Someone please school me!

[BigFas]

This ICE project is doing my head in.

Custom enclosure has been bought and will be picked up tonight.
Subs have also been bought and will be picked up on Saturday morning.

I went for 2 JL Audio w3d2 10inch subs. They're a discontinued model, but they were brand new and were an unbeatable price so I went for them.

No I just need an amp to power them. Which is where my brain is hurting.

What's confusing me is

a) wiring. What does it mean when people say wire the subs in paralell or series
b) Inputs : what's the difference between hi-level and low level inputs?
c) The amp I'm looking at has the following spec

990W x 1 (Max)
550W x 1 RMS [2 Ω @14.4V (1%THD)]
275W x 1 RMS [4 Ω @14.4V (1%THD)]
425W x 1 RMS [2 Ω @12V (1%THD)]
225W x 1 RMS [4 Ω @12V (1%THD)]
8.5V Input Capability
Buffered PreOut
Fully Digital Class-D Technology
Digital Control Centre with LED Information Display (Temperature, Voltage, Current)
Bass Engine DSP (Parametric EQ, Crossover,Time Correction, Phase Control, Subsonic Filter, Bass Compensation)
Integrated Wire Covers
Variable Turn-On Delay
Memory Preset
Thermal Management
Safe Mode
Amplifier link / Remote Amplifier Control Centre Ready

Which line do I need to read which says, yes, this amp will satisfactorily power the 2 subs.

Someone school me in EASY english :D

[Defector]

Right, im no expert but ill have a go.

a) Parrellel means you wire them up with both subs '+' going to the '+' on amp, and both subs '-' going to '-' on amp.

http://www.colomar.com/Shavano/spkr_p.gif

Running in parrellel means the resistance will drop ie (2 x 8ohms will produce a 4ohm load)

Series means you 'daisy chain' them. You connect one subs '+' to '+' on amp, then connect that subs '-' to the '+' on the next sub, then the second subs '-' to the amp.

http://www.colomar.com/Shavano/spkr_s.gif

Running in series means the resistance will rise ie (2 x 8ohms will produce a 16ohm load)


Bit difficult without diagrams

b) Not sure about this, i think it means:

Hi-level inputs are for tweets and possibly mids, as it has had the low frequencies cut out.

Lo-level is the opposite, connect sub to this. Your going to need to adjust the low-pass filter to make sure that only the really low level stuff goes to the subs, otherwise it sounds crap.

But it could mean you can run two sets of RCAs to the amp, one for the high end and one for low, but i dont think its this because amps only got 1 channel.

c) 225W x 1 RMS [4 Ω @12V (1%THD)]

This tells you that at 4Ω (which your sub is likely to be) and at 12V (which a car is) you can pump out 225W. Which will be enough to give your subs a seeing to. What power are the subs?

[BigFas]

ok, great start. I think I get it.

According to the papework I have, the 10w3d2's have a Power Handling (continous) rating of 250w. Does that sound about right? If that's the case, and the amp is pushing out 225 watts, does that mean the subs will be underpowered? Will that figure be linear for 2 subs? I.e. 225w feeding 2 subs = each sub gets 112.5w each? Or doesn't it work like that?

[Durgesh]

I think High Level Input's refer to input to the amp via speaker cable, rather than using RCA's which much better to use. In your case fas, as most of the wiring is done, we will have to go with high level, ie speaker wire. I don't even think the BMW units have RCA's preout on the back.

Fury, I think you are mixing it up with High Pass and Low Pass filters.

The rest of the stuff looks fine, I would say get a two channel amp, as you are running two subs.

So you want something like 2x500 RMS, that;s what I had, and it kicked hard!

Durgesh

[BigFas]

This is the amp I've been looking at,

http://www.caraudiodirect.co.uk/product_info.php?products_id=3518

Alpine V12 series (their top of the range) at a pretty reasonable price too (I'm sure I can get it cheaper at Tottenham Court Road)

It doesn't say how many channels (or if it does, I'm not edumacated enough to see it)

[Shuriken]

Yeah, it is telling you the number of channels:


225W x 1 RMS [4 Ω @12V (1%THD)]

It's saying it has one channel at 225W RMS, plus all the other stuff.

Shuriken.

[Afif]

ok skimming thru the posts im getting the idea if you run them at parralel theres only a 2ohm total load (2 x 4 ohms will produce 2 ohm load) so this one shud apply right?

425W x 1 RMS [2 Ω @12V (1%THD)]

so half that and each sub is seeing roughly 212 rms. Which isnt to far off the RMS.

Also fas did you take into consideration amount of space in the box? Does it go with the recommended for the subs?

[BigFas]

box is custom made by Prestige audio and yes, the cubic acreage is well suited to the subs

[Afif]

then its all gravy [jam. I was supposed to get my dual 8 inch hook up sorted over the winter! Been put off till easter now cos of the repairs over winter. Ahh well. Something to look forward to :D.

[beacham]

hi,alpine amp is good and will do the job but the JL amps are the way to go,no fancy stuff just sheer power to drive those subs ;)

[Defector]

Fury, I think you are mixing it up with High Pass and Low Pass filters.

