List of Reference Level, High Sensitivity & SPL Speakers - Page 9 - AVS Forum
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post #241 of 824 Old 02-18-2012, 08:34 PM
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[quote=Eyleron;21666118]OK, it's another issue. I'll need to read more to understand this.

It sure would help if the articles and calculators actually mentioned decibels, db, or spl. It appears they're talking about ohms law and how those variables relate in the amp, but not how it relates to spl output.

Thanks again for the info, and thanks for your patience![/QUOTE

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post #242 of 824 Old 02-19-2012, 09:02 AM
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Quote:


It sure would help if the articles and calculators actually mentioned decibels, db, or spl.

I found a thread here on AVS that explains it in really well terms of SPL, and it pointed out a mistake in my previous post:

http://www.avsforum.com/avs-vb/showthread.php?t=1236682

Quote:


Assuming all other things are equal-the 4 ohm cannot take twice the power. It will produce a louder SPL for the same given input voltage-but the max output will be the same.

Let's say a 8 ohm loudspeaker will produce 100dB with a 2.83V input signal. Then the 4 ohm would produce 103dB with the same input voltage.

The 8 ohm would be pulling 1 watt and the 4 ohm would be pulling 2 watts.

But if the power handling is 100 watts, then the max SPL would be 120dB in either case.

So when I said this:

Quote:
Originally Posted by nizl View Post

you need DOUBLE the wattage for a 4 ohm speaker, vs an 8 ohm speaker, to achieve the SAME loudness.

That is wrong, sorry! That's probably what was confusing you. You need double the watts for the same voltage, but the SPL will still be higher.

To resolve the confusion, here's what I would do to normalize for SPL:

1) Penalize the 4 ohm speakers -3dB in sensitivity (since they're double-counting watts)
2) Keep the ranking showing that a 800w speaker is better than a 400w speaker, regardless of impedance

I think this is what you were saying:

Quote:
Originally Posted by Eyleron View Post

In other words, given two speakers, same sensitivity after normalizing for 8ohm, one rated at 4 nominal ohms, the other 8 nominal ohms, both rated for 400w, tell me how to use the ohms, volts, or amps in the SPL calculations to come up with a different result for the SPL output

So yes, if you take that approach, you will be able to use the SPL calculator to accurately calculate SPL.

This jives my experience, where you need to power a 4 ohm speaker with a beefier amp, but it will get louder in the end. But if a person buys a JBL 4722N and tries to power it with their Yamaha/Denon/Onkyo receiver, they would likely be disappointed with the results.
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post #243 of 824 Old 02-19-2012, 09:24 AM - Thread Starter
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Wow I appreciate you following up on that! You saved my mind and the time I was going to spend working through some speaker cases and making sure people were happy with TWO adjustments made to the four ohm speakers.

It's all coming together now, BUME!

Next I need to check all the four ohm specs to see how they rated sensitivity, as some might have given an 8 ohm equivalent rating.

What should I do with a 4 ohm speaker that's rated with 1 watt?

Thanks again!
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post #244 of 824 Old 02-19-2012, 10:24 AM
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Quote:
Originally Posted by Eyleron View Post

Added the MK S-150 and the MK LCR-750.

What is the sensitivity of the MK S-150? They do not list this on their site, or in the spec sheet that I have.

Quote:
Originally Posted by Eyleron View Post

Removed < 105dB
With a heavy heart, I've hidden those speakers that cannot produce 105dB with their peak watt rating. It gets to be too confusing, I suspect, to have a list with a stated purpose, and then also see a smattering of other speakers that either almost made it, or are there to illustrate how much they don't make the grade.

Note that other speakers like the KRK Expose, and Procella P6 also fell off. As I learn more about how to interpret their active amps this might change, as they're only 1.4dB short!

I'm open to suggestions about this.

