February 21, 2010

Majoring on major issues in audio

There is a peculiar obsession in the audio community with the minor issues of a sound system. What is so seductive about spending 95% of your attention on 5% of the results? This would baffle the average person, but for many audiophiles this is their preferred modus operandi. I won't argue with how they choose to spend their money, but if you are the kind of person who wants to get the best sound for your money, I'll share some insights to help you get there.

A few thoughts on why ...

There is the suggestion that if you can hear the difference between cables, your ears are a cut above. Do you dare admit you actually can't hear a difference? There must be something wrong with your ears! Clearly, you have chosen the wrong hobby and you should stick to low fi or try car audio. It runs much deeper than this. Let's suppose that you are a speaker company selling high end speakers. You know that expensive speaker cables don't make a real difference to the sound, but many of your customers are "cable believers." The dilemma is do you demonstrate your speakers with cheap but adequate cables and tell customers the truth - that they are all you need and anything more is eye candy? In so doing the cable believers will take everything you say with a grain of salt and it's likely you will lose sales. But in perpetuating the fantasy, you will gan more sales. I believe this is part of the reason why audiophile mythology is so widespread.

Those in the snobby elitist audiophile camp won't be impressed or convinced with anything I have to say here. But my hope is that those who are open minded will gain some tips on getting more out of their system.

How do I get the most out of my system?

It's simple - major on the major issues! Focus your attention, money and time on the things that make the biggest difference.

So what are the major issues? By far the three biggest are the recording, room and speakers.

The recording
You can't do much about the recording, but you can explore new music. See if there are audio clubs or get togethers in your area, as they are a great way to experience new music that is well recorded. If nothing is happening, jump on the forums and organise one.

The room
Most of us can't build a dedicated room from scratch, but since this aspect is so very important, do as much as you can. If you have a room with major bass issues, you will need to consider an acoustic solution. This could include adding plasterboard/drywall, or adding bass traps to your room. You should also pay attention to aspects like speaker placement and room layout which can make a big difference. Improving your room can be one of the best value upgrades available. There are things you can do for free that can make a real and major difference. A simple change like moving your speakers 1m out from the front and side walls and toeing them in can transform the sound. Suddenly the sound stage emerges where you may have had a wall of sound previously.

The speakers
There is no way around it - speakers are expensive, but the simple and unavoidable truth is that you can't cut corners here. They are necessarily expensive. They are the one and only component that must be expensive. They convert an electrical signal into acoustic sound waves. Outside of the studio, this is the biggest change that happens in the audio chain. It's often said that a sound system is only as good as the weakest link. This is often used as an excuse to spend redundant amounts of money on CD players, cables, preamps, DACs and amplifiers. In reality, these components will almost never be the weakest link. On an entry level budget, you can buy all of these components and they will be as good as they need to be from a sound quality point of view. Very little is gained in spending more. When sound quality is the goal, it's wise to spend what you need to and focus on the speakers. Unless you live in a mansion and can buy the best of everything without sweating over the cost, but few of us have that luxury.

Of course, there are reasons to spend a little more on these components, including realiability, aesthetics, features, warranty and there is nothing wrong with pride of purchase. However, it pays to be realistic about sound quality and to be clear on what you are getting for your money.

While everything else makes a tiny and relatively transparent change to an electrical signal, the speakers make many different drastic changes. The problem starts when the amplified signal reaches the speaker voice coil. Now we are dealing with a motor which is far from linear. As more power is applied, the voice coil heats up and it's resistance changes, causing power compression. At the same time, the cone moves more and with increasing excursion we are dealing with mechancial non linearity. In a perfect world, the cone would move as a perfect piston, but this never happens. So the cone flexes and adds it's own sonic signature. The sound enters the room from multiple sources, each with different characteristics and dispersion. Even the best loudspeakers using the best quality parts and the most careful and expert design will have more compromises and do more to change the sound than the cheapest DVD player you can buy. This might seem like a radical statement to many, but it is one founded upon an understanding of real and indisputable acoustic realities. I haven't mentioned imaging, off axis lobing, baffle diffraction, early reflections, distortion, phase aberrations, frequency response, group delay, impulse response which all have an impact on the sound.

What about upgraditis?

You get the urge to upgrade - it's human nature to want something better. So you bought a NAD preamp 5 years ago and now you want something better, something more exotic. So you spend three times as much on a preamp that is reviewed with comments like "drastically improved the sound stage - I could hear inner detail that I was missing on the NAD." The problem with reviews is that they precondition your expectations at a time when you want to believe what they are saying. A far better choice is to focus on integration. Add some bass traps. Use EQ for the bass. Increase the sub count to 3 and use the multi sub approach to smooth out the room response. These areas will make a real difference.

Conclusion

Spend as much as you can on the speakers. If you have to cut corners, do it elsewhere. Getting the best sound is a problem where the speakers and room are the critical parts. If you buy your amp first and then choose speakers that will suit the amp, you are going about it the wrong way. The most likely result will be that you'll end up choosing efficient speakers that are highly coloured. It's very difficult (and expensive) to gain high efficiency without a great deal of colouration. It's far easier (and much less expensive) to first buy accurate and uncoloured speakers then pair them with a suitable amplifier.

There is one way to get the best sound, but it has many variations. Start with the speakers and the room and consider them together. If the room is a given, then consider it when choosing your speakers as they must work together. Synergy matters here far more so than anywhere else.

Keep in mind when I say "there is one way" I don't mean a narrowly defined path. You might fall in love with electrostatics, you might feel open baffle speakers are the ultimate or you may prefer conventional floorstanders. They are all valid variations, but if you want the most accurate sound, you must consider the speakers and room together and treat them as the most important parts of your system. Choose some well recorded music and if you have a suitable amp for your speakers then you have 95% of the sound covered. Any improvements you make elsewhere in the system will be subtle at best.