Enhancement Of Performance Parameters Of An Mp3 Player

International Journal of Engineering Research & Technology (IJERT)
ISSN: 2278-0181
Vol. 2 Issue 4, April - 2013
Enhancement Of Performance Parameters Of An Mp3 Player.
Azhar Syed, Monica Chauhan, Sylvester Dias.
Under the guidance of Prof. K. G Sawarkar.
There are many fine music players available from
the likes of Sony, Samsung, Apple, Creative and
Panasonic. However, it is often observed that the
best players in the market are exorbitantly priced all
because of the brand name of the manufacturers.
Also, these music players are still lacking in many
performance parameters which can be significantly
improved. The performance parameters are
expandable memory, frequency response, driver
software requirement, Bluetooth capability, output
power, signal processing abilities and most
importantly, cost. A portable mp3 player has been
developed which addresses the above mentioned
shortcomings in today’s music players. We have
first designed our own prototype, included and
improved existing features, added fine touches of
our own and also conducted a comparative study on
its performance compared to well establish products.
We also hope to debunk the myth that only the best
manufacturers can provide the best technology.
This paper demonstrates the maximization of results
and features using minimum essentials. We would
also like to demonstrate the possibility of designing
and executing a standalone electronics device at the
graduate level, which was our main motivation. As
a result of our work, we have met most of the
objectives that we have initially set out to achieve
and also found out innovative workarounds to
certain problems that were encountered. We are
proud to present the AMS mp3 player- a music
player for an enhanced experience.
people approach music.” And rightly so, but even an
iPod has shortcomings. There are many features that
are still missing from an iPod or for that matter many
of the leading music players that are currently
available. One might think that with the constant
innovation and new technologies on display that the
portable music player industry has reached its zenith
in terms of innovation and only something new and
revolutionary can set of a spark just like the iPod did
more than a decade ago. However, there is so much
that is still lacking in today’s mp3 players that leave a
lot to be desired. This technical paper is the result of
actual implementation of our own mp3 player and
most importantly enhancing its performance
The performance parameters are expandable
memory, driver software, frequency response, output
power and signal processing. After conducting an
extensive literature survey, we found no portable
music player supports expandable memory. Most of
these players have fixed memory and higher the
memory capacity, greater is the cost. Also, almost all
music players require driver software installed in a
PC to transfer music to the player. Users face many
issues related to usage of driver software from
compatibility to faulty functionality. It’s a wonder
that most manufacturers haven’t done away with the
use of driver software. Apart from these, quality is
mostly associated by brand name and not by actual
measurable parameters. So, even the best mp3
players have some shortcomings when it comes to
providing the best sound quality.
The goal of this project is to address these
shortcomings and enhance the above mentioned
performance parameters. We also back up our work
with a comparative study with available portable mp3
players. During the course of the implementation of
this project, we have not only learned to make a
device comparable to market standards but also
realized that hardly anyone has conducted research in
this area. The leading products and their
manufacturers have hardly been challenged, nor has
there been any study addressing shortcomings in the
An Apple iPod or a Samsung or Sony mp3
player may be widely considered as the best portable
music player around in the market. According to Karl
Lagerfeld “The iPod completely changed the way
International Journal of Engineering Research & Technology (IJERT)
ISSN: 2278-0181
Vol. 2 Issue 4, April - 2013
product. This project aims to identify chinks in the
armor of commercial mp3 players and to match or
even better them at graduate engineering level. Also,
most importantly to achieve all this without
compromising on a low-cost requirement to compete
with the price war in today’s markets.
current song, the volume bar and the current state of
playback is displayed on the screen
Results and Discussions.
Now that our working model was complete, we set
out to do an analysis on its output.
Work Done.
A white noise mp3 file was taken which had almost
flat frequency response characteristics from 0 to 10
KHz after which the characteristics tapered off to a
lower level. The tests were conducted with the same
mp3 file at maximum volume of respective devices.
The output was analyzed by calculating the FFT
using Blackman window taking 16376 points. The
obtained characteristics were very much close to flat
except for a slight peak at 200 Hz. The test was then
conducted on an ordinary mobile phone an iPod nano
and Samsung galaxy S duos Smartphone; sharp peaks
were observed in higher frequency ranges indicating
that even the leading manufacturers are not able to
reproduce perfect frequency response. Also our result
revealed significantly higher power or voltage
compared to all the other music players.