Surprised you cut the Procella P6. (this is passive by the way) This speaker is 90dB sensitivity, and capable of 110 dB continuous, and 116 dB peak freestanding, and 116 dB continuous and 122 dB peak in baffle wall.

Procella specs
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post #245 of 824 Old 02-19-2012, 11:34 AM
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Quote:
Originally Posted by Eyleron View Post

Next I need to check all the four ohm specs to see how they rated sensitivity, as some might have given an 8 ohm equivalent rating.

What should I do with a 4 ohm speaker that's rated with 1 watt?!

If a speaker (regardless of ohm) is measured as 1w / 1m, then no adjustment is necessary. It's only for 4 ohm speakers that measure as 2.83V (most of them) that you need to normalize -3dB.

Separately, I agree with Digs that 105dB may be a bit harsh of a cutoff. Having "almost made it" speakers actually helps add context vs ppl wondering whether they were even evaluated or not.
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post #246 of 824 Old 02-19-2012, 04:08 PM - Thread Starter
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Quote:
Originally Posted by nizl View Post


If a speaker (regardless of ohm) is measured as 1w / 1m, then no adjustment is necessary. It's only for 4 ohm speakers that measure as 2.83V (most of them) that you need to normalize -3dB.

Separately, I agree with Digs that 105dB may be a bit harsh of a cutoff. Having "almost made it" speakers actually helps add context vs ppl wondering whether they were even evaluated or not.

Thanks.

Yeah, I struggle with the realistic utility of "near-reference," the contextual educational aspect of the lower-output speakers, and the semantics of "will it do reference level or not" of the list. Not to mention my arbitrary distance of 12 feet. The latter issue will be mitigated when the list gets more dynamic by allowing distance to be a user-controlled variable.

Okay...how about 100dB?
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post #247 of 824 Old 02-19-2012, 05:49 PM - Thread Starter
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Quote:
Originally Posted by DigsMovies View Post

What is the sensitivity of the MK S-150? They do not list this on their site, or in the spec sheet that I have.

http://www.mksoundsystem.com/home-pr...ies/s-150mkii/ click on the "Click for Specs" link with the red led light in the upper-right of the page (bad website design). It's listed as 91, not qualified as in-room or anechoic, so I dropped it 3dB to 88dB. Sometimes if the manufacturer gives the max output in room, I can extrapolate how the sensitivity was calculated. In this case, they don't give much info, so I can't. However, if you can point me to other test data, reviews etc. where the sensitivity is shown to be different, I'd be happy to correct this.

Quote:
Originally Posted by DigsMovies View Post

Surprised you cut the Procella P6. (this is passive by the way) This speaker is 90dB sensitivity, and capable of 110 dB continuous, and 116 dB peak freestanding, and 116 dB continuous and 122 dB peak in baffle wall.

Procella specs

The Procella P6 @ 12 feet using its stated 300 peak watts would hit 103.5dB. It's one dB short!

While its 70Hz frequency extension suggests that they were going for more sensitivity, the 6.5" woofer and the soft dome tweeter are holding it back, I suspect. And maybe the 4.5" depth?

Still sounds like a great speaker, from the reviews and its use by professional installers / designers, and the fact that since most people will be perfectly happy at -5dBfs and it works fine there, even back to 18 feet. Or, in a more typical room with less absorption, it'll hit 105-106dB, so it does work fine there too.

My criteria has gone from:
  • Speakers people consider for high output, along with some other speakers for comparison (so, anything goes?).
  • To only those speakers that can output 105dB using their stated peak watts and sensitivity.
  • To what I'm considering now: relaxing it to 100dB.

100dB peaks would at least allow for "near-reference-level" and as nizl said it'd provide some educational illustration. I liked having the even weaker speakers on there, because it's striking to see many popular 86dB speakers that would need 1,000 watts to hit 105dB, when their peak power handling is like 200 watts!
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post #248 of 824 Old 02-19-2012, 05:59 PM
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Quote:
Originally Posted by Eyleron View Post

While its 70Hz frequency extension suggests that they were going for more sensitivity, the 6.5" woofer and the soft dome tweeter are holding it back, I suspect. And maybe the 4.5" depth?