Yes, i was. Sorry. :o

Fas, as has been said, you're better off getting a two channel or even a 4 channel which you could bridge. The more powerful the amp the better. Much better to run a amp at half power than buy an amp thats only just enough and have it maxed.

Also, just to make things even more complicated...

If your JL subs are like mine, they have dual voice coils. In which case for optimum sound you can buy a four channel amp, and have each channel powering one of the coils.

...just a thought.

[Durgesh]

I am still not sure if that amp can power both subs, we need to know the full spec of the subs, so we know what Ohm's they are.

Durgesh

[BigFas]

Full spec of Subs right here

[nass]

As your subs are d2's, your most likely wiring configuration for both of them will be to wire each individual sub in parallel so each sub is wired as 1ohm. Then you wire the subs in series to each other so together they will show your amp a 2ohm load. Sounds complicated but its really simple in reality. Give me a shout and i'll help you wire them up.

As your going to have a 2ohm load the line thats most important to you is:
550W x 1 RMS [2 Ω @14.4V (1%THD)] so your subs are be going to get 225 watts rms each. It is true that its better to over power subs than it is to under power subs but the power of the amp is sufficient for your setup.


Also it has been mentioned that it will be better to get a two channel amp to run the subs. I have to disagree with this as there is no difference to the sound that you will get, at the end of the day if a subs getting 550wrms is the same whether its from a two channel amp or a mono amp. The only thing with a two channel amp is that its versataile as you can use it to run speakers as well as your subs. But where the mono amp comes in to its own is that its a class d amp and runs about 80% efficient whereas the 2 channel amp is going to be a class a/b design that is only about 50% efficient. In real terms this means that the class d moo amp is going to be putting a lot less strain on your cars electrical system and you shouldn't experience any light dimming when the bass drops.

Final point about the high level inputs, this just means that you can take a signal from the speaker wires to run the amp. This is not as good quality as running rca's but if your headunit doesnt have an rca output then the fact that the amp can take high level inputs is very usefull to you and will save you a lot of hassle. High level inputs aren't a very common feature on amps so if you haven't got rca outputs other amps may prove to be a bit more hassle to hook up.

Bottom line is that the amp produces sufficient power for your subs and produces most of its output at 2ohms, is a class d amp and is very efficient and will be easy to hook up because of the high level input capability so i would say that the alpine amp is a good choice for your setup.

[beemarman]

check this site out for ideas www.talkaudio.co.uk really good for advise.

[BigFas]

As your subs are d2's, your most likely wiring configuration for both of them will be to wire each individual sub in parallel so each sub is wired as 1ohm. Then you wire the subs in series to each other so together they will show your amp a 2ohm load. Sounds complicated but its really simple in reality. Give me a shout and i'll help you wire them up.

As your going to have a 2ohm load the line thats most important to you is:
550W x 1 RMS [2 Ω @14.4V (1%THD)] so your subs are be going to get 225 watts rms each. It is true that its better to over power subs than it is to under power subs but the power of the amp is sufficient for your setup.


Also it has been mentioned that it will be better to get a two channel amp to run the subs. I have to disagree with this as there is no difference to the sound that you will get, at the end of the day if a subs getting 550wrms is the same whether its from a two channel amp or a mono amp. The only thing with a two channel amp is that its versataile as you can use it to run speakers as well as your subs. But where the mono amp comes in to its own is that its a class d amp and runs about 80% efficient whereas the 2 channel amp is going to be a class a/b design that is only about 50% efficient. In real terms this means that the class d moo amp is going to be putting a lot less strain on your cars electrical system and you shouldn't experience any light dimming when the bass drops.

Final point about the high level inputs, this just means that you can take a signal from the speaker wires to run the amp. This is not as good quality as running rca's but if your headunit doesnt have an rca output then the fact that the amp can take high level inputs is very usefull to you and will save you a lot of hassle. High level inputs aren't a very common feature on amps so if you haven't got rca outputs other amps may prove to be a bit more hassle to hook up.

Bottom line is that the amp produces sufficient power for your subs and produces most of its output at 2ohms, is a class d amp and is very efficient and will be easy to hook up because of the high level input capability so i would say that the alpine amp is a good choice for your setup.

Hey bro, met up with Digs, Tesh and Vik just now and we discussed this at length and what you've said is spot on what we decided.

We've also figured out the amp I'm going for as well. JL Audio e1400D (Nass, do me a favour, check it out on JLaudio.com) we did a quick web check and it has the high level input and as the power to provide my subs so looks like the final piece has just fallen into place. Just need some cash money now

[Ali_]

Nass you Ice geek :p

Fas im getting a little confused bro, why the install if you are flicking her on or is this not happening any more :o

[BigFas]

Nass you Ice geek :p

Fas im getting a little confused bro, why the install if you are flicking her on or is this not happening any more :o

Everything is re-usable and reversible my friend. Even if the car goes tomorrow, I don't lose out, it means I have a ton of bits for the new whip

[Afif]

>.< this is wear u guys are so different. I dont plan to sell the whip. When i get a new one old one going to be passed down to younger sis. She'll be driving by then. No worries on irreversable mods :D.

[Ali_]

Everything is re-usable and reversible my friend. Even if the car goes tomorrow, I don't lose out, it means I have a ton of bits for the new whip

I see i see said the blind man :)