On a side note, do you think room effects/placement had much to do with your experience with these designs? Is had a chance to hear the IDS @ RMAF and thought it could have been setup better but it is hard to do whith such relatively small rooms. Also, I thought yours and one other's room sounded excellent. Both of you had made use of extensive treatment. My friend noticed the same thing and the only thing he knows about audio is whatever I tell him (if he is paying attention). The deifference was very apparent.

Fire away...

Thanks,
Aaron

Of the two designs I thought the McIntosh sounded better. The limitations of the design format in my opinion keep the IDS from being a high end contender. There were some obvious problems with the frequency response and driver breakup modes. The lack of top octave dispersion was also evident and to be expected with a cone driver of that size. I didn't hear anything that would give a good idea of the bass extension but after listening to 100hz on up I really didn't care.

In terms of considering a DIY version of this type of design I would advise against it. EQ cannot fix everything, most importantly off-axis response and driver breakup/ringing. Yes, you could build something that wouldn't be that expensive; however, the tonality and imaging would fall short of a point source using better drivers for a similar budget.

The McIntosh array (not sure of the model # - I think it's a brand new design) sounded better than I had expected. Vertical coverage was smooth and the small drivers / tight driver spacing certainly helped in that regard. I did notice some lack of air in the top octave and missed the extension and detail that I hear with good ribbon drivers. In this case I think the design was executed well but maybe the performance was limited due to the driver choices.

The 2" mid lines and the tweeters they flank are probably sourced from AuraSound. I have a friend who's tested and used the 2" driver and was impressed by it (I also really like their 3" version of the same driver). The problem is that such a small driver will have limited extension and needs to be crossed over fairly high. I don't know where this design crosses over to the dual (10"?) woofers but I found this to be the most obvious flaw in the system. The weight and dynamics of the 80-400hz area are better served with a larger radiating area than what multiple 2" drivers can provide. If they are crossed in the 400-600hz range then you lose the nearfield effect by allowing the dual woofers to cover the area below that.

The driver arrangement for the mids and tweeters did provide fairly smooth horizontal coverage; however, I did still notice some lobing behavior / image shift when moving off the center listening spot. In this regard it was similar to what I would expect from a typical 2-way line with ribbons and 5-7" drivers. I was hoping for maybe a little better performance in this area due to the symmetrical driver layout. Maybe the mid/tweet crossover point and / or slopes were to blame?

Tonally the McIntosh was far better than the IDS. Like the IDS design format still has some limitations but the tradeoffs had less of a negative effect. With some changes I think the symmetrical layout has some promise but the cost could become significant with larger drivers and / or ribbons.