help buying irs beta


Hi ima newbie just trying to break into the real hifi world.i have the opportunity to get the irs beta for a steal.i need some advice on what problems to look for and also wondering if the sunfire 400wpc 7channel amp would be okay for these speakers using 4 of the channels 2 for the upper panel 2 for the woofer towers
leximarley4242
I formerly owned the similar RS-1b, and unless you’re a masochist I would instead get a pair of Eminent Technology LFT-8b, which employs similar but superior drivers to the EMIM and EMIT in the Infinitys.
The later High Energy Emit and Emim drivers used in the Infinity IRS speakers such as the IRS Sigma and Epsilon were quite a bit better than the previous generation, as were the IMG bass drivers vs the old polypro bass drivers. Even the Infinity Renaissance 90’s were better sounding in many respects than the old RS-1b. I can’t speak for the Eminent Technology speakers, though I note from the TAS review they are very insensitive and not completely coherent.
The ET's are rather insensitive (but not as much so as the other magnetic-planar, Magneplanars), but coherency is one of it's strong points; a single driver covering 180Hz to 10kHz! The incoherence Robert Greene talked about in his TAS review was between the ET's m-p midrange driver and it's dynamic woofer. He found switching the polarity of the woofer eliminated that lack of coherency between the two, making for an extremely coherent speaker. The woofers polarity is easily switchable by the owner, the driver leads being on the outside of the bass enclosure.
The ET speakers might be a good value option, though I would take a pair of mint Infinity IRS Omega's over the ET's 5 times out of 5, but then again I am an Infinity lover. The IRS Omegas were the last Infinity IRS speakers released in Infinity's heyday in 1998 & were heavily upgraded with new Auricaps, coils, DH Labs cables etc, but are very rare in the US as they were only sold in Europe and Japan.
There are a couple of pairs available on this site, you use to be able to buy Irs betas a few years ago for under 6k, times have changed, I would check for the same things as mentioned by other members, I have IRS epsilons and also had in the past IRS sigmas, renaissance 80’s and renaissance 90’s so I know the sound of the newer infinity emit’s and emim’s, I auditioned a pair of IRS betas a few years ago and thought they sounded awesome, they had a big 3d sound stage, great imaging and the best bass I ever heard, I had to lower the bass level down to the 10 O’clock position or less for it to sound balanced with the high frequency drivers, in comparing the IRS epsilon to the IRS betas, obviously the betas had way more bass output but the bass was not as quick as compared to the epsilons bass, I believe this had something to do with the epsilons improved SCU box , the sound stage was deeper and slightly wider on the betas being that they are dipole and because of the semit, that said the newer style planar drivers used in all the above mentioned infinity speakers have way less coloration than the older style planar drivers used in the betas, to me the betas planar drivers have a ringing sound to them compared to the newer planar drivers used in the infinity renaissance 80, renaissance 90, IRS omega, IRS sigma and the IRS epsilon, If you didn’t have one of the newer infinity speakers to compare to you probably might not notice the ringing sound, that said if you have a big enough room for the batas I say go for it, I have my epsilons in a 19x15 room and it’s still too small for them.