Official JBL Synthesis / Pro / Revel Home Theater Thread - Page 111 - AVS Forum | Home Theater Discussions And Reviews
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post #3301 of 3652 Old 03-07-2019, 09:05 PM
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Originally Posted by DS-21 View Post
He’s here so he can correct if needed, but IIRC Harman first hired Dr. Toole to replace Andrew Jones as the chief engineer for Infinity speakers after Mr. Jones left for TAD and Pioneer.
Whoa, whoa, stop the rambling opinions! There are some strange rumors floating around this forum and they are off track.

I was hired as the Harman International Corporate Vice President of Engineering in 1991. I was a Harman corporate officer.

Shortly after joining I set up and managed the Corporate Research Group as an additional activity. I was originally hired to bring the science I had generated in Canada at the National Research Council to the Harman group of brands - all of them. I was responsible for the construction of excellent new 4 pi and 2 pi anechoic chambers and modern digital measurement systems (which I had been using since 1983 at the NRCC). There were understandable stresses as familiar old measurement methods, and golden ear subjective evaluation techniques were challenged.

I designed no loudspeakers, only provided guidelines. Those engineers, worked for the brands: JBL, Infinity, Harman Kardon, and Revel in the Consumer Group and the separate operation: JBL Pro. Greg Timbers has been mentioned. He was the most senior consumer group engineer, but not the engineering manager. A few years after I joined Harman, the Infinity brand, which had been purchased, was leaderless, and Laurie Fincham, recently departed from KEF in England, was hired. He wanted some of his old KEF engineers, particularly Andrew Jones. I arranged the paperwork for Andrew to be able to join Infinity in Northridge California.

Unfortunately the relationship did not work out, and Laurie Fincham moved on to THX, where he remains. Shortly afterwards Andrew Jones moved on to forge his own illustrious career. Both are talented people, and friends.

So, those are the basic facts . . .
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post #3302 of 3652 Old 03-07-2019, 09:09 PM
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Quote:
Originally Posted by Floyd Toole View Post
Whoa, whoa, stop the rambling opinions! There are some strange rumors floating around this forum and they are off track.



I was hired as the Harman International Corporate Vice President of Engineering in 1991. I was a Harman corporate officer.



Shortly after joining I set up and managed the Corporate Research Group as an additional activity. I was originally hired to bring the science I had generated in Canada at the National Research Council to the Harman group of brands - all of them. I was responsible for the construction of excellent new 4 pi and 2 pi anechoic chambers and modern digital measurement systems (which I had been using since 1983 at the NRCC). There were understandable stresses as familiar old measurement methods, and golden ear subjective evaluation techniques were challenged.



I designed no loudspeakers, only provided guidelines. Those engineers, worked for the brands: JBL, Infinity, Harman Kardon, and Revel in the Consumer Group and the separate operation: JBL Pro. Greg Timbers has been mentioned. He was the most senior consumer group engineer, but not the engineering manager. A few years after I joined Harman, the Infinity brand, which had been purchased, was leaderless, and Laurie Fincham, recently departed from KEF in England, was hired. He wanted some of his old KEF engineers, particularly Andrew Jones. I arranged the paperwork for Andrew to be able to join Infinity in Northridge California.



Unfortunately the relationship did not work out, and Laurie Fincham moved on to THX, where he remains. Shortly afterwards Andrew Jones moved on to forge his own illustrious career. Both are talented people, and friends.



So, those are the basic facts . . .


Thanks for the correction, Dr Toole. False info deleted.
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post #3303 of 3652 Old 03-08-2019, 07:36 AM
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So many JBL threads, hard to tell where to post. Will be setting up LSR308P’s for L/R today, coming from HSU HB1 and HC1 center.

Posting here because haven’t decided what to do for center channel yet

LSR 308 horizontal? Not sure if I can accommodate the height, even on its side at 11”

So also saw the SAM3HA https://www.jblsynthesis.com/productdetail/sam3ha.html

The spin on it looks pretty good.

Studio 235C https://www.jbl.com/loudspeakers/STU...SAAEgLwGPD_BwE


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post #3304 of 3652 Old 03-08-2019, 07:51 AM
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Any reason you did not get the MKII version of the LSR308P?

