Horn Relay

Originally Posted by the_lone_wolf

i don't think the human ear can hear megahertz

Meh, that's what happens when I debate whilst in the office.

Hertz, couple of hundred hertz difference between the low Nautilus & the Magnum.

[the_lone_wolf]

Originally Posted by Baph

Hertz, couple of hundred hertz difference between the low Nautilus & the Magnum.

makes no difference, the length of the wire still has zero say over the phase of the two horns until you get to the scales i previously mentioned, and the combination of unlikely circumstances that would be required to cause the effect you are proposing are just staggering...

Originally Posted by the_lone_wolf

makes no difference, the length of the wire still has zero say over the phase of the two horns until you get to the scales i previously mentioned, and the combination of unlikely circumstances that would be required to cause the effect you are proposing are just staggering...

That's what you keep saying, so I'll repeat myself too.

It's happened on 3 different bikes (that spring to mind right now), where just changing the length of the wire fixed the lack of audiable sound. Two bikes had Magnums, the other a Nautilus IIRC, all three were SVs.

[the_lone_wolf]

Originally Posted by Baph

That's what you keep saying, so I'll repeat myself too.

fair enough, the main difference being that i can explain why what i'm repeating is correct, and you can't, you can only say "well i messed with it and it must've been this" despite the claim being completely nonsensical

Originally Posted by Baph

It's happened on 3 different bikes (that spring to mind right now), where just changing the length of the wire fixed the lack of audiable sound.

3 different bikes? who were they then? did they all "only change the length of the wire" too?

except you didn't just change the length of the wire though did you? it didn't magically sprout an extra inch, you had to remove and replace the connectors, you had to move your hands in the general vicinity of the horn and the wiring around it, moving all that around too - can you really not see that it's far more likely you had a faulty connection somewhere? or are you simply far too stubborn to admit that you're wrong in saying the length of wire is the cause?

i've shown you why you're wrong in the simplest terms i can think of, i've given sound reasoning and calculations to show how wrong you were, and you simply dismiss it as, in layman's terminology, "theory" and continue to cling to the belief that it's the length of wire and not one of the other far more plausible ideas that could have caused you problems

if you can't understand why the length of the wire has no effect, then there's no point arguing, you obviously don't understand the fundamental basics of how electronics work, and operate on a principle of "well if i plug this in here it makes that happen" without understanding why

if on the other hand, you think you might understand how it works, then please feel free to explain how changing the length of the wire affects the phase enough to cause them to interfere, without just saying "well i changed it and now it works" - i'd wager you can't

Originally Posted by the_lone_wolf

3 different bikes? who were they then? did they all "only change the length of the wire" too?

Myself, fitting two magnums. SoulKiss fitting two Magnums, and Nobbylad had a "flat fart" sounding Nautilus IIRC.

EDIT: I can't guarantee the actions of the others, natrually, as I wasn't there.

Originally Posted by the_lone_wolf

except you didn't just change the length of the wire though did you? it didn't magically sprout an extra inch, you had to remove and replace the connectors, you had to move your hands in the general vicinity of the horn and the wiring around it, moving all that around too - can you really not see that it's far more likely you had a faulty connection somewhere?

If there was a faulty connection, why then, for a good couple of hours, was my DMM telling me there was a current flowing through the horns when I pressed the button, yet no sound was audiable?

Also, from memory, I messed with the horn mounting etc for a good couple of hours, and nothing resolved it. When I changed the wire length, I chopped it from the relay terminal, not the horn connection. I then replaced the single blue spade... but wait, I already said all of this.

Originally Posted by the_lone_wolf

if you can't understand why the length of the wire has no effect, then there's no point arguing, you obviously don't understand the fundamental basics of how electronics work, and operate on a principle of "well if i plug this in here it makes that happen" without understanding why

Now you're starting to get personal. Getting wound up are we?

Originally Posted by the_lone_wolf

if on the other hand, you think you might understand how it works, then please feel free to explain how changing the length of the wire affects the phase enough to cause them to interfere, without just saying "well i changed it and now it works" - i'd wager you can't

It's a little hard to believe theoretical number crunching about an "ideal world" situation when in the real world, it's been done, and repeated more than once.

I fully ackowledge that the difference in time to activate either circuit (classing two horns as seperate circuits for a second) would be minimal.

