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In Reply to: RE: I wonder... posted by djk on April 05, 2015 at 23:06:17
"A friend has some custom speakers that are 107dB/2.83V/1M.
Most of the time he is listening to 100mW or so, the quality of the program material just isn't all that good.
Two albums cause him to run his 200W/8Ω amplifier into clipping (the Sheffield Drum Record being one)."
That would be over 130db.
I can, with a high degree of certainty, say that your friend has hearing damage.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Follow Ups:
"I can, with a high degree of certainty, say that your friend has hearing damage."No, not necessarily, it's complicated and has to do with dynamic range and the difference between what sounds loud to ones ears and what is actually required to reproduce a signal.
Your sense of "loudness" is something like a medium speed average like what you see when you use a sound level meter on "fast".
That being said, at the level of an electrical signal, for a given "average" level, there is a "peak" level and minimum level within that time period of the average.
For some pretty compressed music this can be 10dB, that is to say the instantaneous peaks can be 10 times greater than the average.
That is what they mean when one hears "peak to average ratio".
Highly dynamic sources that were not compressed as much can have much larger peak to average ratio's, at 20dB, the peaks are 100 times larger than the average or what it sounds like so far as loudness while 30dB requires 1000 times more than the average level or power to reproduce correctly. Beyond that, he may actually have a high efficiency system but how far down does it go? There is no way without great size to have high efficiency low frequencies and that is where most of the power usually goes.
Sadly, looking at what is required to capture even everyday sounds, our sound systems cannot reproduce many sounds in nature.The weird part too is that while everyone knows what clipping sounds like, hardly anyone realizes that very short or single cycle clipping isn't audible as a flaw but only audible when compared to an unclipped signal which will be more "dynamic" but not necessarily louder.
Hope that makes sense
Best,
Tom Danley
Danley Sound Labs
Edits: 04/07/15
"Beyond that, he may actually have a high efficiency system but how far down does it go? There is no way without great size to have high efficiency low frequencies and that is where most of the power usually goes."
I made assumptions. I took him at his word.
"A friend has some custom speakers that are 107dB/2.83V/1M."
I assumed that the custom speakers were full range and 107db.
I guess I would need to know the particulars of his system and the type of music he listens to.
I have 97db speakers and I can't imagine listening while a 200 watt amp was being clipped.
I only have one pair of ears and I don't want them damaged.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Tre I also use speakers that are sensitive. They have a rating of 95.6dB. These are the Dayton PS220-8, but mine have highly treated cones. These in turn are loaded in Sachiko double-back-loaded horns. So I don't know if that raises their overall sensitivity rating or not. But for the sake of this discussion, let's assume they're 95db, ok? I use these with a 40W/ch, 845-based, SET amp/integrated amp. Now I can play Symphony music and or Progressive Rock music at levels that are so loud, you literally have to leave the room! You don't leave because of distortion, but rather due to the sheer volume of the music being played.When I play music this loudly ---{ which isn't very often }--- if I walk through the kitchen ---{ which is just to the left of the audio system }--- and I sit in the dining room at the table. I'm now about 25'+ from the system and at this location the music is crystal clear and just incredible to listen to. I simply couldn't imagine trying to attempt to listen to the music at my "normal" location in the audio room when played at these volumes. I think anyone who would is either hearing impaired or crazy...
I'm listening to Afterdark by Halie Loren
Thetubeguy1954 (Tom Scata)
Central Florida Audio Society -- SETriodes Group -- Space Coast Audio Society
Full-range/Wide-range Drivers --- Front & Back-Loaded Horns --- High Sensitivity Speakers
Edits: 04/10/15
Hi Tre
To be clear, your ears will reliably tell you how loud something sounds and one should avoid exposure to that kind of sound.
That being said technically speaking, there is a large difference between the amplifier signal needed to reproduce a given signal and how loud that particular signal might sound.
For instance, playing a record with a tiny scratch, that "tick" might be a large enough signal to require a very large peak or might even clip with a smaller amplifier yet it doesn't "sound" loud at all because it is so short as your sense of "loud" is an average over a short time.
On the other hand, a steady mid range tone will sound very loud at a vastly lower actual power level.
This matters when you want to play older or now specialty hifi recordings which generally had / have much more dynamic range than the typical modern mp-3 or most "re-mastered" old recordings.
You can often tell if you have a modern or old recording by how high you have to turn the volume knob to be at the right listening level.
The loudness wars in the recording industry have brought us recordings that are compressed and as hot as can be recorded, using a recording medium that has never had more dynamic range available.
Ironic
If you're not bored to tears by now, here is a little application that lets you examine audio files like a VU meter but shows slow average, fast and peak signal levels playing a music file.
http://www.orban.com/meter/
Or this?
Sound Forge 8
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
YES that will do as well, also Cool edit had that feature.
Note here the peak level is about 18dB over the RMS level which means the peak power is nearly 100 times the avg in that particular recording.
