understanding the signal core

Do we as listeners and designers really understand the signal core?



It never hurts to go back and look at the basics.

Capturing Sound

Sound is vibration and travels in sine waves similar to other types of energy. When these waves reach our eardrums, they make the thin membrane vibrate, changing pressures inside the ear. Recording audio works much the same way.

Microphones are the most common tool for capturing sound. They contain small membranes, much like the human ear drum, which vibrate with the pressures of sound. The fluctuations of the membrane, when mapped out, create an image of the changing pattern of the sound wave.


Copying Sound as Analog Signal

Sound cannot be directly transferred through audio cable, so it must be copied. When a microphone's membrane, or diaphragm, vibrates, it creates electrical signals which are sent along wires through a cable. Because electrical current travels in waves very similar to those of sound, these signals mimic the fluctuations of the original sound wave. This copied waveform is called analogue or analog signal.


Recording Analog Signal

Recording analog signal is as simple--and diverse--as copying down the wave patterns from the sound. Early devices used malleable metals like tin, later replaced by vinyl records. More modern alternatives are magnetic tape or digital code. The latter has all but replaced earlier means of recording, as it is capable of mimicking a signal with incredible accuracy. Still, many recording artists and engineers claim that magnetic tape sounds better when played.


Changing Analog Signal Back to Sound

Speakers are the opposite of microphones, but they have many of the same components. Speakers have diaphragms as well, which take on the opposite role of a microphone's. When a speaker receives an analogue signal, it interprets the wave fluctuations. The diaphragm then mimics these fluctuations, causing the air around it to vibrate. If the signal was strong and unchanged, the sound from the speakers should closely mimic what was recorded.

Hope that was clear enough, but what is the other part to the audio signal? The electronic part?

Electricity is an energy form caused from the movement of little particles called electrons. The flow of these electrons from one atom to the next is called "electronic current". Just like any form of energy once pushed the electrons (electricity) starts jumping from one atom to the next and flows as a pathfinder traveling through the channels of the least resistant always looking to form the ultimate goal of energies shape a sphere or wave. Electricity can travel through a surprisingly small conduit and still deliver the charge needed to supply current to the audio parts that run your stereo. In Our tests 32 guage wire will pass enough electricity to get the job done and 22 guage cable is a nice size conduit to both pass the electricity and be somewhat stable as the current flows.

Why is this important?

The audio signal that travels down a wire or though parts has a correct bandwidth of size vs the amount it vibrates in order to carry the audio signal with the smallest amount of distortion possible along with the ability to be a good electronic current provider. It may sound weird to hear bandwidth used this way but because we are talking frequencies I felt we could bend this word into a good visual representative. Through testing the signals full range capabilities we have found that if the audio signal is traveling through a conduit that is too big the signal itself takes on a form of additive distortion. Something that is not there in the original audio source. The fater the cable the more we picked up this extra signal. What we found is the closer we got the signal to the 32 guage (up to 1 foot of travel) the more open the sound got and the tighter as well. The problem with the smaller cable is it didn't stay stable long and with regular playing the vibration of the audio signal itself at regular volumes made the smaller cable distort constantly in a state of settling. 22 guage is a great size able to deliver the signal without too much extra signal yet holding shape so that the signal did not over vibrate. The guage also gave us a distance range of length vs charge and signal that worked well for most audio needs.

Not only does the audio wire make a huge difference but so do the audio parts.

Again in our testing we found that many audio parts (resistor caps and inductors) are much to big and bulky and start to cause electricity flow restrictions that dampen the signal and cause distortion.

Can you hear this? Absolutely and this is one of the big mistakes in many high end audio designs. When we started testing parts at first we thought the bigger more mass parts sounded cleaner and tighter but after a couple of testings back and forth we could clearly hear the more bulky parts made the music smaller and there was a loss of information. The air for example around a recorded instrument would disappear as if the instrument was in a vacuum. We would go from the studio to the control room and the sound in the recording room would be missing completely in playback room like someone enclosed the instrument in a blanket. We could also hear the instrument going out of pitch in the playback. Yes, out of pitch! We would tune the instrument in the studio and play it back using the less mass parts and the instruments would be in tune, however when played back using the bigger audiophile parts the instruments clearly went out of tune and got pitchy not able to hold their note structures as long. The instruments also with the bigger parts seemed to gather around the speakers and cause a horseshoe sound stage as opposed to a more open relaxed sound with the smaller lightly coated parts.