However, I am firm in my belief that the change in activation time is sufficient that it allows the pulsed charging compressor to increase the offset of the two waves.

For example (and rather a lot of assumptions, but since you require the theoretical "proof" behind the physical evidence), lets assume that the circuits are activated at the exact same instance, and the differences in manufacturing for the compressor and air chamber mean that a sound is emitted from each horn at the exact same instance. This would produce waves that are completely in phase with one another (again, assuming the horns are idenically manufactured).

Now, to achieve exactly opposite phase of the horns, you need a 0.001 second delay for one of the horns to start emitting a sound (by your numbers). Of course, given the various manufacturing differences of the various components, this delay won't actually be 0.001 seconds, but we'll go with that for now.

Since I understand how a compressor works by pulsed charging, I can see that even a very minimal change to the activation time, can mean that an entire pulse is missed, but more than likely it was only approx half a valve cycle. Unfortunately the system we're describing isn't a simple matter of a small fan pushing air through a cone. Missing a whole pulse cycle in a small compressor like this can easily mean 1/8th or 1/4th a second delay on the output (as it's effectively an over-pressure safety valve).

Whilst I can't guarantee the above theory, I can guarantee that I can reproduce the effect physically.

Also, just for the record, the inspiration behind changing the length of wire came from an Acoustic Engineer. In fact, I believe I remember his words being to ensure the horns were turned simultaneously. So please, less of the accusations about lack of understanding.

[the_lone_wolf]

Originally Posted by Baph

Myself, fitting two magnums. SoulKiss fitting two Magnums, and Nobbylad had a "flat fart" sounding Nautilus IIRC.

EDIT: I can't guarantee the actions of the others, natrually, as I wasn't there.

so one example then, as you don;t know what anyone else did?

Originally Posted by Baph

If there was a faulty connection, why then, for a good couple of hours, was my DMM telling me there was a current flowing through the horns when I pressed the button, yet no sound was audiable?

so for two hours, you're saying that you just happened to have the two horns producing perfectly identical waves each time they were activated, exactly 180deg apart in phase, and you managed to keep both of your ears at the exact perfect distance, the integer number of wavelengths, from both horns, at all times, and there was not one echo, not one stray sound that you heard?

can you not see how this makes no sense whatsoever?

Originally Posted by Baph

Also, from memory, I messed with the horn mounting etc for a good couple of hours, and nothing resolved it. When I changed the wire length, I chopped it from the relay terminal, not the horn connection. I then replaced the single blue spade... but wait, I already said all of this.

yes, you did, and it still has no bearing on what caused your problem because it doesn't matter how you look at it, before you messed with it your horns were not producing any sound, they might have been drawing current, but they weren't producing any noise

Originally Posted by Baph

Now you're starting to get personal. Getting wound up are we?

if you want to take it personally that's not my problem, it's not personal to me if it's accurate, and you're not demonstrating a grasp of the processes involved by saying things like "how fast electrons move"

Originally Posted by Baph

It's a little hard to believe theoretical number crunching about an "ideal world" situation when in the real world, it's been done, and repeated more than once.

except you haven't, you think you've managed to create a magic situation where you can produce destructive interference that doesn't require distances and timings to be exact, if you had truly managed to have both horns sounding, there would only be a tiny chance of the wavefronts combining perfectly at a particular point in space to cancel each other out, you wouldn't have just heard nothing no matter where your head was or how many times you activated the switch

Originally Posted by Baph

I fully ackowledge that the difference in time to activate either circuit (classing two horns as seperate circuits for a second) would be minimal.

not minimal, effectively zero, comparing 0.0000000006 seconds to 0.001 seconds is exactly the same as comparing a period of one minute to a period of just over 19 years - they are totally different orders of magnitude

Originally Posted by Baph

However, I am firm in my belief that the change in activation time is sufficient that it allows the pulsed charging compressor to increase the offset of the two waves.

your belief is wrong then, it would have to exaggerate any delay by a factor of 10 million in order to produce the offset, and it would have to do it reliably every time the switch was activated, that's simply not realistic

