Showing posts with label is. Show all posts
Showing posts with label is. Show all posts

Thursday, October 23, 2014

Is Bigger Better in Auto Sound Systems

When it comes to auto sound systems, one question seems to be repeated often-is bigger better? The honest answer to that is not by a long shot. There are many excellent quality sound systems that will not require the backseat and your first-born in order to enjoy wonderful quality of sound and music as you drive along on your daily commute. One thing that is important to remember is that dynamite does in fact come in small packages. The same can be true of a good quality sound system for your car, truck, or SUV.

You can elect to have the full range sound package. This package, if not custom installed by the dealer can take up a great deal of real estate within your car, truck, or SUV. If you own a compact car, these types of speakers and this particular type of sound system is definitely not recommended. The first reason it is unattractive is that it will most likely require either the vast majority of your trunk or take out your back seat. I for one like being able to cart around friends, relatives, and/or children-my back seat isnt up for grabs. I also prefer the continuity of a factory-installed system that takes up none of the premium living space within the interior of my SUV.

I am personally biased towards the wonderful sound quality of the Bose sound system and speakers. The quality of sound with this particular system is excellent and any true music lover will tell you that good quality of sound is better by far than a louder sound. This is not to say that the Bose sound system will be the perfect choice for everyone to use as his or her auto sound system only that it is my first choice as a music lover.

I prefer a softer sound that has good quality to a louder sound of the substandard or even average quality on any day. The problem with most big sound systems and speakers is that they often sound hollow or tinny rather than full and robust. A good auto sound system will provide the best possible sound within the confines of the least possible space. You will probably find that you dont need to sacrifice your backseat in order to hold the speakers and while the Bose sound system for automobiles does cost more than some sound systems, it wont require a second mortgage on your home in order to afford. There are actually times in life when you get what you pay for.

The important thing to remember is that you do not have to have the most expensive, the best known, or even the biggest sound system in order to have a wonderful quality sound system in your automobile. You will not even have to have a Bose sound system in order to have a sound system that is not only excellent quality but also excellent sound. You do not need to pay an arm and a leg or any other appendages in order to have a good sound on your daily commute to work.

Music is all around us, at work, at home, on television shows. Music sets moods, sets tones, and kills moods on occasion. It only makes sense that you have good quality equipment upon which to play the music that so greatly enhances and enriches your life. If you are in the market for an auto sound system it only makes sense to listen to several before deciding on the one that will work best with your musical tastes and your desire for your vehicle sound system. Dont be misled by commission minded sales associated that think you need the latest, greatest, and most expensive toy on the market. Find a system that sounds good to you and go with that system. You do not have to go for a better sound if you find a sound you like that should be enough.
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Friday, October 17, 2014

What is CMOS Digital Electronics Technology C MOS

C-MOS or CMOS stands for complementary metal-oxide-semiconductor, it is a technology for constructing integrated circuits widely used in microprocessors, microcontrollers, and other Digital Memory RAM circuits. CMOS technology is also used for several analog circuits such as image sensors, data converters and transceivers for many types of communication. Created by Frank Wanlassem 1963, CMOS is also sometimes referred to as complementary-symmetry metal-oxide-c or COS-MOS semiconductor. The words "complementary-symmetry" refer to the fact that the typical digital design style with CMOS uses complementary and symmetrical pairs of field effect transistors (Field Effect Transistors - FET) p-type or n semiconductor oxide metal (MOSFETs) for logic functions, as shown in figure below.



What is CMOS

Existem features relevant and important in CMOS devices such as low immunity to static and low energy consumption. As one of the transistor pair is always turned off, the combinação em series consumes significant energy only momentarily during the alternation between connected and disconnected states (on / off). Consequentemente, CMOS devices NON produzem much heat as other forms of rationale, such as TTL, which typically consume current even quando em home.

The também CMOS technology enables high-density u funções em um logic single chip. It was mainly for this race that has become the most used technology to be applied em VLSI (Very-large-scale Integration), is the Process of criação integrated circuit through the combinação of milhares transistor em um single chip.

Family CMOS integrated circuits - 4000 and 74C

The 4000 series is a family of CMOS integrated circuits that implement a variety of logic functions that are still in use today . They were introduced by RCA as CD4000 series COS / MOS in the year 1968 as a lower power and a more versatile alternative to the 7400 series TTL . This CMOS series have the advantage of lower power consumption and wide range of supply voltages of 3 V to 15 V . However its speed is slower , 1 MHz , compared to the 10 MHz bipolar TTL , this limits their applications to projects of low speed or static .