????????

The Procella P-6 uses 1" compression driver in a waveguide.....

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post #249 of 824 Old 02-19-2012, 08:51 PM - Thread Starter
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Quote:
Originally Posted by doublewing11 View Post


????????

The Procella P-6 uses 1" compression driver in a waveguide.....

Ok, I see how the description on the page does say compression driver. I was reading the spec sheet which made it seem like a regular tweeter. I see now the depth dimension is different on the page versus the spec sheet.
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post #250 of 824 Old 02-20-2012, 01:50 PM - Thread Starter
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100dB Cutoff
Okay, I copied back the 100dB @ 12 feet speakers from the "naughty list." Procella P6 is back.

4ohm Sensitivity
Earlier I dropped the 4ohm speakers' sensitivity 3dB. Today I went through each and fixed those that actually DID quote it at 1w, which doesn't need correction. Big kudos to those models that have it listed as 1w instead of 2.83v. Big kudos to those that list in-room or anechoic. Biggest kudos that list both (rare).

Cleanup
I also fixed some mistakes with JBL Pro Cinema speakers.

I've adjusted the max power handling on some JBL and Triad speakers and a couple others. When a speaker gave its max power handling as, say, 600w, I had previously used that as the peak. But since then I've realized that the 600w is with 6dB crest factor pink noise, which suggests that the peak handling is at least double that.
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post #251 of 824 Old 02-20-2012, 05:39 PM
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Quote:
Originally Posted by Eyleron View Post

100dB Cutoff
Okay, I copied back the 100dB @ 12 feet speakers from the "naughty list." Procella P6 is back.

4ohm Sensitivity
Earlier I dropped the 4ohm speakers' sensitivity 3dB. Today I went through each and fixed those that actually DID quote it at 1w, which doesn't need correction. Big kudos to those models that have it listed as 1w instead of 2.83v. Big kudos to those that list in-room or anechoic. Biggest kudos that list both (rare).

Cleanup
I also fixed some mistakes with JBL Pro Cinema speakers.

I've adjusted the max power handling on some JBL and Triad speakers and a couple others. When a speaker gave its max power handling as, say, 600w, I had previously used that as the peak. But since then I've realized that the 600w is with 6dB crest factor pink noise, which suggests that the peak handling is at least double that.

Yes, the JBL speakers I had can play really loud, more than I can handle which is why they sound so good for reference levels. They also use very good to great drivers. The surprise to me was the BFM stuff with the cheap drivers which tells me the design is excellent. They need major EQ though since mine do not use crossovers. Most people think these loud speakers to sound good but they are just not experienced with the good stuff. I would take SHO-10's over Maggies any day.
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post #252 of 824 Old 02-22-2012, 09:00 AM
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This thread/spreadsheet is Great. Couple potential HT speaker additions that I had been looking at before finding Klipsch KPs. BIC America FH6 LCR may be near 105 db at 12 ft (they claim 116 dB in specs) and for the price are well worth a glance and the GoldenEar Triton Twos have been attracting a lot of attention for their performance/price, but I can't find any peak dB ratings (and they have relatively low sensitivity)
Thanks for all the time and effort that has been put into this.
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post #253 of 824 Old 02-22-2012, 03:15 PM - Thread Starter
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Quote:
Originally Posted by billyum View Post

This thread/spreadsheet is Great. Couple potential HT speaker additions that I had been looking at before finding Klipsch KPs. BIC America FH6 LCR may be near 105 db at 12 ft (they claim 116 dB in specs) and for the price are well worth a glance and the GoldenEar Triton Twos have been attracting a lot of attention for their performance/price, but I can't find any peak dB ratings (and they have relatively low sensitivity)
Thanks for all the time and effort that has been put into this.

