Amplifiers: The heart of the car audio system.

In its basic form an amplifier has one job, to take a small signal and make it bigger.

amplifier

This would be so easy if music looked like the above sin wave but of course music is much more complex.

Music is a complex mix of multiple frequencies with varying levels and shapes. Sin waves, square waves, saw tooth waves all layered to create sophisticated patterns of vibrations in the air. Astonishingly our ears can pick up these complex and subtle vibrations and our brains can interpret these signals at a very precise level and let us experience music. Consider listening to a large orchestra. Even when all the instruments are playing it is possible for our ears to detect just one small part rather than a wall of noise. Composers know this and carefully layer instruments to create symphonic masterpieces.

How a speaker can reproduce this is for another discussion but let us consider the amplifier.

The signal coming from the CD player should contain an accurate version of the music at a very low level. I say ‘should’ because a lot of standard fit head units actually do not have a clean signal and this has to be dealt with before it gets to the amplifier but again that is for another discussion. So let’s assume there is an accurate signal leaving the CD player which contains all the subtle nuances of the music.

What happens inside that big box?

As I said earlier, the small signals from the CD player have to be made larger so the speakers can play them but as I also mentioned these signals are extremely complex. Recreating these complex signals requires some very sophisticated circuitry but above all very high quality electronic components.

So what is it you get when buying a better amplifier?

I like to use the analogy of standard, high, and ultra high definition TV. If you have experienced all three types then you know the difference. Standard definition is OK and is, for most purposes good enough. However high definition is sharper and clearer so no fuzziness around the edges making it easier to watch. Ultra high definition takes it to another level and quite honestly it’s pretty much like looking through a window with vibrant and subtle colours, crystal clear images with no flicker or artefacts. You could describe it as just like the real thing and this makes it much less fatiguing to watch as your brain does not have to compensate for the poor image.

Music is exactly the same, the more accurately it is reproduced the less your brain has to compensate for distortion or missing information. This compensation is what causes listening fatigue and can lead to headaches and the desire to turn the system off!

A better amplifier will be able to reproduce every last nuance and detail of the music and you can quickly tell the difference when you hear it. You will notice things in the music that you have never heard before; instruments will be clear and well defined without any muddiness when there is a lot of information playing. Vocals will be lifelike even allowing you to hear the space they were recorded in exactly as the artist intended. This is what a really good amplifier can do for you and why it is always worth spending more to get a better sound.

Someone once told me a good way to describe better and better sound was to think of the artist playing behind layers of curtains, each time you improve the system you remove a curtain until eventually you are standing in front of them.

So what does it take to get right to the front?

The Audison Thesis Venti amplifier. Over £8000 of sonic perfection for two channels. If you want the best then here it is.

If you would like to know more about how we can improve the sound in your car please call us on 01625 432707 or pop into our shop on Sunderland Street in Macclesfield.

 

Digital Signal Processing

Well summer is fast approaching (hopefully) and that means we can finally get the car windows down and open the convertible hoods. While the fresh air and wind in the hair is nice, the open plan car has a dramatic effect on the sound quality from the stereo system. Even stationary, opening a convertible roof completely devastates the way your music sounds leading to a very disappointing performance.

What is going on of course is that certain frequencies are being lost to the outside world while some are retained inside the cabin. The result is usually a great loss of bass and mid-range while the treble stays fairly constant. This results in a very unbalanced sound that simple bass and treble controls cannot fix. However you do not need to suffer as we have the tools to make sure you can enjoy the same performance whatever the configuration of your car.

What we need are two audio systems, one for top up and one for top down. The top down system would need more bass and mid-range speakers with a less efficient tweeter. It would need more power than the top closed system to compensate for the losses and of course we would need to be able to switch between the two systems.

Of course the idea of fitting two different systems for different configurations is not practical but nevertheless it is what we need. So if we can’t do that what can we do to ensure great sound at all times?

The answer lies with signal processing and careful tuning for different car configurations.

Digital signal processing allows us to shape the sound to suit the environment. This is different to simply adjusting the bass and treble controls to suit the music as we are working to produce an accurate sound for the given equipment and vehicle. In addition most processors are equipped with two or more memory pre-sets that can be retrieved at the touch of a button. This effectively means we can have two (or more) different audio systems in one car.

There are many processors available today but which one is best? Well the truth is it’s the one that suits your particular system. It will depend on how many inputs and outputs are required as well as where those inputs are coming from. Are we integrating with a standard head unit or a vehicle’s factory amplifier? Are we to use analogue or digital signals? How many amplifiers are we connecting to? All these questions and more need to be addressed before we choose.

Of course the real power of any processor is its tuning capability and that can only be as good as the tuner!

Even a relatively simple system such as this in my Discovery can look daunting. All crossover points, slopes, levels, time correction and phase are accessible with the software and without a thorough understanding of what is going on it is very easy to end up with a terrible sound or at worst damaged speakers.

In the right hands these tools are extremely powerful. When I tune a system I can bring all my years of musical experience to the project. This means I can give you exactly the sound you want; regardless of how you use it or the configuration of your car.

If you would like a practical demonstration of what a well-tuned processor can do; please call into our shop on Sunderland Street in Macclesfield where I would be delighted to demonstrate our Discovery. It really is a revelation.