Amen, and can I get a Halleluja?
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Speaker sensitivity
- Thread starter Thomas savage
- Start date
Amen, and can I get a Halleluja?
Maybe, but if the trend were to continue unabated all music could end up sounding like this.
Welcome to DR 00
I'm on the same page as you with pretty much everything, but I'll have to strongly disagree with you here.
I can understand artistic intent if the album is compressed in recording/mixing to get a desired sound. Compression in mastering is inexcusable particularly for jazz and classical and to a slightly lesser extent rock. Live music is all about dynamics and the nuances between soft to loud and vice versa. You blunt that when you add compression.
I will see if I can put up samples of a jazz recording that has a mastering of DR7/8 and one that is DR13+. The differences are significant regardless of the speakers. One of them can fool you into thinking you're listening to a live recording, the other sounds like a wall of sound when both are played at an equally matched active listening volume, matching with ReplayGain (I heard it on the highly sensitive K-402 demo I posted about). The only area I could excuse the DR7/8 mastering is if you're listening to it in the car where the road/engine noise is loud so you need all the instruments brought up to a more normalized level. That is where I have a hard time listening to hugely dynamic music like classical. And I don't have one of those sissy M3's that pumps fake engine noise through the speakers
Hi
It can be shown that a few keys jingling can produce instantaneous SPL peaks up to 120 dB @ 1m ... I learned this from a WBF post by the eminent Tom Danley of Danley Audio fame. Low sensitivity speakers even when driven by 1000 watts amplifers can't reproduce that kind of level ... for the sake of argument and since we're a Science forum a 85 dB speaker would need 2000 watt to reproduce that kind of level while a 105 dB would only need 100 watts! You can see where this is going.
If this is accepted I could reproduce a post in WBF by Tom Danley that explains this much better than I ever could .. Let me know if this admitted in which case I will post it. The gist of it is that an SPL meter typically would not measure that kind of SPL instantaneous variations. For that one needs an oscilloscope. Assuming ( a big one BTW) that a given recording would preserve those instantaneous peaks, a low sensitivity speaker cannot reproduce these even with a very powerful amplifier, it power compression level would be quickly reached. We must remember that that the scale in volume level is logarithmic and the arithmetic of amplifier output level quickly shows that a 500 wpc amplifier is only 6 db above a 125 wpc one ... and a 1000 watts 9dB... Amplifier power may be plentiful but few amplifers are able to deliver 1000 watts cleanly ..moreover few voice coils are able to take that amount of power even for milliseconds, even if they could , they would compress the signal ... This level of compression is not even measured or disclosed regularly by speaker manufacturers nor magazines... Ultra sensitive speakers aren't immune to power compression but it happens at much higher SPL. Even taking the case where the rated sensitivity is not that high, designs considerations within the speaker itself may take care of this power compression. Taking 2 specific examples the JBL M2 and the 4367 ( perhaps other member of the JBL family share this): their drivers are build to take a lof power especially the M2... and to reproduce higher SPL level in the process.. thus instantaneous peaks are better preserved/reproduced. I have heard the JBL DD68000 and this one thing that comes to mind when listening to it .. the ease with which it goes from very soft to very loud..
I don't have much measurements at hand to show this but I believe this is the main reason why high sensitivity speakers sound the way they do: To my ears they sound different. For example there is a family sound between the Revel line and the JBL Synthesis, to my ears the TOL Revel sound restrained compared to the JBL Synthesis models... Of course my evaluations were sighted ... JBL horn ( CD?) speakers in my future for sure: M2 or K2 or S9700 or 4367 for sure or other CD speaker ...
It can be shown that a few keys jingling can produce instantaneous SPL peaks up to 120 dB @ 1m ... I learned this from a WBF post by the eminent Tom Danley of Danley Audio fame. Low sensitivity speakers even when driven by 1000 watts amplifers can't reproduce that kind of level ... for the sake of argument and since we're a Science forum a 85 dB speaker would need 2000 watt to reproduce that kind of level while a 105 dB would only need 100 watts! You can see where this is going.