How easy is it to screw up the signal core?

I think that we sometimes make our own messes and in the case of audio equipment we have certainly not been the safest of listeners. It sounds really impressive to listen to a designer come up with a curcuit and explain it, but I read and listen to many of these guys and can't help but wonder about their own listening environement or testing room. Do they really understand all three (acoustical mechanical and electrical) parts of the audio trilogy? Or are they basing their design on theory and not listening to the subtleties and nuances of music content and how important harmonics and note construction are?

One area that has always caused me fear and trembling is the missuse of inductors and other parts.

An inductor, also called a coil or reactor, is a passive two-terminal electrical component which resists changes in electric current passing through it. It consists of a conductor such as a wire, usually wound into a coil. When a current flows through it, energy is stored temporarily in a magnetic field in the coil. When the current flowing through an inductor changes, the time-varying magnetic field induces a voltage in the conductor, according to Faraday’s law of electromagnetic induction, which opposes the change in current that created it.

An inductor is characterized by its inductance, the ratio of the voltage to the rate of change of current, which has units of henries (H). Many inductors have a magnetic core made of iron or ferrite inside the coil, which serves to increase the magnetic field and thus the inductance. Along with capacitors and resistors, inductors are one of the three passive linear circuit elements that make up electric circuits. Inductors are widely used in alternating current (AC) electronic equipment, particularly in radio equipment. They are used to block the flow of AC current while allowing DC to pass; inductors designed for this purpose are called chokes. They are also used in electronic filters to separate signals of different frequencies, and in combination with capacitors to make tuned circuits.

capacitor

A capacitor is a passive two-terminal electrical component used to store energy electrostatically in an electric field. The forms of practical capacitors vary widely, but all contain at least two electrical conductors separated by a dielectric (insulator); for example, one common construction consists of metal foils separated by a thin layer of insulating film.

When there is a potential difference (voltage) across the conductors, a static electric field develops across the dielectric, causing positive charge to collect on one plate and negative charge on the other plate. Energy is stored in the electrostatic field. An ideal capacitor is characterized by a single constant value, capacitance. This is the ratio of the electric charge on each conductor to the potential difference between them. The SI unit of capacitance is the farad, which is equal to one coulomb per volt.

The capacitance is greatest when there is a narrow separation between large areas of conductor, hence capacitor conductors are often called plates, referring to an early means of construction. In practice, the dielectric between the plates passes a small amount of leakage current and also has an electric field strength limit, the breakdown voltage. The conductors and leads introduce an undesired inductance and resistance.

resistor

A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element.

The current through a resistor is in direct proportion to the voltage across the resistor's terminals. This relationship is represented by Ohm's law:

where I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms.

The ratio of the voltage applied across a resistor's terminals to the intensity of current in the circuit is called its resistance, and this can be assumed to be a constant (independent of the voltage) for ordinary resistors working within their ratings.

Resistors are common elements of electrical networks and electronic circuits and are ubiquitous in electronic equipment. Practical resistors can be made of various compounds and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickel-chrome). Resistors are also implemented within integrated circuits, particularly analog devices, and can also be integrated into hybrid and printed circuits.

The electrical functionality of a resistor is specified by its resistance: common commercial resistors are manufactured over a range of more than nine orders of magnitude. When specifying that resistance in an electronic design, the required precision of the resistance may require attention to the manufacturing tolerance of the chosen resistor, according to its specific application. The temperature coefficient of the resistance may also be of concern in some precision applications. Practical resistors are also specified as having a maximum power rating which must exceed the anticipated power dissipation of that resistor in a particular circuit: this is mainly of concern in power electronics applications. Resistors with higher power ratings are physically larger and may require heat sinks. In a high-voltage circuit, attention must sometimes be paid to the rated maximum working voltage of the resistor.