You could consider the LSR306P MKII for slightly smaller speaker dimensions. It would be good if you could stay with similar speakers and keep them vertically oriented.

You could go with either the 305 or 306 horizontal if necessary. At least they would be of the same family. Crossing over at 80Hz with a pair of subs would help the smaller center channel and the 308's as well.
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post #3305 of 3652 Old 03-08-2019, 08:26 AM
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Official JBL Synthesis / Pro / Revel Home Theater Thread

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Originally Posted by Rex Anderson View Post
Any reason you did not get the MKII version of the LSR308P?

You could consider the LSR306P MKII for slightly smaller speaker dimensions. It would be good if you could stay with similar speakers and keep them vertically oriented.

You could go with either the 305 or 306 horizontal if necessary. At least they would be of the same family. Crossing over at 80Hz with a pair of subs would help the smaller center channel and the 308's as well.


Yes, I did get the MK2,s. If it will fit, do you think a horizontal 308 would be better than one of the above MTM centers? I currently cross at 110 as I have very high quality, efficient subs. Not opposed to lowering to 80 Hz with the 308’s


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post #3306 of 3652 Old 03-08-2019, 09:14 AM
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Originally Posted by bear123 View Post
Yes, I did get the MK2,s. If it will fit, do you think a horizontal 308 would be better than one of the above MTM centers? I currently cross at 110 as I have very high quality, efficient subs. Not opposed to lowering to 80 Hz with the 308’s. Sent from my iPhone using Tapatalk

Are you aware the SAM3HA is $2,500? Studio235C has dual rear ports, probably not a good choice if your center channel is close to the wall. I'll look into more options. Powered horizontal center channel to match the LSR3 series is a challenge.
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post #3307 of 3652 Old 03-08-2019, 11:20 AM
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Official JBL Synthesis / Pro / Revel Home Theater Thread

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Originally Posted by Rex Anderson View Post
Are you aware the SAM3HA is $2,500? Studio235C has dual rear ports, probably not a good choice if your center channel is close to the wall. I'll look into more options. Powered horizontal center channel to match the LSR3 series is a challenge.


Wow . Now I’m aware. Was just browsing around a little at work. Ok. That one is out of question for sure. I’ll see if the 308 will fit on its side but I think it will block some of my screen which is already VERY high. I kind of hate to use a LESS capable speaker for the center. Center is close to wall but, if I cross a little higher, say 100-110, I wonder if this would reduce issues of the port being close to the wall.

Center does not have to be powered. I have Denon x3300.

I haven’t seen it done for the 3 series, so in case anyone is interested, I’m going to try to do compression sweeps with the 308’s


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If you don't need a powered center speaker, you could consider Revel C25. What about using all passive Revel Concerta 2 series speakers? M16's are very nice speakers and you have the power to drive them.
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post #3309 of 3652 Old 03-08-2019, 11:55 AM
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I haven’t seen it done for the 3 series, so in case anyone is interested, I’m going to try to do compression sweeps with the 308’s
I can't remember if I posted it before but I did do a compression sweep on a pair of 305s. In 10x12 room, no room correction, about 7 feet distance.
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post #3310 of 3652 Old 03-08-2019, 05:02 PM
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If you don't need a powered center speaker, you could consider Revel C25. What about using all passive Revel Concerta 2 series speakers? M16's are very nice speakers and you have the power to drive them.
If one of my primary goals wasn't to increase my clean output capability over the Hsu's, I think a Revel Concerta 2 setup would fit the bill perfectly for my goals of sound quality, aesthetics, and size. The sealed center probably would be superior for sound quality as well without the rear port. My hope is that the larger 308's will have an output advantage along with the improved sound quality I expect.

I'm not sure if 86dB speakers would meet my output goals.

Any speculation as to whether the 308's will play louder and cleaner than the M16's, or Hsu's HB1 MkII?

