Infinity Variants

Unlike many manufacturers, Infinity was continually upgrading and changing their speaker designs during the lifetime of the product. The goal (I suppose) was to incorporate feedback from customers into the latest version of the product. This can sometimes lead to some serious confusion when trying to figure out crossover designs, specifications, etc.

RS-4.5 Variants

In addition to upgrading versions of their products, Infinity would also customize versions of their speakers to individual users. Nowhere was this more evident than in the RS-4.5 line. Despite only producing something like 300 sets of 4.5s, here are various examples of custom or modified RS-4.5s. 
(Photos courtesy of Vito).

RS4.5 Others

Here’s a “standard” pair of RS-4.5s for comparison. Note the EMIMs and EMITs offset to the side, and black acoustic foam on the remainder of the upper baffle. 

Infinity Reference Standard 4.5 Tampa (Large)

Here’s a custom pair. Note the wooden V-notch cut into the black acoustic foam. I’m not sure what that does for the sound, but I sure like the looks of it. 

Infinity 4.5 Center

Here’s another custom set. Note how the EMIMs and EMITs are centered (not offset) in the upper baffle. I have been told that these were custom-designed for
tri-amplification, but I don’t know any other details.


Yet another custom set. Here the EMITs and EMIMs are reversed from their normal position, but still offset (not centered like the pair above).

Infinity RS 4.5 Special Version 6
Infinity RS 4.5 Special Version 3

Here’s a very radical custom set. This looks like a design precursor to the IRS Beta/Gamma/Delta, with the cut-away upper baffle.  Note the horizontal EMIMs, like in the Gamma/Deltas. I’m not sure what that does for the horizontal dispersion, but it does give you a wicked looking speaker.

Infinity_Dual_45_1 Infinity_Dual_45_2

Here’s a very interesting homebuilt set of “dual”4.5s.  The designer took two pairs of 4.5s, put the bass bins on top of each other, and made a separate line source for the EMITs and the EMIMs. Very innovative, though I doubt I would ever have the courage to take a saw to my 4.5s!
(Photo courtesy James Sprunk)

Other Model Variants

Some Infinity owners seem to have a fetish for modifying their speakers, so it is sometimes hard to tell whether a particular variant is a factory modification, or a home-built design. Nevertheless, these are some examples that I found particularly striking, whether factory-made or not.

4.5er Gamma Front 4,5er Gamma hinten
4,5er Gamma Weiche

Here’s another very radical custom set. with the Beta/Gamma/Delta look, with the cut-away upper baffle.  Here they have the EMIMs vertical, so I would think the horizontal dispersion would be much better than the set above..


Here’s a Beta/Gamma/Delta center channel speaker.


Here’s a variant set of Kappas


Here’s a Kappa center channel speaker


Here’s a different Kappa center channel speaker

If you have any other non-standard Infinity designs, I’d love to get some pictures! 
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