Paul McGowan writes: I promised a series that included a video of the setup for our new reference system in the PS Listening room – and I will deliver on that promise for those of you interested in following along.
Building a reference level sound room is no small task and, while a fun project, it’s also one with a deadline for us since we use our listening room to make many decisions on products.
I have sold the main components in the listening room – the Maggie 3.6R’s have a new home and will leave next week – I have one gentleman interested in the Martin Logan subs and am looking for a home for the Tympani III bass and midrange panels. Drop me anote if you have any interest in the remaining items.
Needless to say, by next week I will have the room stripped bare, save for the diffusor treatment that I showed in the picture of the sound room yesterday. For those that read the newsletter as an RSS feed or via email, relative to the website it’s published on, here again is the picture of what the sound room looks like now. This will be a historic picture since next week it’s toast.
Note the forest of white DAAD columns in the room and hidden behind the Maggie 3.6R’s and Tympani III bass panels are three RPG diffusor panels to finish the lot off.
I have spent literally hundreds of hours getting the diffusors in the proper place for the room and have decided that during this rebuild I will mark their place and direction (all diffusors have direction) on some sort of grid map I create before removing them from the room.
My intention will be to put them back in their exact place when starting over – but, only after I take a first step – a step I would recommend for anyone.
That step is to start with the new speakers in the room sans any room treatment at all. I write this not because I believe that’s what I will wind up with, but because it will be important for me to get used to the new speakers and how they work in the room on their own. What differences will they have over the Maggies? Both the Maggies and the Infinity IRS are dipole loudspeakers. By that I mean one radiating surface that is open in the rear so the back wave of the speakers is working as hard as the front of the speaker, and one in the front. The sound out of the rear is out of phase with the sound radiating in the front. Same with the Maggie Tympani III bass panels you see in this picture.
The Infinity IRS is also a dipole down to 150 Hz or so, then a sealed box woofer system takes over. Dipoles are two way streets: on the good side they remove the back pressure and acoustic bleed-through, common in sealed box systems, and on the other side they create giant comb filters one has to deal with in the room or the speaker design itself.
So while both are dipole systems, of which I am very fond of, they will both be very different in the room, thus it’s important for anyone setting up a system in the first place to listen to the speakers in the room sans treatment at first – just to get to know the speakers working in the environment.