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I can't remember if I posted it before but I did do a compression sweep on a pair of 305s. In 10x12 room, no room correction, about 7 feet distance.
They look good up to the next to last sweep pretty much top to bottom..so around the 97ish dB sweep. Impressively flat output down to 40 Hz as well...even up to the top sweep although the last sweep found their limits below 300Hz. Of course, this is with a sine wave sweep, perhaps their burst output for actual content may be a few dB higher.

If so this would put you around 100dB across the range...with some headroom left up top. That looks pretty good for a small bookshelf I see is on sale now for less than 250/pr. You have the original or MKII?
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They look good up to the next to last sweep pretty much top to bottom..so around the 97ish dB sweep. Impressively flat output down to 40 Hz as well...even up to the top sweep although the last sweep found their limits below 300Hz. Of course, this is with a sine wave sweep, perhaps their burst output for actual content may be a few dB higher.

If so this would put you around 100dB across the range...with some headroom left up top. That looks pretty good for a small bookshelf I see is on sale now for less than 250/pr. You have the original or MKII?
Original. It's worth mentioning that at 200hz a cabinet resonance is causing about 30% THD (3rd dominant) at that upper level. That doesn't get down to 10% until the -22.5 setting which is about 85dB.

I dunno if the MK2 addressed this resonance or not.

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post #3313 of 3652 Old 03-09-2019, 05:28 AM
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Original. It's worth mentioning that at 200hz a cabinet resonance is causing about 30% THD (3rd dominant) at that upper level. That doesn't get down to 10% until the -22.5 setting which is about 85dB.

I dunno if the MK2 addressed this resonance or not.
Sounds like, for someone keeping these long term and playing loud, opening the cabs and bracing them wouldn't be a terrible idea. Guess it depends on what part of the cab is resonating...the sides, the metal rear wall, or the plastic baffle. I wish JBL had spent another $10 on cabinet construction to cure this though. I think the main features of the the MKII are upgraded drivers, although the front baffle design is different.
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Ok, 308's are now properly hooked up, gain all the way up on the amps. Low level listening sounds really good with no eq applied...very clear. Household is not awake yet so can't demo now at louder volumes. HAVE to cross to subs, as these have too much bass for my bookshelves to tolerate...They cause a lot of resonance and vibration when full range. So for demo I can only listen at low level for full range. On a positive note, with gain at 100% on amps, my ear has to be within a foot of the tweeters to hear the slightest hiss. Past a foot I hear nothing, so this is good so far. Rummaged through my box of old wires and found a good long dual RCA cable, that I modified into a pair of single cables(just pulled it apart )


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Quote:
Originally Posted by bear123 View Post
Sounds like, for someone keeping these long term and playing loud, opening the cabs and bracing them wouldn't be a terrible idea. Guess it depends on what part of the cab is resonating...the sides, the metal rear wall, or the plastic baffle. I wish JBL had spent another $10 on cabinet construction to cure this though. I think the main features of the the MKII are upgraded drivers, although the front baffle design is different.
One report over at diyaudio said a simple horizontal cross brace inside fixed the issue. At these pricing levels, anything that adds $10 is serious enough to affect sales and profit margins.


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post #3316 of 3652 Old 03-09-2019, 06:38 AM
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As much as I hate to post an unfinished installation with crappy looking wires everywhere, here is at least a sense of that they will look like in my space, and how they compare to my old speakers.




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Quote:
Originally Posted by bear123 View Post
If one of my primary goals wasn't to increase my clean output capability over the Hsu's, I think a Revel Concerta 2 setup would fit the bill perfectly for my goals of sound quality, aesthetics, and size. The sealed center probably would be superior for sound quality as well without the rear port. My hope is that the larger 308's will have an output advantage along with the improved sound quality I expect. I'm not sure if 86dB speakers would meet my output goals. Any speculation as to whether the 308's will play louder and cleaner than the M16's, or Hsu's HB1 MkII?
I think the 308's will play louder than either the Hsu or the Revel M16. I think the C25 would be a good choice for a horizontal center channel that will match the neutral on and off axis response that is the goal of both those JBL and Revel speakers.

What happened to the woofer on that 308?

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post #3318 of 3652 Old 03-09-2019, 07:32 PM
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I think the 308's will play louder than either the Hsu or the Revel M16. I think the C25 would be a good choice for a horizontal center channel that will match the neutral on and off axis response that is the goal of both those JBL and Revel speakers.

