100 dB or higher on a bright speaker vs. a warm speaker - Page 6 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #151 of 173 Old 05-17-2009, 04:39 AM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Quote:
Originally Posted by syswei View Post

If a good horn driver has inaudible distortion as compared to a good conventional driver, then (a) why are horn systems not in wider use in home environments, where efficiency is less critical, and (b) why does JBLs pro division, which sells both horn and conventional driver systems, not sell horn-based systems in the most critical-listening application, namely studio monitoring?
http://www.jblpro.com/products/recor...ast/index.html

My suspicion remains that there is a tradeoff involved...efficiency for distortion.

critical listening, studio monitoring does not need HUGE SPL so there are great designs out there plus these applications are less dependant on room interaction because you sit much close to the speakers.

Its an apples to oranges comparison.

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
Sponsored Links
Advertisement
 
post #152 of 173 Old 05-17-2009, 05:37 AM
AVS Special Member
 
syswei's Avatar
 
Join Date: May 2005
Location: CT
Posts: 1,100
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Drew Eckhardt View Post

distortion dB = 20 log (distortion percent / 100)
distortion percent = 100 * 10 ^ (distortion dB / 20)

Lambda unity (it's a mid-tweeter assembly intended to be crossed over to separate woofers at 300Hz)

Distortion @ 112dB/1M
.477% = -46dB
.194% = -54dB
.386% = -48dB
.967% = -40dB
1.5% = -36dB

Distortion @ 90dB/1M
.078% = -62dB
.029% = -71dB
.062% = -64dB
.110% = -59dB
.049% = -66dB



Sure, but we're talking similar distortion numbers at ten times the acoustic power.



Size, cost, and market inertia/prejudices.

The wave guide needs to be large compared to the frequencies involved. Put a nice round-over on the edge of a 15" wave guide cabinet and you end up with a big cabinet - Earl's Summa is 24" wide. The Abbey is a more svelte 15" with small round over . Where the high end market wants a foot-wide speaker and spouses want something jewelry box sized that's not good.

We didn't understand diffraction as well when we needed horns to mate to low powered tube amplifiers, so many had a characteristic sound which isn't there with more modern profiles (like oblate spheroids) and no compression chamber (where the throat is smaller than the compression driver and a chamber is used between them).

Wave guides are getting popular with domes. Revel uses them on its Ultima 2 Salon tweeter. Genelec uses them on its powered monitors.

The driving impetus behind horns is often efficiency. 100W into a 108dB system would be as loud as 10,000W into a somewhat sensitive 88dB home system if the drivers didn't bottom and voice coils vaporize. Obviously you don't need that at home.

You do want uniform power response. Harman's double-blind testing involving acoustically transparent scrims and a computerized speaker mover reveals it's what listeners prefer regardless of experience, musical preferences, and country of origin.

The usual approach (B&W Nautilus, Revel Ultima Salon2, Vandersteen Model Five) is uniformly broad dispersion through the use of acoustically small drivers and baffles.

When you can park yourself and speakers in the middle of a large room with reflections 10ms out that works wonderfully; but most domestic environments have only 3-4ms of delay.

You need uniform limited dispersion to work around that; where the wave guides are good at both uniformity and off-axis attenuation.



For studio monitoring you can park yourself and speakers in the middle of an acoustically treated room. You don't need the size and expense.



Objective measurements and subjective listening impressions of modern wave guide systems do not bear that out.

Thanks for the info. I guess I was thinking, rightly or wrongly, of horns as distinct from waveguides. I have seen enough distortion plots of waveguide-equipped speakers that I'm not overly concerned about distortion introduced by good waveguides. Though BTW I remember seeing a claim from a speaker company that ANY waveguide introduces some distortion.

The Revel Studio2/Voice2 are actually on my list to consider. I did look a bit on the web at the JBL Synthesis systems, after people here mentioned it.
Comparing the JBL Atlas to the Studio2, the Atlas is 93dB sensitive with 300W powerhandling, yielding only 2dB more peak volume than the Studio2 (88.7dB, 500W). (How each would actually SOUND on peaks near those power extremes I don't know...I haven't auditioned even the Revel yet.) Yet the Atlas appears more designed for soffit mounting, whereas I want freestanding, and still lists $9k each (I think) vs $8k each for the Studio2. Going up to the K2 gets something more intended for freestanding use (plus more SPL), but the price apparently kicks up to $15k each (definitely beyond budget), and the unit doesn't even seem to take diffraction issues seriously. From what I understand, discounts would be harder to achieve on Synthesis as compared to Revel. And I'm not aware of any independent comprehensive measurements of the Synthesis series. I take manufacturer specs with a grain of salt.
syswei is offline  
post #153 of 173 Old 05-17-2009, 01:08 PM
AVS Special Member
 
MLKstudios's Avatar
 
Join Date: Jun 2007
Location: Hollywood, CA
Posts: 1,986
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
syswei,

If you are planning on using a screen in a dedicated theater, you might also want to consider JBL's Cinema speakers (the same used behind the screen of many movie theaters). They are not that expensive, but require a pro amp each to sound good.

