Hi Fi confusion.

People get messed up in this term "Hi Fi". Hifi actually means high fidelity, that's it, regeneration of sound as close to original as possible.

So, the equipments will be:
1. Source- CD players, LP players (long play), tuners, hard disk streaming, cassettes etc.

2. Pre Amp-this amp controls the power amp with varying voltage different. For your info, power amplifier has only one fixed gain (signal amplification factor).

3. Power Amp- This amp drives the speakers. It amplifies signals, making it very large and could move the speaker diaphragm.

Integrated amp is where the pre and power amps both joined together in a "thing", sharing the main power source. It's more convenient to be used, but it can't give as much power output as the mono blocks (aka power amps). Separated power sources of the pre-power combination gives a better control of the power source, hence eliminated the possibility of left & right channel power being unequally distributed (especially when driving fast paced loud).

Other stuff:
a. Amp can be further divided into tube amp and solid state.

b. Amp can also be divided into class A, A/B & D.

c. CD player can be further divided into 2 compartments: Transport>DAC (digital analogue converter).

d. etc etc....

e. Hardest thing in hi-fi.. Room tune.

That's it!

Oh my God!

I started to read some cognitive speech stuff recently, there was this chapter talking about human's ear mechanics. It was OMG!

I thought it was just a sound wave (change in air pressure) on the outer ear, then the wave is being transferred to the ear drum, then to the oracle bones thingy and at last it reaches the cochlea. Through the nerves, the signal was brought to the brain. Then finished!

But now that i read something on that, only i know that the oracle bones serves as a signal normalizer, then the cochlea will somehow "filter" out the super sonic frequencies. Dog has different cochlea size, hence they hear a wider bandwidth. Then at the end of the cochlea, there is a hair thingy. There are up to 2000 hairs (if i'm not mistaken), that will convert the mechanical signal to electrical signal so that it can be send up to the brain.

And, one of the most interesting thing is, the speed of the electrical charge moving in the nerves is a lot slower than the speed of electron in a normal copper wire. But, how? How we manage to transmit a complex and up to micro-second signal? Scientist say that the 2000 hairs, each will take a different signal and reach the brain. When the brain reads it, it'll regroup them and that you can understand... OMG! Now i know!

How they did that? It's like 2000 cables running into a mixer and expect the mixer to automatically (programmed to be) put up nicely + "loseless" signal.

[Nerve system's limitation eg. For a normal person with height around 1.6m, there is a fraction of a second needed for the signal sent by the brain to reach his feet, so that the feet can react. Means, a lag. Hence, usually an organ player have to memorize the feet movement, because they have to move their feet to the right pedal and step on it before they can "hear" the sound. When they know they "hear" the sound and only after that they react, everything'll be too late! Interesting!]

"God CREATES that."

Ref: Music, Cognition and Computerized sound: An Intro to psychoacoustic-MIT press

Mixing. EQ

Equalizer (EQ)? You may find it on some mini hi-fi. The most basic one can be "tone" or "bass, treble, mid" adjustments. Hence, an equalizer serves as a device that changes the characteristic of a sound.

There are quite a number of them, from the smallest basic treble-bass that kind, to the 32 bands frequencies wide range graphic EQ, and to the most sophisticated parametric EQ.

Why change the sound characteristic? Isn't that original sound is the most important? The most expensive amplifier gets the most original sound, right?

Actually, in my personal view, original sound is important, but when playing in a band/orchestration, some frequencies can be eliminated to ensures the clarity of every instrument. For example, when u boost 100Hz for the kick drum, you may as well want to decrease the 100Hz of the bass guitar while boosting it at maybe 250Hz (its very own place in the wide frequency spectrum) . This is to ensure that they don't overshadow each other. Ensures clarity!

People usually likes to make a "smile" face on the graphic EQ on their home system, this is due to a psychoacoustic effect on human's brain. Our ear tends to accept and translate sound level in a non-linear scale. Meaning, while you hear the midrange frequency doubled its "loudness", it doesn't mean that your brain takes bass (same power of boost) as doubled loudness. Usually we are weaker at the bass and treble response at low volume, hence we tends to boost them up in everyday consumer hi-fi. But in live music where the SPL raise till a significant loudness, things become different. EQ is then used for the clarity and the feedback control. If used wrongly (if overboost), it may cause distortion. Distortion destroys speakers.