What happened to the woofer on that 308?
I think you must be seeing a reflection on the woofer maybe? Its perfect. I'll look for some spins on the C25. I don't think I can use an active center even if I wanted to as I don't think I have a way to run it off my AVR, so the issue of fitting a 308 horizontal is moot.

I didn't get around to compression sweeps today, but I did do some spirited music listening at and above reference level. The 308's sounded really good and seemed to hold up just fine output wise. I don't think I have them calibrated quite perfect as I did not run room correction to set levels, but the gain on the amps are all the way up. So they are as loud as I can get them without Audyssey turning up the output level.....Not even sure how it will work since I'm using my pre-outs for L/R and normal center channel for center. It sounds really good without Audyssey but I am curious to see what my FR looks like, and what Audyssey does to the response. I found Audyssey to be a big improvement on how the Hsu's sounded, and I like Dynamic EQ for the bass for low level listening.

Although I haven't determined the exact SPL capability yet, I can tell you they will go louder than I will ever listen outside of a brief demo for part of a song or movie clip.
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I had upgraded to the JBL 4429's for my LCR back right before Christmas. Had the funds been there, I would have probably looked at the 4367's or even M2's....

Due to several reasons, I really just got them setup and then yesterday they were finally calibrated.

WOW...these are a great speaker! I replaced a trio of 708p's with these.
Kudos to the 708p's because the difference wasn't as great as I maybe thought they would be, which says a lot about the 708's. I also think the active part of the 708's are a nice feature. Makes me wonder how good the M2's sound when they are running with Crown amps.... Not to digress.

Overall the differences are there and I am happy with how everything sounds. I will also say that dialog is probably where I am hearing the biggest difference. A Star is Born and The Greatest Showroom sounded phenomenal....

Anyways. I thought I would share.
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post #3320 of 3652 Old 03-11-2019, 05:51 PM
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JBL 308P MKII Compression sweeps:



Distortion on the sweep just before full bandwidth compression(just below the top sweep):


They played a bit louder than I was expecting them too.

Distance:
Left: 10'9"
Right 11'9"
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Originally Posted by bear123 View Post
JBL 308P MKII Compression sweeps:

Spoiler!


They played a bit louder than I was expecting them too.

Distance:
Left: 10'9"
Right 11'9"
Thanks for the sweeps.

Have some quick questions though...

1. Just to re-confirm, are the compression sweeps for one 308P MkII or two of them playing the sweeps together?

3. If you did the sweeps with only one 308P MkII, how far was it from the listening position? You have two different distances listed in your post.

3. Gooddoc also did some compression sweeps with one 708i from 10 ft away. How come the results look so similar with maybe even yours looking better (unless I am missing something) despite the 708i having much more amp power and a compression tweeter?



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Ah, good points. My sweep was with both L and R speakers going, hence the different distances. Goodocs's was with one, and his sweep level goes higher, so the 708 definitely seems more capable. I'm pretty much all in around 102ish dB before I get full range compression....his 708's seem to be above 105 with a single speaker.

Im also guessing? that if a speaker like the 708 can exceed 105 dB with a sine wave, its burst capability for transients on real world content would be higher, and perhaps lower distortion at 105 db than what the sine wave would produce?

Perhaps I'll run some more sweeps with only one speaker. I suppose my intention was to check the FR at the MLP with both speakers going but didn't really think about it.

Not sure if I will be keeping the 308's.........
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post #3323 of 3652 Old 03-13-2019, 07:42 AM
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Ah, good points. My sweep was with both L and R speakers going, hence the different distances. Goodocs's was with one, and his sweep level goes higher, so the 708 definitely seems more capable. I'm pretty much all in around 102ish dB before I get full range compression....his 708's seem to be above 105 with a single speaker.

Im also guessing? that if a speaker like the 708 can exceed 105 dB with a sine wave, its burst capability for transients on real world content would be higher, and perhaps lower distortion at 105 db than what the sine wave would produce?