If instead, you are looking for a combo music/HT living room design, I'd probably go with the Revels (or similar). It's a more traditional setup you could run with a Mac, Lexicon or Parasound.

What I like about my HT Synth speakers, is when watching a movie, I turn down the lights, and they disappear. It is truly a "Kinosound" experience. In contrast, the Revels would give you something to visually admire when listening to music.

My needs are 90/10 movies to music, but they sound great when I want to "rock out". It's as if "Ozzy is right there in the room singing just for me".
MLKstudios is offline  
post #154 of 173 Old 05-17-2009, 02:06 PM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Revel Studio2 (88.7dB, 500W) even though they are great sounding speakers are not even a top 5 choice and do not meet my requirements for HT. Again, that is just my requirements. Yours might be different.

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #155 of 173 Old 05-17-2009, 02:12 PM
AVS Special Member
 
MLKstudios's Avatar
 
Join Date: Jun 2007
Location: Hollywood, CA
Posts: 1,986
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
penn,

What are the "top five"?
MLKstudios is offline  
post #156 of 173 Old 05-17-2009, 03:36 PM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Quote:
Originally Posted by MLKstudios View Post

penn,

What are the "top five"?

In no particular order

Seaton catalysts
LTR triple 12s (or 8s)
Emerald Physics CS2
Line array (like the selah symetrica or even AV123 LS9)
My DIY designs (TD12S,PHL 1120, Neopro5i)

I do not consider Revel a HT speaker designer actually, just like I dont consider most manufactures HT designers. Most cater too much to the music crowd.

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #157 of 173 Old 05-17-2009, 03:45 PM
AVS Special Member
 
Drew Eckhardt's Avatar
 
Join Date: May 2001
Location: Sunnyvale, CA USA
Posts: 2,674
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by syswei View Post

The Revel Studio2/Voice2 are actually on my list to consider. I did look a bit on the web at the JBL Synthesis systems, after people here mentioned it.

You'll do better if you get away from conventional designs.

If space (2' wide and deep) and aesthetics (black) allow, the Gedlee Summa is 98dB efficient in full space or 104dB into half space. 1250 Watts power handling. F3 of 80Hz. $3K each.

The Abbey is 15" wide and Nathan 12" with lower efficiency from the smaller midranges and less directivity at lower frequencies due to the smaller wave guides.

Gedlee is a concatenation of (Earl) Geddes and (Lidia) Lee his wife. Earl has the PhD in acoustics and decades developing audio equipment. Dr Lee's background is in psycho-acoustics.

Duke Lejune sells similar speakers with better wood work under the Audio Kinesis brand but without Earl's proprietary open celled foam plug (difracted waves cross it repeatedly so they're more attenuated than the direct sound).

I'm especially enamored of Linkwitz' use of dipolar radiation which maintains directivity down to DC and own a pair of Orions although the wave guide designs can have an extra 20dB of headroom and appear to do a more uniform job dealing with off-axis radiation. I'd like to see how a wave guide up top mates to a dipole at low frequencies which is what Emerald physics does.

Seaton Sound and LTR make interesting use of coaxials in high efficiency designs. Coaxials do a wonderful job with polar and power response. So you want to look at the Danley Sound Labs unity/synergy horns which feed one wave guide with a compression driver at its apex and lower frequency drivers along its depth.
Drew Eckhardt is offline  
post #158 of 173 Old 05-17-2009, 03:47 PM
AVS Special Member
 
NIN74's Avatar
 
Join Date: May 2001
Location: Skoghall, va, Sweden
Posts: 3,570
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 13
Quote:
Originally Posted by penngray View Post

Revel Studio2 (88.7dB, 500W) even though they are great sounding speakers are not even a top 5 choice and do not meet my requirements for HT. Again, that is just my requirements. Yours might be different.


Revel makes good speakers, but they will probably have some problem at high SPL.