I have added the BIC FH6. Hard to get the numbers to add up with their claim of 116dB and the power handling, but it's a guesstimate extrapolation for now.
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post #254 of 824 Old 02-22-2012, 03:16 PM - Thread Starter
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I made a graphic showing the relationship between watts and dB for reference level for four example speakers.


Color in “Meter Graphs” and Text
Red indicate watt levels outside the speaker’s stated capabilities. Green indicates it’s within. Light green, to yellow, indicate threshold areas, such as where compression might begin for average levels, and where magnetic / physical limits might occur for peak levels.

The wide range of the yellow-ish gradient for average watts also indicates the range where compression begins, up to program power handling of 2x continuous.

The narrow range of the yellow-ish gradient for peak watts indicate the potential sudden onset of magnetic and physical limits (spider resistance, bottoming the driver).

Thermal Compression in Average-to-Program Watts
Thermal compression starts at one-tenth to one-eighth continuous 6dB crest factor pink noise power rating, which is less stressful than 3dB crest factor sine waves. As the voice coil heats up from high average levels, the resistance changes, which causes a decrease in output (compression) and distortion.

Magnetic & Physical Compression
At high peak levels, the magnetic flux changes will cause distortions in the sound. Excursion leaving the magnetic gap will cause distortion and loss of output. The spider’s resistance will be non-linear and impart distortion.
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post #255 of 824 Old 02-26-2012, 03:29 PM
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I am interested in how the JBL Project Array 1400 stacks up in this analysis (since I own them). It has 89 dB sensitivity, 300 watts "recommended amplifier power". Price used $3500, new $5,750. I ran the calcs but I'm not sure whether the 300 W rating is "Program" or "Peak". If I assume 300 W is Program, and guess that Peak is 600 W, then I get 105.6 dB Peak.


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post #256 of 824 Old 02-27-2012, 06:37 PM - Thread Starter
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Quote:
Originally Posted by LeBon View Post

I am interested in how the JBL Project Array 1400 stacks up in this analysis (since I own them). It has 89 dB sensitivity, 300 watts "recommended amplifier power". Price used $3500, new $5,750. I ran the calcs but I'm not sure whether the 300 W rating is "Program" or "Peak". If I assume 300 W is Program, and guess that Peak is 600 W, then I get 105.6 dB Peak.

I have added the 1400, as a couple other K2 speakers, the 5800 and 9800.
These look like fantastic speakers!
It's interesting to read that the vertical horn removed from enclosure was disliked by Japanese consumers, hence some differences between the K2 and the Project Array series.

I have been surprised by JBL's consumer line, as I've expected higher sensitivity. The marketing hyperbole certainly leads one to expect pretty high output!

It's disappointing that JBL doesn't provide much specification disclosure. What's the peak power handling, tested how? Distortion? Sensitivity is anechoic or in-room? This is not criticism of the 1400, but rather all of JBL's consumer line's marketing. If I was proud of my company's engineering and research departments, I'd tout that by providing MORE information than my competitors. "This is how this speaker performs, honestly." Which is more how their pro line behaves.

While the K2 feature 92-94dB sensitivity, the 1400 as you said is 89dB.
105.6 dB at 12 feet, using 600w peak power, or 533w to reach 105dB.

Can you or others verify that the sensitivity is 89dB anechoic? It seems like a crazy question, since that already seems too low for large drivers and a horn compression driver, but who knows? This and many other JBL speakers are an enigma to me.

What are the design trade-offs? Way lower distortion than smaller speakers with 10" woofers with more sensitivity? Are the extra crossover components of the 3-way design eating into efficiency?
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post #257 of 824 Old 02-27-2012, 09:16 PM
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Quote:
Originally Posted by Eyleron View Post

What are the design trade-offs? Way lower distortion than smaller speakers with 10" woofers with more sensitivity? Are the extra crossover components of the 3-way design eating into efficiency?