Perhaps I'll run some more sweeps with only one speaker. I suppose my intention was to check the FR at the MLP with both speakers going but didn't really think about it.

Not sure if I will be keeping the 308's.........
Sweeping both speakers doesn't really tell you much either. For almost all content outside of two channel stuff, you'd want to sweep and test separately.

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post #3324 of 3652 Old 03-13-2019, 01:12 PM - Thread Starter
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Hello all! Long time, no post Hope everyone is well!

Since so much of the science discussed in this thread is based on the work of Dr. Floyd Toole, it was requested that I post the following article Floyd wrote about how he designed his own personal system here in this thread. This way more people can read it, quote from it and comment. There is much to learn here! It's also a great opportunity to share Dr. Toole's awards and credentials, so people can see he's not just a guy with an opinion . Here goes, along with the introduction I wrote included in italics:

So, if you are literally one of the world's foremost authorities on loudspeakers, rooms, and acoustics - and have literally written the industry accepted book on the subject -- what components and speakers do you chose for your own personal home theater and listening room? And how do you address the acoustical requirements and challenges of what is very much a "real world" (vs. custom designed) listening space?

That's the question I recently had some first hand experience getting answers to, as I had the unique honor and privilege of providing some projection system advice and guidance for Dr. Floyd Toole's recent home theater "makeover." For anyone not familiar, Dr. Toole is as close as one can get to a celebrity or legend in sound reproduction circles, and for good reason. Dr. Toole was the one to spearhead the first scientifically-controlled study of sound / acoustics at the National Research Council in Canada, starting back in the 1970s - research that continues to this day at Harman labs, which is still the largest and best-equipped acoustics R&D facility in the world. Though Dr. Toole is now partially retired, his research program continues at Harman under the guidance of Floyd's colleague and protege, Dr. Sean Olive. And the results of this research are published and peer reviewed by the entire audio industry in the true spirit of science.

It cannot be overstated how much the work of Dr. Floyd Toole has advanced the legitimate state-of-the-art in accurate sound reproduction. Dr. Toole has published numerous papers in the journals of the Audio Engineering Society and the Acoustical Society of America, as well as the aforementioned "industry textbook" on acoustics, loudspeakers and rooms. A measurement technique based on his research in the 1980s and further developed in the Harman research group is now a core component in ANSI/CTA-2034-A (2015). “Standard Method of Measurement for In-Home Loudspeakers”, Consumer Technology Association, Technology and Standards Dept., www.CTA.tech. For his scientific contributions to the audio industry he has been recognized with:

· Two Audio Engineering Society (AES) Publications awards (1988, 1990)
· The AES Silver Medal award (1996) and the Gold Medal award (2013).
· CEDIA Lifetime Achievement award (2008)
· Beryllium Driver Lifetime Achievement award from ALMA (Association of Loudspeaker Manufacturing & Acoustics International) (2011)
· Inducted into the Consumer Technology Association Hall of Fame (2015)
· The Peter Barnett Award from the Institute of Acoustics (UK) (2017)

He is a Life Fellow and Past President of the AES, a Fellow of the Acoustical Society of America and a Fellow of CEDIA (Custom Electronic Design and Installation Association).


In addition to all of that, Floyd is a man with means and impeccable taste. This is all reflected in his component selection as well as the overall aesthetic of the room (all well documented below). In creating this system, Floyd did not spare expense, nor did he waste money on "snake oil" components that often clutter up so many other supposed "state-of-the-art" or "reference" systems. As a result, the system described below can very well be described as "scientifically justified high end" -- which also sums up the approach we have when it comes to designing audio and video systems. I am proud to say that a great many of the same exact components and speakers are being utilized in our Reference Showroom (which also happily doubles as my own personal home theater ).

It is with tremendous honor I share with you the following article, courtesy of Dr. Floyd Toole himself. It was a true privilege to spend four solid days at Floyd's home, getting to know him and his lovely wife Noreen. The fact that I played even a small part in helping enhance the performance of Floyd's system makes this an even more unique and treasured memory.

Floyd, take it away!