Characteristics CMOS

Supply ( Vdd ) : as the supply voltage , this family allows for series 4000 and 74C operating in the range of 3V to 15V , for the HC version of 2V to 6V and HCT of 4.5 V to 5.5 V. For series low voltage , the range is from 1V to 3.6V and 1.2V to LV to 3.3 V , typical voltage of various current systems .

Integrated circuits CMOS Whenever there unused entries or entire unused ports , it is critical that all inputs are grounded or connected to + VDC , we have to take this step due to
large impedance inputs 10 ¹ ² Ω , and any stray current or arising from noise in the input lead to a considerable increase of tension.

The CMOS sub-families are in the table below.

HC - High Speed ​​CMOS - CMOS High Speed
HCT - High Speed ​​CMOS with TTL inputs - High Speed ​​CMOS with TTL inputs
AC - Advanced CMOS - CMOS Advanced High-speed version
ACT - Advanced CMOS with TTL inputs - Advanced CMOS inputs with TTL-version
BCT - BiCMOS Technology - Technology BiCMOS (Bipolar / CMOS)
ABT - Advanced BiCMOS Technology - Advanced BiCMOS Technology
LVT - Low Voltage Technology - Technology Low Voltage

New CMOS technology

New manufacturing technologies largely overcame the speed problems , while maintaining compatibility with most circuit designs . Although all semiconductors can be damaged by electrostatic discharge , high impedance CMOS inputs makes them more susceptible than bipolar transistors based , TTL . Eventually , the advantages of CMOS (especially the later series such as 74HC ) (High- speed CMOS ) surpassed the older TTL chips . The 4000 series is still widely available , but perhaps less important than it was two decades ago .

The 4000 series was expanded in the late 1970s and 1980s to include new functions , or were better versions , most of these newer chips were given the 4500 series, but are still considered by engineers as part of the series of 4000 . During the 1990s , some manufacturers such as Texas Instruments , merged its online its latest technology called HCMOS emerging devices like 74HCT4060 , having the same features of a 4060 but with greater speed.

CMOS integrated circuit

Lets take the example of 4011, an integrated circuit CMOS 4000 series, which contains four independent NAND gates of two inputs. The pinout see below. This chip is different in pinout to the TTL 7400, but it can fulfill its function if done modifications pins.


In 4011 pinout can see that the 7 pin is the negative supply and the 14 pin is the positive supply.
Since pins 1 and 2, 5, 6, 8, 9, 12 and 13 are input ports and pins 3, 4, 10, 11 are output ports. To get a better idea the image below shows the relationship without taking into account the position of the pins on the chip.


The truth table is a mathematical table that logic, it consists of a column for each variable (A and B in our case only two inputs) input, and a final column for all possible outcomes of the logic operation, output or output and in our case Q. Each row of the truth table contains one possible configuration of the input variables, and the result of the operation of such values​​.

H = HIGH = 1 high = 5 Volts
L = LOW = 0 = 0 = Low Volts

The truth table for the four doors 4011 is shown below.

A     B         Q
0     0         1
0     1         1
1     0         1
1     1         0

Advantages and disadvantages of CMOS integrated circuits

In comparison with other digital technologies and CMOS logic families have advantages and disadvantages, see below major.

Advantages

manufacturing is simpler and less costly;
does not use resistors;
has a high input impedance;

Disadvantages

fragility static electricity
delay time;
low-speed operation;

Other members of logic families:

RTL - resistor-transistor logic - Obsolete Technology
DTL - Diode-Transistor Logic - Obsolete Technology
DCTL - Transistor Logic Direct coupling
TTL - Transistor-Transistor Logic
ECL - Emitter-coupled logic
MOS - Metal Oxide Semiconductor:
PMOS - Logic of p-channel MOSFETs - Obsolete Technology
NMOS - Logic n-channel MOSFETs
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Sunday, August 31, 2014

A Good Auto Sound System is a Requirement not a Luxury

How do you decide which auto sound system is best for you? This is a question that many consumers ask in the U. S. each and every day. The truth is that only you can decide what kind of sound you find enjoyable and what you are seeking in the sound system you will ultimately purchase. A good sound system will greatly improve how you feel about not only the vehicle you drive but also your disposition after your daily commute. It may seem like such a small thing, the changing of a sound system, but it does seem to have such a profound impact on how we start our days. Of course we all know that getting your day off to a good start sets the tone for the entire day and if that day is Monday it sets the tone for not only the day ahead but also the week to come.