Originally Posted by Baph

For example (and rather a lot of assumptions, but since you require the theoretical "proof" behind the physical evidence), lets assume that the circuits are activated at the exact same instance, and the differences in manufacturing for the compressor and air chamber mean that a sound is emitted from each horn at the exact same instance. This would produce waves that are completely in phase with one another (again, assuming the horns are idenically manufactured).

i wouldn't be asking for a logical reason to support your assertion if your "evidence" wasn't flawed and based on completely unworkable science

Originally Posted by Baph

Now, to achieve exactly opposite phase of the horns, you need a 0.001 second delay for one of the horns to start emitting a sound (by your numbers). Of course, given the various manufacturing differences of the various components, this delay won't actually be 0.001 seconds, but we'll go with that for now.

so you're saying that because of manufacturing differences you can never achieve, or are at least highly unlikely to achieve exactly 180 degrees offset? no **** sherlock, i've been saying this all night

Originally Posted by Baph

Since I understand how a compressor works by pulsed charging, I can see that even a very minimal change to the activation time, can mean that an entire pulse is missed, but more than likely it was only approx half a valve cycle. Unfortunately the system we're describing isn't a simple matter of a small fan pushing air through a cone. Missing a whole pulse cycle in a small compressor like this can easily mean 1/8th or 1/4th a second delay on the output (as it's effectively an over-pressure safety valve).

so a quarter or eighth or a second vs a thousandth of a second between 0 and 180 degree in the waves, or to put it another way, in that time the horn has already missed over 100 cycles, there is a small chance it might land on exactly the right offset to be 180degree out of phase with the other horn, however it is practically zero, and would only be able to cancel out the other wave in a theoretical world, in reality, as i said before, the distances, the echos and other real world factors make it impossible to create that kind of silence. also, the two tones are never going to be exactly the same frequency, so even if you did manage to create the destructive interference they would not remain out of phase for very long

Originally Posted by Baph

Whilst I can't guarantee the above theory, I can guarantee that I can reproduce the effect physically.

not by only altering the length of the wire you won't

Originally Posted by Baph

Also, just for the record, the inspiration behind changing the length of wire came from an Acoustic Engineer. In fact, I believe I remember his words being to ensure the horns were turned simultaneously. So please, less of the accusations about lack of understanding.

hang on, you had to ask someone else and then say you understand it?, riiiiight


seriously, you really need to go and look up how interference works - even if you want to completely disregard all of the above, read the following paragraph carefully and understand it - if you do, you'll see why two m/c horns will never be able to create silence by destructive interference...

having two identical waves produced 180 degrees out of phase in two different locations doesn't just produce silence at all points around the sources, the magnitude of the wave at a point where you observe it depends on the distances from the observation point to the sources of both waves, and the relationship of those distances with the wavelength of the waves. there will be points where the magnitude of the resultant wave is zero, but there will also be places where constructive interference takes place and the resultant wave is twice as big as each source but the overwhelming majority of points will have some fraction of the original waves remaining, 100% complete destructive or constructive interference requires incredibly unlikely circumstances to occur. that's why the situation you think you experienced, where both horns are sounding yet you can't hear anything no matter where you place your head around the bike, is physically impossible

this website has a rough experiment demonstrating how interference works, it's describing quantum mechanical interference of electrons but the rope experiment demonstrates what i'm trying to get you to understand:
http://www.rodenburg.org/theory/y800.html

I make that approx 20mins for you to type all that. Well done. You say you're not taking things personally, but you're taking a lot longer than I am to write replies.

Originally Posted by the_lone_wolf

if you do, you'll see why two m/c horns will never be able to create silence by destructive interference...

That's funny, as apparently I've heard the impossible. What you say "will never happen" has happened, numerous times.

Since it's now 15mins until I leave, I'll share the golden nugget. I never claimed exactly out of phase (although realistically, this did happen most of the time - with the exception I'll explain in a second).

What actually happened was that probably 8/10 times pressing the button, there was no audio, and other times, very poor quality audio (for a bike horn). Now, you could argue that as I was only pressing the button for probably less than a second, the waves didn't have time to get back into a reasonable phase so that I could hear it. Therefore there has to be some form of "window" that the waves were starting (hence the exception to the above paragraph).

However, adjusting the length of the wire was the only adjustment made, and doing so made the horns 100% reliable.

Believe me, don't believe me, I'm not the only person to witness it.

Anyhow, time to pack up & ride home.