The Toole’s Entertainment Room: 2019
By Dr. Floyd Toole

A room for lovers of good sound and loudspeakers


Those who have read my new book will have learned that much of what has motivated my research over my 50 year career has been the challenge of delivering good sound in rooms - any room. Dedicated listening spaces like recording control rooms, custom home theaters and stereo installations are able to employ acoustical treatments and methods that are not friendly to décor in typical domestic rooms. In those spaces it is routine to compromise visual aesthetics for real or imagined acoustical benefits. The decision of whether to create a dedicated custom room or to adapt an existing room is a choice driven by one’s chosen lifestyle, family needs, available space and, of course, budget.

In my case, it was lifestyle. We had no need for a dedicated “escape”room, but instead wanted a multipurpose room that was relatively normal in appearance, usable for reading, conversation, casual TV viewing, background or foreground music, and, with room darkening shades, suitable for engaging big-screen movie experiences at any time of day. Ekornes Stressless seating fits human bodies and is easily moved into arrangements suiting different needs at different times. Small movable tables replace cupholders, which are not optimum for our preferred beverage: wine. Four subwoofers in a Sound Field Managed configuration eliminate the need for massive bass traps, which is a major advantage.

The following is a panoramic photo of the room (geometric distortion included) showing seating in the conversational mode. The equipment racks are on the right, under the projector opening - in what was a fireplace space in the original house.



The room was configured in 2000, as a 7.1 system. The front wall was deliberately constructed as a low-mid frequency sound scattering surface using display niches and other depth variations (including spaces behind the fabric covered doors) to alleviate the boundary effect for that wall. Two of the subwoofers are hidden in those cavities.

This became a huge advantage when I recently decided to wall mount the inverted Revel Salon2s to reduce their visual dominance - the huge loudspeakers retreat into the background visually, but remain firmly in place acoustically. The other loudspeakers in the room are clearly visible, which would be a deal breaker in many households. In this one, I am fortunate to have a wife who has long tolerated my hobby/profession, admitting that the audible rewards are enough to offset a certain amount of visual loudspeaker clutter. This system may have exceeded even those generous limits :-)

An in-ceiling loudspeaker is used as the Voice of God. Others could have replaced some or all of the elevation speakers. But, knowing that the direct sound has a dominant effect on timbre/sound quality I decided not to compromise, and used high quality bookshelf loudspeakers in custom mounts, aiming them at the prime listening location as shown in the following floor plan.



The prime listener is close to on-axis of most loudspeakers and within the listening window (±30° hor. ±10° vert.) of all loudspeakers. The base level surround loudspeakers are Revel Gem2s for unquestioned timbre matching to the Salon2s and Voice2 L, C, R array. With flexible seating it was important that bass quality not be location dependent so Sound Field Management (SFM) was employed. Subwoofers in the rear corners of the room complete the array of four. They are all closed box 1 kW units. All loudspeakers are bass managed; high-pass filtered at 80 Hz. This was a challenge for the Salon2s, which are truly full range, requiring additional high-pass filter slope to be added in the SDP-75 processor.

The large opening to the rest of the house eliminated the first sidewall reflection on that side, so heavy velour drapes were used on the opposite wall to provide balance by absorbing much of that sound. Opaque lining provided room darkening at the same time. There is much discussion of the importance of side wall reflections in my book. They have a significant effect in stereo listening, but are unimportant in multi-channel or up-mixed stereo listening. I choose to add moderate up-mixing to most of my stereo music, finding the adjustable Auro-3D implementation in the SDP-75 to be quite pleasant. This is where timbre matching of fronts and surrounds is most critical. Movie surround effects are more tolerant.

The Toole’s entertainment room: 2019 - the “nuts and bolts”

Starting with an existing room that is used for everyday living as well as quality audio and video entertainment presents challenges. However, there are solutions. In this case there was the advantage that loudspeakers could be visible - in this household they have long ago been accepted as necessary to deliver the highly rewarding sounds. I have attempted to “soften”the technical appearance, but obviously not completely. The equipment/projector space used to be a traditional fireplace which architects persist in putting in the wrong locations for modern entertainment. I had the room rotated 180° and a new fireplace constructed.

I concluded that there was no single speaker arrangement that can perfectly satisfy all playback modes, so this is a compromise, a Trinnov suggestion. Time and experience will tell how well it all works.

