Where should you start when tweaking a factory sound system (leaving the existing head unit in place)?
Ashley "First you've got to determine what you want - do you want it to go really loud, do you want heaps of bass or do you want it to be really crisp? Usually, the factory speakers will distort first because you have to crank up the bass on the head unit. What you can do is a simple speaker line-in or convert to RCAs and run an amp with a dedicated sub-woofer. That way to can run the existing speakers without boosted bass."
Luke "Yeah, look, many cars come standard with CD players and lots of people don't want to lose steering wheel controls - if they can improve the quality of the speaker system alone, that's often all they require. One of the first things you need to do if you want to improve sound quality is install good quality speakers. Your can often run these straight off the factory deck because aftermarket speakers are usually very efficient - they use the power coming in from the head unit very well. And with a split system - where you've got a separate tweeter and cross-over - you're running the right frequencies to the right drivers and that helps give a cleaner, crisper sound. In a VR/VS Holden Commodore, for example, there are allocations for splits in the front - drivers in the doors and tweeters in the dash. You pull the standard speakers out, put in some nice splits - like some Pioneers 6-inch drivers in the door and a pair of tweeters up high - and you'll dramatically improve the sound quality."
Are aftermarket speakers generally as sensitive as OE ones and, if not, do you need to buy an amp to drive them?
Luke "Generally, I find aftermarket speakers are more efficient - depending what you're comparing. The better ones have better sensitivity as a rule."
Should you deliberately look for speakers with high sensitivity so you don't need a higher power amplifier to generate the same SPL?
Ashley "No don't get involved in all that sort of stuff, just bring a CD into the retailer and listen to the speakers on the demo board. Get the sales person to set the deck at zero bass and treble. That way you can get a good comparison at least."
Luke "No, It's like buying home audio system - you should listen to as many speakers as you can."
Are demo boards an accurate representation of how speakers will sound once you've installed them to a car?
Luke "At the end of the day, most demo boards are set up to make the speakers sound as good as they can be. Again, at least you can compare apples to apples but certainly demo board is very different to a car."
When assessing where to start making changes to an OE sound system, is it a good idea to listen to the speakers front and rear separately (using the fader)?
Luke "When a new car comes in we can twiddle the controls and identify the areas that need most attention. You can tell if there's no top-end or whatever, absolutely. The factory speakers often aren't great, but in some circumstances you might not need to replace them - you can make the doors a more solid enclosure to begin with. The difference from that alone can be tremendous."
What are some of the best OE sound systems you've listened to?
Ashley "Nissan Maximas have a pretty good factory system."
Luke "The Ralliart Magna with the Eclipse system sounds pretty good - but that's sort of an aftermarket factory system. That particular head unit can be bought straight out of the Eclipse catalogue. To be honest, I listen to a lot of systems but not many factory ones."
How do you decide what size subs - and how many of them - are best for you?
Ashley "Again, you've got to decide what you want. A fifteen has low rumbling frequencies, but isn't all that responsive. Twelves are a happy medium and 10s offer nice, tight bass. To get any real quantity of bass with 10s though, you really need a pair."
Luke "The bigger the speaker the more air it pushes, so the lower and louder it goes. But the bigger the speaker the less responsive it is - it's a heavier cone that isn't great on transients. If you listen to dance music - which is tight and punchy but still with fairly low frequencies - go for maybe a 12-inch, but for R&B, hip-hop and low bass music you might have a 15 or a couple of 12s - maybe even an 18. If you listen to band music with a lot of kick drums and bass guitars I think a 10 or a couple of 10s would do the job well - still nice and punchy. There aren't so many companies making 8-inch woofers these days - there's not much demand for them. The cone area is probably only about the same as a 6 x 9."
What are the pros and cons of ported and bandpass sub enclosures?
Luke "Basically, if you want flat-out SPL a ported enclosure is best - but you lose in one sense because a ported enclosure has to be tuned to a certain frequency. What happens is if a track moves gradually through bass frequencies, it's quiet, quiet, quiet, loud at one frequency and then quiet again. If you're looking to break records a ported enclosure will give a lot of bass - it forces air out of the port as well as the front face of the driver. That's why it's so loud. On the other hand, a sealed enclosure - although not quite as efficient - is typically more balanced and gives smother response. There are no peaks or dips."
What effect can the wrong box specs have on sound quality?
Luke "It can make a huge difference. If a speaker is designed for a certain box it really needs it. You can put a sub in the wrong size box and you might think it sounds great, but chances are it's performing a long way off its optimum."
How do you determine the appropriate box specs?
Luke "Luckily there are computer programs that work that out - but it's a lot of work to collect all the specs and go through it all. More often, though, you buy a speaker in a box that's already suited to the driver. That's much easier"
Are 6 x 9s a popular and wise purchase for someone on a budget?
