Perhaps I did miss your original point. My apologies.
I agree that it is probably not primarily designed for emergency use: If it were, it wouldn't have ratchet stops by default, but only on activation by a lever/knob/whatever.
My main point is that it's still applicable to emergency situations, even if it's not designed for that. Do what you can with what you've got, and understand it before you need it. Case in point: My BMW has a separate drum assembly inside of the rear discs: Whether designed for emergency use or not, it's a mechanically-operated braking system which has no meaningful reliance on the service brakes, and I'm certainly going to be using it if the master cylinder fails suddenly. I'll also be downshifting like a fool (damn the pistons and valves, and fuck the clutch), and doing whatever else I can do to introduce drag.
A dear friend of mine is on my couch right now watching a movie, as he slowly recovers from a truck accident over a year ago where his rig went off of a cliff. He technically died more than half a dozen times, and was bent in half backwards with the engine on top of his crumpled mess-of-person, burning him silly. (He's doing pretty well, his pronounced limp is lessening, and he recently got his CDL reinstated, but may not be able to physically tolerate driving an OTR truck ever again.)
When it comes down to it, it doesn't matter at all if the gear (or the gearbox, or the load, or anything else) survives as long as the occupants and the bystanders do. Grab whatever you can (FFS, drag your bootheel on the ground if that's all you've got left) and keep trying.
Yes, you should try learning new things, by perhaps driving some cars that don't have the parking brake in the middle. I've performed emergency stops with some, and it's dangerous.
I prefer to avoid situations that require emergency stops.
That said, I've got my time in on modulating the foot-operated parking brake in a towed vehicle, thus using the cable-operated rear drums to stop two vehicles at once. It ain't so bad.
And my work truck has a foot-operated parking brake. I'll put my health and safety where my mouth is, and practice on it the next time it's convenient.
I've also driven my share of manual transmission cars/trucks which either did not have power steering or (worse) which had inoperative power steering. It sucks trying to steer with one hand and do other stuff with the other, but it's doable. And you'd bet your ass I'd be doing it without complaint if my life depended on it.
You might also try performing an emergency stop with an air brake system when your secondary tank line bursts. I've done it, and believe me, stopping an 80,000lb vehicle with your air pressure gauge dropping like mad is something you'll never forget.
Quoth Wikipedia: An air pressure failure at any point would apply full spring brake pressure immediately. I parse this to mean that you'll get some aspect of brakes eventually whether you want them or not, and that planning accordingly and thinking ahead would be a Good Move. Also helpful is the fact that air brake systems can be proactive in alerting the driver to a leak, since with simple hydraulic brakes one doesn't know about a such failures until one tries to stop. It's entirely possible for an air brake system to be in the throes of death, notice this long before the brakes are needed for anything, and bring the rig to a safe stop at an appropriate...but generally impossible to do this with hydraulic brakes.
On a real truck, you might also have a jake brake, a multitude of gears to work with, and a clutch made for controlled slipping (more heat generated == less forward momentum). Boon!
Back to the point: It's not perfect (nothing is, or this wouldn't even be a discussion). But using the parking brake in an emergency involving complete loss of service brakes is a fuckton more likely to be survivable than the other primary option (prayer), even if it's inconvenient or downright difficult to accomplish. Just like in any other emergency, it's important to know what resources you have and be able to use all of them as necessary.
Hold the release button/lever/widget as you operate the brake, thus disengaging the ratcheting mechanism that makes it function as a parking brake. They then are able to be modulated just fine, just as cable operated brakes do on all manner of moving machinery (from early automobiles, to industrial machines, to modern bicycles).
Ah, French automobiles. An endless source of amusement.
Good of them to put real(ish) secondary brakes on the front, though: That's where it really makes a difference, if one ever has to use them to slow down and stop.
You can tell by the fact that it's meant to lock in place, which is dangerous for a moving vehicle.
The only thing that keeps the secondary brake locked in place is lack of driver skill. It can be modulated very easily if one is aware of its correct operation.
(Been there, done that. You should try it sometime. It's good to learn new things, especially when it comes to understanding how to most safely stop a vehicle in the face of mechanical failure.)
