7. Upgrades & add-ons
Once you have your basic hi-fi system, you may begin to search for improvements in sound. This may not have to mean taking out a second mortgage to fund your quest for aural satisfaction. There are a number of relatively simple and inexpensive ways to upgrade your sound.
- Upgrade your amplifier
- Bi-wire your speakers
- Bi-amp your speakers
- Add a subwoofer
- Use an outboard DAC
- Use quality cabling
- 2nd zone speakers
Upgrade your amplifier
Amplifiers can be a contentious issue amongst audiophiles, and usually results in spirited debate about tube versus transistor, voltage versus current etc, but we won't go into that. In general terms more clean power equals greater dynamic range.
What is the dynamic range? It is the difference, in decibels, between the quietest and loudest portions of a musical performance. It is also the difference between the noise floor and the maximum signal level of electronic equipment.
Greater dynamic range in the equipment you use to replay your music collection opens up the soundstage (where the instruments appear to be placed on the stereo stage between your speakers) and allows you to hear the musical performance in greater detail with more definition and clarity.
Bi-wire your speakers
Bi-wiring your speaker involves using two runs of speaker cable from the amplifier to each speaker to separate the high and low frequency signals. The benefit of this is greater bass control and crisper, cleaner treble. This is heard as a greater focus of the sound with better presence and detail.
One of the problems with a standard crossover on a speaker is that since one pair of cables carries the signal to and from the amp, bass signals can tend to swamp the more delicate treble stuff. By separating the signal all the way back to amplifier's output stage, using two runs of cable or a purpose-made four conductor bi-wire cable, these effects can be greatly reduced.
If your amp can drive your speakers, it can drive them bi-wired, but the speakers need to be designed to be bi-wired. In a bi-wirable speaker, there are four speaker cable terminals. This is because the two halves of the crossover (the circuit that splits the signal into highs and lows, and sends them to the tweeter and mid/bass driver respectively) are physically split into two sections. One section filters out low frequencies from the feed to the tweeter; the other loses the high frequencies from the terminals connected to the mid/bass woofer unit.
Bi-amp your speakers
This is one step further than bi-wiring. If a speaker can be bi-wired, it can also be bi-amped. This involves using one amplifier channel for each drive unit to give further improvements. A stereo pair of two-way speakers will therefore need four channels of amplification. The easiest way to do this is to use your existing amplifier along with a second power amp. This is like combining the two upgrades already mentioned. You double your power, which is beneficial to the dynamic range and soundstage, and you separate the low and high frequencies resulting in a more articulate and defined sound.
Before attempting to do this, make sure your existing amplifier has a pair of pre-out sockets. Some amplifier models are designed in this way, having pre-outs that work in tandem with their own power sections. If in doubt, ask us first.
Another point is that the second power amp you use should have the same gain (though not necessarily the same power output) as your existing amp. That means that for a given input voltage, both your amp's onboard power section and the external power amp you use will give the same output. If they didn't, you'd have a sound with much louder bass than treble, or vice versa. In general terms, the requirement for this gain-matching means using combinations from the same manufacturer, designed to be used together. Again, check with us if you're not sure.
The integrated amp and the power amp are connected together with a stereo pair of interconnect cables, pre-out on the existing amp to pre-in on the second power amp. You then use one amplifier to drive the left and right treble (or high frequencies), and the other to power the left and right bass. In general terms, you would use your existing amp to drive the treble, and the second power amp to drive the bass, but it's worth experimenting.
Add a subwoofer
There's just no substitute for the kind of impact a subwoofer can add to your music. The depth and dynamic effect can rarely, if ever, be achieved by conventional loudspeakers. Let's be careful here though: a subwoofer should never be overtly present in the music. The purpose of a subwoofer is to compensate for the bass response drop-off from normal speakers so that a full spectrum of frequencies is accurately represented. High fidelity is about achieving an accurate, uncoloured reproduction of the music so obviously a booming, muddy bass will take away from that.
Subwoofers typically play frequencies between 20 and 100Hz. Bass response in bookshelf speakers generally rolls off at about 80Hz, and in floorstanding speakers, anywhere between 80 and 40Hz. A subwoofer's crossover (the frequency at which the stereo speakers roll off and the subwoofer should begin) should be set accordingly. A subwoofer should be felt more than heard, and that doesn't mean rocking the foundations of your house with subsonic rumbling. The sub is an extension of the stereo speakers and fills in the information that they cannot. In fact, the impression should be of a seamless transition across the frequency spectrum.
Use an outboard DAC
One way to get more out of your CD player (other than replacing it) is to use an external digital-to-analogue converter (DAC). Your CD player has one already, but unless you have one of the more high-end models, chances are it could be improved, and as mentioned before, a component that only has one job to do, generally does it better.
An external DAC performs the digital to analogue conversion normally done inside your CD player. That is, once the transport mechanism reads the computer bits off a CD, it must be converted from its digital form to an analogue signal. Whether your DAC is internal or external, you do have one somewhere if you are successfully listening to CDs.
To hook up an external DAC to your CD player you need to have a digital output. On most standard CD players this would be either an optical or a coaxial output.
Why do you need an external DAC?
Well, as technology improves the digital to analogue conversion process, it can be a very cost effective way to perform an upgrade. And as we've said before, separate components (eg. transport and DAC) will yield better performance. A good DAC can make a significant improvement in the listening enjoyment of digital audio.
Use quality cabling
Why spend money on cables—isn't a wire, well… a wire?
No. Unequivocably no.
A lot of people use whatever cables come standard with their equipment and assume that that's fine. What most people are rarely told is that the cable is one of the most important links in the stereo system chain. Or rather, it is as important as every other component in the chain from recorded medium to aural satisfaction. As we all know, a chain is only as strong as its weakest link.
So why are cables so important? The answer is actually very obvious when you think about it—they carry the signal from the various components to your speakers. What is the point in spending thousands of dollars on a high fidelity system, only to have a significant amount of the music's frequencies disappear through added distortion and interference, due to cheap and nasty cabling? Surely that's an exaggeration! No, it is not. Thin, poorly isolated and poorly designed cables introduce extranneous noise and interference which masks and deteriorates the signal. So all that lovely detail, clarity and natural sound we were striving for by opting for quality components goes out the window. Good quality cables reduce distortion to a minimum and keep RFI (radio frquency interference) and EMI (electro magnetic interference) out. When budgeting for a system, keep cabling very much in mind.
2nd zone speakers
Want to hear music in the kitchen while cooking up a feast? A lot of integrated amplifiers and receivers include a second set of speaker outputs and A/B speaker switching which allow you to run a second set of speakers wherever you like. You'll maximise the benefits and realise the full potential of your investment.