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Discovering quirks in MATLAB, finding a simple noise filter, and getting great sound!

Creating the distortion

As we discovered in Problems with Distortion , when we work with the modified power series, we do not get the expected result. In fact, we onlyget a lower quality version of our original sound file! However, taking a look at the minimum and maximum of our soundvector, we soon discover the problem: all values of our signal are between 1 and -1! When we take these numbers to the tenpower, or even the five power, all we do is make our sound values smaller. Therefore, a quick fix would be to take thesenumbers to the one-tenth power or the one-fifth power, in effect dividing each power by ten. Upon checking out our signal, we get thewonderful distortion that we needed! As we play around with different coefficients and powers (all less than one), our owndiscerning ears determine which coefficients and powers are best for the distortion we want. However, in all of thisplaying around, a particular evil has crept in among our distortion: noise!

Dealing with the noise

Several different methods can be used to take out the noise from our signal. In fact, an entire project was dedicated to noise-elimination in 2002. However, since this project focuses mainly on a MATLABapproach rather than a C approach, we'll leave implimenting that noise filter to a more adventurous group.

The simplest way to get rid of the noise would be to impliment a band pass filter in MATLAB, allowing only for the frequencyrange of the guitar (about 100Hz to about 4000Hz, perhaps higher depending on the high notes you play). This filterwill get rid of most of the noise, except for the noise that lies within those frequencies.

Another easy way to get rid of the noise involves the FFT. After taking the FFT of the signal, you can decrease noise bythrowing out the frequencies below a certain threshold.

Questions & Answers

What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Ece 301 projects fall 2003. OpenStax CNX. Jan 22, 2004 Download for free at http://cnx.org/content/col10223/1.5
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