There's a lot of ways to dump speed in a car. The easiest is just downshifting as appropriate. Turn the AC on for a little increased drag. Use the secondary brake (e-brake, parking brake, whatever-brake) to actually stop after you've already dumped as much speed as you can using any other means you can come up with.
My E36 BMW has what you might call an "emergency brake": The inside surface of the rear discs is machined and used as a drum, with shoes which can only actuated by the handbrake lever, and the normal service brake uses an uncomplicated hydraulic disc/caliper arrangement.
It's really not all that uncommon and the result is that it has independent control linkages, and independent friction surfaces. It shares the rotating parts of the wheel/hub assembly and the suspension bits, but if those items are lost for any reason braking on that corner simply isn't going to be happening anyway. (Especially on your '64 Dodge, where loss of one rear wheel results in the inability to brake the other one using the "redundant system" you speak so fondly of.)
What were you going on about, again? Oh, yeah: Nostalgia. No, they don't make 'em like they used to. Sometimes, they make 'em better.
If we extrapolate "headphones" from conventionally head-worn items to floor-standing monstrosities that can be used by more than one person at one time, then I might say that I already have the correct headphones.
a 2004 pop CD was quantized to levels once exclusively the realm of a Telarc *DIGITAL CANON* in a recording of 1812 Overture whose main purpose was to show off your kilowatt-RMS amp and array of subwoofers
Although I agree with your main point, I gotta ask: WTF are you going on about? What is a "*DIGITAL CANON*"?
They were real cannons, recorded separately and mixed in later. Indeed, the original Telarc recording shattered some of the windows of a nearby building, as discussed in the liner notes. Telarc has historically been very open very open about explaining their recording processes...especially when they're particularly unusual or amusing.
I own this CD, and if I could be bothered to find it I'd post the verbiage verbatim.
That all said: I once heard a Telarc recording of the 1812 played over a reasonable PA system at a 4th of July fireworks show at a campground. Things were good until the first cannon shot audibly mangled the woofers, and the second disabled most of them (subsequent blasts took the rest of 'em down).
It was the grand finale, though, so I guess it was all in good fun.
Wrong on all counts. A 12dB increase is not "8x as loud." It's not even 8x the power, but 16x the power (power doubles with every increase of 3dB). Either you don't understand what you're going on about, or you're just wrong and don't realize it (because any answer resulting in the number 8 is always wrong in this particular scenario).
Loudness, as perceived by humans, is generally considered to double with every 10dB of increase. Hence, the convenient unit that is the Bel: 1 Bel == double the volume == 10 deciBels. (And also conveniently, a 10dB increase requires 10x the power.)
So, more properly: A 12dB increase might be appropriately described as being "a little more than twice as loud," once it's all said and done.
And IMHO "a little more than twice is loud" is still waaaay too much difference between program material and advertising material. There's no need to exaggerate what the numbers mean.
I maintain that a movie only needs four channels, one at each corner of the screen.
That's an interesting concept that I've never considered before. I like it, a lot, for all of the same reasons you've surely already thought of...
That said, I think 5 would be good: One slightly below the geometric center of the screen (where the mouth is) would be a blessing for listeners who are well off-axis.
Too much inertia for it to ever work, though. Which is a bummer.
IIRC, rear speakers were always a misapplication, and both Dolby and Lucas have always wanted the surround speakers to the side (except in 7.1 configurations, where the extra 2 channels are actually intended for rears).
Place them just high enough that they're not completely blocked by the person-sitting-next to-you-on-the-couch's head, and (this is the important part!) aim them at the listener(s). Done.
I used to think the same way, until very recently when I ran into a few low-cost upgrade opportunities which sent me straight from having an awesome stereo to instead having an awesome surround system. I approached it with trepidation, and I didn't think I'd enjoy it as much as I do. Here's what I've learned as I implemented it in peices:
2.1 is fun for movies, even with full-range speakers that are capable of doing Real Bass all by themselves. With the boom channel, the rumble of the explosions find themselves coming out of the subwoofer, which allows the mains to expend their effort doing just music and dialog: Things are closer to what the engineer intended, while tending to also become cleaner at the same time.
