A Question That Has Burned In My Mind For Years...

laatsch55 said:
Absolutely Mark, but alot is quantitative...

I find it amazing after all the electronics, and electromechanical devices a recording goes through that a good system can approach sounding close to a live performance, meaning non amplified instruments..
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Agreed. I run sound for my church, a lot of times I will say to someone “cut about 4db from the upper- mids to this vocal” to cut sharpness. A quantity can and often must be applied to reach a good subjective balance.
 
laatsch55 said:
So differences in frequencies are a result of different voltages??
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I should've included that at that operating voltage the diaphragm movement is still minimal regardless of frequency and not enough to pop it.
Voltage is normally associated with SPL, [the more the louder] and at those minimal voltages there just isn't enough to do damage.
 
laatsch55 said:
So differences in frequencies are a result of different voltages??
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Wider excursions in a transducer create more current. This depends more on amplitude than frequency. Frequency changes in an inductive circuit is what makes your crossover networks operate ( in conjunction with a capacitor).
 
MarkWComer said:
Wider excursions in a transducer create more current. This depends more on amplitude than frequency. Frequency changes in an inductive circuit is what makes your crossover networks operate ( in conjunction with a capacitor).
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Unless you bi-amp with active x-o's.
 
pennysdad said:
I was just referring to your 'inductive circuit - capacitor' bit.
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Right... understood...
But the basic principle still applies.
Although the woofers are fed in a different way, the mid|high will still be subject to a crossover.
 
pennysdad said:
... & yet a microphone does the whole thing with only one tiny little diaphragm.
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tiny size, low mass is key which is achievable with a mic diaphragm since it is just a receiver, not a transmitter.
 
laatsch55 said:
Lively discussion there fellers, thanks Mark, you graphs explain things very well.

I find it amazing a driver can do what it does...even the harmonics..
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The harmonics you are likely referring to come from the mid and tweeter.
 
This discussion has burned out my mind! o_O
 
Next we will talk about how video works and how our eyes can see all those colors :-)

Great stuff indeed.
 
Gepetto said:
Next we will talk about how video works and how our eyes can see all those colors :)

Great stuff indeed.
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What kind of video? Starting with the rotating disc Baird system, Farnsworth’s iconoscope / kinescope system, photomultipliers or CCD sensors?

That’s a deep hole, there!
 
MarkWComer said:
Right... understood...
But the basic principle still applies.
Although the woofers are fed in a different way, the mid|high will still be subject to a crossover.
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I've run active systems forever, even at home.
In my days of working r'&'r all systems were active throughout and generally 4-way [bass, low mid, hi mid, hi] and then multiples thereof. Single, double, quad, etc etc.
... & then there were the concert systems. 100KW plus and growing. Left & right stacks & centre clusters, & then delay towers.
... & then the health authorities started to clamp us down from 135dB SPL's down to 110dB. That's a massive drop.
It's never been the same since. May as well just go home and play a record.
 
pennysdad said:
I've run active systems forever, even at home.
In my days of working r'&'r all systems were active throughout and generally 4-way [bass, low mid, hi mid, hi] and then multiples thereof. Single, double, quad, etc etc.
... & then there were the concert systems. 100KW plus and growing. Left & right stacks & centre clusters, & then delay towers.
... & then the health authorities started to clamp us down from 135dB SPL's down to 110dB. That's a massive drop.
It's never been the same since. May as well just go home and play a record.
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I have to admit that you’re in a completely different world from me. No experience with active bandwidth separation whatsoever. I understand why these methods were used, never used them myself. Looks like I need to do some reading!
 
pennysdad said:
I've run active systems forever, even at home.
.
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This looks like an opportunity for me to ask some questions...

I want a subwoofer! I like my ADS 1290 speakers, except one thing: they’re a bit thin on the bass. I can drive them harder with an EQ, but then I hit a limit to the cone excursions.

I’ve been looking at a Klipsch (recommend another, if you want..) sub. I see that they have connections from the amp and then to the speakers. This is an active xo, correct? Or should I connect the pre out to an active xo and feed two separate outputs (now that I have two amps). For the second option, I want to keep the higher bass directed to the 1290s, and the extreme bottom to the sub- I suppose these xos are tunable?

I have no experience with these, as I’ve said before, I’m curious to hear your thoughts. Thanks!
 
Billboard said:
135db is loud, what bands were running that volume, also who is limiting concert volume? What country?
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ACDC were one. You could hear them from 8km away. Their sound guy was a good mate of mine at the time. Cold Chisel, The Angels [all Ozzie bands] were others. There were lots of bands towards the end of the 80's that were right up there. We [me included] were all pretty mad and it became quite a competition.
Eventually the EPA [in Australia] stepped in and changed everything.

Lots of info can be got here: https://en.wikipedia.org/wiki/Loudest_band but some actual figures were not recognised for some reason or other.

It can be done, as long as it's CLEAN.
 
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