Sound and video is not magic, it is pure physics. Physics that can be magical
NIN74 is offline  
post #159 of 173 Old 05-17-2009, 03:55 PM
AVS Special Member
 
MLKstudios's Avatar
 
Join Date: Jun 2007
Location: Hollywood, CA
Posts: 1,986
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
penn,

While the Catalyst and T-12's are more than capable speakers, they won't match everyone's "décor". Not sure how many would like AV123 LS9's either (looks not sound). The Emerald Physics CS2 are some very cool looking speakers (I had to look them up). Wouldn't mind glimpsing at those will listening to music.

You have to add the Synthesis line for HT. They will best most any speaker in clarity and SPL ability.
MLKstudios is offline  
post #160 of 173 Old 05-17-2009, 04:26 PM
AVS Special Member
 
4DHD's Avatar
 
Join Date: Aug 2004
Location: sierra ecuadoriana
Posts: 5,811
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 62
JBL Arrays!
The protoypes, belonging to Greg Timbers, JBL Eng.

The Array 1400
4DHD is offline  
post #161 of 173 Old 05-17-2009, 04:53 PM
AVS Addicted Member
 
MKtheater's Avatar
 
Join Date: Jul 2006
Location: New Hartford, NY
Posts: 14,376
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 167 Post(s)
Liked: 421
Penn, you can add this to your options, loud and clear and if you want can reach 133 db's in room for $4250(all of it). You probably don't want this in a family room though, takes up a whole wall.

MKtheater is online now  
post #162 of 173 Old 05-17-2009, 06:59 PM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Well yeah....and those I was trying to not scare everyone, the "pro audio" stuff scares people Im still jealous of your room every time I see your picture.



and the JBL everest DD66000 for about $22K

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #163 of 173 Old 05-17-2009, 07:01 PM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Quote:
Originally Posted by MLKstudios View Post

penn,

While the Catalyst and T-12's are more than capable speakers, they won't match everyone's "décor". Not sure how many would like AV123 LS9's either (looks not sound). The Emerald Physics CS2 are some very cool looking speakers (I had to look them up). Wouldn't mind glimpsing at those will listening to music.

You have to add the Synthesis line for HT. They will best most any speaker in clarity and SPL ability.

I agree...but this discussion kind of move into the custom high SPL for custom HT room opinions Atleast that was my assumptions.

Two nice speakers in the family room discussion is in another thread.

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #164 of 173 Old 05-17-2009, 08:56 PM
AVS Special Member
 
4DHD's Avatar
 
Join Date: Aug 2004
Location: sierra ecuadoriana
Posts: 5,811
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 62
Quote:
Originally Posted by penngray View Post

Well yeah....and those I was trying to not scare everyone, the "pro audio" stuff scares people Im still jealous of your room every time I see your picture.



and the JBL everest DD66000 for about $22K

$22K would be a bargain for the Everest, its $30K/ea.
The new K2 9900 is $22K,


4DHD is offline  
post #165 of 173 Old 05-17-2009, 09:01 PM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
I saw the $22K somewhere online.

I now really wanting to copy those horn designs!! I have lots of 12" drivers ready to be used!

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #166 of 173 Old 05-17-2009, 09:21 PM
AVS Special Member
 
MLKstudios's Avatar
 
Join Date: Jun 2007
Location: Hollywood, CA
Posts: 1,986
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
There is some info on the Everest at the Lansing Heritage forum by Timbers.

The two 15" woofers are not crossed over the same....

"The 1501AL 380mm (15") woofer utilizes an Aquaplas-treated-pulp cone that preserves sonic neutrality while damping
internal resonances and providing controlled and articulate bass response. The crossover network is designed to allow
the woofers to operate in different frequency ranges, a configuration that provides optimum directivity and high output.
The crossover network employs a DC-battery bias system that keeps the capacitors operating in Class A mode, yielding
maximum sonic purity."
MLKstudios is offline  
post #167 of 173 Old 05-18-2009, 05:02 AM
AVS Special Member
 
J_Palmer_Cass's Avatar
 
Join Date: May 2005
Posts: 6,396
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 224 Post(s)
Liked: 96
Quote:
Originally Posted by ack_bk View Post

Okay, I spent some time with the SPL meter and a Blu-Ray movie "We Are Marshall" and will gladly share my thoughts on what I experienced. First off, the equipment and room:


Selected the "True-HD" track for testing purposes. My SPL meter is a digital Radio Shack model, and all tests were done on the center of the couch (my normal listening position) at ear level). Here are the results:



Did you measure average SPL, or peak spl? The Digital RS SPL meter can measure both.

You have to set the MAX function to ON and use the function that stores the peak readings. The peak readings are to fast to be seen by eye, so the store function must be used.

