THE VOODOO WORLD OF EQUALIZER (EQ)

How many of us get confuse, I mean really confuse in attempt to use the EQ to improve the vocal and may be, if you are lucky, to make it sound professional? By simply adjusting the EQ without knowing its outcome is not a good idea. You may end up getting the vocal too much EQ, which make it, sound terrible and may even cause feedback.

In this article, I shall be touching the basic concept of equalization and how it may affect the vocal as well as the music. How does EQ affect the sound? How do we make use of EQ to alter the sounds? Is EQ necessary for vocal and music? Why do things sound muddy? Why are some vocal sound blurred? Having difficulty to understand what the person is saying? These are the few question that we normally hear in regards to P.A. system or sound reinforcement system. Hope it will bring some light to the voodoo world of EQ.

Vocals
The vocal spectrum falls into three main frequency bands corresponding to the speech components known as:
Fundamentals:
a) Fundamentals: Speech fundamentals normally have a bandwidth between about 125Hz to 250Hz. To understand this range is important if one have to use EQ to alter the vocal frequency spectrum. The fundamental region is important in that it allows us to tell who is speaking, and its clear transmission is therefore essential as far as voice quality is concerned
b) Vowels: Vowels give the power of the voice and occurring over the range of 350Hz to 2000Hz
c) Consonants: Consonants occurring over the range of 1500Hz to 4000Hz contain little energy but are essential to intelligibility

For example, the frequency range from 63 to 500Hz carries 60% of the power of the voice and yet contributes only 5% to the intelligibility. The 500Hz to 1KHz region produces 35% of the intelligibility, while the range from 1 to 8KHz produces just 5% of the power but 60% of the intelligibility.

“ By rolling off the low frequencies and accentuating the range from 1 to 5KHz, the intelligibility and clarity can be improved ”

The effect of EQ on intelligibility:

a) Boosting the low frequencies from 100 to 250Hz makes a vocal boomy or chesty.
b) A cut in the 150 to 500Hz area will make it boxy, hollow, or tube like
c) Dips around 500 to 1Khz produce hardness
d) while peaks about 1 and 3Khz produce a hard metallic nasal quality
e) Dips around 2 to 5KHz reduce intelligibility and make vocals woolly and lifeless
f) Peaks in the 4 to 10KHz produce sibilance and a gritty quality

Effects of Equalization on Vocals:

For the best control over any audio signal, fully parametric EQ's are the best way to go.





The important of EQ to vocal intelligibility:

a) Too much boost between 2 and 4KHz
b) Can mask certain vocal sounds such as 'm', 'b', 'v'.
c) Too much boost between 1KHz and 4KHz can produce 'listening fatigue'.
d) Vocals can be highlighted at the 3KHz area.

Accentuation of vocals:
The range from 1.25 to 8K governs the clarity of vocals.
Too much in the area of 5 to 16K can cause sibilance.

Reference : Internet Sound Institute (www.soundinstitute.com)

B.E.A.M Walking Robot

Walker Ver5.3

This is extracted from a guy who is good in designing a BEAM robot; four legs walking robot ( using five motors). He claimed that this particular robot is his third generation five motor walker and he had fine tune the system.

He said that this walker is absolutely incredible to watch and it pushed him through the barrier between building BEAM toys and building a true robotics research platform. Look at that wires use for the experiment. As I have said earlier, you have to be really interested and have the patience to go through this time consuming experiment and don't give up. The good thing about this experiment is that you learnt a lot by doing rather than just reading i.e. theory.

Very interesting isn't it. To know more of his Beam creation Robot walker, kindly visit his site at :


Beam Walker

The "Whack-it" Technique to Desolder

Tools for desoldering?

I've read an articles from the net about the subject desoldering. This guy was having difficulty in desoldering despite using all the necessary gadgets such as solder pump and copper wick. Well, there are many factors that affect desoldering, one of them is the solder iron it self. If the tips of the soldering iron is not clean prior to using it, you will for sure face difficulty. The soldering bit will not properly melt. One way to clean the bit is by rubbing it with a damp sponge. You will notice the clean shining surface once the bit is clean. The solder will melt fast and make it easier for the solder pump to suck it.

Another way is to use the technique "Whack-it". However please be extra caution.

First of all, you must apply safety precaution such as:

1. Wear safety glasses.
2. Your work surface must be prepare to accept slight abuse.
3. You should not do anything that might injure other people nearby when using this technique.

now lets start, heat up the solder iron and heat the solder connection, then rapidly smack it down against the work surface ( did you read the second requirement above? just to make sure you understand what I meant).

The molten solder will fly out, hit the surface and harden into a metallic splatter mark. Never do it directly in front of your face - hold it off at an angle so that there is no chance that back splash might come back at you. Although this is leathal, it sure the quickiest way to get rid of that stubbond solder out of the PCB. Anyway use it as your last resort if you get really annoyed or you feel impatient. But again please be careful. You are free to use this technique at your own risk. No one to be blame if you injured yourself except you yourself.

ROBOT USING BEAM TECHNOLOGY:

For those of you (robot builder) out there who need more information or perhaps a complete documentation to help you build a Robot using beam technology, kindly visit the following link below:

SOLARBOTICS

Apart from those useful document, the site also provide you with plenty of parts, spare part for building simple to advance robot. For the beginners, it may take you a while and plenty of experiment to fully able to understand the mechanism or how the all system works together as a complete functioning robotic that can move, jump, sprint, crawl and so on and so forth. Building robot does not require you to have a formal education in electronic engineering. What important is that you must like robot and always want to know more about robot, be it simple or advance robot. Be willing to spend your time to read, study, experiment, and most importantly build them yourself. There are plenty of books, info, articles in robotic, in the net you can find thousand of documentation, in fact some site give a free tutorial with pictures, to show you step by step on how to build yourself your very own robot.

Until you have successfully build your own robot, you will not know the feeling of excitement and the feeling of deep self satisfaction, as if you have given a life to these miniture mechanical creatures. Robot have always and will always facinate me ever since I was a boy.

Scavenge Robot Parts

You can scavenge robot parts via faulty,damage,broken,dead electronic devices that people may consider trash. The parts that you are mosly interested are listed as follows:

• Motors - DC motors, Stepper Motors but very rare AC Motors (not very common in building a small robots), vibrating Motors( Mobile phone or pager)



• Switches - micro switches, ON/OFF switches,Flip switches..



• Capacitors - Electrolytic, monolithic, tantalum capacitors.



• diodes



• resistors



• integrated circuits - 555 timers,PN2222,2N3904,PN2907,...etc



• Pinch rollers, pulleys, gears,belts,..



• Metal rods ( toner catridges), Plastic Sheets.



• Gear headmotors - mechnaisms that move slowly.

Always be polite when it comes to asking for somebody else's electronic trash. Be very sure to ask whether it's garbage.
Gear motors are GOLD or very useful in robot building. The best gear motors are made by Micro-Mo,Maxon,Mabuchi,Nihon and Namiki (to name a few).

TIPS:

• Never expose an IC to more than 6 Volts, unless you're darn sure it can handle it. This means no hooking your circuit up to 9 Volt battery without a way of reducing the voltage!
• Never sit on an IC especially if it's pins up otherwise you will have a nasty jump which leave a very embarrasing set of bite marks. Those pins are quite sharp. Every now and then the pins manage to poke into my finger if Im not careful.