How to Choose a Loudspeaker -- What the Science Shows - Page 124 - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
 6394Likes
Reply
 
Thread Tools
post #3691 of 5323 Old 07-13-2019, 05:28 PM
Advanced Member
 
BP1Fanatic's Avatar
 
Join Date: Jan 2010
Location: Columbus, Oh
Posts: 667
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 228 Post(s)
Liked: 195
Lol!

Sony XBR65x900e / STR-DN1080 / original PS4 / WOW! Ultra TV / Quantum Access Mini PC Stick w/Windows 10 / 8 x Rockville SPG88 8“ DJ PA Speakers / Dayton Audio SA1000 / Kicker 08S15L74 in a Tapped-Tapered Quarter Wave Tube (negative flare tapped horn).
BP1Fanatic is offline  
Sponsored Links
Advertisement
 
post #3692 of 5323 Old 07-14-2019, 12:53 AM
AVS Forum Special Member
 
Molon_Labe's Avatar
 
Join Date: Jun 2015
Location: Texas
Posts: 2,261
Mentioned: 108 Post(s)
Tagged: 0 Thread(s)
Quoted: 3443 Post(s)
Liked: 4126
Quote:
Originally Posted by Floyd Toole View Post
It is interesting to contemplate that for "object-oriented" immersive sound it may be advantageous for sound quality if the channel count is reduced.
A bottle of your favorite wine if you post this in the Trinnov Altitude thread. I can literally see their heads exploding from the cognitive dissonance this statement would cause.
Molon_Labe is offline  
post #3693 of 5323 Old 07-14-2019, 04:26 AM
AVS Forum Special Member
 
Scotth3886's Avatar
 
Join Date: Jan 2016
Location: New Albany, OH
Posts: 8,230
Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 3998 Post(s)
Liked: 2465
Originally Posted by Floyd Toole
It is interesting to contemplate that for "object-oriented" immersive sound it may be advantageous for sound quality if the channel count is reduced

Quote:
Originally Posted by Molon_Labe View Post
A bottle of your favorite wine if you post this in the Trinnov Altitude thread. I can literally see their heads exploding from the cognitive dissonance this statement would cause.
To two.
Scotth3886 is online now  
Sponsored Links
Advertisement
 
post #3694 of 5323 Old 07-14-2019, 09:13 AM
AVS Forum Special Member
 
aarons915's Avatar
 
Join Date: Oct 2012
Location: Cincinnati, OH
Posts: 1,340
Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
Quoted: 899 Post(s)
Liked: 709
Quote:
Originally Posted by Dave in Green View Post
I've personally done a lot of experimentation with subwoofer placement and crossover frequencies. My experience has been that when the sub is located between the L/R at the front of the room it can be crossed over at higher frequencies than 80Hz without localization. When running small L/C/R I've crossed to the sub as high as 160Hz without localization. Obviously there are many variables including specific speaker/sub performance, precise speaker locations and individual sensitivity to low bass localization. So this can work for some people in some environments but not for others.
Quote:
Originally Posted by BP1Fanatic View Post
A few guys do that in car audio SQ competition when they put a sub in the footwell or dashboard. I've seen settings as high as 200hz without localization.
I agree with this but I also agree that for many people who don't want to measure and EQ their response, 80Hz is a good crossover. If you have a ragged sub response with peaks above 100Hz or your sub is 5-10 db higher than your mains, then localization could happen.

I was reading any study I could find on sub localization in the AES journals and summarized 4 of them in this thread:
https://www.avsforum.com/forum/91-au...n-studies.html

The lowest crossover frequency needed in any of the studies was 100Hz and not surprisingly, a single sub located in a corner was the easiest to localize, but still not at 100Hz crossover. A very early study made the claim that there is "Very little directional information below about 200Hz" and "none at all below about 100Hz."

I recently did my own little test in my room to check that claim, I use dual subs but I actually turned 1 off because it's easier to localize the bass laterally if the bass is coming from 1 source. I had to turn the crossover up to 250Hz before it was easy to localize. I was surprised that even at 200Hz I couldn't localize the bass or at least it wasn't easy to tell.

I personally use a 100hz 4th order crossover and wouldn't go higher than that though, mostly because it's not necessary in my opinion. Above 100hz the mains sound a bit too thin and I also don't want vocals coming from the sub, even if they aren't localized, it just feels wrong. 100Hz is about the highest I can go before I can hear the lower end of the vocals (with my mains off). If I had towers, I would most likely cross at 80Hz but I think those of us with single driver bookshelf speakers are better off at 100Hz. This is all with 4th order slopes, if had a receiver with a 2nd order high pass, I would be at 120Hz probably.
Soulburner and SouthernCA like this.
aarons915 is online now  
post #3695 of 5323 Old 07-14-2019, 09:31 AM
AVS Forum Special Member
 
Scotth3886's Avatar
 
Join Date: Jan 2016
Location: New Albany, OH
Posts: 8,230
Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 3998 Post(s)
Liked: 2465
Quote:
Originally Posted by aarons915 View Post
I agree with this but I also agree that for many people who don't want to measure and EQ their response, 80Hz is a good crossover. If you have a ragged sub response with peaks above 100Hz or your sub is 5-10 db higher than your mains, then localization could happen.

