As most of you know, I have had the monumental task of moving our studio\/AV room from Benedict Lake Minnesota, to a new ICF built home in Eagan Minnesota.\n\nThe build thread can be found here.\n\nThe new studio is about 30% larger than the Benedict Studio.\n\nOld room.\n\n\n\n\n\nNew Room.\n\n\n\n\n\nHowever the changes are not just size and cosmetics.\n\nThe total design and infrastructure played a big factor. This house is not a frame house, but a concrete insulated concrete form house, and so the walls are rigid.\n\nBecause polystyrene resonates the outside walls are framed over and filled with sound absorbent material. Great lengths were gone to, to make everything rigid. All walls are rigid and every cavity packed with sound adsorbent material. There is no visible sound adsorbing material or structures. It is all behind the scenes.\n\nSpecial attention was paid to the house grounding layout, and the layout of lighting circuits and dimmers. The equipment chase is the nerve center of Internet, TV and FM distriution. There is a 10" Ethernet patch bay and 2 19" rack mounted Ethernet hubs. All this is ditributed around the house by a network of Tech Tubes. Studio wiring is within metal conduit.\n\nHeat from the power amp rack is achieved via variable speed Radon fan, which is switched with the main left and right power amps.\n\nSo how does this room compare with the last. Well it is a "dryer" room and less warm. The sound is more detialed and imaging better. The bass is smoother and more uniform through out the room. One thing became quicly apparent. My continuously variable baffle step compensation came into play. The front three speakers all needed their BSC signal increased significantly.\n\nThe surrounds are passive, but I have two levels of BSC for them and they were switched to the highest level. The rear backs can be mamaged by adhusting the electronic crossover.\n\nI am firmly convinced that my variable active BSC is a major advance. JBL now do it on their top line speaker. But I can claim to have thought of it first. I think the need to move speakers about to optimize perfrmance is actually about the position that optimizes the fixed BSC of particular speakers more then anything else.\n\nSo the bottom line is that this room has far less effect on the sound presentation than the last. The result is that you get more of the original acoustic, and now it is easy to distinguish the acoustic of venues. This is a new experince. The highly detailed and articulate bass of TL speakers also playing a big part.\n\nSo what is new in the room. The pre\/pro and TV are now 4K. There are two 4K disc players one of which the Sony is truly universal. The old room was 7.1 this one is 11.2.4 Atmos. Powering is from 7 Quad 909 power amps and two Quad 405-2 power amps. The latter for the Jordan Watts ceiling speakers in small sealed enclosures.\n\nI have experimented with using the full pre\/pro crossover. However measurements and listening experince is best with all speakers except the ceiling speakers set to large. The sub ouputs are set to 40 Hz. The previous room set that crossover to 60 Hz. The ceiling speakers are crossed at 120 Hz which is close to their F3 point in the small sealed enclosures.\n\nI have shown detials of the speaker measurments before, so I will mainly concentrate on whole room measurements.\n\nSo here are some of the speaker responses.\n\nFirst the left and right main speakers. Not this is with the midlines powers and BSC sent to the top 10" driver in the midline. The lower driver is not powered hence the bass droop. The amps are tightly packed and I did not want to court trouble trying to switch amps on and off. It shows the good mid band response though.\n\n\n\nI should point out that the HF drop is due to omnimic which rolls off around 15 KHz.\n\nThe center speaker.\n\n\n\nNow the 4" full range vintage JW speakers.\n\nFirst of all the impedance curve and T\/S parameters.\n\nNote that there is a bump at 275 Hz. This is a resonance in the unique suspension system. It is audible and contibutes a slight artificial warmth. \n\nThis is the FR of one of those ceiling speakers.\n\n\n\nYou can see they actually rolling off at 150 Hz. You can see the peak from that suspension resonance. However the midband is very smooth. They do start to roll off at 10 Khz. So it is usual to supplement with a tweeter with first order high pass at 10 KHz. Note there is no break up mode until 15 KHz and that is not great in amplitude.\n\nThis is the sub signal output from the large bass lines.\n\n\n\nSo the four 10" drivers are well supported from 20 Hz to close to 80 Hz, by the pipes.\n\nNow the room measuremnts with all speakers engaged.\n\nThe front row seating.\n\n\n\nThe second row seating.\n\n\n\nThird row.\n\n\n\nYou can see that the second row is the optimal row for listening and indeed it is.\n\nIf you look at the impulse response you can see that Audyssey has done a perfect job of having the sound from all the speakers arrive on time. I should state that Audyssey was only used for levels and distance and not Eq.\n\nThere is no Eq used for any of these measurements. The excellent results acchieved are entirely due to total system design and set up. The room seems to tip up the lower end below 30 Hz, but this is not unatractive!\n\nIn the end it all about creating a believable illusion and that this system does superbly.