Luke "Yeah, we still sell heaps of them - especially to the younger market. Six by nines make a lot of sense financially, because you don't have to outlay for a sub in a box and an amp. Of course, 6 x 9s don't give anywhere near as much bass as a big, powerful sub but they're pretty good. They are certainly great bang for the buck - you don't need to run an amp to 6 x 9s but, again, they will sound a lot crisper."
Luke, you mentioned (prior to the interview) that you run just front splits, an amp and sub in your own car - what are the benefits of this arrangement?
Luke "It depends on the car - I've got a hatchback, which is effectively a very small enclosure. I've found just some beautiful front speakers - like about $1000 for some Focals - and some nice subs in the back perform great. It's like going to a concert - all the music is in front of you, there's not much from behind other than a bit of reverb and reflection. In a car that's well set up the band or musicians sound like they're on the bonnet. Sub bass is omnidirectional so you can't tell where it's coming from - that's good because, due to the size of a sub, we have to put them in the back of the car. Rear speakers can be added for a bit of 'fill' - a more surrounding sound. The trade-off is you lose a bit of imagining."
Do you fit many 'free air' subs?
Ashley "No. Legally, it's very hard to do with child anchorage bolts. You can't cut within, I think, 22 centimetres of each anchorage bolt, and a lot of cars have them for the centre and side rear passengers. Basically, you're not supposed to affect the structural strength of the car."
Why are splits better than a conventional door speaker with a high-mount tweeter added?
Luke "It comes back to the cross-over - you want to take the high range frequency out of the mid-range speaker and the medium-range frequency out of the tweeter. If you don't have cross-overs you'll blow the tweeters. The sound from the mid-range driver won't be as good either - in addition to moving slowly to produce bass, it will also be trying to move quickly to produce treble. The low notes then have a kind of warbling effect."
How important is it to use thick cabling and gold plated battery terminals?
Luke "The bigger the cable the more current can flow through, like the bigger a pipe the more water can flow through. It's always better to have the thickest possible cabling. And, yes - with a fairly good overall system - you can definitely pick the difference with a gold set of terminals."
Ashley "A lot of people spend $1000 on an amp and overlook spending $100 of some quality cabling. If you can't get maximum power to the amp you'll lose its performance."
Does adding sound deadening - say, to the inside of the doors - make a cost effective improvement?
Ashley "If you deaden a door there's much less ringing inside the cavity. There's much less reverberation in the door."
Luke
"Look, if you build a set of home speakers using craft wood or Masonite they'll sound terrible, but if you build it out of, say, 12mm MDF you'll have a nice solid enclosure. With a solid enclosure you hear the speaker rather than the reversion inside the enclosure."
Say someone comes into your store wanting to spend $500 upgrading the existing CD system in their sedan - what would you suggest if they're after a nice, clear sound with just enough punch to accommodate turning up the occasional song?
Luke
"I'd say a nice pair of 6-inch splits in the front and, if there's enough money left over, an amp for them or some rear 6 x 9s. That will give you good clarity and should be able to go reasonably loud. It's hard to tell without knowing what sort of car it is."
And what would you suggest if the budget was $1000?
Luke "Then you'd improve on what you've got. I'd step up to the next price category splits, but you could instead buy a sub and an amp."
Where do you see people going wrong designing and fitting their sound systems?
Luke
"Putting a speaker into a door and wiring it up sounds easy but, unless you do it right, it won't sound anywhere near as good as it can. You've got to make sure the speakers have a really good seal. Go to a professional if you're not completely sure what you're doing."
Ashley "I see people putting subwoofers in the wrong enclosure along with a too small amplifier. It just doesn't work anywhere near its potential."
Have you ever weighed a competition sound system?
Luke "My system is over 200 kilograms - that's a custom rear MDF enclosure with neons and stuff. You can actually see the suspension go down when it's loaded in and, when you're driving, it's like having two or three people in the car. We drove the car onto a weighbridge and it went from, I think, 950 to just over 1200 kilograms.
"From a weight perspective, fibreglass is a good thing - you can end up with a good quality enclosure and it doesn't weigh nearly as much. When we do them we treat the inside, keep the side panels small and make the fibreglass fairly thick to keep the enclosure 'dead'. Sometimes we use the acoustic filling - that basically fools the speaker into thinking it's in a larger enclosure. It's good if you want to fit a sub in a Mazda MX-5 (Miata) or something that has a fairly small boot."
Do you have any last words of advice for readers?
Ashley "Before you go out and buy anything, you need to take a look at the car and decide exactly what you want to achieve - and how much to spend. Don't buy equipment because you like the sound of it in a mate's car - each car has its own acoustics and the same gear can sound completely different in another body."
Luke "It works out best when a customer walks in knowing what sort of gear they need for their requirements - that's when people like us can steer them in the direction of specific brands and products. And Ashley's right with how components sound in certain cars - I mean, you put a sub into a hatch and it's very bassy but put the same sub into a sedan and you lose a lot out of it."
Contact:
Tonkin's Car Audio (Adelaide)
+61 8 212 2550
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