Sound Advice Needed

[Pedro]

OK, to start with, I know jack schitt about subs, crossovers, caps and all that twaddle.

I just want a good sound in my car! I have JBL door speakers, JBL tweeters im the dash (all GTO 55, I think).
I'm gonna rip out the Vibes from the Vectra for the parcel shelf.

So far, so good.

As I listen to mostly rock and metal, I've been told that I need a single 10" or 12" sub in a box in the boot so the punch of the double bass drums can be heard nice and clearly. Being a drummer myself, I understand that. I've only heard metal played once that sounded as it should, and the guy had built his system purely to listen to metal. On a few other systems, I've whacked a Metallica or Rammstien CD on, and, frankly, just heard mush. I hasten to add that these other systems usually belted out "boom tsss boom tsss bom tssss"  I dunno what you call it, but it ain't music........... it's crap!

Back to the plot.

What is the best amp/sub/box to get?

I have a JVC headunit with outputs for an amp.

[Murph]

iT'S MOSTLY GOING TO BE A CASE OF WHAT LOOKS BEST IN YOUR BOOT, HOW MUCH YOU WANT TO SPEND AND WHETHER YOU WANT IT BE EASILY REMOVED. Sorry did'nt realise I was shouting LOL 
Anyway, any good quality amp/sub combination should improve the sound for you as you can adjust the amp to suit the music you listen to.
I have two 10" subs in a box with a 200 watt amp (which isnt alot) and it improves rock a treat (I dont do drum 'n' bass either) without the need to blow my ears off to apreciate it.
HTH
Day

[GSI24VBONES]

Good tunes !! i too only have metal CDs in the car
i'm only running a 10" boxed sub and it sound the b@ll@x not bad since it's 10yrs old
it's a 10" Alpine in an alpine box & still sound the same as when i 1st got it
ICE pics in I.C.I section

[blippi]

tbh m8 i gave up on the subs an that awhile back but my advice is 2 buy the best u can afford and 10'' will give better quality were as the 12'' will give louder noise

mine were all phoenix gold and it sounded shit hot back in the old days (god 26 an talking bout the old days lol) I would deffo reccomend there gear

i've heard from others that to make them perform well its best to make the box have the exact cubic space reccomended by the manufacturer so best 2 make your own box

HTH

[colonelk]

10s are defo punchier.

It does come down to......

How much you want to spend?
How much space do you mind sacrificing?
How loud do you want it to be? LOL

[carlton_mad]

2x8"subs some nice mid ranges and tweeters 10&12" are ok for most stuff but for heavy rock 8s react better faster response and all that

[Pedro]

I was thinking a ton (ish) for the bass department?

But do I get a sub with a built in amp, or seperates, passive, active (wtf does that mean??) a bass tube (uggerly looking spuds though), what do you all suggest?

To be honest, the Bose system in the Meega has a diddy ickle sub, but sounds quite good (stereo is the best bit of the whole bloody car! )

I have extended the floor the area where the spare wheel would normally sit, so decent place to put one, I thought.

Loud - hmmm, let me think...............VERY LOUD!!! 

I wanna hear those bass drums on Metallica's "One" without the distortion I usually get............

[Murph]

Active means powered - passive means not (i think)
If you get seperate components you can make a feature of the set up 

[Matt]

Make way - DJ geek coming through..................


OK the difference between 8", 10", 12" and 15" subs:

- The larger you go, the lower the frequencies the subs can handle.
- The smaller you go with your subs, the more punchier they sound. This is because the smaller speakers handle higher frequencies better than larger ones do.
- even 8" subs will handle 25Hz, albeit very quietly, but 15" subs will move more air and you will be able to "feel" the bass.
(ps - 25hz is the lowest frequency in the EQ spectrum - you can't really hear it, more feel it. 18"/21" drivers make a good job of doing that, but you'll not find speakers bigger than 15" in a car. )

The music you listen to Pete will have the bass drums miked up on the recording with lots of bass but a lot of high-mid too. This will give it a "kick" sound, some describe it as a "clicky" bass drum. A nice sound for a rock/metal drum kit.

The best you can afford is the key. If you're going down the sub route for better metal music, I'm sorry but I'd chuck the JVC in the bin (or ebay it) and get a decent Pioneer system. They are the nuts when it comes to car stereos. Alpine and sony are good, but not as good as pioneer. Kenwood are shite. Basically, you want to be spending around £200-£300 for a head unit - this will get you a head unit that will control all of your speakers, including your sub, but it will control your sub SEPERATELY and take the bass out of the door speakers. That is the key.