I was reading any study I could find on sub localization in the AES journals and summarized 4 of them in this thread:
https://www.avsforum.com/forum/91-au...n-studies.html

The lowest crossover frequency needed in any of the studies was 100Hz and not surprisingly, a single sub located in a corner was the easiest to localize, but still not at 100Hz crossover. A very early study made the claim that there is "Very little directional information below about 200Hz" and "none at all below about 100Hz."

I recently did my own little test in my room to check that claim, I use dual subs but I actually turned 1 off because it's easier to localize the bass laterally if the bass is coming from 1 source. I had to turn the crossover up to 250Hz before it was easy to localize. I was surprised that even at 200Hz I couldn't localize the bass or at least it wasn't easy to tell.

I personally use a 100hz 4th order crossover and wouldn't go higher than that though, mostly because it's not necessary in my opinion. Above 100hz the mains sound a bit too thin and I also don't want vocals coming from the sub, even if they aren't localized, it just feels wrong. 100Hz is about the highest I can go before I can hear the lower end of the vocals (with my mains off). If I had towers, I would most likely cross at 80Hz but I think those of us with single driver bookshelf speakers are better off at 100Hz. This is all with 4th order slopes, if had a receiver with a 2nd order high pass, I would be at 120Hz probably.
Here's a good test recording. Bassist Freeman is off center to the left by about 30 degrees. There's an alto further left of him and then Freeman. If you don't hear him in the subs you're good to go with everything else I can think of. He can go as low or lower than anyone else I've heard. True, Tim Storms can likely go lower, but I was looking for someone singing off center to see if that image holds when he goes down there and it remains off center to the left or the subs drag it back to center. (why I use stereo subs)

https://tidal.com/browse/track/80666461

views 1087

aarons915 and Karl Maga like this.

Last edited by Scotth3886; 07-14-2019 at 09:48 AM.
Scotth3886 is online now  
post #3696 of 5323 Old 07-14-2019, 10:21 AM
Advanced Member
 
motrek's Avatar
 
Join Date: Dec 2013
Posts: 653
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 518 Post(s)
Liked: 191
Quote:
Originally Posted by Soulburner View Post
The more I learn, the more I wonder about my Infinity Primus P362s, my first "real" speakers. As I noted previously, I never noticed that they weren't really neutral or natural sounding for the 4 years I listened to them, until I put them side to side with another speaker. Then, it became very obvious that the sound was a lot more...trebly. Now the competing speaker was not neutral either, but it reminded me of the sound you get when you cranked the treble knob on my Dad's old stereo. My mind had completely adapted to its sound as it was the only speaker I was hearing, and I did not have experienced ears. Since most people praise those speakers, at least for their very low cost, it had to be cabinet resonances coloring the sound. In fact, I read quite a few posts about efforts to improve bracing on the Primus line, especially the towers, and how big of a difference it made. I never did try that.
I remember reading a lot about the Primus speakers since they were the predecessors to the Infinitys that I own now. This issue with the treble is kind of confusing.

Stereophile measured the P360 and it was crazy flat:
https://www.stereophile.com/content/...r-measurements

Audioholics measured the P363 and it only had a slight upward tilt towards ~10k:
https://www.audioholics.com/tower-sp...3-measurements

The spin-o-rama plot from Harman looks nearly perfect and I believe Dr. Toole uses this speaker in his slide decks as a reference "accurate" speaker that wins double-blind listening tests:
https://speakerdata2034.blogspot.com...rama-data.html

So none of the measurements seem to suggest any treble bias. But if you look at measurements of the bookshelves, there's a huge +4 or +5 dB hump centered around ~13 kHz on-axis. This reviewer suggests listening below the tweeter axis to reduce the treble:
http://averagejoeaudiophile.blogspot...ments-and.html

This reviewer also measures a huge treble bump (in-room, but not close-mic for some reason?!) and complains about tweeter "shrillness":
http://noaudiophile.com/Infinity_P163/

So I'm not really sure what happened here. You, and other people, report that the floorstanders have shrill/unrealistic/elevated treble but they seem to measure great.

Meanwhile, the bookshelves, that seem to use the same tweeter and presumably have a similar crossover design and components, have a huge, easily-measured high-frequency bump and everybody seems to agree that they have harsh treble. (Actually I'm not sure how these speakers made it out of the Harman design process?!)

So why does this bookshelf problem exist and why does it seem to be audible with the floorstanders but not measurable?

