3db's Great Room (mainfloor townhouse open concept) setup

[3db]

I swapped out the KX-800 deck for a K720 auto reversing deck that I've had in storage. Plays really nice.

 

[3db]

The new sofa and chair are in, waiting on a couple of ottomans to come in to complete the room. Did another sub placement/REW EQ exercise. Measurements to follow later but this what the room looks like now;

 

[3db]

I redid the sub locations and will upload the pic. Basically the orientation of the left and middle sub has changed with the driver facing the closet corner or back to back. I took three full frequency sweeps with the sub distance of the AVR set to 16.5', 25', and 27' . Although none are ideal, which would be the best setting?

 

[William Lemmerhirt]

If I had to pick I’d choose 25(red). Can you hear any difference between them? I’m a little surprised the graphs didn’t change very much. That’s a pretty wide trough and I would think it would be audible considering it’s like 15db deep. What happens with different XO points?

 

[3db]

If I had to pick I’d choose 25(red). Can you hear any difference between them? I’m a little surprised the graphs didn’t change very much. That’s a pretty wide trough and I would think it would be audible considering it’s like 15db deep. What happens with different XO points?

I should have kept all my sub distance runs but there were a few distances where the crossover region wasn't too bad but it gave me to bass humps. This room is such a bitch to dial in. I will revisit on Monday.

 

[panteragstk]

I should have kept all my sub distance runs but there were a few distances where the crossover region wasn't too bad but it gave me to bass humps. This room is such a bitch to dial in. I will revisit on Monday.

Have you tried messing with REW's room simulator? It might help a tiny bit at figuring out where things can go to help some of the nulls. It was pretty spot on in my theater, but I've got a square, sealed room to deal with. Still not ideal, but not that difficult.

 

[3db]

Here's the new layout of the two subs I mentioned earlier.

Have you tried messing with REW's room simulator? It might help a tiny bit at figuring out where things can go to help some of the nulls. It was pretty spot on in my theater, but I've got a square, sealed room to deal with. Still not ideal, but not that difficult.

I should. Might give me better placement options

 

[3db]

Well I gave it another go yesterday running sweep after sweep in 1ft increments from 1' to 16' . Not seeing anything outstanding happening, I jumped to 44' The RX-V1900 has setting all the way out to 80' . Anyway I started running sweeps above that and it got worse looking. I finally settled on something that was a little better than last time.

This room is an acoustic bear which is impossible to tame without excessive room treatments. I'm going to try this again next week.

 

[3db]

I received my 2nd AC Infinity fan, an S8 and installed it into the system today and tried to clean up the wiring.

 

[Eppie]

Cable management is always a chore with that many components but it's better than letting everything pile up on the floor. Back of my AV cabinet looks pretty similar.

 

[3db]

I've been a busy boy these last few days spending 1.5 days on my greatroom system with my PC, REW and mic after having swapped out the PSB 800 towers for a pair of PSB400 bookshelves.

I know you are all going to tell me to pull them away from the back wall but I get a real nasty bass suck out between 115 to 142 Hz at the listener position. It was such a bad response that even the subs couldn't pull up the response. I saw the mid bass suck out and I wonder if the height of the stand had anything to do with it. The tall stands sit at 23" tall while the short stands are 17" tall.

The first graph below shows the difference in response between tall and short stands when the speakers were placed adjacent to the front of the media console. You can see the deep notch centered around 132 Hz on the tall stands verses a much shallower notch at a 115Hz on the shorter stand

The next graph shows the difference in response between tall and short stands when the speakers were placed near the back wall beside the media console. The response while on the tall stands is only 3db less compared to the adjacent placement from the above graph. You can also see a big reduction of the notch on the smaller stands at the back compared to the previous graph.

The last graph shows the difference in response between the adjacent placement and the backwall placement of the speakers on short stands. Now you understand why the bookshelves are pushed towards the backwall.

 

[TLS Guy]

I've been a busy boy these last few days spending 1.5 days on my greatroom system with my PC, REW and mic after having swapped out the PSB 800 towers for a pair of PSB400 bookshelves.
View attachment 64217View attachment 64218

I know you are all going to tell me to pull them away from the back wall but I get a real nasty bass suck out between 115 to 142 Hz at the listener position. It was such a bad response that even the subs couldn't pull up the response. I saw the mid bass suck out and I wonder if the height of the stand had anything to do with it. The tall stands sit at 23" tall while the short stands are 17" tall.

The first graph below shows the difference in response between tall and short stands when the speakers were placed adjacent to the front of the media console. You can see the deep notch centered around 132 Hz on the tall stands verses a much shallower notch at a 115Hz on the shorter stand

View attachment 64221

The next graph shows the difference in response between tall and short stands when the speakers were placed near the back wall beside the media console. The response while on the tall stands is only 3db less compared to the adjacent placement from the above graph. You can also see a big reduction of the notch on the smaller stands at the back compared to the previous graph.

