Infinity IRS Sigma for 2K...Should I do it??

Hi all,

I have an opporunity to buy a pair of Infinity IRS Sigmas for $2,000. As you probably know, these list for $10K. I'm somewhat familiar with the Infinity IRS series, but that's about it.

Do these require a lot of power?? Could I find anything comparable for that amount of money?

This seems like s steal, but I need your advice.

Hello Danheather:

The IRS Epsilon, Sigma, Delta were the last real High-end speakers Infinity made. The newer stuff is good, but lacking the planar implementations. I own IRS Beta, and love them, so I may be a bit biased, however I also have another system with Aerial 10t's. Love 'em both, but they are two different means to the same end.

One concern is replacement parts, if you purchase the Sigma, parts are still available from Infinity which is a good thing. I feel that you should go for it, I've heard both the Epsilon and the Sigma, and liked them both. You do not say where you are located, as there is a pair of Epsilons listed here for $2600, needing local pickup in Arizona. If you were close to those, it would be an even better deal IMHO, with the advantages of the Epsilon's use of the servo feedback woofer as well as the LEMIM planar midrange driver. The drawback here is the Epsilons require bi-amping, where the Sigma's do not. Best of luck to you regardless of your final decision, please post and let us know what you do buy, and your thoughts.

Thanks Beemer. I saw Epsilons too. I'm in California. My only major concern is with regard to power. They're going to be in a relatively small room so I don't think they'd need a TON of power, but what would you say is the minimum requirement??

Thanks again,

The Sigma tech sheet I have states 87db at 1 watt/meter.
Not the highest in efficiency. A good amp 150w/channel+ with high current reserves would probably be best. Plinius comes to mind as a good choice, as would be Classe. If these were a tad more efficient, I'd tell ya to try the Gamut D-200, which, IMHO is a really great sounding amp, however it is current limited. On my 10t's there was a problem with woofer control, although the midrange from the Gamut was spectacular!

Regardless of how good the speakers are ( and i'm sure that they are quite good ), you REALLY do need to consider their size if going into a smaller room. Larger speakers require more room to breath and focus. While they might be a great deal that you don't want to pass up, the bottom line is would the give you what you want in the room that you have to work with ? Even the best deal is no good if you aren't happy with the purchase in the long run. Sean
The Sigmas do need some room to do there thing properly as they do not sound that great at low volumes - they need a very good amp as suggested above - the Innersound and Electrocompaniet are also good high current choices. They are really good speakers and at 2k I would probably talk myself into givivg them a shot because you could easily get all of your money back or even more if they do not work out.
I was part of Sigma's design team and can tell you catagorically that Sigma is a fine speaker; however, it is influenced greatly by the power amp., other electronics and connecting wire. Sigma is slightly bass heavy in a small room, therefore, room size is of consequence. The speaker must be kept on tiptoes to keep it raised off the floor for cleaner, more articulate bass response. The system should be biwired for optimum results. Separate power amps will produce even better sound but the amp on the bass end must have high current capability. Sigma's impedance, as I remember, is quite low and will turn off mediocre power amps with flimsy power supplies and heavy limiting in the output stage. If you require additional input, let me know.
I looked up the Sigma's manufactured cost and it came to a little above $4,000 a pair packed and ready for shipment. It may surprise you, however, that the Sigma was not designed for the U.S. market. It was ordered by Infinity's office in Denmark who had orders for over fifty of these fine speakers, plus an order for twenty-five for Japan and the rest of Asia. The original wood was Sandos but it turned out that this type of wood (like Rosewood)was scarce, so we went to a walnut color. It looked fine.
If the person who owned the pair of Sigmas that you are considering buying didn't abuse them, then the 2k price is a good one.

How did sigma wind up in the U.S. market? I suppose that marketing had a few dozen pair remaining and sold them to various U.S. dealers at special prices? I really don't know specifically how people in the U.S. obtained Sigmas but the dark walnut turned up in various places.

Since the woofer is fairly close to the floor, the speaker should be raised off the floor as much as possible (without affecting its stability) to prevent it from using the floor as a bass enhancer. Bass resonse on the Sigma has a gentle rising characteristic in free space and the floor merely adds to the rise if it is too close. The spikes that come with the speaker are mandatory.

Leon, thanks for all of the background info on these speakers. Out of curiosity, do you remember what woofers were used in these speakers ? I know that Infinity had used some Watkins "dual drive" woofers in some of their models of the same time frame. Is that what made it into the Sigma's also ? Sean
My apologies for never following up on this. I've decided not to purchase the speaker for three reasons. 1) They simply will be too big for my room. 2) I don't have enough power to drive them properly. 3) I've fallen head-over-heals for another speaker. I'm eagerly awaiting the arrival of my Magnepan 1.6/QRs.

Thanks to everyone for your posts and my apologies once again for not keeping on top of this. Poor etiquette on my part.

Happy listening.
These speakers were on sale in the Netherlands and Germany for about $2000 brand new. They were not quite my taste, also because I preferred the Omega's at only $1500 brand new. Didn't buy either, just not the sound I was after.