IOW, it's perfectly reasonable to set up a modern home theater receiver so that the left and right channels are full range, and the "subwoofer" (in quotes because it becomes somewhat a misnomer in this configuration) only plays the.1 boom channel. In this way, nothing is taken away from the full range outputs.
3.0/3.1 is fun because dialog gets glued to the screen, period. (And no, you'll not find a pair of speakers which can image properly for everyone seated in my particular living room. It is an impossibility due to the angles involved. A center channel helps dramatically.)
5.1 is fun because there are interesting things coming from the rear speakers if the engineer decides to put interesting things there. And listening in 2.0 isn't the same as what they used when the recorded the soundtrack: What would've been the rear channel(s) is not simply truncated. Instead, it gets pushed to the front, sometimes with Pro-Logic-esque encoding (which causes it to be 180 degrees out-of-phase between your left and right speakers). 5.1 is also fantastic for gaming, if you're into that.
$10-15k? I know you're trying to be snarky, but that's nowhere near enough cash. I've got parts which total about $25k (new) in my home theater, and it just does 5.1.
FFS, my CD player alone cost some schlep $8,000.00 not so many years ago.
But forget the silly-expensive end of audio. 64 channels of audio that's actually worth a fuck at all just ain't happening for low 5-digit prices, especially if someone needs paid to install it.
64 speakers and 64 amplifier channels and 64 pairs of speaker wire == $$$. $10-15k would indeed be a bargain.
The only explanation I have for such atrocities is that the market (which is driven by software at the moment) is simply moving too fast for them to be able to keep up, even on high-margin items. By the time the thing gets even close to finished, it's already very outdated compared to everything else, and few people want to spend that sort of money on old tech when they're looking for the auspices of new tech.
The product then bombs, never really gets finished (even though it's been released) because the sales numbers can't support it, and then the vicious cycle repeats for the next product...
Currently it seems like it's better to buy 100 semi-disposable cheap devices that actually work than 10 that are allegedly ruggedized but which can never be as practical or useful.
I've run multi-user Linux boxes that did mail and Apache and BIND and whatever random stuff a shell user wanted, plus Netscape for multiple X servers on the local LAN. (The box itself was essentially headless.)
It was peppy enough, for the time, with less than 64MB of RAM. And it was a 486. And it was a long time ago.
Just the same: I'm continually saddened by the fact that I sit before a monumentally-superior machine, but still doing mostly the same things I was then, and still waiting just as long for the programs to load and Get Things Done as I used to on far-lesser hardware.
Indeed, it troubles me that my dual-core 1.2GHz smartphone with 1GB of RAM is so limited in what it can do, these days. It often seems as if progress is meaningless.
Easy. Being environmentally-aware (reduce, reuse, recycle) is important to folks these days. Drinking recycled beer (aka Corona) is better for Mother Earth than drinking new beer.
Everyone else seems to understand this, and feels a pang of regret whenever they snap the top off of a freshly-brewed beer. I'm alarmed that you don't.
I've done some work with Motorola's portable business-oriented gadgets, mostly stuff that showed up with their acquisition of Symbol Technologies, and all I can say is this: Meh.
Everything I've used from them is either poorly supported or negatively supported. Documentation that is either far too lengthy and wrong or just plain non-existent. Software that, in the best case, barely works. Firmware full of bugs. 802.11 radios that don't really like dealing with 802.11. No ability to get anything pushed up the ladder to the dudes who can actually fix stuff, no matter how many thousand units you'd love to buy if the fucking things would actually work.
Based on this dreary track record of failure, frustration, and despair, I hasten to say that I'm not looking forward seeing what comes out of this deal.
(I'd post more details, but dealing with other Motorola products that actually work (such as their 2-way radios) is a big part of my bread-and-butter, and I'm allergic to posting as AC.)
The attraction of tube amps is the lack of crossover distortion that plagues many transistor designs. By using a simple circuit with couple of high power tube devices, you avoid the distortion products caused by using the hundreds of low power transistors in a modern opamp/mosfet type transistor amplifier.