Playback of an action movie with average readings around 100 dB C SPL scale sounds quite loud, but the same scene played back with peak readings around 100 dB C SPL scale does not sound very loud.
J_Palmer_Cass is offline  
post #168 of 173 Old 05-18-2009, 05:06 AM
AVS Special Member
 
J_Palmer_Cass's Avatar
 
Join Date: May 2005
Posts: 6,396
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 224 Post(s)
Liked: 96
Quote:
Originally Posted by whoaru99 View Post

I don't care what volume anyone listens at. That's their problem.

My only point was I don't believe it matters from a hearing damage perspective whether or not the 100dB (or what ever) sounds good or sounds like crap. It's still 100dB.




One man's 100 dB may not be another man's 100 dB!

SPL readings meaning 100 dB average or 100 dB peak?

SPL meter's use of the SPL "A" scale or the SPL "C" scale?

SPL meter's use of the fast response or the slow response?



The OSHA limits are based on time with constant SPL measured with the SPL A scale used with slow response. HT peak measurements are based on PEAKS with the SPL C scale used with fast response. I am not sure if you can measure PEAKS with an RS AMALOG SPL meter. The RS DIGITAL SPL meter can store the PEAK readings. A 100 dB reading for all readings does not mean the same thing.


http://www.osha.gov/pls/oshaweb/owad...RDS&p_id=10625



.
J_Palmer_Cass is offline  
post #169 of 173 Old 05-18-2009, 05:46 AM
AVS Addicted Member
 
penngray's Avatar
 
Join Date: Feb 2006
Location: Florida
Posts: 26,779
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Quote:


The crossover network employs a DC-battery bias system

4DHD has talked aobut that Bias crossover stuff and I have read about it on DIYaudio (I think).

It is not "open-minded" to reject knowledge - Bob Lee
penngray is offline  
post #170 of 173 Old 05-18-2009, 08:20 AM
AVS Special Member
 
4DHD's Avatar
 
Join Date: Aug 2004
Location: sierra ecuadoriana
Posts: 5,811
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 62
Quote:
Originally Posted by penngray View Post

4DHD has talked aobut that Bias crossover stuff and I have read about it on DIYaudio (I think).

Yep, I built C-C networks for some, then, 25 year old speakers and its a difference of night/day. It also helps that all the caps I used were poly caps. Far better than what was used 30 years ago. Plus having new tweeters and the woofers re-built.

Quote:
I saw the $22K somewhere online.

I now really wanting to copy those horn designs!! I have lots of 12" drivers ready to be used!

Like I mentioned, the K2 s9900 just came out 2 months ago with a price tag of $22500 each. And JBL has already taken orders totalling $1M.
4DHD is offline  
post #171 of 173 Old 05-18-2009, 12:10 PM
AVS Special Member
 
Raymond Leggs's Avatar
 
Join Date: Jul 2006
Posts: 3,612
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by MKtheater View Post

Penn, you can add this to your options, loud and clear and if you want can reach 133 db's in room for $4250(all of it). You probably don't want this in a family room though, takes up a whole wall.


I'm afraid of that thing!

One shall stand... One Shall Fall... - Optimus Prime
Raymond Leggs is offline  
post #172 of 173 Old 05-18-2009, 12:15 PM
AVS Addicted Member
 
MKtheater's Avatar
 
Join Date: Jul 2006
Location: New Hartford, NY
Posts: 14,376
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 167 Post(s)
Liked: 421
The best part is that no one sees it when they come in, it is all behind the screenwall.
MKtheater is online now  
post #173 of 173 Old 05-18-2009, 07:15 PM
AVS Special Member
 
whoaru99's Avatar
 
Join Date: Dec 2004
Posts: 6,960
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 67
Quote:
Originally Posted by J_Palmer_Cass View Post

One man's 100 dB may not be another man's 100 dB!

SPL readings meaning 100 dB average or 100 dB peak?

SPL meter's use of the SPL "A" scale or the SPL "C" scale?

SPL meter's use of the fast response or the slow response?



The OSHA limits are based on time with constant SPL measured with the SPL A scale used with slow response. HT peak measurements are based on PEAKS with the SPL C scale used with fast response. I am not sure if you can measure PEAKS with an RS AMALOG SPL meter. The RS DIGITAL SPL meter can store the PEAK readings. A 100 dB reading for all readings does not mean the same thing.


http://www.osha.gov/pls/oshaweb/owad...RDS&p_id=10625



.

I assume when making such statements they're apples-to-apples.

Probably a mistake, although it shouldn't be.

Just because there is a knob doesn't mean you should turn it.
whoaru99 is offline  
Reply Speakers

User Tag List

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