I'm especially curious because I feel that my floorstanders sometimes have harsh treble but there's nothing about their frequency response that would suggest that:
https://hometheaterreview.com/measur...d-full/?page=2

Last edited by motrek; 07-14-2019 at 10:26 AM.
motrek is offline  
post #3697 of 5323 Old 07-14-2019, 10:35 AM
Senior Member
 
Join Date: Apr 2019
Posts: 232
Mentioned: 10 Post(s)
Tagged: 1 Thread(s)
Quoted: 238 Post(s)
Liked: 661
Hi Dr. Toole

I've been an avid reader of Consumer Reports most of my life (I have a collection dating back pre-World War II), and in general I've found the ratings to be fairly reliable and unbiased. One glaring exception is loudspeakers, as you have noted. I could never figure out exactly how they were deriving their accuracy score. The way they described it, the measurements seemed very similar to the Spinorama, in that they claimed to be measuring speakers from all angles, including the rear. (They never disclosed whether the individual plots were weighted, if at all.) Yet the resulting overall frequency response looked far too flat in the upper treble to include far off-axis measurements, let alone information obtained from behind the speakers. Way back in the day, I bought a pair Zenith speakers that had produced one of the highest accuracy scores on record. They were God-Awful. Since you discussed the rating protocol with Consumer Reports staff, could you briefly describe how the accuracy scores were derived, and what you thought were the major flaws in the methodology? I've been wondering about this for decades. Thanks very much.

Last edited by PhilharmonicDennis; 07-14-2019 at 10:40 AM.
PhilharmonicDennis is offline  
post #3698 of 5323 Old 07-14-2019, 11:06 AM
Member
 
Join Date: Apr 2019
Posts: 16
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Liked: 13
Quote:
Originally Posted by PhilharmonicDennis View Post
Hi Dr. Toole
They were God-Awful. Since you discussed the rating protocol with Consumer Reports staff, could you briefly describe how the accuracy scores were derived, and what you thought were the major flaws in the methodology? I've been wondering about this for decades. Thanks very much.
Dr Toole has touched on this in one of his earlier posts. (Sorry, I need one more post to have clickable links.)
[avsforum.com/forum/89-speakers/3038828-how-choose-loudspeaker-what-science-shows-112.html#post58265318]
NTK-129 is offline  
post #3699 of 5323 Old 07-14-2019, 11:14 AM
Senior Member
 
Join Date: Apr 2019
Posts: 232
Mentioned: 10 Post(s)
Tagged: 1 Thread(s)
Quoted: 238 Post(s)
Liked: 661
Quote:
Originally Posted by NTK-129 View Post
Dr Toole has touched on this in one of his earlier posts. (Sorry, I need one more post to have clickable links.)
[avsforum.com/forum/89-speakers/3038828-how-choose-loudspeaker-what-science-shows-112.html#post58265318]
Thanks. Now I remember seeing that, but I'm hoping Dr. Toole can add a little detail concerning how those measurements were weighted and what were the major misconceptions concerning human perception of sound.
PhilharmonicDennis is offline  
post #3700 of 5323 Old 07-14-2019, 11:17 AM
Advanced Member
 
motrek's Avatar
 
Join Date: Dec 2013
Posts: 653
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 518 Post(s)
Liked: 191
Quote:
Originally Posted by PhilharmonicDennis View Post
Thanks. Now I remember seeing that, but I'm hoping Dr. Toole can add a little detail concerning how those measurements were weighted and what were the major misconceptions concerning human perception of sound.

Check out this presentation starting at 50:35.

EDIT: Whoops, I see that this video doesn't give any more information than Dr. Toole's earlier post about this to this thread. Well, interesting talk either way.

Last edited by motrek; 07-14-2019 at 12:04 PM.
motrek is offline  
post #3701 of 5323 Old 07-14-2019, 12:22 PM
AVS Forum Special Member
 
Soulburner's Avatar
 
Join Date: Oct 2007
Location: Lincoln
Posts: 4,904
Mentioned: 47 Post(s)
Tagged: 0 Thread(s)
Quoted: 194 Post(s)
Liked: 1636
Quote:
Originally Posted by aarons915 View Post
I personally use a 100hz 4th order crossover and wouldn't go higher than that though, mostly because it's not necessary in my opinion. Above 100hz the mains sound a bit too thin and I also don't want vocals coming from the sub, even if they aren't localized, it just feels wrong. 100Hz is about the highest I can go before I can hear the lower end of the vocals (with my mains off). If I had towers, I would most likely cross at 80Hz but I think those of us with single driver bookshelf speakers are better off at 100Hz. This is all with 4th order slopes, if had a receiver with a 2nd order high pass, I would be at 120Hz probably.
Very similar here - 100Hz LR4. Are you sure about that last sentence, though? It is the steeper slope that enables higher crossovers to be used, in my system. At least in terms of preventing the sub from playing up beyond 300Hz, you need the faster rolloff of the LR4 to kill it by 200Hz.

A problem a shallow slope creates is sounds that should be playing only through your main speakers, optimally positioned, will come from boxes on the floor. If you have stereo subs, that's not going to be as optimal as cutting off your subs quicker and letting your proper speakers handle those frequencies. It is the beyond 200Hz content that will start to be directional and sound like it's coming from a cardboard box somewhere in the room, especially if your subs are along the walls, optimally placed for bass.

In your example, a 120Hz crossover with a 2nd order will only be down by 12dB at 240Hz!