I recall reading somewhere that the sensitivity of the horns was dialed back to better blend with the 14" woofer. I'll see if I can find any more detail on the specs. Here's a link to the technical data over on the Lansing Heritage site - http://www.audioheritage.org/vbullet...643-1400-Array


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post #258 of 824 Old 02-28-2012, 08:45 AM
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Here is a link to JBL's note on power requirements.
http://www.lansingheritage.org/html/.../power-req.htm


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post #259 of 824 Old 02-28-2012, 05:31 PM - Thread Starter
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Quote:
Originally Posted by LeBon View Post

Here is a link to JBL's note on power requirements.
http://www.lansingheritage.org/html/.../power-req.htm

Interesting, thanks! It clarifies for me why peak power is 4x the RMS value: because it's tested with a 6dB crest factor signal.

So JBL is stating, at least then, that it rated the speaker for 8 hours of use. Presumably, after 8 hours, bad things happened.

It was also fun to browse "up" the levels and read some other tech notes. Bookmarked.
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post #260 of 824 Old 02-28-2012, 07:07 PM
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I started a thread on this question over on Lansing Heritage. The first reply was:
"The sensitivity of the horn combo is 98 dB (http://www.jblsynthesis.com/Products/Details/103), but it is padded WAY down to match the sensitivity of the woofer. There must be some big a** resistors in that crossover, because most (7/8ths?) of the mid and HF power is being turned into heat by the crossover. You would need 8 woofers per speaker to get the system back up to 98 dB, which is a little impractical. The WAF on these things is already pretty low. "

Here's a link to my thread: http://www.audioheritage.org/vbullet...-on-Array-1400


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post #261 of 824 Old 02-28-2012, 08:17 PM - Thread Starter
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I guess it's simply a design catering to two channel fans. Or people mistakenly thinking (IMO) they'll get better bass without a sub, or with a 40 Hz crossover? Do focus groups say, "More output? Meh, it looks big already. Give me extension cuz I likes me some bass!"

What's this LE14H-4 model?

Do you think the sensitivity of the K2 models is another Japanese preference?
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post #262 of 824 Old 02-29-2012, 08:52 AM
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Quote:
Originally Posted by Eyleron View Post

I guess it's simply a design catering to two channel fans. Or people mistakenly thinking (IMO) they'll get better bass without a sub, or with a 40 Hz crossover? Do focus groups say, "More output? Meh, it looks big already. Give me extension cuz I likes me some bass!"

What's this LE14H-4 model?

Do you think the sensitivity of the K2 models is another Japanese preference?

I think it's a design catering to fans of balanced sound from the speaker. There is a companion subwoofer (Array 1500) with a 15 in. driver and a 1000 W amp, which I am using in my configuration.

The LE14H-3 is used in the Array 1400. JBL is using the LE14H-4 model in the S4600 speaker system.

I think the sensitivity of the JBL high end models is dictated by the woofers they use. The horns used for the high end are clearly much more efficient. Sensitivity is only one factor in speaker design, and I would argue that the Project Array series can deliver reference levels in a home theater setting.


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post #263 of 824 Old 02-29-2012, 09:52 AM
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I'd agree,...ease of achieving a nice balanced sound. The 1400 gives you ruler flat spectrally averaged response, a significant degree of directivity control and uniformity. These two traits are highly sought after wrt Toole's (et al) findings. Smooth response, smooth off axis energy,..the LF driver blends ideally into the 3" compression mid, that's why the big driver is needed up to the transition, to maintain the coverage mating to the MF horn, "ala beaming" to some degree.

