rec.autos.simulators

by **Jari Jokine** » Sat, 03 Apr 1999 04:00:00

Hi!
When I tried Patrick's replacement engine sounds for GPL,
I noticed, that they have different pitch from the originals.
So I did some experimenting and found that neither Patrick's
nor the original sounds have pitch, which matches with the
rpm in the game.

If you want to verify this, switch to chase view so you can
see rpm, switch to neutral and rev up to 6600. 6600 rpm is
110 Hz, which is the lowest "A" you can sing or the second
lowest string in guitar. If the engine sound was correctly in
tune, you would now hear 110 Hz and/or some of it's
multipliers. Another good rpm to try is 8810, which is
147 Hz = D = the third lowest string in guitar.

I found that some Papyrus sounds have 220 Hz at 6600 rpm,
but Patrick's Lotus/Eagle sound was closest to what I would
expect - only a bit too high.

Actually I am not quite sure about that multiplier thing. Engines
can produce both harmonic and inharmonic overtones. However,
I would wxpect some "musical" relationship between the rpm and
the engine sound.

Sorry about a bit pointless post. I have nothing better to do
today.

Jari Jokinen

by **Trip** » Sat, 03 Apr 1999 04:00:00

Also bear in mind that the number of cylinders will affect the note at
any given RPM... You can't just divide RPM by 60 and derive the pitch of
the exhaust sound.

Trips

> Hi!
> When I tried Patrick's replacement engine sounds for GPL,
> I noticed, that they have different pitch from the originals.
> So I did some experimenting and found that neither Patrick's
> nor the original sounds have pitch, which matches with the
> rpm in the game.

> If you want to verify this, switch to chase view so you can
> see rpm, switch to neutral and rev up to 6600. 6600 rpm is
> 110 Hz, which is the lowest "A" you can sing or the second
> lowest string in guitar. If the engine sound was correctly in
> tune, you would now hear 110 Hz and/or some of it's
> multipliers. Another good rpm to try is 8810, which is
> 147 Hz = D = the third lowest string in guitar.

> I found that some Papyrus sounds have 220 Hz at 6600 rpm,
> but Patrick's Lotus/Eagle sound was closest to what I would
> expect - only a bit too high.

> Actually I am not quite sure about that multiplier thing. Engines
> can produce both harmonic and inharmonic overtones. However,
> I would wxpect some "musical" relationship between the rpm and
> the engine sound.

> Sorry about a bit pointless post. I have nothing better to do
> today.

> Jari Jokinen

by **Trey Beh** » Sun, 04 Apr 1999 04:00:00

>Also bear in mind that the number of cylinders will affect the note at
>any given RPM...

As would the length of the exhaust system (manifold and headers) itself, as in
any wind instrument with a tone generator at one end?

Trey Behan

by **Wosc** » Sun, 04 Apr 1999 04:00:00

You even further must remember that you can change the sampling RPM from
inside the app text file so if you REALLY want the pitch to be perfect, just
change that number until it fits right and you have a perfectly tuned,
musically sound, engine.
hehehehe

Jesse

|
|>Also bear in mind that the number of cylinders will affect the note at
|>any given RPM...
|
|As would the length of the exhaust system (manifold and headers) itself, as
in
|any wind instrument with a tone generator at one end?
|
|Trey Behan

by **Jari Jokine** » Sun, 04 Apr 1999 04:00:00

I didn't know it was that easy! Anyway the tuned WAV files are now
posted at alt.binaries.autos.simulators for musically sensitive drivers
to try.

>You even further must remember that you can change the sampling RPM from
>inside the app text file so if you REALLY want the pitch to be perfect,
just
>change that number until it fits right and you have a perfectly tuned,
>musically sound, engine.
>hehehehe

>Jesse

by **Jari Jokine** » Mon, 05 Apr 1999 05:00:00

I have listened two Ferrari samples and there seems to be a very
strong component at frequency rpm x 4.5. That's 9th harmonic
for rpm divided by two and makes two octaves plus a major second
as a musical interval.

>Not true. These are 4 stroke engines. Each cylinder fires
>only once every two revolutions. Also, the pitch is definitely
>affected by numbers of cylinders and other factors. Compare
>the sound of a real-life Ferrari F1 and almost anything else
>at the same RPM....... :)

>--
>// rrevved posts from mindspring dot com

by **mjessick-Motorsim** » Sat, 10 Apr 1999 04:00:00

As an example of what is being discussed here,
I set up a web page with a chart showing the
"Power Spectral Density" of a Ducati motorcycle
sound recording.

The chart has the frequency scaled
by the RPM of the sample so you can easily see
just how much of the sound's power is concentrated
in the frequency ranges of half per rev, one per rev,
one and a half per rev, two per rev, etc.

http://www.motorsims.com/users/mjessick/sample_psd.htm

- Matt

> I have listened two Ferrari samples and there seems to be a very
> strong component at frequency rpm x 4.5. That's 9th harmonic
> for rpm divided by two and makes two octaves plus a major second
> as a musical interval.

> >Not true. These are 4 stroke engines. Each cylinder fires
> >only once every two revolutions. Also, the pitch is definitely
> >affected by numbers of cylinders and other factors. Compare
> >the sound of a real-life Ferrari F1 and almost anything else
> >at the same RPM....... :)

> >--
> >// rrevved posts from mindspring dot com

--
Matthew V. Jessick Motorsims

Vehicle Dynamics Engineer (972)910-8866, Fax: (972)910-8216

by **Jari Jokine** » Wed, 14 Apr 1999 04:00:00

That was interesting. The base frequency of engine tone should
thus be rpm divided by two. My ears tell me, that of Papyrus'
original sounds only Lotus and Eagle match this criteria. Brabham,
Murasama adn Coventry are a minor third too high. BRM is a
perfect fourth too low and Ferrari is a major third too low. The
Papyrus Ferrari has a *** harmonic at 10 x base frequency,
which can confuse the ear. It also sounds very bright, if transposed
upwards to the correct (?) pitch. A bit of filtration propably helps.

I will verify the frequencies, when I find a program, that can do
frequency analysis, but I am pretty sure of what I hear.

Jari Jokinen

>As an example of what is being discussed here,
>I set up a web page with a chart showing the
>"Power Spectral Density" of a Ducati motorcycle
>sound recording.

>The chart has the frequency scaled
>by the RPM of the sample so you can easily see
>just how much of the sound's power is concentrated
>in the frequency ranges of half per rev, one per rev,
>one and a half per rev, two per rev, etc.

>http://www.racesimcentral.net/

>- Matt

by **Mike Rodrigue** » Thu, 15 Apr 1999 04:00:00

As a user of your 'musical' engine sounds, I am looking forward to hearing
any developments from you guys.

Mikey

by **Jari Jokine** » Sat, 17 Apr 1999 04:00:00

I did just post some "new" engine sounds to alt.binaries.simulators.autos
and alt.binaries.misc. I think the engines play nicely together now :)

Jari Jokinen

>As a user of your 'musical' engine sounds, I am looking forward to hearing
>any developments from you guys.

>Mikey

rec.autos.simulators

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.

GPL: A "musical" note.