HT: Samsung PN64H5000 (recommended settings) | NAD T758 V3 | Buchardt S400 (2) | Emotiva E2 (2) | Rythmik Audio F12 (2)

Last edited by Soulburner; 07-14-2019 at 12:44 PM.
Soulburner is offline  
post #3702 of 5323 Old 07-14-2019, 12:32 PM
AVS Forum Special Member
 
Soulburner's Avatar
 
Join Date: Oct 2007
Location: Lincoln
Posts: 4,904
Mentioned: 47 Post(s)
Tagged: 0 Thread(s)
Quoted: 194 Post(s)
Liked: 1636
Quote:
Originally Posted by Scotth3886 View Post
Here's a good test recording. Bassist Freeman is off center to the left by about 30 degrees. There's an alto further left of him and then Freeman. If you don't hear him in the subs you're good to go with everything else I can think of. He can go as low or lower than anyone else I've heard. True, Tim Storms can likely go lower, but I was looking for someone singing off center to see if that image holds when he goes down there and it remains off center to the left or the subs drag it back to center. (why I use stereo subs)
Because he doesn't sing in just one non-localizable frequency - his voice includes higher harmonics that will image, correct? And, wouldn't your speakers be better at that?
motrek likes this.

HT: Samsung PN64H5000 (recommended settings) | NAD T758 V3 | Buchardt S400 (2) | Emotiva E2 (2) | Rythmik Audio F12 (2)

Last edited by Soulburner; 07-14-2019 at 12:45 PM.
Soulburner is offline  
post #3703 of 5323 Old 07-14-2019, 12:38 PM
AVS Forum Special Member
 
Soulburner's Avatar
 
Join Date: Oct 2007
Location: Lincoln
Posts: 4,904
Mentioned: 47 Post(s)
Tagged: 0 Thread(s)
Quoted: 194 Post(s)
Liked: 1636
Quote:
Originally Posted by motrek View Post
I remember reading a lot about the Primus speakers since they were the predecessors to the Infinitys that I own now. This issue with the treble is kind of confusing.

Stereophile measured the P360 and it was crazy flat:
https://www.stereophile.com/content/...r-measurements

Audioholics measured the P363 and it only had a slight upward tilt towards ~10k:
https://www.audioholics.com/tower-sp...3-measurements

The spin-o-rama plot from Harman looks nearly perfect and I believe Dr. Toole uses this speaker in his slide decks as a reference "accurate" speaker that wins double-blind listening tests:
https://speakerdata2034.blogspot.com...rama-data.html

So none of the measurements seem to suggest any treble bias. But if you look at measurements of the bookshelves, there's a huge +4 or +5 dB hump centered around ~13 kHz on-axis. This reviewer suggests listening below the tweeter axis to reduce the treble:
http://averagejoeaudiophile.blogspot...ments-and.html

This reviewer also measures a huge treble bump (in-room, but not close-mic for some reason?!) and complains about tweeter "shrillness":
http://noaudiophile.com/Infinity_P163/

So I'm not really sure what happened here. You, and other people, report that the floorstanders have shrill/unrealistic/elevated treble but they seem to measure great.

Meanwhile, the bookshelves, that seem to use the same tweeter and presumably have a similar crossover design and components, have a huge, easily-measured high-frequency bump and everybody seems to agree that they have harsh treble. (Actually I'm not sure how these speakers made it out of the Harman design process?!)

So why does this bookshelf problem exist and why does it seem to be audible with the floorstanders but not measurable?

I'm especially curious because I feel that my floorstanders sometimes have harsh treble but there's nothing about their frequency response that would suggest that:
https://hometheaterreview.com/measur...d-full/?page=2
All very interesting. So you're hearing something similar? And others have corroborated this, too? If I had them again I could do a better head-to-head today.

What's interesting is that the EMP Impressions speakers I compared them to are known to have a rolled-off tweeter beyond 10K and an elevated upper midrange, noted in measurements and by ear, however they sounded much better. So it is puzzling to me, for sure. I don't know where else to point the blame than cabinet resonances or maybe the dispersion somehow interacting badly with my room.

HT: Samsung PN64H5000 (recommended settings) | NAD T758 V3 | Buchardt S400 (2) | Emotiva E2 (2) | Rythmik Audio F12 (2)
Soulburner is offline  
post #3704 of 5323 Old 07-14-2019, 12:40 PM
Senior Member
 
highmr's Avatar
 
Join Date: Mar 2010
Location: Scottsdale, Arizona
Posts: 241
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 107 Post(s)
Liked: 67
Quote:
Originally Posted by PhilharmonicDennis View Post
Hi Dr. Toole

I've been an avid reader of Consumer Reports most of my life (I have a collection dating back pre-World War II), and in general I've found the ratings to be fairly reliable and unbiased. One glaring exception is loudspeakers, as you have noted. I could never figure out exactly how they were deriving their accuracy score. The way they described it, the measurements seemed very similar to the Spinorama, in that they claimed to be measuring speakers from all angles, including the rear. (They never disclosed whether the individual plots were weighted, if at all.) Yet the resulting overall frequency response looked far too flat in the upper treble to include far off-axis measurements, let alone information obtained from behind the speakers. Way back in the day, I bought a pair Zenith speakers that had produced one of the highest accuracy scores on record. They were God-Awful. Since you discussed the rating protocol with Consumer Reports staff, could you briefly describe how the accuracy scores were derived, and what you thought were the major flaws in the methodology? I've been wondering about this for decades. Thanks very much.
In his book he says they measured sound power in an anechoic setting, then compared this to an ideal curve based on some sort of preference work (not disclosed by CU). Also, 110 Hz to 14 kHz, and at 1/3 octave bands.