What you need to be doing, is taking all the bass out of the door speakers and parcel shelf speakers and transferring the bass to the sub ALONE. The 13cm JBL GTO's you have in your doors/parcel shelf aren't big enough/weren't designed to take low frequencies - they can bash out all the mid/high frequencies all day long but when you push bass through them they will distort - as what is happening when you play Metallica's "One". What I have described here is called the "crossover". The crossover point in the EQ range where one speaker stops and another one starts.

Then when you have your stereo, you can tell the sub what you want it to do, and tune your EQ range to suit the music of your choice. My pioneer 8600 has a multi-band EQ, and crossover points that control all 5 outputs. This is why you'll never hear the wrong frequency through the wrong speaker. This will allow you to take your speakers to the maximum capabilities and before they distort.


There are lots of different set-ups you can use for bass speakers: ported, sealed, band-pass etc etc... The best box for metal would be a ported box as a sealed box gives you delayed bass but you can really feel it. A ported box will be more punchy. It also makes a huge difference where you place the box too. In a carlton it's best to place the box directly behind the seats, facing backwards. You get more bass from the back of a speaker than you do from the front. Motorworld do a good range of budget bass speakers. I got a twin 10" bandpass box and 800w amp a while back for just under £200.

I've had to go down a completely different route since I had the LPG fitted. You've seen my set-up - 3x 10" JBL's in the parcel shelf, making the whole boot act as the sound resonation chamber... this isn't the best in the world but it look great and it gives me room in the boot for the LPG tank.

HTH

[carlton_mad]

if you want real quality check out http://www.nakamichi.com/home.html

[Pedro]

Thanks Guys!

Matt - even a complete dunce (drummer, remember!) like me can understand what you put. It actually makes sense. Yeah, I know the JVC ain't up to much, but didn't wanna go head first and buy summat else without knowing what I needed.

So I need Pioneer head unit and a ported bass box in the boot then.

Carlton Mad - that's way above my head, mate. But thanks all the same!

[carlton_mad]

its out of my price range too it is quality though their tape decks sound almost as good as cd and the cheapest one they did when i looked for the first time was around the 200 quid mark for a tape deck!!!!!!!!!! manual tuner etc

[bstardchild]

Make way - DJ geek coming through..................

<snip>

HTH

I can see we need to have a chat about this at Mimms - have 2 x amps, Big sub - not ported, Upgraded speakers for all corners of the car and a shed load of high quality flex

Not a bloody clue where to start with the install!!!

And not a clue what the sort of music I like would sound in a car equipped with it all!!!!

but if I bring my favorite CD can we play it in your car?

[bstardchild]

PS - I'm not admitting publicly the artist or album 

[colonelk]

PS - I'm not admitting publicly the artist or album 

Ah go on! How bad could it be? 

[Pedro]

Make way - DJ geek coming through..................

<snip>

HTH

I can see we need to have a chat about this at Mimms - have 2 x amps, Big sub - not ported, Upgraded speakers for all corners of the car and a shed load of high quality flex

Not a bloody clue where to start with the install!!!

And not a clue what the sort of music I like would sound in a car equipped with it all!!!!

but if I bring my favorite CD can we play it in your car?

Have to say that Matt's system sounds good to me.
I know my ears might me a bit shattered after spending a good few years sat next of 20,000 watts of Marshall JCM amplification set at eleven, but I can still tell what sounds good and what doesn't.


And Matt's sounds good!

[Matt]

Make way - DJ geek coming through..................

<snip>

HTH

I can see we need to have a chat about this at Mimms - have 2 x amps, Big sub - not ported, Upgraded speakers for all corners of the car and a shed load of high quality flex

Not a bloody clue where to start with the install!!!

And not a clue what the sort of music I like would sound in a car equipped with it all!!!!

but if I bring my favorite CD can we play it in your car?

I'll tell you what I know and what I recommend but I'm certainly no expert....

What car is it to go in?

Presuming that the second amp is intended for the corner speakers: depending on the stereo, you probably won't need to amplify the 4 corner speakers - I haven't found the need to yet, even with 3 subs - I don't really want to blow my head up.... most newish stereos have decent built in amplifiers - 4 x 40w/50w is ample. If it's a 4 x 50w head unit it will mean that all 4 of your speakers is getting 50watts each, meaning that your head unit has a 200w amp built in, which for corner speakers is enough as you don't need much. Bass is the main culprit for stealing wattage and you don't want bass to come through your corner speakers if you have a sub.