If this is accepted I could reproduce a post in WBF by Tom Danley that explains this much better than I ever could .. Let me know if this admitted in which case I will post it. The gist of it is that an SPL meter typically would not measure that kind of SPL instantaneous variations. For that one needs an oscilloscope. Assuming ( a big one BTW) that a given recording would preserve those instantaneous peaks, a low sensitivity speaker cannot reproduce these even with a very powerful amplifier, it power compression level would be quickly reached. We must remember that that the scale in volume level is logarithmic and the arithmetic of amplifier output level quickly shows that a 500 wpc amplifier is only 6 db above a 125 wpc one ... and a 1000 watts 9dB... Amplifier power may be plentiful but few amplifers are able to deliver 1000 watts cleanly ..moreover few voice coils are able to take that amount of power even for milliseconds, even if they could , they would compress the signal ... This level of compression is not even measured or disclosed regularly by speaker manufacturers nor magazines... Ultra sensitive speakers aren't immune to power compression but it happens at much higher SPL. Even taking the case where the rated sensitivity is not that high, designs considerations within the speaker itself may take care of this power compression. Taking 2 specific examples the JBL M2 and the 4367 ( perhaps other member of the JBL family share this): their drivers are build to take a lof power especially the M2... and to reproduce higher SPL level in the process.. thus instantaneous peaks are better preserved/reproduced. I have heard the JBL DD68000 and this one thing that comes to mind when listening to it .. the ease with which it goes from very soft to very loud..
I don't have much measurements at hand to show this but I believe this is the main reason why high sensitivity speakers sound the way they do: To my ears they sound different. For example there is a family sound between the Revel line and the JBL Synthesis, to my ears the TOL Revel sound restrained compared to the JBL Synthesis models... Of course my evaluations were sighted ... JBL horn ( CD?) speakers in my future for sure: M2 or K2 or S9700 or 4367 for sure or other CD speaker ...
The keys jangling, door slamming, etc. examples have been with us "forever". My take has always (for decades) been that they are not that loud heard from ten feet away, no recording media has that sort of dynamic range (not true now with digital but tape and vinyl do not), and 120 dB (I have read up to 140 dB for various "real world" experiments) is loud enough that most folk are going to turn it down anyway. Make it half as loud, i.e. drop the level by 10 dB, and you only need 1/10th the power. Even if my system could reproduce the sound of a live gunshot at the barrel or jet engine from ten feet away (other common examples), I wouldn't want it to. So, while the examples are valid and reproducible (mostly), IMO (and I mean exactly that) in practice the implications are much less dire and most folk get along OK with speakers having less than 100 dB efficiency, less than 1000 W/ch, and can live with the attendant constricted dynamic range. Massive dynamic range (DR) is worth having, of course, but there are other things that play into building a system we like to hear.
Most high-efficiency speakers I have heard use horns, and compression drivers and their horns tend to have different frequency and dispersion characteristics than conventional speakers. Not that they aren't generally cleaner (lower in distortion) and exhibit excellent dynamic range due to their high sensitivity, but I don't think that is the only or even major parameter affecting how they sound.
IMO - Don
Most high-efficiency speakers I have heard use horns, and compression drivers and their horns tend to have different frequency and dispersion characteristics than conventional speakers. Not that they aren't generally cleaner (lower in distortion) and exhibit excellent dynamic range due to their high sensitivity, but I don't think that is the only or even major parameter affecting how they sound.
IMO - Don
Waiting for some input from @RayDunzl , not sure what measurement equipment he uses, he routinely measures much higher instantaneous peaks than are oft reported. (IIRC)
I figure unless your meter has a "Peak" function (not MIN/MAX) - it is integrating/averaging the level over a short period of time.
Typical is A/C weighting, slow and fast integration, MIN/MAX hold.
MIN/MAX displays the lowest/highest averaged levels, not Peak.
I have a UMIK-1 and REW - the integrating measurements there match my cheap averaging handheld meter, the peak readings make sense in the context of my measurements.
Example:
Unweighted (no filter), C weighted, and A weighted measurements of room background and a single hand-clap at about 5 feet off to the side.
Numbers on the left are fast averaged and weighted min and max, and unweighted peak.
From REW Help File:
The meter displays either sound pressure level (SPL), time-average equivalent sound level (Leq) or sound exposure level (LE) according to the selection made on the buttons below the display. The SPL reading is filtered with either a "Fast" (125ms) or "Slow" (1s) time constant, selected via the F/S buttons.
---
My normal-efficient panels (about 88dB @ 2.83v at the listening position) showed no onset of compression on sweeps up to 95dB or so (which is not saying a lot, but that's what I looked at).
