, especially these days, but for the price used, I haven't heard anything that compares.

In previous experiments with toe-in, I found that it narrowed the effective listening width in my situation, but that was in a different room too, so I will give it a shot just to see...
I had a pair of these and was also puzzled over room placement.

The owners manual gave little guidance. You can get one at the Infinity Owners group's library at Yahoo. Might be worth joining.

They are a complicated design. The 2 EMIT tweeters on each speaker are out of phase and pointing front and back or dipolar.

The single EMIM mid-range is open to the back, so they are bipolar.

And while the 15 woofer looks conventional, except for the clearish poly cone,, it has 2 windings and the cross over is designed to have a different resonances for each.

The woofers are not very efficient, so there are resistors in the mid and tweeter circuit to waste power and equalize response. And several switches to set levels.

I think that the low efficiency of the woofers encouraged owners to turn their amps up until they clipped, there by frying the EMIT and EMIM units. The speakers are set up for biamping and I would recommend it to isolate the woofers and possible clipping.

Be real careful handling the upper covers, the frames are really easy to break.

As to room placement, it didn't seem to matter as much as some other designs, but I liked them 3-4 feet from the back and side walls.

(It has been a couple of years since I had them, so some of my details might be a little off.)
They are actually Watkins Engineering 12" dual drive woofers. It is a dual voice coil woofer with one 4-ohm coil and one 2-ohm coil which play at different frequencies. I replaced the originals with exact replacements from Watkins Engineering themselves. I have never come close to clipping the edge, as it will deliver 900 watts continuous into 2 ohms and I have no idea about the transient power ability but I'm not interested in biamping. The system is already more than loud enough. Besides, $15k for another comparable amp is way outta my budget.

Both sets of upper grills were pretty much hammered when I bought the speakers, so a rebuild project is in order sometime in the future.

Also there are two emits and two emims per speaker plus the one twelve.

And I do have a copy of the owner's manual, but thank you.
I own RSIIb's as my main speakers. They have more drivers than the 2.5's so take this with a grain of salt, but I find that a slight toe-in works best - I cross the tweeters a couple feet behind my listening position.

If you intend to keep them you should look into the new EMIM diaphragms offered by Apogee Acoustics in Australia - I have them and they sound incredible, like an electrostatic with 10X the dynamic range.