Gene and Matt recently posted an extended interview with Arnaud Laborie, founder of Trinnov labs in France, on the Audioholics website.\n\n\n\nThis I think is certainly the best discussion I have ever heard on room acoustics and their modification. In fact it was one of the most interesting and thought provoking presentation on an audio topic I have yet encountered. Gene, I really appreciate you arranging this. This is the sort of presentation that separates and distinguishes this site from the rest, and makes me proud to be associated with it.\n\nAs I think many of you realize I have been very much a sceptic of current and past theories, on the nature and correction of these problems. Now I have an eminent ally, with the knowledge and scholarship to start to place a more revealing light, and possible solutions to this complex problem.\n\nAs I suspected, a lot of evidence was presented concerning current errors in our thinking and the harmful effects of many current nostrums. A lot of this was in line with what I have observed over the years, and the reasons my set ups, especially my HT room differs from much recommended current practice. So to an extent, I can say "I told you so."\n\nThe importance of accurate speakers especially as regards dispersion, I think is now accepted. The futility of Eq, for not only speakers, but room effects was discussed. Simply the issue is, while you may improve some aspects, you will make others a lot worse. My experience and measurements have long convinced me of this. As you know I don't use Audyssey, and this reinforces my impression that approaches of that type are on the whole worse than useless.\n\nThere was one piece of interesting discussion about wet and dry listening rooms. As I have maintained a listening with a lot of reverb "wet" is not necessarily a bad thing.\nOur family room in our former lake home had a pronounced echo, very wet. Yet the sound of that room was excellent, in fact stunning with my three way speakers. Quite a number of visitors commented on it. The trick is having good speakers in terms of axis and off axis response.\n\nThe meat of the discussion was how to optimize room reverb, in terms of LF response and mid low and mid response. So the research is focusing on using subs, two or three, at each end of the room, to not only reproduce bass, but neutralize each others reflections. Apparently there is advantage to having lower and higher subs, but this all gets complicated and costly.\n\nGene made the remark that running speakers full range and adding the sub could have advantage. Well that is what I have done. I get better measurements, and it sounds definitely better with LFE plus main, in my room. All my seven bed speakers are run full range, and that includes the shorter line of the left and right mains. It helps that I can carefully set the output below the transition frequency to speaker and position of the mains, center and rear backs. The surrounds have a choice of two settings. Only my four ceiling speakers are fully crossed over. So the shorter lines have an F3 of 42 Hz, 12 db. roll off, the center 48 Hz, 12 db. roll off. The surrounds 52 Hz, 12 db. roll off. The rear backs 27 Hz 12 db. roll off. So there is significant bass from all seven bed layer speakers, and they are quite robust enough to tolerate high spl.\n\nI had never understood why this rig sounded so much better with LFE + main rather then crossed over. But it definitely does, and this presentation gave me insights as to why. I think it is helped by the fact that all the speakers measure well in proximity and at every seat in the room.\n\nThe other part of the presentation was devoted to higher frequency reflections, which are dealt with passively rather then actively. In other words JUDICIOUS use of sounding adsorbing material. Of particular concern is the back wall. This is not new news, and one of the features built into my room, to dampen and break up reflections and do it in a useful way.\n\n\n\nThe architecture of the side walls also mitigates against dominant reflections.\n\nSo towards the end there was an interesting discussion on how to handle the transition from the LF active DSP to the higher frequency passive. As this is a crossover in effect that has to be handled. This it seems is still a work in progress.\n\nIn conclusion I commend this video presentation to all members, and be prepared to have more than a few sacred cows debunked.\n\nOne once again many thanks to Gene, Matt and especially Arnoud. Did I say this is a must see video?