WRT JBL's modest sensitivity ratings,..I believe honest may be a better adjective. They're more forthright wrt their specs than about anyone. Then again they're responsible for a huge amount of all driver/loudspeaker/psychoacoustics R&D. Yes, when considering total design sensitivity with these, everything is dependent on the LF driver, hence the MF/HF padding. In this case, the LF driver is needed to cover all the way too the end of the musical range, solid to 25hz in room. If this were a limited LF design, like Seaton's Cats, Greg Timbers could've designed the 1400 with a pro LF drive, thus upping the sensitivity number significantly. All about design choices/comprimise.

I've heard the 1400, however not in ideal situation, so I'll not comment. However, it's a very highly regarded design, and in use it achieves great reviews.


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post #264 of 824 Old 02-29-2012, 10:58 AM
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Just a little house-keeping;

Quote:


Magnetic Compression
More typically in bass drivers, at high levels, stuff happens to the magnetic flux fields that make the power response nonlinear.

Also, the woofer can be driven so hard that it's out of the linear portion of the magnetic gap, and the field weakens.

I still don't know if that typically happens if you stay within the speaker's max peak power rating.

From the compression thread, I submitted;

Quote:


This is an aspect that rarely gets discussed, however power compression isn't only due to the thermal aspects of the heating of the voice coil. Yes, the majority of compression as we know it results from the ability of the voice coil to dissipate heat, but another component to compression is magnetic flux compression. Although the typical thermal compression most discussed is more long term, the effects of magnetic compression are instantaneous. These magnetic compression distortions, can dull transients, and render reproduction as lifeless, dull and unrealistic.

Certainly, thermal compression is a big issue. The vast majority of mfrs. have no idea of their products compression characteristics, other than their likely not so good. This is why typical residential speakers are inadequate for the huge dynamic swings associated with realistic HT. Many enthusiasts merely discount the effects of compression, because they are mostly subtractive in nature. But subtractive they are, compression robs the playback of life/realism. These effects are insidious because it's not an offensive distortion. It just thins out the presentation,...no life or snap. Oftentimes, without a direct comparison, the un-initiated have no idea of what they're missing.

The magnetic issue lies in the fact that when the drummer hits the kick drum pedal, and the beater strikes the head, the signal path results in the voltage is impressed across the loudspeaker's terminals. This results in the current flow in the VC, and subsequently the driver attempts to track the signal accurately. The problem is that when current flow begins in the VC, there exists three separate, and entirely different sources of magnetic flux in the gap. The permanent magnet's flux, the signal voltage VC flux, and lastly the flux that's generated by the varying eddy currents in the pole pieces. This is the problem, the flux modulation compression.

Whereby the thermal compression effects are a function of time, the magnetic flux compression is instantaneous. Magnetic saturation of any of the motor elements needs to be entirely avoided, as it's effects instantly impact waveform shape, the peak, and peak capability.

So just as reducing drive levels to avoid thermal buildup and subsequent losses, avoiding magnetic compression should be a goal to be mindful of even if it's only for the split second of the top of any given waveform. Depending on the frequency, we can reduce drive levels via spreading the signal over multiple drive units, ie multiple subwoofers, mid-bass units etc. Fortunately this flux modulation compression is most prevalent with high current levels that are typically associated with low frequencies,...thus enabling implementing multiple drivers covering the given passband without acoustic interaction issues that would accompany multiple drivers at higher frequencies.

I've experimented with the effects of compression, and be it thermal or magnetic, and spreading the drive signal across multiple drive units, thereby reducing the effects of potential compression, can be quite dramatic.

I just wanted to take a moment to clear this ambiguity up. It's not anything to do with driving the VC out of the linear component of the gap. It's the complex effect whereby the quickly changing* magnetizing force of the high currents through the voice coil, interacting with the permanent magnet magnetic field of the driver, then throw in the non-linearity element of the magnetic field set up by the ever changing eddy currents in the pole pieces.

(*Say for example a 41.2 hz E string on a bass guitar, and for simplicity we'll forget about the large amount of all it's harmonics. Remember, there exists two magnetic reversals per cycle.)