The first Objective was to make a working, basic
mp3 player with memory card slot, as the memory
element for storing audio files. The components used
are Arduino Mega Board, VS 1053b mp3 decoder
chip and PCD8544 graphics LCD display. Arduino
Mega Board contains an At Mega 2560
microcontroller IC which runs on a 16 MHz
oscillator. It has 6 hardware interrupts and 6 internal
times. It is capable of SPI mode of communication
which is preferred mode of communication between
the Arduino and the peripheral chips. VS1053b is a
powerful digital signal processing IC which is
capable of decoding streamed digital mp3 files into
analog form and amplifying it sufficiently for
headphones or small speaker output PCD8544 is a
graphics LCD display which was used in the older
model Nokia phones
The use of Arduino & its IDE made the software
aspect quite easy. The libraries and online resources
helped in the overall writing of code. The major
aspect of code was interfacing the SD card with the
Arduino Board. The SD Fat library was the main
resource. However a detailed study of this library and
underlying SD card technology was done and hence
we successfully interfaced the SD card with the
Arduino. Now that audio files from the memory card
were easy to access, data was read from the audio file
and streamed serially to the decoder chip. The
datasheet of the VS1053b chip was highly
informative and clear instructions were provided in
its use. In this manner we were able to make the basic
working prototype and in the process achieved our
first objective of making a Mp3 player with an
expandable memory slot. Now that we had achieved
basic playback, we set out for the next objective i.e
making the device driver software independent. It
was required to improve the robustness of code for
this purpose. After much manipulation and re-study
of Sd Fat library, driver software independency was
achieved. After this, the difficult task of interfacing
the display was achieved, displaying the name of the
White Noise Test.
Expandable Memory.
The next important feature is the expandable memory.
In our working prototype, as long as the file system is
FAT 16 or FAT 32 and there are mp3 files in the SD
card, it will play music. Hence, one can carry more
than a single SD card and switch it without any
hassle; also usage of expandable memory eliminates
the need of driver software. A card reader can be
used to directly copy the music files into the card.
The significance of expandable memory is that no
portable music player has this feature; the reason for
this is that, leading manufacturers have fixed memory
music players and price is directly proportional to
memory capacity. This puts the consumers at the
mercy of these brands and prices are exorbitant. The
price of our own prototype will reduce in comparison
Open Source
Our mp3 player will be an open source player, it will
be first of its kind, wherein the consumers will be
able to work on the code and hardware and come up
with their own suggestions and ideas regarding the
International Journal of Engineering Research & Technology (IJERT)
ISSN: 2278-0181
Vol. 2 Issue 4, April - 2013
Figure 1: White Noise Test Performed on AMS Mp3 Player.
The encircled region shows that when AMS mp3 player is tested with white noise, there is a slight peak at 200Hz,
this rise is of approximately +5dB and a fluctuation of +5db/-5dB under white noise test is acceptable.
Figure 2: White Noise Test Performed on Ordinary Phone.
An ordinary phone was tested with white noise and the above figure illustrates a deviation from proper
characteristics at higher frequencies. Higher frequencies are unnecessarily amplified.
International Journal of Engineering Research & Technology (IJERT)
ISSN: 2278-0181
Vol. 2 Issue 4, April - 2013
Figure 3: White Noise Test Performed on Samsung Galaxy S Duos.
The Samsung Galaxy S Duos smart phone was tested with white noise and it was seen that, there were sharp peaks
at higher frequencies, the sharp peaks at higher frequencies is shown by the encircled region in the above figure .
Figure 4: White Noise Test Performed on iPod Nano.
The white noise test was performed on Apple iPod Nano and it was seen that there were sharp peaks at higher
frequencies (as shown in the figure above)
International Journal of Engineering Research & Technology (IJERT)
ISSN: 2278-0181
Vol. 2 Issue 4, April - 2013
Figure 5: Output Power AMS mp3 Player.
Figure 6: Output Power of iPhone 5
The above figures show the comparison between the out power of AMS mp3 player and iPhone 5. It can be seen that
the peak to peak value for AMS is much higher than iPhone 5.
(This test was performed for a white noise file under identical conditions for both players at their maximum
Hardware Comparisons.
This is a head-to-head hardware comparison of an iPod classic with our own AMS player.
Table 1: Comparison
Audio Chip
iPod Classic
30 GB Toshiba 1.8 inch hard drive
2.5 inch TFT LCD
Two ARM 7TDMI-derived CPUs running
Wolfson Microelectronics WM8752 codec
As seen from this comparison, the hardware used by
our prototype is quite inferior as far as CPU and
display is concerned. Yet, we have almost
comparable results. And as far as memory is
concerned, removable and expandable memories
have a hands-down advantage over fixed hard drives.