Best,
Tom
Irony indeed. We can record 130 plus decibels on a Blue Ray, and the idiot powers that be force engineers to produce 2 db of dynamics where everything screams at you all at one.
Deplorable.
Yeah it is so weird, it's kind of like they perfected the paper making process just as the artists switched to drawing with burnt sticks and feces.
People wonder why music often doesn't sound "real" haha
Even with simple passive networks of yesteryear, the most "real" sounding music I have had in my listening room in the last 40 years have come from Jazz recordings, instrumentals or vocals, through speakers you have designed. This comes from a music lover with an engineering, trumpet, and drums in his musical background. We won't even discuss the garage band periods.Even though we have diminishing returns in 24 bit depth and enough 192 Khz. resolution to please the world's bat population (overkill IMHO) music recordists don't even take full dynamic advantage of the "lowly" CD!! As former member of the AES in the mid 70's, I remember hearing a DBX compander system, which gave us a glimpse into what the upcoming CD might sound like..............amazing over Khorns at the time.
Well recorded DYNAMICS over horn loaded speakers is the only thing that can give us any illusion of reality. Everything else sounds soft and laid back to my ears. Most "audiophiles" simply don't get it and never will.
I really got a laugh with your burnt stick analogy. LOL.
Edits: 04/08/15 04/08/15
Having had AER/back-loaded horns in the past, and listened to many examples, I had recently drifter away from horns for any number of reasons (can't accommodate things like Bionors or find ones like TP1s or Hegemans, etc).
But a friend is going through the process of slowly modifying his Klipsch Khorns with ALK crossovers, and B&C drivers. Combined with his high-mass plattered Garrard 401, I was completely bowled over by a sound I've not heard since listening to Vitavox-based horn systems. Effortless dynamics, tonally accurate and easy-sounding waves of sound - without honk, shout or other parasitic noises. Just great.
Now my recently acquired stacked ESL57s seem something of a diversion from 'the path'.
Big J
"... only a very few individuals understand as yet that personal salvation is a contradiction in terms."
Hi Claude!
I remember as my audio system slowly became better and better. I noticed I was purchasing less & less Progressive Rock ---{ which I really love to this day }--- by YES, EL&P, Genesis, Triumvirate etc. and more & more Jazz! The Jazz just sounded much better to these ears. It took awhile for the Prog-Rock to wane and Jazz to wax. But, thankfully due to the much better sonics of Jazz recordings, not as long as I would have thought!
I'm listening to Afterdark by Halie Loren
Thetubeguy1954 (Tom Scata)
Central Florida Audio Society -- SETriodes Group -- Space Coast Audio Society
Full-range/Wide-range Drivers --- Front & Back-Loaded Horns --- High Sensitivity Speakers
"I can, with a high degree of certainty, say that your friend has hearing damage."
No, you can't.
You have no idea of the listening distance, the spectral content, and the peak-to-average ratio.
Yes, I made some assumptions.
I assumed that he is listening in doors.
I assumed that he is listening to music.
I assumed that he is listening to music with peaks about 12 to 15db above average.
Most listening rooms have a reverberant field that starts about 1 meter from the speaker so the db loss do to distance does not apply.
Two 107db speakers with 200 watts into each speaker would give over 130db spl in room.
Even if the music he listens to has peaks 20db above the average then he would be subjecting his ears to 110db.
That will do permanent damage in a very short time.
Just be careful. We only get one pair of ears.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
The dB police would shut down live acoustic music if they could.
A friend of mine plays(acoustic)violin with a country band on weekends. He owns about five violins, and takes one that is most suited to this use. It is so loud that he usually plays with a mute, yet the pedal steel guitar guys with their twin 15s and 500W amplifier cringe. This is NOT his loudest violin either.
I listened to an acoustic jazz quartet with a Grammy award trumpet player. and thought to myself 'it needs to be louder'. It would have been a good level in a small jazz club, but we were in a well damped 3500 seat auditorium. The woman I was with (my mother) thought it was too loud, and doesn't appreciate music.
As regards OSHA and absolute levels, music is not the same as noise. A noise level that would have you cringing in a factory, and tensing your ears, does not have the same (hearing damage) effect on music. There are studies in the literature that show this, but the dB police don't want to hear this, and so they ignore it.
Dance music can take a lot of flack. The SPL levels are mostly bass though. OSHA 'A' scale readings roll-off the bass at a 6dB/oct rate below 1Khz. So a 105dBA exposure for one hour could hit 130dB at 40hz and be OK. Too damn loud, you bet. Damaging levels, not according to OSHA. It's usually the excessive treble that gets crowd complaints (the bass gets the neighbors complaining).
Car stereo with its 150+ dB peak levels is another issue. I will not get in a car that can play louder than about 130dB, even if I am wearing full coverage ear protection, bone conduction will get you.
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