The locations of the ± 60° loudspeakers required some visual compromises: a table stand on the right counter-top and an inverted, elevated location on the left to avoid head banging. The sound is fine, but I would have wished for less obtrusive visuals. These locations are perceptually advantageous and I will be experimenting with arraying the ± 60° and ± 110° speakers using various levels and delays.

From the acoustical perspective, there are abundant absorbing and scattering surfaces and objects to bring the reverberation time down to a broadband 0.4 s - a widely accepted norm for listening spaces. Much of this is not obvious — a "stealth” acoustical treatment. Large areas of heavy velour drapes and an upper rear wall that has about 5 inches of fiberglass behind acoustically transparent fabric help. Large areas of books both absorb and scatter sound. Clipped pile carpet on thick felt underlay is also effective.

Suspending the elevation speakers in earthquake territory (California) required some serious custom metalwork and sturdy attachments to the speakers. Multiple screws into the pristine piano-black finish hurt, but the existing tie-downs to speaker stands were simply not strong enough.



The powerful projector generated noise, so a hush enclosure was designed, lined with human-friendly cotton “denim” absorbing material and ventilated to the attic using a quiet Panasonic FV-40NLF1 exhaust fan. Just as I dislike putting perforated screens in front of loudspeakers, I disliked the idea of putting even coated glass in front of the superb optics of the JVC projector.

A little investigation and some lateral thinking resulted in the solution shown below - an 8-inch PVC pipe coupler, cut on one side of the central ridge fits perfectly with a bit of sanding. It allows air to flow inside the box without leaking noise. The projector is inaudible in the room.



Equipment List and Photo Gallery (text continues below pics)











Left & Right Speakers: Revel Salon2 inverted

Center Speaker: Voice2

Above powered by 3 Mark Levinson 536s

Six surrounds: Revel Gem2s

Front and rear elevation: Revel M106s

Front center elevation: Revel C205

VOG: Revel C783

Power: JBL Synthesis SDA-7200 and Lexicon LX-7 (both 200 w/ch)

Audio processor: JBL Synthesis/Trinnov SDP75-24 set up to do Sound Field Management employing four JBL Synthesis HTPS-400s

Projector: JVC DLA-RS4500 4k laser

Screen: Stewart 127-inch Firehawk (selected for its ability to reject lateral light leakage during daytime viewing)

Video switching and processing: Lumagen Radiance Pro

Oppo UDP-203

Kaleidescape Strato

Roon Nucleus

Apple TV 4k, DirecTV

Assorted objets d’art - apparently bronze sculptures of the female form have special acoustical scattering abiities :-)

Room: 19 x 22.5 x 8-11 ft high. Listening distance 11 ft for stereo and for ideal immersive movie viewing, 14 to 16 ft for casual listening and viewing.

The original construction in 2000 and this upgrade in 2018 were possible because of my exceptional omni-talented builder Matt Fesler who did it all: rough carpentry, drywall and finish cabinetry, floor tile, granite fireplace, metal fabrication and welding, household electrical modifications, wire pulling and hookup, hush enclosure, extractor fan, etc. I did the drawings - he made it.

Component installation and basic configuration by Toole. Video calibration by Kris Deering. Lumagen guidance from Jim Peterson. SDP75 setup and acoustical calibration by Kevin Voecks (Harman). Sound Field Management optimization by Todd Welti (Harman). System advice and guidance from John Schuermann (The Screening Room) and Steve Silberman (Roon).

Thanks to all for services rendered, equipment supplied and jobs well done! Needless to say, the images and sound are very impressive. I am more than pleased!

Floyd Toole
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post #3325 of 3652 Old 03-13-2019, 02:49 PM
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Thanks John Schuermann . . .

Blush . . . It has been a while since I last read John's introduction. My ego is suitably inflated. Thanks for the kind words.

As might be anticipated, I am deeply gratified that all of my awards come from international professional industry organizations populated by people representing a who's who of audio manufacturers. These are people who have examined the published science, almost certainly evaluated it in their own facilities with their own products and found it useful. That is the highest reward for a research scientist.

