Posted by Sylvia Else on June 18, 2009, 12:40 am
Trevor Wilson wrote:
There are (or were) some particularly annoying car alarm systems,
installed primarily by people who were totally up themselves, which
produced a long sequence of sounds. They were certainly loud.
Look back at where this discussion started. The issue is whether
intending owners of Porsche and Ferrari vehicles who would dislike the
silence of an electric vehicle could be placated by replicating the
noise of the engine driven vehicles through loadspeakers.
It is less than clear whether the resulting sound would have to be as
loud as the original. Indeed, it might be sufficient to play the sound
inside the cabin. Depends on the psychology of those who value the noise
that the cars make.
So there are too many unanswered issues for it to be possible to arrive
at any concluded view that it's not feasible.
Posted by Trevor Wilson on June 18, 2009, 12:50 am
**Over a VERY restricted frequency range. They use a horn loudspeaker and
square waves (lots of harmonics) to acheive the result. Again: Nothing new
here. 1920s technology, driven by 1960s electronics. Again, for low
frequencies, horns need to be big. VERY big. It's just physics. You either
need a horn, or lots of power. Whichever way you slice it, it's gonna be a
**The owners of such vehicles almost always want to make themselves known to
all and sundry. Witness the present craze for turbo drivers who lift their
foot off the accelerator prematurely, in order to trip the waste gate. The
ONLY thing they do is make that waste gate noise. Many people with certain
types of vehicles like their vehicles to make specific noises to draw
attention to themrselves. Yes, I know: I don't understand it either.
**Certainly IF cabin noise is all that is required, then that is simple
enough to achieve. However, I doubt that is the aim.
**I'm still waiting for this new technology you refer to. What type of
transducer are you proposing? Or are you assuming that the thousands of
engineers, who have been working for the last 9 decades on the problem have
no idea? Are you attempting to re-write the laws of physics? Or are you just
speculating that something MUST be available, just because it seems like a
Posted by Knobdoodle on June 19, 2009, 10:24 am
They sound quite different when heard "free to air" and they sound equally
quite different when heard though a common-or-garden sound system.
Posted by Trevor Wilson on June 19, 2009, 9:55 pm
**You just made my point. The human ear is quite sensitive to various sonic
artefacts. So much so, that to design a mobile sound system, which can
reasonably accurately portray the sound of a particular automobile (engine),
such that people could be fooled into thinking that they were listening to
that engine, would be a massive undertaking. It would certainly NOT be
possible to (say) duplicate the sound of a 5 Litre V8 engine in a sound
system that can fit in a (say) Mazda MX5. At least not with the technology
available today and for the forseeable future.
Posted by Was Istoben on June 20, 2009, 1:15 am
I've heard Harley's that sounded like Harley's through itty bitty el-cheap
speaker in my TV.