JL Audio Sub / Amp question

[Rams 0]

Just bought a G4500 Amplifier

 

http://www.safensound.co.uk/jlaudiojlaudiog4500500w4channelamplifier-p-1251.html?utm_campaign=google-simple&utm_medium=product_search&utm_source=google-simple

 

Wanting to run a JL Sub, 10 or 12 inch and some components up front. Can I run 2 channels to the sub and 2 channels to the components and does anyone see any issues with what I plan to do?

 

Also, what sort of sub should I look for to go with the 500 w amp. Quite like to stick with JL and keep everything in the same make.

 

Budget wise, max £300 for a sub and box.

 

I will do the components when my new dash arrives.

 

Cheers peops

Edited March 2, 2011 by Rams

[junkie 0]

Yes you can run components and a sub from the amp.

 

You should bridge channels 3 &4 to the sub, this means you run negative from either channel 3 or 4 and positive from either 3 or 4. Or possibly if using a dual voice coil sub you may be able to use both plus and neg from both 3 & 4. But then you can also wire a dual voice coil with the 1st scenario and link plus on one coil to neg on other. Keeping up so far?

But if going dual voice coil you need the lower ohm voice coils so the amp sees the correct ohm loading so as to not overload the amp of going single voice coil then you need the 4 ohm, I think the jl sub single coil is 3 ohm or something round there. Reason for dual is more power handling for that sub, double the power and double the output but bass is about moving air so it's not like having 2 subs. It may also give better control of the sub so should in theory "sound" better. £300 will get a decent jl w3 and sealed box and I would go for a 10" dual voice coil personally for more punch and tighter faster bass response as opposed to lower frequency response due to the electronic music I listen to I had the 12 jl but ran off a 1000.1 Phoenix gold amp with bass cube and people couldn't believe I only had a single twelve in the boot, click my sig link for pics of it.

 

Good luck lol.

[dogger 10]

If you are using a JL amplifier the impedance of the speaker/voice coils won't increase or decrease the power output. It will produce the same amount of power within its safe impedance range on its specs. Dual voice coils won't double the output. The main reason for dual voice coils has to do with more flexibility with wiring up subwoofers to that amp.

 

Check the specs on the JL HD amps. Notice the power output of the amp is the same even when the impedance drops. Alpine PDX amps are like this too. http://mobile.jlaudio.com/products_amps.php?amp_id=482

 

To understand dual voice coil speakers this will help as well. http://mobile.jlaudio.com/support_pages.php?page_id=163

 

If you look at JL's site and look at the power handling range for their subwoofers. You want a speaker that safely handles 500 watts than find a speaker in the size you want that does. A 10W6 or 12W6 would be perfect but they may not fit your budget as well.

[junkie 0]

By doubling the power you should double the output db which is only 3db. Not saying it's a huge audible difference.

 

I used the jl slash series before the Phoenix gold.

 

Although the amp will do the same power regardless of the ohm load seen at the amp you still do need to match it for what the aMp sees

[Rams 0]

Thanks chaps for replies, ordered the 10w6 JL Sub from the states and a JL Sub box to suit. I took your advice on going for a better quality sub. So, amp wires already installed. 4 gage power cable, gold rca's, just need the connector block once I hook it up to the battery. I 've left enough length ready and wrapped around the battery for now.

 

I also need to take a power supply and find an adaptor for the standard aerial as mine is smoothed over. I bought an after market aerial with booster so I can have radio, in the rare event I listen to radio.

 

When I connect power cable to battery via a connector, what sort of fuse size should I be looking at? Also, will I need another splitter type of block to step down the 4 gage into the amp?

 

As you can tell, im a bit rusty with the stereos systems.... You all sound like you know your ice! Cheers again

[dogger 10]

By doubling the power you should double the output db which is only 3db. Not saying it's a huge audible difference.

 

I used the jl slash series before the Phoenix gold.

 

Although the amp will do the same power regardless of the ohm load seen at the amp you still do need to match it for what the aMp sees

 

 

If in fact you were increasing the audible output by 3db that would be huge and very noticeable. But you aren't. If you are using a amplifier like a JL, you won't increase output, wattage, by lowering the impedance on the amp. You only need to keep the impedance within the safe range that JL rates it. Which is 1.5-4 ohms. The Slash series are the same as the HD and output remains the same no matter what the impedance is.

 

 

Rams, you should use the proper fuse at the battery recommended by the amplifier manufacturer. Why would you need a splitter to step down the power wire to your amplifier? What amp are you using?

[junkie 0]

You are dying what I'm trying to say poorly as in certain points you agree with me as I do you.