So the initial magnetic field is established, hypothetically, in a couple cycles the magnetic field attains full strength. Magnetically, all is relatively linear as long as the peak stays within the capability of the materials, or stays low enough to avoid the effects of saturation. Saturation is the condition attained when the increase in the applied magnetic field, doesn't increase the magnetization of the material further. Thereby the rapidly rising effect is dampened somewhat, and the rise is leveled off to a degree.

This is the compression, the magnetic compression, that I was referring to.

Clearly, driver mfrs can make the magnetic motors that are robust and avoid some of the non-linearities associated with compression,...thermal or magnetic. Enthusiasts can spread the high drive signals across multiple drivers, mitigating much of the negative effects. Keeping the drivers as centered as possible in the magnetic gap further reduces the associated effects of the non-linear Bl curve, and the third interactive magnetic effect.

The cool thing is that this flux modulation compression typically only comes with the higher currents that accompany the lower frequencies. So as long as it doesn't present negative acoustic interactions, multiple drivers/magnetic motors covering any given passband is helps in a multitude of ways, thereby rendering the effects of any potential compression of little consequence.


I know, what a yawner I'm just sayin',
... but all said, once again, headroom is the answer


Eyleron, quite an undertaking, you're to be commended. Great job.

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Flat, Deep, Clean, Linear, and Loud
------------------------------------
Active 16.8kw, 7.3 system
(3)Seaton Cat12C up front, (4)QSC K8 sides/rears
(2)Seaton SubM-HP, (4)18" IB
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post #265 of 824 Old 03-22-2012, 08:52 AM
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How about the Aerial Acoustics 7T's? They have an 89db efficiency rating but can apparently handle 600 watts.

The CC5 can handle 700 with only an 86db sensitivity rating
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post #266 of 824 Old 03-22-2012, 05:54 PM - Thread Starter
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How about the Aerial Acoustics 7T's? They have an 89db efficiency rating but can apparently handle 600 watts.

The CC5 can handle 700 with only an 86db sensitivity rating

Thanks for the suggestion!
The Aerial Acoustics 7T is a newer three-way tower speaker with two woofers, a midrange, and a tweeter. The cabinet is well designed with curved sides and very well braced, and it employs custom drivers. This is a full range speaker that extends to around 27Hz.

I've added this speaker to the list, but it's in that marginal zone.

Power Handling: Can someone verify this? I see in the Aerial Acoustics 7T thread that people mention various amplifiers, but it'd be nice to read in a review, or manufacturer's comment what RMS, program, or peak power handling is. I guessed at 400 program / 800 peak based on what people were saying in threads.

Sensitivity: The manufacturer lists this as 89dB, but Stereophile's review lists it as 86.6dB.
I used the reviewed / tested sensitivity, like I did the Klipsch Reference.

To normalize for 8ohm for fair comparison, the sensitivity needs to be dropped another 3dB (they list for 2.83v, instead of 1 watt), so it becomes 83.6.

Peak Output: @ 12 feet, anechoic, with an assumed 800w peak amplification, it's 101.4dB. This puts it in the gray area above 100dB but under 105dB.

Regardless of power handling, it'd take 1,847 watts to reach 105dB from 12 feet. This is an audiophile speaker for refined listening, and it looks like it trades extension for efficiency.
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post #267 of 824 Old 03-23-2012, 03:36 PM
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Thanks for taking on this 1000 lbs "gorilla"! There is no way you can make everyone happy.......

On that note, I'm perplexed why you have deducted 3 db's of sensitivity for the Triad Gold LCR and the Triad Platinums? Not to mention not listing the Gold Monitors with their 92.5 db/watt/meter sensitivity rating.

Triad clearly states X db's/1 watt/ meter for their 4 ohm speakers. Crossovers values and suggestions have been clearly chosen by Triad to increase sensitivity and to be supplemented by a bass system.