Still, original sound will be the most important thing.

Yet, how come... Perhaps a room having weak acoustic don't meant to be mixed nicely? But, when i play CD on it, it sounds just fine, just a little bit muddy/draggy.. How to mix in a semi mic in room? How to mix if there is some instrument that just doesn't need nor can be mic in? How to compensate? Any idea?

Tritone substitution. It's classic, yet modern!

Lets talk about big band..

When we listen to big band, usually we find that there are a lot of weird chords jumping around, pop out suddenly and vanish during the second stanza (although 1st and 2nd stanza are the same in melody). These may be tension notes, or tritone (for my limited music knowledge)!

Often, jazz players use tension notes, and are made up of 1-3-5 (basic chord notes) -7-9-and the sequence goes on till it repeats again (tension notes). The second rule they use is the root-elimination, 5th-elimination, 3rd-stays, 7th-stays and chosen tension note(s)-stays.

One funny thing occurs: Since there is no root, no 5th, the chord played (together with tension notes) will sound like some other chord, say:

C7: C-E-G-Bb....Eliminating root and 5th: E-Bb
F#7: F#-A#-C#-E......Eliminating root and 5th: A#-E or Bb-E.

Can you see that? So, instead of using C7, some composer tends to use F#7 to substitute C7, and you see these in many r&b songs. With the root and 5th retained, F#7 gives a more 'funky' feel to the overall composing!

If playing a progression like:

|C |Am |F |G7 |C |

it can be alter to
|C |Am |F |C#7 |C |

or
|C--Bb7 |Am--F#7 |F-F#dim7 G#7|G7-C#7 Bdim7 |C---|

or
|C-Bm7b5-E7-Bb7 |Am-A-C#dim7-D#7 |
|Dm9-F#dim7- |C#7-Bdim7-G13-G13b|C--- |

Just try la.. it's fun!

Chords formation theory.

This is just a brief intro to chord formation. There are still a lot more deeper stuff that i haven't come across with as well as its histories.

Usually, we name a chord as major (M) / minor(m) / diminished(dim) / augmented(aug) / dominant / sus4 / add9..

It's actually quite easy, chord forms via a combination of three notes, the 1st, 3rd and 5th. This is the most basic situation, developed since or even before the bach's era. So, what are these 1, 3 and 5? They are actually just 'dol', 'mi' and 'sol' in its respective scale. Say,

• When trying to get C major, use 1, 3 and 5 of C major scale.
• C minor? 1, 3 and 5 of C minor scale.
• same applies to diminished or augmented.

When you meet something like major 7 (CM7) , minor 7 (Cm7) or dominant 7 (C7), what to do?

• Actually is the same just play an extra 7th note of the respective scale.
• for dominant 7, b7 is played instead of 7th.
• sus4? Play 145 instead of 135. This will give a suspended feel since there is no 3rd note, which is particularly important in chord major/minor determination.
• add 9? even easier, just simply add a 9 to 135. it'll become 1235, since 2=9.

If you are playing chords with tension notes, it's quite important to ponder a while which note to throw away, and which note will be kept. Chords like G13 tends to eat up too much space and you have got not enough fingers on the left hand to play all the 1,3,5,7,9,11,13. So, we just take the important stuffs, like root (only if not playing with a bass instrument), 3rd, 7, 13.

3rd determine the characteristic of the chord (M/m/dim/aug..). 7th determine the 7th characteristic (M13, 13, m13 are all different). 13th is the note that causes us wanna use such a complicated chord.

Frankly, if you are playin' jazz, the score will write G7 instead of G13/Gb13 and stuff like that. This is because, G7 is the main feel that the song needed, the '7th' feel, but meanwhile, adding a tension note (becoming G13) is just to add a 'tension' taste to the '7th' feel, and every tension note has its own ways of resolving itself to a 'non-tension' realm. Someone may scold, "what are these 'FEEL' thingy!?" but it's very hard to explain, and still the same qoute, 'feel it, music or any other arts are very subjective!'

Have FUN!!

Tension note.

What are tension notes?