The audio chips used by both are more or less
comparable and hence not much difference in sound
output is found. It is fascinating to see that we have
made an mp3 player with a single CPU running at
more than 5 times lesser speed than that on an iPod.
This shows that with an improvement in hardware,
even more multitasking can be achieved for an even
better device.
AMS Mp3 Player
Removable SD card (up to 64 GB)
PCD8544 Graphic LCD
AtMega 2560 running at 16 MHz
SPI Mode.
Another important feature is the method of access of
SD card. In this we are handicapped by the usage of
slower SPI mode [1]. Serial Data Interface (SDI)
mode provides a faster access of data in SD card.
However its use is licensed and needs to be
purchased on a yearly basis. However, no problem
with playback was found at any time in our player.
During the implementation, we came across a
peculiar problem; usually hardware interrupts are
used to interface external buttons to a microcontroller. However in our case, we had many
buttons and fewer external hardware interrupt pins; as
a workaround we connected these buttons to normal
International Journal of Engineering Research & Technology (IJERT)
ISSN: 2278-0181
Vol. 2 Issue 4, April - 2013
digital pins, just as an interrupt pin is internally
continuously polled, these digital pins were also
continuously polled using timer interrupts. When the
internal time, which is pre-scaled to a predefined
value, overflows and generates an interrupt. In the
ISR (Interrupt Service Routine), we used polling
technique at digital pins to check if a button has been
pressed, if yes then a variable is initialized. We had
to take care that any event of a button being pressed
is not missed, and neither the button should be
pressed so fast that it registers twice. In such a
scenario continuous poling becomes difficult, also
another matter of switch debouncing had to be taken
into consideration. So for the button interface board
we connected the output of the buttons to a RC
circuit which smoothens out the switch debounce and
this output was converted into a square wave by
inverting Schmitt trigger. The use of RC circuits in
the buttons interface board meant that we had to
calculate the time constant of charging and
discharging so that we could adjust best possible time
lag between two presses of a button.
Important Results.
The AMS mp3 player has an expandable
memory slot up to 64 GB, which is more
than the maximum fixed capacity provided
by the leading manufacturers.
The AMS mp3 player requires no driver
software, where as the leading mp3 players
in the market require a driver software
(iPod’s require iTunes).
The AMS player has a better frequency
response in comparison to some of the
leading mp3 players manufactured today.
The AMS mp3 player has better output
power in comparison to the output power of
iPhone 5, which is well known for its output
The AMS mp3 player is an open source mp3
player, first of its kind as none of the leading
mp3 players are open source
The AMS mp3 player requires minimum
essentials in comparison to the leading mp3
players manufactured today, due to which
the overall cost of the player is low.
The AMS mp3 player has made use SPI
mode instead of SDI mode and is capable of
performing the same functions comfortably.
Portable music players are constantly
evolving as technology evolves. Since music forms
an integral part of the society, constant effort is being
made to make a more enjoyable, interactive and
visceral experience. However, in this bid to keep
adding to the new features, there is still a lot of
simple fixes that can be employed in the current
marketed products to benefit the user.
As explained in this paper, a successful
attempt has been made to enhance certain parameters
of portable mp3 players. As far as music and audio
quality is concerned, our results have shown that we
are able to match and even better the audio quality
provided by leading brands. When it comes to
usability, our device -which does not need driver
software-, comes up trumps against the competition.
Expandable memory and removable SD card slot
gives an added advantage fixed memory devices and
it will liberate the consumers from the need to pay
more for higher memory capacities.
We would like to conclude by saying that
even though one might hardly consider there being
any scope for improvement in portable music player,
we have identified and enhanced it in certain aspects.
Also, the fact that we were able to make a superior
device at graduate engineering level, will help in
debunking the myth that only leading brands produce
best quality products. This will not only empower
young entrepreneurs but also promote research at
graduate engineering level to challenge established
We would like to thank our guide, Professor K.G
Sawarkar , who helped us throughout the making of
our project, his guidance was very important for us in
achieving our goals and completing our project and
[1] Dhananjay V. Gadre, “Programming and Customizing
the AVR Microcontroller” McGraw Hill, 2000 Indian
Reprint Edition
[2] Martin Ruckert,”Understanding Mp3-Syntax,Semantics
and Algorithms” GWV Vieweg Publications 01 May 2005.