They have produced 116.9dB on some drumming peaks at the listening position, which was so loud as to border on the ridiculous/dangerous, so I don't do that. It was a brief calibrated experiment.
110dB peaks is about the loudest occasional "normal" Beer Saturday Night peak loud I get here, 105dB commonly seen loud, 100db normal listening loud.
Right now, Charlie Hunter Trio, but from CD:
Here's an informative glossary about Sound Levels:
http://www.acoustic-glossary.co.uk/
Typical is A/C weighting, slow and fast integration, MIN/MAX hold.
MIN/MAX displays the lowest/highest averaged levels, not Peak.
I have a UMIK-1 and REW - the integrating measurements there match my cheap averaging handheld meter, the peak readings make sense in the context of my measurements.
Example:
Unweighted (no filter), C weighted, and A weighted measurements of room background and a single hand-clap at about 5 feet off to the side.
Numbers on the left are fast averaged and weighted min and max, and unweighted peak.
From REW Help File:
The meter displays either sound pressure level (SPL), time-average equivalent sound level (Leq) or sound exposure level (LE) according to the selection made on the buttons below the display. The SPL reading is filtered with either a "Fast" (125ms) or "Slow" (1s) time constant, selected via the F/S buttons.
---
My normal-efficient panels (about 88dB @ 2.83v at the listening position) showed no onset of compression on sweeps up to 95dB or so (which is not saying a lot, but that's what I looked at).
They have produced 116.9dB on some drumming peaks at the listening position, which was so loud as to border on the ridiculous/dangerous, so I don't do that. It was a brief calibrated experiment.
110dB peaks is about the loudest occasional "normal" Beer Saturday Night peak loud I get here, 105dB commonly seen loud, 100db normal listening loud.
Right now, Charlie Hunter Trio, but from CD:
Here's an informative glossary about Sound Levels:
http://www.acoustic-glossary.co.uk/
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REW has a logging function attached to the SPL meter too:
I have the same gear. Is this the calibration routine you used to get it ready?
https://www.roomeqwizard.com/help/help_en-GB/html/inputcal.html
No.
Or Yes if you keep reading.
Download from miniDSP if you don't have a calibration file for your mic - unique by serial number on the mic.
https://www.minidsp.com/products/acoustic-measurement/umik-1
Ah OK thanks. I already have the umik cal file installed and config'd like that, so guess I'm good to go.
One more question. Do you keep REW updated to the latest beta or only the latest stable release?
If the big number in the SPL meter is white, it thinks it is "calibrated", red, not.
If you have an SPL meter (handheld) compare readings - if within a dB or two, say "Looks good!" and move on.
New when I feel like it.
I use the multi version, can run more than one instance at a time, to look at the room and the source at the same time. You may or may not want to do that.
This has become a very informative and useful thread. thanks guys
Looks to be peculating as expected. A quick screenshot of the Nascar race on TV right now.
My experience has been that competence, not power is needed - 60W amps driving average sensitivity speakers easily produces satisfying sound levels, provided all of those 60W can always be used ! On modern compressed pop this will cause mental overload at high volume, and your ears will be ringing within 5 minutes.
One of the things that has to be got right when using a quality system is to make sure that the adjustment of gain has plenty of range, at the maximum end - a 'problem' I've had with many of my setups is that this was limited, and on recordings that were mastered at a low level, the maximum setting was barely loud enough - one doesn't want to be constrained by poor choices.
BTW
Don't want to take this thread too far OT but just a quick post of a room sweep I did while just playing around a few months back. Setup needs more work for sure.
A Norwegian hifi manufcaturer, Kvålsvoll, has posted this calculator on this website btw: http://www.kvalsvoll.com/Articles/AudioCalculatorspl.htm
Allows you to see how much power you need for achieving a certain sound level. You really need a lot of power to achieve peaks of 110 db with inefficient speakers.
Allows you to see how much power you need for achieving a certain sound level. You really need a lot of power to achieve peaks of 110 db with inefficient speakers.
I recently measured 50Vpk across my 4 Ω (nominal) speakers during a period of loudness.
Were that level continuous, the RMS calculation would be
The specification for the amplifiers provides a maximum of 138Vpk across the speakers
... which shall forever remain unexplored
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