You're describing the difference between class A and class AB amplifiers, not the difference between tubes and transistors.
Either class of amplifier can be built with either type of component.
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Perhaps I did miss your original point. My apologies.
I agree that it is probably not primarily designed for emergency use: If it were, it wouldn't have ratchet stops by default, but only on activation by a lever/knob/whatever.
My main point is that it's still applicable to emergency situations, even if it's not designed for that. Do what you can with what you've got, and understand it before you need it. Case in point: My BMW has a separate drum assembly inside of the rear discs: Whether designed for emergency use or not, it's a mechanically-operated braking system which has no meaningful reliance on the service brakes, and I'm certainly going to be using it if the master cylinder fails suddenly. I'll also be downshifting like a fool (damn the pistons and valves, and fuck the clutch), and doing whatever else I can do to introduce drag.
A dear friend of mine is on my couch right now watching a movie, as he slowly recovers from a truck accident over a year ago where his rig went off of a cliff. He technically died more than half a dozen times, and was bent in half backwards with the engine on top of his crumpled mess-of-person, burning him silly. (He's doing pretty well, his pronounced limp is lessening, and he recently got his CDL reinstated, but may not be able to physically tolerate driving an OTR truck ever again.)
When it comes down to it, it doesn't matter at all if the gear (or the gearbox, or the load, or anything else) survives as long as the occupants and the bystanders do. Grab whatever you can (FFS, drag your bootheel on the ground if that's all you've got left) and keep trying.
Good luck.
I prefer to avoid situations that require emergency stops.
That said, I've got my time in on modulating the foot-operated parking brake in a towed vehicle, thus using the cable-operated rear drums to stop two vehicles at once. It ain't so bad.
And my work truck has a foot-operated parking brake. I'll put my health and safety where my mouth is, and practice on it the next time it's convenient.
I've also driven my share of manual transmission cars/trucks which either did not have power steering or (worse) which had inoperative power steering. It sucks trying to steer with one hand and do other stuff with the other, but it's doable. And you'd bet your ass I'd be doing it without complaint if my life depended on it.
Quoth Wikipedia: An air pressure failure at any point would apply full spring brake pressure immediately. I parse this to mean that you'll get some aspect of brakes eventually whether you want them or not, and that planning accordingly and thinking ahead would be a Good Move. Also helpful is the fact that air brake systems can be proactive in alerting the driver to a leak, since with simple hydraulic brakes one doesn't know about a such failures until one tries to stop. It's entirely possible for an air brake system to be in the throes of death, notice this long before the brakes are needed for anything, and bring the rig to a safe stop at an appropriate...but generally impossible to do this with hydraulic brakes.
On a real truck, you might also have a jake brake, a multitude of gears to work with, and a clutch made for controlled slipping (more heat generated == less forward momentum). Boon!
Back to the point: It's not perfect (nothing is, or this wouldn't even be a discussion). But using the parking brake in an emergency involving complete loss of service brakes is a fuckton more likely to be survivable than the other primary option (prayer), even if it's inconvenient or downright difficult to accomplish. Just like in any other emergency, it's important to know what resources you have and be able to use all of them as necessary.
Hold the release button/lever/widget as you operate the brake, thus disengaging the ratcheting mechanism that makes it function as a parking brake. They then are able to be modulated just fine, just as cable operated brakes do on all manner of moving machinery (from early automobiles, to industrial machines, to modern bicycles).
Ah, French automobiles. An endless source of amusement.
Good of them to put real(ish) secondary brakes on the front, though: That's where it really makes a difference, if one ever has to use them to slow down and stop.
Move the gearshift to one of the lower ranges. It will downshift.
People have been downshifting in automatics in the mountains for as long as there has been automatics.
The only thing that keeps the secondary brake locked in place is lack of driver skill. It can be modulated very easily if one is aware of its correct operation.
(Been there, done that. You should try it sometime. It's good to learn new things, especially when it comes to understanding how to most safely stop a vehicle in the face of mechanical failure.)