View attachment 64220

The last graph shows the difference in response between the adjacent placement and the backwall placement of the speakers on short stands. Now you understand why the bookshelves are pushed towards the backwall.

View attachment 64219

Those speakers seem problematic. I note they are discontinued and not currently available. I see there were some quality issues with the spiders of those mid/woofers.

It seems to me that the BSC is actually suboptimal. I am not sure what that suck out is, but it looks like some sort of phase cancellation, may be from a reflection from the back of the cabinet, or a problem in the cone itself. BSC also appears to be marginal to put it kindly. This is probably to up sensitivity. There is also a slight BBC smiley in the mid response. Some people find that attractive.

The bass tuning looks odd. There seems to be some sort of tuning peak at 70 Hz. This may be an attempt to mask the suck out. Then the roll off somehow transitions to 6th order at least at 30 Hz. That is a very strange looking bass tuning alignment. I have a feeling I would not fall in love with those speakers to put it mildly.

 

[3db]

Those speakers seem problematic. I note they are discontinued and not currently available. I see there were some quality issues with the spiders of those mid/woofers.

It seems to me that the BSC is actually suboptimal. I am not sure what that suck out is, but it looks like some sort of phase cancellation, may be from a reflection from the back of the cabinet, or a problem in the cone itself. BSC also appears to be marginal to put it kindly. This is probably to up sensitivity. There is also a slight BBC smiley in the mid response. Some people find that attractive.

The bass tuning looks odd. There seems to be some sort of tuning peak at 70 Hz. This may be an attempt to mask the suck out. Then the roll off somehow transitions to 6th order at least at 30 Hz. That is a very strange looking bass tuning alignment. I have a feeling I would not fall in love with those speakers to put it mildly.

These are old speakers bought used. PSB did have spider detachment issues with this series.
However, you are looking at the speakers interaction with the room which from an acoustics point of view, is a nightmare. To accurately assess these speakers, you need to remove the affects of the room like in anechoic chamber or Klippel.

 

[3db]

After I got the speaker locations dialed in, I went to work on the subs. I left the sub locations alone but used the miniDSP2x4HD to introduce delays on sub 1 for a better response pre REQ EQ.

The first graph shows the individual responses of subs 1 thru 3 and the combined response of all three subs (green trace) before I EQ them with REW.

The next graph shows the difference in response between the combined sub responses and the combined sub responses but adding a 5ms delay on sub1 using the MiniDSP

The last graph shows the difference between Pre REW EQ and Post REW EQ

I may redo this again and play around with the delays on the individual subs to see if I can remove that notch around 120 Hz.

 

[TLS Guy]

These are old speakers bought used. PSB did have spider detachment issues with this series.
However, you are looking at the speakers interaction with the room which from an acoustics point of view, is a nightmare. To accurately assess these speakers, you need to remove the affects of the room like in anechoic chamber or Klippel.

I see issues there, that I really doubt are due to the room. For instance moving the speakers close to the wall likely caused some reinforcement to ameliorate that notch. I would like to see a one meter response of those speakers.

 

[3db]

Its a been a rainy day today so I took another cut into integrating the 3 subs into my main system. Much much better results this time. I took my time and was bound and determined to get it right. Data and graphs will come later tonight or tomorrow. I'm tired from this effort and I still have to make Minnie a new batch of Hamburger Helper plus take her out for a walk.

It turns out that moving sub2 was key to get the response I was looking for. It also allowed me to pull the speakers back away from the wall without getting that bass suck out that I had previously. I still have to use the shorter stands as the response with the taller stands was still bad.

The measurement mess

Sub 2 which was located beside the right speaker has been moved to the left corner of the sofa firing towards the system.

Now looks like this;

 

[3db]

Here are the measurements.

The first graph shows the difference in response of sub 2 only from the old and new locations.

You may think its not much of a trade off or even worse but look at the combined response shown in the next graph. It shows the sub response before and after REW EQ has been applied.

The graph below shows the response for my movie configuration between PEQ=Through vs PEQ=Flat

The graph below shows the response for my music listening configuration between PEQ=Through vs PEQ=Flat vs Pure Direct (no PEQ)

 

[panteragstk]

That green trace of your EQ'd subs looks nice.

 

[3db]

Now that my last dog has passed away 3 weeks ago, I removed the dog bed from the great room and have swapped out a pair of PSB400 for a pair of PSB500. I also spent the day moving that one sub aroud and playing with delays in REW to get that 3rd sub integrated with the PSB 500s. Here's what the room looks like now.

I will post REW plots later.

 

[Danzilla31]

Now that my last dog has passed away 3 weeks ago, I removed the dog bed from the great room and have swapped out a pair of PSB400 for a pair of PSB500. I also spent the day moving that one sub aroud and playing with delays in REW to get that 3rd sub integrated with the PSB 500s. Here's what the room looks like now.

View attachment 65907View attachment 65908View attachment 65909View attachment 65910View attachment 65911


I will post REW plots later.

I'm very sorry to hear about your dog passing