OK so you have 1 sub. The amp that powers this will need to be either monoblock (single output) or a 2 channel amp that's bridgeable (again - single output). Otherwise you'll only be using the amp to half it's capabilities but still working it to the max. Also, look what rating the amp (and the sub) is and at how many ohms that rating is at. The lower the ohm rating the more power it can put out. But you have to wire subs up in series to lower their ohm rating, if they can handle it.
Simply put:
If a sub is rated at 4ohms, then you can lower the sub's ohm rating down to 2ohms by wiring another sub in parallel, like a daisychain.
If an amp is rated at 2000watts, it will probably be 2000w at 1ohm (sometimes unstable), 1000w at 2ohms and about 500w at 4ohms.
To get the amp and the subs working to their full potential (albeit rather unstable, depending on your amp and subs), you need to wire 2x 2ohm subs up to a single output of the amp, in series:

Amp (bridged/monoblock - single output) -----------> sub ----------> sub

This will bring your amp and your subs down to 1ohm and therefore the amp will be able to output 2000w to 2x 1000w subs - then the amp and subs will be working at their full potential

But in your case Ian - I'm guessing that the sub will be rated at 4ohms, and whatever the amp says it can handle, it will be rated at maximum - always read the small print in the instructions to see what the amp outputs are at different ohm levels to suit your subs and your setup. (ps - not too sure if you bridge an amp whether it will bring the ohm rating down.)

Is the sub going in a box or in a shelf or what? Presuming it's going in a box and if you're saying it's not ported I'm guessing it's a sealed box. Does the box need to ever come out of the car? (You can fit quick release systems to it for power and signal and bolt the amp to the box for when you need the space or when you need to save weight for a track ) If it's a sealed box then obviously there's no port so you can't do the trick of pointing the port in a certain direction to get the best effect - ie bouncing the bass waves off the boot. As stated in the previous post - bass is louder behind the speaker so by pointing the speaker away from the passengers you will get the best benifits. If it is pointing sideways it will not reach the passengers very well and you will loose the desired effect. Also, if it's in a shelf, the bigger the resonation chamber, the better really. Boxes are usually wedge shaped because they are kinda tuned to get the maximum effect out of a certain size speaker, but with a shelf you can't do that so you just use your whole boot space as the resonation chamber. There is also another trick of reversing the sub so the magnet is pointing outwards. This is only effective if you have a stereo that will reverse the signal for the sub and use a sub that is designed for that purpose. Never tried or heard one so can't comment on this.

The main pig of a job is to run the power cable through your bulkhead from your battery to the amp. It needs to be good quality cable and it needs an inline fuse - around 30 amps usually, then the negative can go anywhere onto the bodywork to get a good earth. The signal cables (twin RCA) will usually have the trigger wire built into the whoe thing - this is the same trigger wire that tells the aeriel to turn on/go up. If you havn't got a signal wire, you can piggyback off the aeriel wire and it will do the same thing - simply turn the amps on using the main power cables that go directly to your amp, otherwise you will drain your battery in a matter of half an hour or so.


Feel free to try the CD in my car at Mimms mate, it sounds OK, but only 2 subs are working at the mo so not up to full potential, yet. I might have a go at fitting the other amp this week. (PS - I'll let you all know what the CD is when I've heard it )

The other thing you need to understand when you're running things rather loud is that every recording of every song is different. Some tracks will have lots of bass and some will have very little - this is purely down to the sound engineer that recorded the track, the recording studio setup and the type of band/artist it is - there is nothing you can do about that! But...... this is where the seperate sub control on the stereo comes in handy. If a track has lots of bass, you can turn the subs down at the press of a few buttons.

[HMK]

Good post there, Matt, but I have to disagree on one point - or perhaps I'm misunderstanding something!?

When you talk about speakers being in 'series', do you actually mean in 'parallel'?

If you have a single speaker of 4 ohm impedance, the output stage of the amplifier will see this as 4 ohms.

If you have 2 speakers, each of 4 ohm impedance, & you connect them as in a 'daisy chain', this is connecting them in series, then the amplifier output stage will see an 8 ohm impedance. You describe this as being 2 ohms??

If you have 2 speakers, each of 4 ohm impedance, & you connect them one across the other, ie, in 'parallel', then the output stage of the amplifier will see a 2 ohm impedance. You were saying that they need to be in series to achieve this impedance drop??

