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Discussion Starter #1
I got the PAA3 today and have enough 2" 703/Guildford material to make 384 sq ft of treatment and 32 sq ft of rock wool/Guilford. What decay time would I be striving for in a 14x27x 8' (average) room? Use is movies and personal music time. System is Denon AVR4306 for HT; 2 channel is McIntosh C28/MC2125/Pro_Ject RM-5SE turntable. Klipsch Chorus II/Academy/Quartet and RS-7s for the HT and share the Chorus as the mains. Sub is SVS PB-12/Plus2. After breaking my brain for a couple of years reading up, I not thinking straight now.
 

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You're probably looking around 0.28 to 0.30 in the midband from say 200hz to about 4kHz. Allowable bottom end can be as high as 0.50. The room is very long for it's width and height.

We can tweak these parameters depending on your desire to lean one way or another (2 channel or HT) as they're different design goals. The numbers in the midband above are on the high side for HT and on the low side for 2 channel.

Bryan
 

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Discussion Starter #3 (Edited)
Thanks Bryan,

I turned on the PAA this weekend and started getting familiar with the controls. With 2 of the 2x4 panels located behind my front mains, I had a reading of .45-.50 second at 1kz muted from 85 db stereo mode from Denon AVR. That is assuming I can read instructions correctly. I hope to get a few raw readings (no panels in room but furnished per the norm) this weekend. I would have to say I'd like to lean towards the 2 channel tune while actually the HT gets the most use. Unless I'm wrong, the HT mode would be more forgiving and if that's true I'd like to start with the stereo. For RT60 decay in stereo no problem, bring up to reference level and mute. For RT60 calculation in HT mode would I bring up the pink noise track and put the Denon in 7 channel stereo to get a read on all speakers simultaneously or (groan) test each speaker.
 

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Make sure you start with furinture also in the room. Also, you have to be in the same place in the room for successive readings. Mic obviously is at the seated head position.

For ease, use Room EQ Wizard. It will let us see general trends over time and frequency simultaneously.

Realistically, one can fairly easily calculate the effect of different materials in the room based on their coefficients and square footage. Add that to the stock room factors (drywall walls, furnishings, people, etc. whic all have known acoustical properties) and you can pretty well simulate what you need.

Bryan
 

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Discussion Starter #5 (Edited)
For ease, use Room EQ Wizard. It will let us see general trends over time and frequency simultaneously.

Realistically, one can fairly easily calculate the effect of different materials in the room based on their coefficients and square footage. Add that to the stock room factors (drywall walls, furnishings, people, etc. whic all have known acoustical properties) and you can pretty well simulate what you need.

Bryan
What more do I need and I'll get it. I have a copy of Room EQ, think I still need a mic.
Equipment at my disposal:
RS SPL meter old analog, gotta refresh myself on model
SMS-1 (with supplied mic)
Phonics PAA3
Laptop (slow) or desk top 20' away from sweetspot (long USB reach)
All connections currently are unbalanced RCA (need to get a transformer for the PAA to match preamp)
 
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