It should be obvious that this is likely to be my last shot at creating a satisfying entertainment system - "you can't take it with you" and "enjoy it while you can (still hear)" were the folkloric thoughts in my mind. My previous system lasted 18 years. If this one does the same I'll be 98 years old, and may not care any more, or even be here. But, my father is now 106.5, so who knows . . .

In the meantime I am absolutely enjoying my new toy - with my wife's approval
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Originally Posted by Floyd Toole View Post
Blush . . . It has been a while since I last read John's introduction. My ego is suitably inflated. Thanks for the kind words.

As might be anticipated, I am deeply gratified that all of my awards come from international professional industry organizations populated by people representing a who's who of audio manufacturers. These are people who have examined the published science, almost certainly evaluated it in their own facilities with their own products and found it useful. That is the highest reward for a research scientist.

It should be obvious that this is likely to be my last shot at creating a satisfying entertainment system - "you can't take it with you" and "enjoy it while you can (still hear)" were the folkloric thoughts in my mind. My previous system lasted 18 years. If this one does the same I'll be 98 years old, and may not care any more, or even be here. But, my father is now 106.5, so who knows . . .

In the meantime I am absolutely enjoying my new toy - with my wife's approval
I'm glad to see it all worked out for you! I'll read in more detail later tonight.

Audio Gear: Trinnov Altitude 32 (24 channel), NAD M27 amps (3)
Video: JVC RS600, Seymour 100" UF Screen, Lumagen Radiance Pro 4444 (coming soon)
Speakers: PSB Imagine T3 LCR, Imagine T Wides/Side Surround 1, T2 Side Surrounds, Imagine XB rears, Image B6 screens, PSB CS1000 ceilings (6), HSU ULS-15 Mk 2 subs (4) - 13.4.6
HAA HT1 and HT2 Certification
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post #3327 of 3652 Old 03-13-2019, 05:15 PM
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Hi Floyd:

Wonderful wonderful wonderful. I really like that 8 inch PVC silencer for the JVC, and was wondering if you could elaborate a little more about that. I am installing a hushbox for my Sony 5000ES and would love to do the same type of glassless front.
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post #3328 of 3652 Old 03-13-2019, 06:17 PM
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Hi Floyd:

Wonderful wonderful wonderful. I really like that 8 inch PVC silencer for the JVC, and was wondering if you could elaborate a little more about that. I am installing a hushbox for my Sony 5000ES and would love to do the same type of glassless front.
It's not complicated. The PVC coupler conveniently fitted the lens surround - this was the "breakthrough". You will need to find a cylinder that fits the similar structure on your machine. It needs to be long enough to allow necessary airflow from the front of the PJ - i.e. the space between the front of the PJ and the inside of the enclosure through which the cylinder protrudes. You may need to consult your manufacturer. In my case there were optional air deflectors directing the exhaust air sideways. I simply allowed a bit more space than these occupied, and since the air could escape to the sides and above there was no problem. I monitor the temperature of the air at the intake at the rear of the PJ to ensure that the air within the hush box is not above the specified ambient temperature limit. It never gets close.
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post #3329 of 3652 Old 03-13-2019, 06:38 PM
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Originally Posted by Floyd Toole View Post
It's not complicated. The PVC coupler conveniently fitted the lens surround - this was the "breakthrough". You will need to find a cylinder that fits the similar structure on your machine. It needs to be long enough to allow necessary airflow from the front of the PJ - i.e. the space between the front of the PJ and the inside of the enclosure through which the cylinder protrudes. You may need to consult your manufacturer. In my case there were optional air deflectors directing the exhaust air sideways. I simply allowed a bit more space than these occupied, and since the air could escape to the sides and above there was no problem. I monitor the temperature of the air at the intake at the rear of the PJ to ensure that the air within the hush box is not above the specified ambient temperature limit. It never gets close.
Intakes are front sides, the exhaust is rear, plenty of room top, bottom and side inside front of hushbox design so this should work perfectly! Ingenious idea!
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post #3330 of 3652 Old 03-14-2019, 06:41 AM
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Wow! I don't know what else to say.
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