My comments: Depending on the ideal curve specified, the sound power approach could put preference on speakers that are either rising more or less with frequency than a flat in-room or anechoic listening window approach (not sure which). Smoothness of this curve would be preferred by their method, but at those 1/3 octave levels of detail.

Living room: Samsung PN60F8500, Sony X800M2, Roku Premiere+, Revel W763, Revel M16, Hsu HB-1 MK2, RSL C34E, Rhythmik D15SE, Denon X4200W; Zone 2: Speaker selector, Yamaha RX-V495 (1999); Bedroom: Panasonic P50U54, Oppo BDP-80, Chromecast Audio, Advent Legacy III (1994), Denon 2310ci; Cabin: Roku 3, NHT Super Zero (1996), Hsu VTF-2 MK4, Denon 1712
highmr is offline  
post #3705 of 5323 Old 07-14-2019, 01:23 PM
Senior Member
 
Join Date: Apr 2019
Posts: 232
Mentioned: 10 Post(s)
Tagged: 1 Thread(s)
Quoted: 238 Post(s)
Liked: 661
Quote:
Originally Posted by highmr View Post
In his book he says they measured sound power in an anechoic setting, then compared this to an ideal curve based on some sort of preference work (not disclosed by CU). Also, 110 Hz to 14 kHz, and at 1/3 octave bands.

My comments: Depending on the ideal curve specified, the sound power approach could put preference on speakers that are either rising more or less with frequency than a flat in-room or anechoic listening window approach (not sure which). Smoothness of this curve would be preferred by their method, but at those 1/3 octave levels of detail.
Thanks. That's very interesting. What's confusing me is that they used to show the frequency response for each speaker, and the ratings appear to be based on this curve alone.
PhilharmonicDennis is offline  
post #3706 of 5323 Old 07-14-2019, 01:40 PM
Member
 
Floyd Toole's Avatar
 
Join Date: Jun 2017
Location: California
Posts: 837
Mentioned: 89 Post(s)
Tagged: 0 Thread(s)
Quoted: 876 Post(s)
Liked: 3083
Quote:
Originally Posted by PhilharmonicDennis View Post
Thanks. Now I remember seeing that, but I'm hoping Dr. Toole can add a little detail concerning how those measurements were weighted and what were the major misconceptions concerning human perception of sound.
How Consumer Reports came to their ratings remains something of a mystery. I got access to some, but not all of the process many years ago. It was incomplete, but enough to see why their ratings could not be right. They published one or two articles in audio mags decades ago, no useful details. I have the references buried in files somewhere.

They had an anechoic chamber - don't know how good, because when we showed how wrong they were they said they needed a new one. In it they measured 1/3-octave resolution frequency responses at points on a sphere enabling an estimate of total radiated sound power. This, they assumed, was the key factor in what we hear in rooms - wrong, because domestic rooms are not reverberation chambers, and 1/3-octave resolution is not adequate (I was using 1/20-octave then and still). This was an idea then promoted by a few east coast audio people.

Sound power is one of the processed curves in a spinorama presentation but it is not one that correlates well with sound quality.

Then they processed the data above some frequency - 150 Hz comes to mind - to generate a 1/3-octave band curve measured in sones, the metric for subjective loudness. This cannot work for broadband sounds evaluated for timbral accuracy. There was more to it, having to do with bass I think, but I have not tried to remember bad science, only good stuff. I visited them before joining Harman and saw where they did the subjective tests in support of their method. It was a large, high ceilinged concrete room with what seemed like canvas drapes on some of the walls with dozens of folding chairs. It was quite live. As described to me staff would assemble there at lunch time and while munching sandwiches listen and make ratings.

The first time I encountered the people at CU was at a meeting of loudspeaker designers and researchers I organized at the NRCC in the mid '80s. Knowing they were coming I put together an overhead transparency showing our double-blind subjective evaluations on four loudspeakers that they also had rated. The correlation was -0.7 (that's minus, meaning that to interpret their ratings one must invert the page). Many years later Sean Olive did his benchmark correlations and he found a correlation coefficient of - 0.22. This needs to be compared to Olive's correlation of 0.995 with a very high statistical significance. The best loudspeaker in our evaluations ranked lowest in theirs. This is all described in Olive's papers and summarized in my book.

