Audiophile Help Required

[Funky Diver]

Right, I' gonna bow to my lesser knowledge here and admit defeat.

Quite simply, I'm confused to beggary, so if someone could help me out, I'd appreciate it. In terms of the practical wiring stuff, I'm perfectly happy to do all of it, and have a good working ability in wiring stuff in, soldered joints and lead ends, etc, I'm after help choosing the "right" kit. I don't want to go overboard in terms of cost, I'm not building an ear exploding machine... this is for good ole music listening.

In terms of my likes... I like my music "rounded". I don't need really heavy bass, but appreciate that in terms of hitting a bass box, to let the other speakers do their thing better. I get that.

So, all that clap trap sorted... here's the head unit I have in mind - http://www.pioneer.eu/uk/products/25/12 ... specs.html

I chose this for a number of reasons, mainly that it has;

- Handsfree phone shizzle built in
- Direct control of my iPhone
- Direct control of my Pioneer 12 disc boot box
- Direct control over any USB music I might need.
- Decent enough sound control (for my liberal tastes at least!)
- Not overly "faffy"
- AV in for a DVD player etc in future. I may still be whacking a screen in the car, just because. If my kids come to a show or whatever with me, I'd like the option of doing something "with them" when they're bored.
- Fits in with my car redesign
- I like the badge - I've always liked Pioneer kit, and this particular one is not overly bling - it does what it does and does it well - according to the extensive reviews I've read.

So... I now need to choose speakers, and this is where I get completely lost. I can place any reasonablly suggested speakers within the car - tweeters, etc. I'm looking at making a stealth shelf anyways, so real estate up there is good. I don't really need to consider boot space beyond a couple of over night bags. I have an automatic multi-battery isolator with a view to being able to mount a reserve battery in the boot anyways - so I doubt a power cap is going to be a major requirement.

Ideally, I'd like to keep to Pioneer. Stick with what I know and trust is my motto! (as an aside, my AV Amp at home is Sony, but my speakers are Pioneer - and they're AWESOME!)

So come on audio peeps... someone care to give me a heads up as to what to look for so that speakers amps, crossovers, woofer, etc. will compliment each other and the system. (I know the words... but am clueless as to what they ACTUALLY do. Shopping, Handbag, Hormones. See I know the words... beyond bewilderment, not a clue )

[fonzooorooo]

I'll get the ball rolling...

The "what stuff actually does" bit:
Audible audio frequency range is (nominally) 20Hz to 20KHz
From the bottom:
Subwoofer: Covers 20Hz (realistically nearer 30 Hz) up to approx 90Hz
Woofer: (A "Bass Mid Driver) Takes the range 90Hz up to somewhere in the 3 to 5 KHz range
Tweeter: Covers the rest - from 3 (or 5) KHz up to 20 KHZ (realistically cymbals, "S" sound on voices etc)
Crossover: Can be active (after headunit, before amps) or passive (at speaker level) seperates the relevent frequencies off for each driver.


Now for the interesting bit:

It is better to have an amplifier with more power than you need. Always. Fact. ... An amp running "flat out" will "clip" (effectively sends pure DC volts out) which kills speakers. Once they're dead, they're dead. (the voice coil inside burns out)

Crossovers: It is nice to be able to adjust the volume of the tweeters (not just by turning the treble up/down on the headunit!) Active crossovers let you do this (but you need more amp channels, as you need to amp the woofers and tweeters independantly) but some passive crossovers have attenuators which also let you turn them down... so for ease, hunt some of those down.

Speakers: Spend money in the front of the car. Ignore the rear. Technically, you shouldn't need the rears (unless you're running actual surround sound on DVDs)... as they "drag the soundstage back" ... (though in practice, a bit of fill through the rears does wonders masking road noise!)

I am not the one to advise you on equipment though...

[Funky Diver]

That helps immensely, so basically start at the head unit, take the frequency range from there and fill with speakers to match covering the frequency spectrum range.

Then add amps to boost the noise letting the head do it's thing without working it's nuts off just making the noise?

From what you've identified, I'm guessing tweeters and mid-range up front, components on the shelf and sub added wherever is convenient due to it's non-directionality?

Two amps, or one amp with a selfpowered sub, one 4 way amp to deal with main speakers the other bridged to deal with bass.

In terms of amp-speaker ratio, if the combined power of the speakers is, for arguments sake 400 watts, then grab a 500 watt amp. Would that kind of ratio suffice?

[bengould]

You've basically got the general idea yeah.

Ideally using that head unit you will want to wire it something like this....



Completely ignore the 4x50w "Standard" speaker outputs and run two amplifiers a 4 channel for your front components and rear speakers and a Mono amp for your sub. And keep the crossovers as close to the speakers as possible.
If your happy with pioneer buy pioneer. They may not be the BEST out there, but they are far from the worst too.

When choosing amps there is no real ratio to go for as such, just as long as its more powerful than the speakers its driving.
Then turn it all down to suit.

[Funky Diver]

hahaha, I was on sketching that exact same picture!!!

That's awesome guys, I've learnt more in 10 minutes on this thread than the hours I've faffed about on car audio sites. WHY oh WHY do they mess about by making it more complicated than it is???

Right, gonna start some window shopping, but one last question....

Speaker balance. I'm guessing it'd be a good idea to balance the combined the wattages front to rear to make sure that there's some balance in the amp? Or does it not matter?