Music affects almost every aspect of our lives. Most of us do not realize the impact that music has on our day-to-day lives and it is quite difficult because our world seems to be filled with it. It is much easier however, to explain the difference a good sound system makes. Its funny, I find myself in a hurry to get out of stores that have lousy sound systems and speakers that dribble out little more than static while I can shop for hours in a store that has tasteful music playing in the background over a good sound system. I prefer the volume lower and the music playing in the background rather than being the center of my attention.

Most of us find that soft music playing in the background is rather unobtrusive and allows us to get along with our thoughts and the mission at hand while loud music blaring over antiquated speakers does a great deal to disrupt our thought processes which will only serve to send us along to the next errand on our list. If youll notice it seems that clerks in the stores where the loud music blares along are often not as even tempered as those in stores that play music at respectful volumes and have very well kept sound systems. I think I would be cranky too after listening to music in a manner that music wasnt meant to be heard.

Im not a music snob by any means; I simply enjoy listening to music for the sake of actually hearing the music. Loud music is good sometimes but not when I have other things on my mind. I prefer that music remain in the background when Im running about taking care of errands, even in the car. The hallmark of a good auto sound system is that it sounds good even at low volumes. This means you can enjoy music in the background, hum along, or simply ignore the music in favor of the action taking place on the road.

The point Im trying to make is that even though you may not realize the impact that a good auto sound system has on music immediately, you will definitely feel the difference it makes over time. The better the sound system, the better the sound and music is after all, sound.

If you are a true lover of music and spend a great deal of your week or even any given day in your vehicle, doesnt it make sense to invest heavily in your auto sound system? I know for me that particular decision is a no brainer. I love music and it is an important part of not only my life but also the lives of my children. As a result we spend a lot of time listening to the radio in our SUV and singing along. Even when we arent listening to music, I enjoy listening talk radio and the news on NPR. These things are an important part of my day and I really enjoy all that each and every one adds to my life. Because of that, I find my investment in a good auto sound system to be a requirement rather than a luxury.

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Friday, August 29, 2014

What Is Sound

Sound?
Websters dictionary defines sound as:

"The perceived object occasioned by the impulse or vibration of a material substance affecting the ear; a sensation or perception of the mind received through the ear, and produced by the impulse or vibration of the air or other medium with which the ear is in contact; the effect of an impression made on the organs of hearing by an impulse or vibration of the air caused by a collision of bodies, or by other means; noise; report; as, the sound of a drum; the sound of the human voice; a horrid sound; a charming sound; a sharp, high, or shrill sound."

Mmm, fancy. We all know what a sound is. Its a noise, something we sense with our ears. But what is sound? Its the vibration of the air by a moving body. For our purposes in car audio that moving body is our speakers. The movement of the speaker forward and backward causes a vibration in the air that our ear receives and we hear music. Heres what sound looks like as a wave:



 
A sound wave goes through a cycle of 360 degrees. As the speaker moves forward it goes from rest (0 degrees) through one quarter of its cycle to 90 degrees. As it starts to move back to rest it travels another 90 degrees to the 180 degree mark before moving completely rearward to 270 degrees. As it moves back to the rest position it travels the final 90 degrees to the 360 degree mark. The cycle then repeats itself and we hear the result as music. To summarize, as the speaker moves up and down it travels one cycle which equals 360 degrees. These cycles are measured in Hertz (Hz) with one Hertz being equal to one cycle. The lower the number of Hz the lower the sound we hear. A human can hear, on average, the sounds between 20 Hz and 20,000 Hz (also known as 20 kHz).

We do not hear all of the sounds equally though. Our ears are less sensitive to sounds at the far ends of the scale. This was discovered through research done by Fletcher and Munson and they have given us the "Fletcher-Munson" curve which illustrates this point.



Notice how the curve goes up at both ends of the scale. Also notice how the curve is greater at lower volume levels (sound pressure levels). This is what the loudness circuit on a head unit tries to do. Increase the level of the low and high frequencies at lower volume levels. As the volume goes up the level of boost at these frequencies is reduced. However, some loudness circuits do nothing more than boost the low and high frequencies by a constant amount. If youve seen a vehicle with an in-dash equalizer the chances are very good that the vertical sliders were arranged in a similar fashion to the Fletcher-Munson curve. This is sometimes called "making your EQ smile".
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