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Synthesizing Engine Sounds

Started by Tim Wescott July 30, 2013
Den tirsdag den 6. august 2013 19.59.48 UTC+2 skrev Eric Jacobsen:
> On Tue, 06 Aug 2013 12:28:13 -0500, "DougB" <60916@dsprelated> wrote: > > > > >>On 7/30/13 3:10 PM, Tim Wescott wrote: > > >>> > > >>> It's for making an electric-powered airplane sound like it has a heavy- > > >>> metal radial engine. > > > > > >Let me know if you ever figure that out. I'm sure the model airplane > > >industry would love to know as well. > > > > > >Personally I think it's a crime to put and electric motor on a scale > > >airplane. You not only want it to look real - it's got to sound real as > > >well. I don't understand how someone can spend time building a scale > > >aircraft and put an electric motor on it - you go to take off and all you > > >hear is some high-pitched whine, which makes it sound like some Walmart > > >toy. > > > > Most of the model engines don't sound particularly real, either, > > especially the 2-strokes. Hard to make anything with less than 12 > > cylinders sound like a Merlin. >
well I'd think 27 liters has a bit to do with it too ;) it "only" does something like 3000rpm when pushed -Lasse
On Tue, 06 Aug 2013 13:04:16 -0500, Tim Wescott
<tim@seemywebsite.really> wrote:

>On Tue, 06 Aug 2013 12:28:13 -0500, DougB wrote: > >>>On 7/30/13 3:10 PM, Tim Wescott wrote: >>>> >>>> It's for making an electric-powered airplane sound like it has a >>>> heavy- >>>> metal radial engine. >> >> Let me know if you ever figure that out. I'm sure the model airplane >> industry would love to know as well. >> >> Personally I think it's a crime to put and electric motor on a scale >> airplane. You not only want it to look real - it's got to sound real as >> well. I don't understand how someone can spend time building a scale >> aircraft and put an electric motor on it - you go to take off and all >> you hear is some high-pitched whine, which makes it sound like some >> Walmart toy. > >To make it sound realistic in flight would pretty much require a >loudspeaker on the plane. I seem to recall seeing something like that in >Flying Models. > >I just want something that'll raise eyebrows in the pits when I start my >motor.
Hi Tim, Check this out: http://xkcd.com/560/ [-Rick-]
Or how about like this:

http://www.youtube.com/watch?v=n17B_uFF4cA

:D

Tim Wescott wrote:

> On Tue, 06 Aug 2013 12:28:13 -0500, DougB wrote: > > >>On 7/30/13 3:10 PM, Tim Wescott wrote: > >>> > >>> It's for making an electric-powered airplane sound like it has a > >>> heavy- > >>> metal radial engine. > > > > Let me know if you ever figure that out. I'm sure the model airplane > > industry would love to know as well. > > > > Personally I think it's a crime to put and electric motor on a scale > > airplane. You not only want it to look real - it's got to sound real as > > well. I don't understand how someone can spend time building a scale > > aircraft and put an electric motor on it - you go to take off and all > > you hear is some high-pitched whine, which makes it sound like some > > Walmart toy. > > To make it sound realistic in flight would pretty much require a > loudspeaker on the plane. I seem to recall seeing something like that in > Flying Models. > > I just want something that'll raise eyebrows in the pits when I start my > motor.
In my dim deep student past I spent a summer in the arctic flying an WW II era PBY Catalina. There is nothing so heart stopping as an idling radial from the inside, clanking of free falling valve push rods, pops and bangs of unburned fuel from the lower cylinders being detonated in the exhaust system. (lower plugs often foul from oil leakage past the piston) But when it counts on a takeoff run it argues with you barking and misfiring as the the throttle is advanced, resigning as the last of the un burned fuel in the exhaust system explodes and it sees it your way. All of the rattles gets substituted for an co-ordinated roar and off you go. One pilot/mechanic friend described an idling radial engine as tool box full of random bolts and wrenches on a shake table. w..

langwadt@fonz.dk wrote:

> Den tirsdag den 6. august 2013 19.59.48 UTC+2 skrev Eric Jacobsen: > > On Tue, 06 Aug 2013 12:28:13 -0500, "DougB" <60916@dsprelated> wrote: > > > > > > > > >>On 7/30/13 3:10 PM, Tim Wescott wrote: > > > > >>> > > > > >>> It's for making an electric-powered airplane sound like it has a heavy- > > > > >>> metal radial engine. > > > > > > > > > >Let me know if you ever figure that out. I'm sure the model airplane > > > > >industry would love to know as well. > > > > > > > > > >Personally I think it's a crime to put and electric motor on a scale > > > > >airplane. You not only want it to look real - it's got to sound real as > > > > >well. I don't understand how someone can spend time building a scale > > > > >aircraft and put an electric motor on it - you go to take off and all you > > > > >hear is some high-pitched whine, which makes it sound like some Walmart > > > > >toy. > > > > > > > > Most of the model engines don't sound particularly real, either, > > > > especially the 2-strokes. Hard to make anything with less than 12 > > > > cylinders sound like a Merlin. > > > > well I'd think 27 liters has a bit to do with it too ;) > it "only" does something like 3000rpm when pushed >
A Merlin start is very different from a radial start. A radial is almost like a short march of single cylinder engines. A Merlin transitions from stopped to running starting with individual puffs of exhaust smoke and at some point you just don't hear the starter noise anymore, like bringing a swiss watch up to speed. The few times I have seen this happen up close was nothing short of awe inspiring w..