[Funky Diver]

Right, now down to specifics :D

Maximum power output ....... 50 W × 4
50 W × 2/4 Ohm + 70 W × 1/2 Ohm (for subwoofer)
Continuous power output ... 22 W × 4 (50 Hz to 15 000 Hz, 5% THD, 4 Ohm load, both channels driven)
Load impedance ...................... 4 Ohm to 8 Ohm × 4
4 Ohm to 8 Ohm × 2 + 2 Ohm × 1
Preout max output level ....... 4 V
Equalizer (7-Band Graphic Equalizer):
Frequency .......................... 50/125/315/800/2k/5k/12.5k
Hz
Gain ......................................±12 dB
HPF:
Frequency .......................... 50/63/80/100/125 Hz
Slope .................................... –12 dB/oct
Subwoofer (mono):
Frequency .......................... 50/63/80/100/125 Hz
Slope .................................... –18 dB/oct
Gain ......................................+6 dB to –24 dB
Phase ..................................Normal/Reverse
Bass boost:
Gain ......................................+12 dB to 0 dB

I'm guessing the fact that I'm not driving the speaker directly I can miss most of the Ohm'age stuff out, so long as the Pre-out connectors fit into an amp 4V and under?

Is there anything special that needs to be noted regarding the Sub specifications, again, due to me looping that out of the pre-out?

[ianaudia4]

Lot of info Rich to enable you to listen to Radio 2 and your Tom Jones CD's

[Funky Diver]

haha... I HATE Tom Jones with a passion.

Partial to a bit of dance though... but not thub tumping bass... makes the bowels work on long journeys, LOL

[ianaudia4]

Ha, ha.

[bengould]

Speaker balance. I'm guessing it'd be a good idea to balance the combined the wattages front to rear to make sure that there's some balance in the amp? Or does it not matter?

Ideally yes, but in reality no, because all you want from the rears is "fill" to help cancel out the road noise.

I'm guessing the fact that I'm not driving the speaker directly I can miss most of the Ohm'age stuff out, so long as the Pre-out connectors fit into an amp 4V and under?

Yes pretty much ignore this for now, any car audio stuff will have the correct ohm rating. And any amp will cope with a 4V pre-out.

Is there anything special that needs to be noted regarding the Sub specifications, again, due to me looping that out of the pre-out?

More to do with the type of music you listen to. Generally a smaller (10" and below) sub will cope with punchier bass notes better, where a larger (12" and up) one will go lower and hold long bass notes better.

And finally...

Maximum power output ....... 50 W × 4
50 W × 2/4 Ohm + 70 W × 1/2 Ohm (for subwoofer)
Continuous power output ... 22 W × 4 (50 Hz to 15 000 Hz, 5% THD, 4 Ohm load, both channels driven)
Load impedance ...................... 4 Ohm to 8 Ohm × 4
4 Ohm to 8 Ohm × 2 + 2 Ohm × 1
Preout max output level ....... 4 V
Equalizer (7-Band Graphic Equalizer):
Frequency .......................... 50/125/315/800/2k/5k/12.5k
Hz
Gain ......................................±12 dB
HPF:
Frequency .......................... 50/63/80/100/125 Hz
Slope .................................... –12 dB/oct
Subwoofer (mono):
Frequency .......................... 50/63/80/100/125 Hz
Slope .................................... –18 dB/oct
Gain ......................................+6 dB to –24 dB
Phase ..................................Normal/Reverse
Bass boost:
Gain ......................................+12 dB to 0 dB

All of that is for those that want to make it more complicated than it really is. An average set up with the correct speakers in the correct place will produce more than adequate sound for 99.9% of the worlds ears.

[Funky Diver]

Thought as much, cheers!! :D

Now to try and do some internet window shopping hehe

[fonzooorooo]

Ignoring the headunit's inbuilt amp is the way forwards.

As for amp and speaker power, just as in Hi Fi, and PA, the ideal is to never turn the "volume control" past 2 o'clock. That avoids clipping issues, but it's very hard to determine that on multi-amp setups. My point is, that specifying 500W speakers and 600W amps is irrelevant, as you'd never have the amp turned up

With decent speakers, and carefully set up amps, you barely need EQ on the headunit. The most useful control is a subwoofer output level control, as road noise soon masks the sound of the sub.

As for postitioning/cabling, I'm running small 2channel amp in the front (mounted on the shelf under the glovebox, since you asked!) for the front speakers, then a 4 channel amp in the rear of the car for rear speakers and 2 chanels bridged for the sub. - just saves running an extra set of long cables front to back.

From what I've read, avoid active subs.

As you'll have gathered form my other posts (rantings) on the topic, the sound of the sub comes as much from the box it's in as it does from the sub itself.
A 10" sub (a decent one, anyway!) will still play low notes. Just for reference, the lowest string on a normal 4 string bass guitar has a FUNDAMENTAL pitch of 41.2Hz. (the lowest "part" of the pitch range produced by the string - there are harmonics, but all sound above the fundamental pitch.)

I've mentioned this, because the trade off in cabinet design is efficiency:low frequency response. A small box with a 10" will sound louder than a large box with the same driver, but the large box will (by containing more air for the driver to compress, so the driver can move further) sound a lower pitch. That said, I tried plotting 2 cheap 10"s ("Coustic" subs off ebay), and the box required to get flat response down to 30 Hz would fill the boot to about 4" below the parcel shelf!

So... if you've got the power to drive it (and a driver that'll take that power) you can make 10" and 12" speakers sound very similar (particularly if the 12" is judged in an "off the shelf" box!) The same then goes on to apply to 12" vs 15" and again with 15" vs 18"

This is why I'm such a fan of winISD - you can overlay the SPL or fewquency response plots of a range of drivers in a range of cabinets, and decide EXACTLY what you have space for, and have a good idea of how it'll sound before you saw any wood up!
My preference is to get the flattest response I can (within reason!) and cope with the increased power drain.

In case you're interested, I may have a rather good Rockford Fosgate 12" up for sale soon... Works well in a box that's sensibly sized (1.6 cu.ft from memory)...