Practical resistors have a series inductance and a small parallel capacitance; these specifications can be important in high-frequency applications. In a low-noise amplifier or pre-amp, the noise characteristics of a resistor may be an issue. The unwanted inductance, excess noise, and temperature coefficient are mainly dependent on the technology used in manufacturing the resistor. They are not normally specified individually for a particular family of resistors manufactured using a particular technology.

As I was finding the way I wanted to define these I could feel the beads of sweat building up on my forhead  . You mean our audio signal has to go through this and more?

In the Stereo Review days we went through "all parts of the same value sound the same" then "all parts are not all equal" a few years later, to now "only audiophile parts sound good".

I don't know about you guys but I've been to enough high end audio design houses that when these bold statements are made I want to run for the hills. I open up chassis and look inside in horror. I see closed up boxes of magnetic nightmares. I can not count how many times I have made no changes to the circuit at all but only removed the chassis and separated the parts to find a completely different sounding component.

You would think this would be obvious. You would also think that we would study the sound of parts and the reactions with all the other parts would be standard.

It will not take you long to look at this hobby and see that it has over built itself. It has turn simple into complicated and in doing so has gotten further away from the audio truths that were found a few years ago. Simply built products, probably without knowing, are being produced that out perform the huge monsters and when I look inside of these it makes me think that we have been given a fresh start to do this all over again and this time do it right.

On my tuning bench I can take these simple products apart like I did the high end audio ones and go places I have never heard the industry go before. This is great news for the listener and great news for the audio industry in general. Parts that are able to keep the signal core more consistant through the entire audio chain will deliver far more music than systems that have too much resistance built into them.



Think that the bigger parts deliver more music? This is a misconception. The part that operates at it's optimum will deliver more music. Audio signal works similar to but not exactly the same as electronic current. The way the electronic current heats up a conduit and the way it travels down the pathway does not mean the audio carrying part of this is going to do the same thing.

As a system settles the parts carrying the signal become more evenly distributed. When you first turn on a system most of the audio signal travels along the surface of the cable or conductive part. As the system is on a while the signal starts to fill in throughout the whole conduit. The longer the conduit settles the more filled in the signal becomes and the more music gets delivered. With conduits that have bigger surfaces this burn in takes much longer and by the time you are done listening the audio signal may not even be close to full charge.

In audio terms bigger is not better. The same thing happens with weight. A heavier driver and cone will take far longer to make consistant sound waves than a driver and drive system that is low mass.

Greetings Zonees

Agree with Michael absolutely!

Sonic has tried cables and found in a well balanced system in a properly treated room, thin cables of 22 awg or thinner give music and speech the breath of life. When I refer to speech, I have listened to records of Shakespeare and various recitation. Thinner cables give naturalness of voice and the best articulation.

Poetry is another telling test for sound systems. It has rhythm and inflexion and when a sound system corrupts all that, then the meaning of the poem, the sonnet, the passage is reduced.

In systems that are unbalanced, like squeaky mini monitors, then thick cables may have superficial benefit.

One listener has these mini things and told me that he tried solid core 24 AWG and it was too weak, so went to multi strand and "shotgunned" them, that is pairing and tripling them up. Yes the bass end was more prominent but everything else sounded ponderous. OK, the listener was happy but to me everything sounded thick and slow....like trying to swim through molasses. How long this listener will tolerate such a sound remains to be seen.

Perhaps this listener fell into the same trap that Sonic has occasionally which I am discussing in my thread these last few days -- Objective Fixation. This is excessive focus on one goal and ignoring the other problems that crop up along the way when trying to achieve that goal.

So in the case of the mini-monitor...the listener says I want more bass...so he tries according to conventional wisdom these thick doubled up cables...he may get more low end warmth but fails to notice the treble is rolled off and smeared, the soundstage is gone odd, the image size has gone off....yet because the bass end is the goal to be achieved all the other flaws are ignored until down the road someone comments or a comparison with another system is made.

In Sonic's varied systems in my dwelling, thin solid core cables from Michael -- Picasso Interconnects and the T1, T2 and T3 speaker/general purpose cables -- have always proven to deliver the musick. On occasion I may deviate and try something else but in the end the 22 AWG solid core from Mr Green sound more like the real thing and I go back to it. From experience I avoid any cable that is thick, has network boxes attached or made from silver or insulated with lossy elastomers.

Sonic