The people at CU were nice, earnest and truly believed in their method. I never found out who was responsible for creating it, but I have some suspicions. It was a long time ago . . . best forgotten.
Muza, vavan, duckymomo and 1 others like this.
Floyd Toole is offline  
post #3707 of 5323 Old 07-14-2019, 01:48 PM
Advanced Member
 
motrek's Avatar
 
Join Date: Dec 2013
Posts: 653
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 518 Post(s)
Liked: 191
Quote:
Originally Posted by Soulburner View Post
All very interesting. So you're hearing something similar? And others have corroborated this, too? If I had them again I could do a better head-to-head today.

What's interesting is that the EMP Impressions speakers I compared them to are known to have a rolled-off tweeter beyond 10K and an elevated upper midrange, noted in measurements and by ear, however they sounded much better. So it is puzzling to me, for sure. I don't know where else to point the blame than cabinet resonances or maybe the dispersion somehow interacting badly with my room.
Definitely everybody seemed to agree that the higher frequencies were harsh with the Primus bookshelves, and it was obvious from everybody's measurements that they had a big high-frequency bump.

The Primus floorstanders measured great but you're not the first person to say that they had harsh tweeters. I've seen that posted before and if you look at the conclusion of the Audioholics review they say the P363 was "voiced hot" although their measurements only show a ~2.5 dB bump.

So I don't really know what's going on with all that.

I have the Infinity Reference R253 floorstanders which are the successors to the Primus line and they're supposed to be higher-end. Almost everything about the design is different, but especially the tweeters. The waveguide and acoustic lens are completely different. The crossover is 1.8 kHz instead of 3.3 kHz. If you look at the backs of the tweeters, the Primus tweeter is a piddly little thing whereas the Reference tweeter is in an enormous polished enclosure. (Who knows what's inside the enclosure...)

So it seems like they shouldn't be similar at all but I do feel like the treble is harsh sometimes. Not all the time. But like the leading edges of some sounds are "crunchy."
motrek is offline  
post #3708 of 5323 Old 07-14-2019, 02:22 PM
AVS Forum Special Member
 
Scotth3886's Avatar
 
Join Date: Jan 2016
Location: New Albany, OH
Posts: 8,230
Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 3998 Post(s)
Liked: 2465
Quote:
Originally Posted by Soulburner View Post
Because he doesn't sing in just one non-localizable frequency - his voice includes higher harmonics that will image, correct? And, wouldn't your speakers be better at that?
I have stereo subs in the downstairs system. I have a mono sub in the system up stairs. Image is sharper, more defined and placed more precisely in the system with stereo subs.
Scotth3886 is online now  
post #3709 of 5323 Old 07-14-2019, 02:25 PM
AVS Forum Special Member
 
Scotth3886's Avatar
 
Join Date: Jan 2016
Location: New Albany, OH
Posts: 8,230
Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 3998 Post(s)
Liked: 2465
Quote:
Originally Posted by Floyd Toole View Post
How Consumer Reports came to their ratings remains something of a mystery. I got access to some, but not all of the process many years ago. It was incomplete, but enough to see why their ratings could not be right. They published one or two articles in audio mags decades ago, no useful details. I have the references buried in files somewhere.

They had an anechoic chamber - don't know how good, because when we showed how wrong they were they said they needed a new one. In it they measured 1/3-octave resolution frequency responses at points on a sphere enabling an estimate of total radiated sound power. This, they assumed, was the key factor in what we hear in rooms - wrong, because domestic rooms are not reverberation chambers, and 1/3-octave resolution is not adequate (I was using 1/20-octave then and still). This was an idea then promoted by a few east coast audio people.

Sound power is one of the processed curves in a spinorama presentation but it is not one that correlates well with sound quality.

Then they processed the data above some frequency - 150 Hz comes to mind - to generate a 1/3-octave band curve measured in sones, the metric for subjective loudness. This cannot work for broadband sounds evaluated for timbral accuracy. There was more to it, having to do with bass I think, but I have not tried to remember bad science, only good stuff. I visited them before joining Harman and saw where they did the subjective tests in support of their method. It was a large, high ceilinged concrete room with what seemed like canvas drapes on some of the walls with dozens of folding chairs. It was quite live. As described to me staff would assemble there at lunch time and while munching sandwiches listen and make ratings.

The first time I encountered the people at CU was at a meeting of loudspeaker designers and researchers I organized at the NRCC in the mid '80s. Knowing they were coming I put together an overhead transparency showing our double-blind subjective evaluations on four loudspeakers that they also had rated. The correlation was -0.7 (that's minus, meaning that to interpret their ratings one must invert the page). Many years later Sean Olive did his benchmark correlations and he found a correlation coefficient of - 0.22. This needs to be compared to Olive's correlation of 0.995 with a very high statistical significance. The best loudspeaker in our evaluations ranked lowest in theirs. This is all described in Olive's papers and summarized in my book.