There's a lot of ways to dump speed in a car. The easiest is just downshifting as appropriate. Turn the AC on for a little increased drag. Use the secondary brake (e-brake, parking brake, whatever-brake) to actually stop after you've already dumped as much speed as you can using any other means you can come up with.
My E36 BMW has what you might call an "emergency brake": The inside surface of the rear discs is machined and used as a drum, with shoes which can only actuated by the handbrake lever, and the normal service brake uses an uncomplicated hydraulic disc/caliper arrangement.
It's really not all that uncommon and the result is that it has independent control linkages, and independent friction surfaces. It shares the rotating parts of the wheel/hub assembly and the suspension bits, but if those items are lost for any reason braking on that corner simply isn't going to be happening anyway. (Especially on your '64 Dodge, where loss of one rear wheel results in the inability to brake the other one using the "redundant system" you speak so fondly of.)
What were you going on about, again? Oh, yeah: Nostalgia. No, they don't make 'em like they used to. Sometimes, they make 'em better.
If we extrapolate "headphones" from conventionally head-worn items to floor-standing monstrosities that can be used by more than one person at one time, then I might say that I already have the correct headphones.
Although I agree with your main point, I gotta ask: WTF are you going on about? What is a "*DIGITAL CANON*"?
They were real cannons, recorded separately and mixed in later. Indeed, the original Telarc recording shattered some of the windows of a nearby building, as discussed in the liner notes. Telarc has historically been very open very open about explaining their recording processes...especially when they're particularly unusual or amusing.
I own this CD, and if I could be bothered to find it I'd post the verbiage verbatim.
That all said: I once heard a Telarc recording of the 1812 played over a reasonable PA system at a 4th of July fireworks show at a campground. Things were good until the first cannon shot audibly mangled the woofers, and the second disabled most of them (subsequent blasts took the rest of 'em down).
It was the grand finale, though, so I guess it was all in good fun.
Wrong on all counts. A 12dB increase is not "8x as loud." It's not even 8x the power, but 16x the power (power doubles with every increase of 3dB). Either you don't understand what you're going on about, or you're just wrong and don't realize it (because any answer resulting in the number 8 is always wrong in this particular scenario).
Loudness, as perceived by humans, is generally considered to double with every 10dB of increase. Hence, the convenient unit that is the Bel: 1 Bel == double the volume == 10 deciBels. (And also conveniently, a 10dB increase requires 10x the power.)
So, more properly: A 12dB increase might be appropriately described as being "a little more than twice as loud," once it's all said and done.
And IMHO "a little more than twice is loud" is still waaaay too much difference between program material and advertising material. There's no need to exaggerate what the numbers mean.
That's an interesting concept that I've never considered before. I like it, a lot, for all of the same reasons you've surely already thought of...
That said, I think 5 would be good: One slightly below the geometric center of the screen (where the mouth is) would be a blessing for listeners who are well off-axis.
Too much inertia for it to ever work, though. Which is a bummer.
IIRC, rear speakers were always a misapplication, and both Dolby and Lucas have always wanted the surround speakers to the side (except in 7.1 configurations, where the extra 2 channels are actually intended for rears).
Place them just high enough that they're not completely blocked by the person-sitting-next to-you-on-the-couch's head, and (this is the important part!) aim them at the listener(s). Done.
I used to think the same way, until very recently when I ran into a few low-cost upgrade opportunities which sent me straight from having an awesome stereo to instead having an awesome surround system. I approached it with trepidation, and I didn't think I'd enjoy it as much as I do. Here's what I've learned as I implemented it in peices:
2.1 is fun for movies, even with full-range speakers that are capable of doing Real Bass all by themselves. With the boom channel, the rumble of the explosions find themselves coming out of the subwoofer, which allows the mains to expend their effort doing just music and dialog: Things are closer to what the engineer intended, while tending to also become cleaner at the same time.
IOW, it's perfectly reasonable to set up a modern home theater receiver so that the left and right channels are full range, and the "subwoofer" (in quotes because it becomes somewhat a misnomer in this configuration) only plays the .1 boom channel. In this way, nothing is taken away from the full range outputs.