 

I'm right your wrong so ner ner ne ner ner

[Rams 0]

are you saying my amp is not up to the task of the sub? The g4500 is what I have bought. Its second hand but sold as being never used just doesnt have packaging on ebay. If its not the correct amp, I can always sell it as I got it for half the price of its RRP. Or it just needs setting up correctly so that it works as best it can for the amp I bought?

Will the 4 gage fit straight into my amp? I recall many years ago when I had a set up in the golf that I used a reducer as the cable was too fat to go into the amp. Its either 4 gage or 2 gage, need to double check.

 

Noted about the fuse, will contact them and see what they recommend and a suitable fuse holder.

Ta

[junkie 0]

Not sure who your asking but no the amp is fine mate.

 

You ideally want to run the largest it can accommodate so if it's 4 gauge connection on the amp just run it straight in if you have 4 gauge. If it say accepted 8 max then run the 4 into a block and downsize to 4. But don't run say 4 into a block and then upside to say 0 if it will accept 0.

[junkie 0]

Ah iPhone constantly spelling for me. So that's also downsize to 8

[Rams 0]

Ok ta, Once the amp arrives I will see if the 4 gage fits straight in.

[dogger 10]

I'm not sure where I am wrong. Sorry I forgot the lower series of JL amps have unregulated power supplies. Still the output of the amp does not double in power when going from 8 ohm load to a 4 ohm load. In order to gain a 3db increase in output you would need to double the wattage of the amp. The G4500 is rated at 160W RMS at 8 ohms and 250W RMS at 4 ohms. Far from double and far from +3db.

 

The G4500 accepts a 4 gauge and is the minimum recommended gauge wire specified by JL. Running a larger gauge wire and reducing it anywhere along the chain would defeat the purpose of using larger gauge wire directly to that amp.

 

To the Op that amp is not a good fit for a JL 10W6. For one the 10W6 is a dual 4 ohm speaker and that amp can only do 4 ohms bridged. So you would have to run it at 8 ohms with a dual 4 ohm subwoofer and your power output at that impedance is going to be 160 watts at best if your alternator ever put out 14.4 volts. Most likely the amp will see 13.5 volts so you will have even less power. You bought a great subwoofer but it needs a higher output amp. You really need around 500 watts to get your monies worth out of that speaker.

[Rams 0]

Fiddlesticks,

The amp arrived today as well!

So, do I need a mono amp thats at least 500 watts rms?

 

Would it be man enough then to power some components? I havent bought them yet as working out what im going to do with the speaker size/doorcard mod?

 

What sort of AMP do you suggest to run the sub? I would like to stick with the JL brand where possible and the sub should arrive tomorrow. I cant buy a JL box anywhere, so I would like my friend who works at Sunseeker to make me one. Hes great with this type of thing and dimensions are available on line but any tips of material to use, i.e the grade or thickness of the mdf etc?

 

Rams

[junkie 0]

I'm gonna keep out of this as I'm obviously not coming across right. I am actually saying you are more right than me and I'm trying to be sarcastic and not quite so serious son.

 

You constantly misinterpret what I'm trying to say. I never suggest running 0gauge and downsizing to 4 gauge I was saying if he had bought 0 as an exams and the amp only took 4 then to save costs buy an power distribution block as more than likely another amp would be added anyway down the line.

 

Never even looked at the amp specs at all yet and I'm just generalising on theory yes maybe slightly too much but it's easier to understand to noobs on ice issues.

[junkie 0]

Like I said a 10 w3 would prob be good. Look on eBay for a slash series 500.1 they go pretty cheap and are awesome keeping it with jl

[dogger 10]

I wasn't talking to you, junkie, in my last post. Just clarifying some of what you and the OP have been discussing. I didn't check the specs on that amp before posting earlier but once I saw them I was trying to clarify the power output as it truly is. Which is not enough for the sub being used. And not going to be a +3db gain.

 

The Slash 500/1 is good or even the XD600/1. The G4500 for components would mean you need speakers that have a high power rating. If you get a good set of components with that amp and subwoofer, it will be loud and clean. I agree for the G4500 the 10W3 would have been perfect. It would have saved you some money too and its a great sounding subwoofer. W6 is nice but needs power to do so.

 

As far as a box is concerned use at least 3/4" MDF and build it as tight as possible. I would suggest a sealed box over ported. I've built several different set ups in Corrados and subwoofer boxes up against the back seat with the speaker firing rearward towards the hatch sounded best. If you can mount the box to the car well it helps even more.

 

Having multiple amps in a Corrado is fun for installation since there aren't good places to install them. With one amp you can at least mount it on your speaker box.