I can attest fore-mentioned products will hit reference levels 12 ft from listening position as I was privy to such measurements in a dedicated room! Seems to me, questionable information can be misleading consumers toward nebulous conclusions..........

Sorry........just my take.

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post #268 of 824 Old 03-23-2012, 04:51 PM - Thread Starter
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Thanks for taking on this 1000 lbs "gorilla"! There is no way you can make everyone happy.......

You're welcome. It has truly been quite the beast, but also a learning experience.

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On that note, I'm perplexed why you have deducted 3 db's of sensitivity for the Triad Gold LCR and the Triad Platinums? Not to mention not listing the Gold Monitors with their 92.5 db/watt/meter sensitivity rating.

Triad clearly states X db's/1 watt/ meter for their 4 ohm speakers.

I appreciate your advocating for the Triads and fact-checking. I can't do it all myself, and it's only through others' research and help that the list can grow and be better and of higher quality.

When I read this I was surprised. I expected to find a comment by me in the sensitivity field for the Triad ty about normalizing, or reading them reviewed lower. Alas, no comment. My bad.

I agree, to Triad's credit, they didn't play the game about stating sensitivity for a 4 ohm speaker at 2.83v like so many others do.

HomeTheatMag said that the Platinum measured with lower sensitivity. And Triad's own specs don't specify anechoic or in-room. Most of the time, if it's not qualified, it's in-room. Since all the sensitivities are given as anechoic, I probably dropped it.

That said, I'm not exactly sure how I came up with the numbers there.

I do feel a little bad, because for most of the speakers, I don't find reviews that disagree. In Triad's case, I think I was just googling for pricing or something and came across the review. I intentionally dropped Klipsch sensitivity 3dB across the entire Reference line because they were so notorious for being inflated.

As someone in the know about Triads, could you find me posts on AVS or some such where Paul addresses the sensitivity as being in-room or anechoic? Or competing reviews that agree with the stated specs?

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Seems to me, questionable information can be misleading consumers toward nebulous conclusions..........

Oh, it definitely does. If I got something wrong, my only consolation is that even professional magazines have to print retractions, and if you scan through this thread you'll see this wouldn't be the first time, and is nothing against Triad or any other brand.

And I feel like correcting some misconceptions and providing education about how difficult it can be to reach those higher levels and how speakers compare, in general, helps consumers by filling a void. Imagine never reading in car reviews how fast a car could accelerate or what its top speed was! (although I realize that I'm not testing speakers, but only presenting the speakers as a filtered list)
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post #269 of 824 Old 03-23-2012, 07:02 PM
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HomeTheatMag said that the Platinum measured with lower sensitivity. And Triad's own specs don't specify anechoic or in-room. Most of the time, if it's not qualified, it's in-room. Since all the sensitivities are given as anechoic, I probably dropped it.

My question to Home Theater Magazine...........what measuring device was used to surmise their conclusion on measured data set.........what element of variation and/or margin or error is inherent in their sample set of data............what form of accuracy and/or precision was utilized in preparation of their final analysis.............how large was their sample set?

Too many questions concerning Home Theater Magazines' published conclusions................though I suspect their analysis of measured data does fall with in +/- 1-2% reliability factor.........ie. Triads spec of 94.5 dbs/watt/meter is in fact.......... actually accurate.

Walking on a slippery slope relying on published magazine' data.......

Just my opinion...............

Quote:


As someone in the know about Triads, could you find me posts on AVS or some such where Paul addresses the sensitivity as being in-room or anechoic? Or competing reviews that agree with the stated specs?

Once again, walking a slippery slope...............only an independent 3rd party not associated with manufacturing or selling subscriptions/advertisements can be relied upon actually testing and drawing conclusions based upon empirical data of measurement.

Do you have your measuring tools at the ready?

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post #270 of 824 Old 03-23-2012, 08:12 PM - Thread Starter
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OK, let's stick with what Triad meant with their spec. Is it in-room, or anechoic?
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