Usually, we see these in jazz music. Normally, we use 1-3-5 in major chords. Occasionally, to add a little touched taste, we use 1-3-5-7, we call it major7.

For jazz players, they tend to add in more. If i draw out a scale in two octaves:

1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16;
where 1=8, 7=15, etc.

So jazz player sees 9, 11,13 as tension notes. Not only these, even the b7, b9, #9, b13, #13 are tension notes as well. Chords involved will be written out such as:

Cmaj9 (1-3-5-7-9 / C-E-G-B-D) or can be written as CM9 (different from c minor 9 "Cm9")

C 9 (1-3-5-7b-9 / C-E-G-Bb-D) - C dominant 9

C mM9 (1-b3-5-7-9 / C-Eb-G-B-D) - C minor major 9

G13 (1-3-5-7b-9-11-13 / G-B-D-F-A-C-E)

Gb13 (1-3-5-7b-9-11-b13 / G-B-D-F-A-C-Eb)

F9 (1-3-5-7b-9 / F-A-C-Eb-G)

So, tension notes' chords tend to have too many notes and are relatively hard to play. Hence, as in making assumptions in physics, we cut off some of the "unwanted" notes:

• The 3rd, 7th and the last tension notes are the most important amongst all others. The 3rd governs the chord's major/minor. The 7th governs the dominant7 / major7. Last tension note is the note you want if you are using such chord.

• The root can be cut off since there'll be a bassist to assist the playing. Playing root is a redundant.

• The 5th sound is not so important, as well as other "lower ranked" tension note. (For 7-9-11-13, 13 is the last tension note and 7-9-11 are the lower ranked.)

Tension notes make jazz chords very difficult to obtained by hearing, especially those root-eliminated chords.. Some chords even have two wanted tension notes, such as:

Cmaj7 (b9 b13).. These species sound pretty wierd!! LOL! But fun to have a try on it..

Augmented and Diminished scale.

Actually i'm not too sure how augmented and diminished chords are used. But, the theory is based on whole tone (WT) and half tone (HT) scale.

For diminished scale, we use whole tone half tone method:

WT-HT-WH-HT-WH-HT-WT-HT

For example, for C diminished we take:

C-D-Eb-F-Gb-Ab-Bbb-B-C (9 notes)

Same method to obtain chord, Cdim7, 1-3-5-7, C-Eb-Gb-Bbb.

OR maybe can use half tone whole tone. Try it out.. Since it already sounds wierd, i can't really differentiate the difference between the usage of WT-HT or HT-WT.

For augmented chords, we use whole tone scale:

WT-WT-WT-WT-WT-WT-WT


Caug scale:


C-D-E-F#-G#-A#-C (7 notes)


C aug means 1-3-5, C-E-G#.

Try it out! Do combing on your left hand (chord) and run up and down with the respective chord scale, should sound quite diana krall, hehe.. (but hers is much more difficult..)

Scales? These are some of what i know!

In scales, we take C major as a main reference, it's easier to imagine. Imagine on a keyboard, 'C' is the 'do', or 1st. It then continues to 'D-E-F-G-A-B'. While looking to the black key, we notice that there are black key gap in between some two adjacent white keys. In this key, it's obvious that 'E-F & B-C' have no gaps in between.

• If there is a gap, we call it wholetone (WT).

• If there is not having any gap, we call in semitone (ST) .

For any major scale, it's ascending this way:

WT-WT-ST-WT-WT-WT-ST


To makes things easy, just imagine the black keys of piano, it's exactly the same.

So, what about minor? It's something like this:


WT-ST-WT-WT-ST-WT-WT


Observe it carefully, it's actually just a shift of the major scale. Hence, we can say that if you play C major scale, but start with A (the 6th note), it's the minor scale of that particular key, in this case, A minor scale:

A-B-C-D-E-F-G

Neither sharp nor flat occurs, it's just another identical C major scale, just that there is a shift.

Same thing applies to some basic jazz mode,

Dorian: starts with 2nd.
Phrygian : starts with 3rd
Lydian : starts with 4th
Mixolydian: starts with 5th
Aeolian: starts with 6th (another name for minor scale)
Locrian : starts with 7th.

Hope that it cures the curiosity on basic scale forming.