The people at CU were nice, earnest and truly believed in their method. I never found out who was responsible for creating it, but I have some suspicions. It was a long time ago . . . best forgotten.
Amar Bose?
18Hurts and duckymomo like this.
Scotth3886 is online now  
post #3710 of 5323 Old 07-14-2019, 03:12 PM
Senior Member
 
Join Date: Apr 2019
Posts: 232
Mentioned: 10 Post(s)
Tagged: 1 Thread(s)
Quoted: 238 Post(s)
Liked: 661
Thanks very much Dr. Toole. That was very helpful. I didn't know that your Soundpower measurement isn't very predictive of subjective rankings. That doesn't surprise me given my own experience with various measurements and perceived speaker quality. Consumer Reports was obviously over their heads when it came to loudspeakers, and now I have a better idea why.
PhilharmonicDennis is offline  
post #3711 of 5323 Old 07-14-2019, 03:39 PM
AVS Forum Special Member
 
Scotth3886's Avatar
 
Join Date: Jan 2016
Location: New Albany, OH
Posts: 8,230
Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 3998 Post(s)
Liked: 2465
Music Break !!!!

Credit goes to DonH50 on this that he just posted in the Magnepan Forum. Hot Damn this is kickass big band

https://tidal.com/browse/album/110588238


It's on spotify too and iTunes.
Scotth3886 is online now  
post #3712 of 5323 Old 07-14-2019, 04:04 PM
AVS Forum Special Member
 
laserjock II's Avatar
 
Join Date: Sep 2003
Location: Texas Coast
Posts: 2,604
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1300 Post(s)
Liked: 737
Quote:
Originally Posted by Scotth3886 View Post
Music Break !!!!

Credit goes to DonH50 on this that he just posted in the Magnepan Forum. Hot Damn this is kickass big band

https://tidal.com/browse/album/110588238

https://youtu.be/NYyFBLQhBGM

It's on spotify too and iTunes.
I found it in Tidal too.

Listening now.

Key search word was Boptism

Edit: Didn’t notice the link to Tidal until now but I couldn’t get the search to work for It until I put Boptism in.

Last edited by laserjock II; 07-14-2019 at 04:11 PM.
laserjock II is offline  
post #3713 of 5323 Old 07-14-2019, 04:15 PM
AVS Forum Special Member
 
aarons915's Avatar
 
Join Date: Oct 2012
Location: Cincinnati, OH
Posts: 1,340
Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
Quoted: 899 Post(s)
Liked: 709
Quote:
Originally Posted by Soulburner View Post
Very similar here - 100Hz LR4. Are you sure about that last sentence, though? It is the steeper slope that enables higher crossovers to be used, in my system. At least in terms of preventing the sub from playing up beyond 300Hz, you need the faster rolloff of the LR4 to kill it by 200Hz.
Yes but I'm talking about the typical receiver that uses a THX crossover, so 2nd order high pass on the mains and 4th order low pass on the sub. I think the biggest problem with higher crossovers is the sub rolloff, in my case I added a 1st order lowpass at 100hz so my subs are actually rolling off at 30 db/octave to prevent higher frequencies from coming through.
Soulburner likes this.
aarons915 is online now  
post #3714 of 5323 Old 07-14-2019, 05:39 PM
AVS Forum Special Member
 
Scotth3886's Avatar
 
Join Date: Jan 2016
Location: New Albany, OH
Posts: 8,230
Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 3998 Post(s)
Liked: 2465
Quote:
Originally Posted by laserjock II View Post
I found it in Tidal too.

Listening now.

Key search word was Boptism

Edit: Didn’t notice the link to Tidal until now but I couldn’t get the search to work for It until I put Boptism in.
Tidal's search engine leave much to be desired.

That said, this is the best sounding big band album I've heard. I don't think I have anything moar better.
Scotth3886 is online now  
post #3715 of 5323 Old 07-14-2019, 09:23 PM
AVS Forum Special Member
 
laserjock II's Avatar
 
Join Date: Sep 2003
Location: Texas Coast
Posts: 2,604
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1300 Post(s)
Liked: 737
Quote:
Originally Posted by Scotth3886 View Post
Tidal's search engine leave much to be desired.

That said, this is the best sounding big band album I've heard. I don't think I have anything moar better.
Agree. Liked it even on the M106’s with subs
Scotth3886 likes this.
laserjock II is offline  
post #3716 of 5323 Old 07-14-2019, 10:20 PM
AVS Forum Special Member
 
Soulburner's Avatar
 
Join Date: Oct 2007
Location: Lincoln
Posts: 4,904
Mentioned: 47 Post(s)
Tagged: 0 Thread(s)
Quoted: 194 Post(s)
Liked: 1636
Quote:
Originally Posted by aarons915 View Post
Yes but I'm talking about the typical receiver that uses a THX crossover, so 2nd order high pass on the mains and 4th order low pass on the sub. I think the biggest problem with higher crossovers is the sub rolloff, in my case I added a 1st order lowpass at 100hz so my subs are actually rolling off at 30 db/octave to prevent higher frequencies from coming through.
As long as your speakers are up to the task to pick up the midbass, it's a wise choice. Here's a graph I've posted a few times in the Rythmik thread using various slope settings:

Click image for larger version

Name:	Slope Testing.png
Views:	42
Size:	67.4 KB
ID:	2590866

The reason I started testing was because the steeper slope sounded better. The graph explained why. The limited bandwidth above 80Hz did make the crossover a bit trickier, but overall it was worth it - the sub is effectively dead by 200Hz.