EDIT: Following the same conversation with the Acoustic Engineer, I have sucessfully setup horns on my bike that give the effect known as "frequency beats" - how I explain things rarely relates to my understanding of any given issue.

[the_lone_wolf]

Originally Posted by Baph

I make that approx 20mins for you to type all that. Well done. You say you're not taking things personally, but you're taking a lot longer than I am to write replies.

if you take your time and check what you type, you don't make stupid mistakes that make you seem like you have no clue what you're talking about...

anyways, in the aeon it's taken me to reply you're probably home so i might as well try once again to explain how interference works...

Originally Posted by Baph

That's funny, as apparently I've heard the impossible. What you say "will never happen" has happened, numerous times.

no, it didn't, see below

Originally Posted by Baph

Since it's now 15mins until I leave, I'll share the golden nugget. I never claimed exactly out of phase (although realistically, this did happen most of the time - with the exception I'll explain in a second).

no, it really didn't, see below

Originally Posted by Baph

What actually happened was that probably 8/10 times pressing the button, there was no audio, and other times, very poor quality audio (for a bike horn). Now, you could argue that as I was only pressing the button for probably less than a second, the waves didn't have time to get back into a reasonable phase so that I could hear it. Therefore there has to be some form of "window" that the waves were starting (hence the exception to the above paragraph).

you've managed to spectacularly miss the point of the only part of my last post that you should have paid attention to...

i'm not talking about time dependent phase shifts, frequency beats or anything like that, and without looking up how interference works for yourself you won't understand why what you're saying makes no sense whatsoever

----------------------------------------

try to visualise this situation:

you are standing in front of two speakers which are several metres apart mounted on a wall at head height. these are our sources, they are producing the same single tone of a constant wavelength and are completely in phase with each other

now imagine you're standing directly in front of the left speaker, you stand at precisely one wavelength back from the left speaker, which is also exactly 1.5 wavelengths from the right speaker. because the two waves you are hearing are now a half wavelength out of phase they will cancel each other out and you hear nothing. the situation is the same if you stand directly in front of the right speaker, one wavelength back.

now imagine you are standing facing the wall that the speakers are mounted on, positioned directly in front of the spot on the wall between the two speakers. now the paths from both the left and right speakers are the same length, so you get constructive interference and hear a wave with double the magnitude of what each speaker is producing

can you see how it's not only the location of the sound sources, and their phase relative to each other that defines the magnitude of the wave at a given point, the magnitude is also completely dependent on how far you are from each source.

you don't experience this in real life because the wavelengths of audible sound are usually much smaller than the distances they travel over, and the fact that you have two ears means that there are two points which would need to meet the unlikely criteria for destructive interference

----------------------------------------

Originally Posted by Baph

However, adjusting the length of the wire was the only adjustment made, and doing so made the horns 100% reliable.

it couldn't have been the only adjustment, because the horns were not producing any sound before you adjusted the wiring. if you understood interference you'd know why that has to be the case

Originally Posted by Baph

Believe me, don't believe me, I'm not the only person to witness it.

i don't doubt what you heard, but you have completely misunderstood what was causing what you heard

I fully understand the subject, and was essentially trolling last night. Apologies, but I get like that when bored. There was a reason I wasn't disputing the theory of sinusiodal interference. I did drop a few subtle hints, such as stating that I was watching how long you spent typing.

You have to acknowldge, since these are very short wavelenths, that there will be a very large number of positions (in terms of both distance, and angle or incidence from the point of origin).

In reality, because the motors started at different times (however small that difference was), the motor spin up will be delayed, and the compressor output delayed and the waves will be ever so slightly out of phase. Again, the delay starting the motor will be compounded by the way the compressor(s) work.

It might also be worth mentioning (before you start ranting again) that the horns both face vertically downwards, and I was above them. Therefore the majority of any audio reaching my ears would be deflected from the floor, which obviously affects the sound.

Unlikely criteria, yes, impossible, no. You did keep saying words to the effect of "it'll never happen."

As for the wire being not the only adjustment, believe me it was. You still haven't answered why both horns had current flowing through them, yet nothing was audiable. To me, that clearly demonstrates that the circuit was complete and functional.

Reply if you like, no doubt I'll be bored again later this afternoon.

Zzzzzzz