3.0/3.1 is fun because dialog gets glued to the screen, period. (And no, you'll not find a pair of speakers which can image properly for everyone seated in my particular living room. It is an impossibility due to the angles involved. A center channel helps dramatically.)
5.1 is fun because there are interesting things coming from the rear speakers if the engineer decides to put interesting things there. And listening in 2.0 isn't the same as what they used when the recorded the soundtrack: What would've been the rear channel(s) is not simply truncated. Instead, it gets pushed to the front, sometimes with Pro-Logic-esque encoding (which causes it to be 180 degrees out-of-phase between your left and right speakers). 5.1 is also fantastic for gaming, if you're into that.
But headphones will never make my pant legs flap, or cause chunks of plaster to fall from the ceiling.
Where's the fun in that?
Surely you're not planning on plugging those turntables into a noisy wall outlet. Tube amps to drive the synchronous motors in the turntables!
$10-15k? I know you're trying to be snarky, but that's nowhere near enough cash. I've got parts which total about $25k (new) in my home theater, and it just does 5.1.
FFS, my CD player alone cost some schlep $8,000.00 not so many years ago.
But forget the silly-expensive end of audio. 64 channels of audio that's actually worth a fuck at all just ain't happening for low 5-digit prices, especially if someone needs paid to install it.
64 speakers and 64 amplifier channels and 64 pairs of speaker wire == $$$. $10-15k would indeed be a bargain.
Oh, we're full of Motorola TLAs here, too, fwiw.
The only explanation I have for such atrocities is that the market (which is driven by software at the moment) is simply moving too fast for them to be able to keep up, even on high-margin items. By the time the thing gets even close to finished, it's already very outdated compared to everything else, and few people want to spend that sort of money on old tech when they're looking for the auspices of new tech.
The product then bombs, never really gets finished (even though it's been released) because the sales numbers can't support it, and then the vicious cycle repeats for the next product...
Currently it seems like it's better to buy 100 semi-disposable cheap devices that actually work than 10 that are allegedly ruggedized but which can never be as practical or useful.
I've run multi-user Linux boxes that did mail and Apache and BIND and whatever random stuff a shell user wanted, plus Netscape for multiple X servers on the local LAN. (The box itself was essentially headless.)
It was peppy enough, for the time, with less than 64MB of RAM. And it was a 486. And it was a long time ago.
Just the same: I'm continually saddened by the fact that I sit before a monumentally-superior machine, but still doing mostly the same things I was then, and still waiting just as long for the programs to load and Get Things Done as I used to on far-lesser hardware.
Indeed, it troubles me that my dual-core 1.2GHz smartphone with 1GB of RAM is so limited in what it can do, these days. It often seems as if progress is meaningless.
I've done some work with Motorola's portable business-oriented gadgets, mostly stuff that showed up with their acquisition of Symbol Technologies, and all I can say is this: Meh.
Everything I've used from them is either poorly supported or negatively supported. Documentation that is either far too lengthy and wrong or just plain non-existent. Software that, in the best case, barely works. Firmware full of bugs. 802.11 radios that don't really like dealing with 802.11. No ability to get anything pushed up the ladder to the dudes who can actually fix stuff, no matter how many thousand units you'd love to buy if the fucking things would actually work.
Based on this dreary track record of failure, frustration, and despair, I hasten to say that I'm not looking forward seeing what comes out of this deal.
(I'd post more details, but dealing with other Motorola products that actually work (such as their 2-way radios) is a big part of my bread-and-butter, and I'm allergic to posting as AC.)
You're describing the difference between class A and class AB amplifiers, not the difference between tubes and transistors.
Either class of amplifier can be built with either type of component.
It's just like Norton Commander, but pretty!
(this brought to you by my life for Norton Commander going back to MS-DOS on 8088 days)
(also: thanks.)
Other than OS/2's Presentation Manager, anyway.
(And yes, I'm still bitter, and you youngin's can get off of my lawn.)
The Motorola DPC-550 was supported from the early 90s, until the big carriers turned off AMPS sometime a few years ago.
And this speaks nothing of the Western Electric Model 500, first released in 1949, distributed until 1984, and still supported today.