HT: Samsung PN64H5000 (recommended settings) | NAD T758 V3 | Buchardt S400 (2) | Emotiva E2 (2) | Rythmik Audio F12 (2)

Last edited by Soulburner; 07-14-2019 at 10:24 PM.
Soulburner is offline  
post #3717 of 5323 Old 07-14-2019, 10:59 PM
Advanced Member
 
l0nestar8's Avatar
 
Join Date: Sep 2009
Posts: 983
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 606 Post(s)
Liked: 717
Some thoughts on Primus and sub crossovers based on my experiences:

I used to own an Infinity Primus system (362's and 152's.) I bought them because of their measured accuracy and because I hated my Polk Monitor II's. I sold them fast because the tweeters were horrible. They had the classic metallic "zing" sound that was always irritating.

As for sub crossover points, I many times have performed my own experiments. In all cases it was single corner placement. I played a bass test tone through the sub and nearest front channel. I put my head right between the two and flipped the crossover points on my AVR until I could localize. In every case, I could localize at 90Hz and higher, and it wasn't difficult to hear at all. This was my "very worst case scenario."

At 90Hz I could easily hear the bass shift slightly towards the sub. At 80Hz (and lower) the bass just sounded all around me while the sub, seemingly by magic, disappeared. It was quite ear-opening to me how well-chosen the standard 80Hz was/is.

Now, I don't know what slope my AVR uses and this wasn't at the MLP. Using a higher order slope and judged from my MLP, a higher crossover point could most likely be used with little effect, but again, I was testing for "worst case" and my OCD told me to just keep it at 80Hz.

Speakers: M040 | X18 | UB5
Sub: VTF-2 mk5
Amps: HK 3490 | TSR-7810

Last edited by l0nestar8; 07-14-2019 at 11:11 PM.
l0nestar8 is online now  
post #3718 of 5323 Old 07-15-2019, 04:56 AM
AVS Forum Addicted Member
 
DonH50's Avatar
 
Join Date: Feb 2010
Location: Monument CO
Posts: 12,346
Mentioned: 69 Post(s)
Tagged: 0 Thread(s)
Quoted: 3276 Post(s)
Liked: 3365
I have generally prefered higher-order crossovers but they can be harder to align. Still, remember an octave (factor of two) away from the crossover, at 12 dB/oct the respective signals are at about half-loudness or so, louder for the sub side (where the loudness curves compress). That means your sub has significant energy an octave above the crossover, and mains an octave below, partly why I advocate for larger mains that stay controlled and clean well below the crossover point. And similarly advocate for setting the crossover an octave above the main's -3 dB point as a rough guideline.

Off topic: replicating the post from the Magnepan thread for the big band CD. Rich is a friend of mine (from the trumpet forum I help moderate), a great player in his own right, and has assembled a killer big band with top talent. In my opinion! - Don
---
Gotta' plug a new CD from a friend: https://www.boptism.com/down-and-dirty/
https://rootsmusicreport.com/charts/...re/jazz/weekly

Pretty killer modern big band sound, though I admit I've been listening more to the music than the gear.

Disclaimer: I know Rich and have at least met most of the rest of the guys on this album.
Vergiliusm likes this.

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
DonH50 is online now  
post #3719 of 5323 Old 07-15-2019, 07:39 AM
AVS Forum Special Member
 
Join Date: Mar 2017
Posts: 1,402
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 956 Post(s)
Liked: 290
Quote:
Originally Posted by Soulburner View Post
As long as your speakers are up to the task to pick up the midbass, it's a wise choice. Here's a graph I've posted a few times in the Rythmik thread using various slope settings:



Attachment 2590866



The reason I started testing was because the steeper slope sounded better. The graph explained why. The limited bandwidth above 80Hz did make the crossover a bit trickier, but overall it was worth it - the sub is effectively dead by 200Hz.
Not sure if it is my monitor, but I could not read any legend on the graph. What were these three slopes were?
SouthernCA is online now  
post #3720 of 5323 Old 07-15-2019, 07:53 AM
AVS Forum Special Member
 
Soulburner's Avatar
 
Join Date: Oct 2007
Location: Lincoln
Posts: 4,904
Mentioned: 47 Post(s)
Tagged: 0 Thread(s)
Quoted: 194 Post(s)
Liked: 1636
Quote:
Originally Posted by SouthernCA View Post
Not sure if it is my monitor, but I could not read any legend on the graph. What were these three slopes were?
In order from steep to shallow:

Line-In, 24dB slope
Line-In, 12dB
LFE-In, 12dB

HT: Samsung PN64H5000 (recommended settings) | NAD T758 V3 | Buchardt S400 (2) | Emotiva E2 (2) | Rythmik Audio F12 (2)
Soulburner is offline  
Sponsored Links
Advertisement
 
Reply Speakers

Tags
cea 2034 , double-blind , listening tests , loudspeaker measurements , spinorama

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off