One thing that is very important, is to make sure that the speakers are ALL working in 'phase' with each other. They are usually marked with a (+ & -) on their terminals, but just to be sure, I always 'flash' a small DC voltage source (ie, a PP3 9 volt battery) across the terminals to check in which direction the cone moves. This needs to be done with each speaker to check that the polarity is the same way round on them all (this mainly applies if you are using a mix & match of different speakers from different sources).

[Matt]

Impedence has never been a strong point for me... From what I understand:

if you connect your subs in this way:

|---- (+) SUB (-) ---- |
|                              |
|                              |
|                              |
|---- (+) SUB (-) ---- |
|                              |
|                              |
|                              |
|---- (+) AMP (-) ----|

Then that will reduce the ohm rating - I see this as series, but I may have it the wrong way round.

If you wire your subs in this way:


|---- (+) AMP (-) ---- (+) SUB (-) ---- (+) SUB (-) ----|
|                                                                             |
|----------------------------------------------------------------|

It will raise the impedence?

I thought that was parallel - but thinking about it it even looks like series when I put the diagram down!

Oh well, I've got 1 channel per sub anyway so bollox to it - I'm alright jack.........

[bigjohn1969]

When i put this together the script was quality and stupid amounts of bass when required.
The quality bit was quite easy,good quality speakers and good quality wiring.
The insane amount of bass took along time to perfect,zero guage cable three 600amp batteries 3 1000 farad power caps.
2 500watt rms amps running at 4ohm,but to get really silly power out of each amp they could drop to 1 ohm at the flick of a switch!!
But you need to then cool the amps because most amps can handle 1 ohm but the problem then becomes heat,the lower the resistance the hotter the amp,mine would run all day at 4 ohm and the fry an egg in 1 minute at 1 ohm,so i only used 1 ohm for competions etc.
Both subs had a large domestic switch on the side to handle the power then you could switch the subs from 4 ohm to 1 ohm.
I could do this because the subs were 2 ohm dual voice coil jl 15 w3`s.
But at the end of the day its all about what you are willing to spend,to do my whole install cost me £10,000 ouch!!!!
I loved it to bits and had three good years and went to many shows and drownded out many poxy installs in saxo/punto crap.

But its all upto your own personal choice,listen to other peoples installs and make your own mind up,a good quality audio dealer should let you try out different types of sub i know base systems in blackburn will let you try different types as long as you have your own amp wired in.
I currently have a tantrum 500.2 bridged amp running a poxy 10"crap sub and its killing it,the sub is flapping all over the place.
Just cant be bothered with audio anymore...............bigjohn

[Pedro]

Impedence has never been a strong point for me... From what I understand:

if you connect your subs in this way:

|---- (+) SUB (-) ---- |
|                              |
|                              |
|                              |
|---- (+) SUB (-) ---- |
|                              |
|                              |
|                              |
|---- (+) AMP (-) ----|

Then that will reduce the ohm rating - I see this as series, but I may have it the wrong way round.

That's definitely parallel, matey.

The other was definitely in series.

Just basic electrics.

[colonelk]

FYI

for series

R_total = R₁ + R₂ + ........

for parallel

1 / R_total = (1 / R₁) + (1 / R₂) + ...........

IIRC from me leccy days!

so for parrallell, if you have two 4 ohm loads in parallel, the resitance will be 2 ohms
if you have four 4 ohm loads in parallel, the resistance will be 1 ohm

I say resistance, as IIRC impedance gets a lot more complex as things change depending on what frequency is going through the speaker, so best to stick to the base ratings for simplicity. Its been a long time, but Im sure the basic calculations are correct if nothing else!

[HMK]

You're all correct chaps - it is parallel & not series.

Perhaps Matt could edit his post & change it to 'parallel', if he wanted to, as it's a very informative post otherwise..........trouble is, it'll make these posts since seem silly to anyone who reads them afterwards

[bigjohn1969]

Now of course if you have 2 dual voice coil subs and 1 amp you can have.......SERIES-PARALLEL.......
And you can do this with 3 or more subs.
jm2pw
bigjohn

[blippi]

You're all correct chaps - it is parallel & not series.

Perhaps Matt could edit his post & change it to 'parallel', if he wanted to, as it's a very informative post otherwise..........trouble is, it'll make these posts since seem silly to anyone who reads them afterwards

or perhaps he could copy an paste it in2 the how2 section? or allow some1 else 2?