door speakers and amp setup

[fla 9]

Ive got Lotus PW165 speakers in my doorcards (in audioscape pods) and i will be looking to install some new tweeters in the dash, using some crossovers i bought about 2 years back (as usual :))

 

The frequency range of the Lotus' seems to be from 50Hz, so if the signal is amped would this be sufficinet to have a nice warm bass? Not looking for anything bone shaking, i'm hoping to avoid putting a sub in the boot.

 

Also, to rewire, is the following correct?

 

Head unit wires from multi-connector - cut the two that go to the dash speakers, solder new ones on, run these to crossover then one pair to new tweeters. RCA to amp in boot and then from boot to door speakers. This way would mean that the door speakers would only work with the amp on?

 

If i dont use the amp, then it would be

Head unit to crossover, Crossover to door speaker?

 

Finally, if i get a small sub then it would be:

 

head unit to crossover, crossover output to tweeter, crossover second output to door speaker, RCA to amp, amp to subwoofer?

 

To avoid interference, the rca cable should be run away from the +ve to the amp in the boot? So one goes down the side of the car the other through the middle?

 

I'm sure these are all basic questions to you audiophiles though!

 

thanks

[leon263 0]

If you have a look at the crossovers you will see that there are two input terminals (+ and -), tweeter outputs (+ and -), woofer (door speaker) outputs

(+ and -) and, if you are using the Diamond Audio crossovers you bought from me, RAF (rear ambient fill) outputs (+ and -)

In a normal system the tweeters and woofers would be wired to the outputs on the crossovers. In the case of the Diamond Audio crossover, the rear speakers could also be wired to the crossover. Normally the input signal to the crossover would come from an amp in the boot, the crossover would do it's job and send the relevant frequencies to the relevant speakers. You could supply the input signal to the crossover by using the front speaker leads from the head unit but you would be doing the speakers no justice due to the low power output of the head unit. I've never seen it done and I'd really recommend the use of a multi channel amp in the boot.

If there is no RAF output on the crossover the rear speakers will run off the head unit as usual while the front end speakers will run off the amp.

You should be looking at using a three or four channel amp which would allow for the future use of a sub.

In the case of a three channel amp you would wire the crossovers to outputs one and two on the amp and use channel three to drive a sub if required.

In the case of a four channel amp, use channels one and two as above for the front end and then bridge channels three and four to drive the sub. Bridging merely means using the + output on channel three and the - output on channel four. The terminals will be clearly marked on the amp should you wish to use it in bridged mode.

Installing an amp is simplicity. Run a fused 4 gauge power cable directly from the battery to the amp, earth the amp in the boot or under the rear seat to any handy bolt, run a 'remote on' wire from the back of the head unit to the amp. This tells the amp to switch on when you turn the head unit on. The 'remote on' cable on the back of the head unit will be blue with a white trace and should be clearly labelled. Run an RCA cable from the back of the head unit to the amp to supply the audio signal. Depending on the quality of your head unit there may be front, front and rear or front, rear and sub woofer RCA outputs. In a basic, no sub, set up use the front output.

As you mentioned, keep the power cable well away from the RCA cable to avoid interference and if you buy a four gauge amp wiring kit, it will contain everything you need.

 

Any question ............ fire away.

Edited July 11, 2014 by leon263

[fla 9]

many thanks for the comprehensive reply, and yes we're talking about the Diamond Audio ones from you. I'll check the amp connections and get back to you - its a Rockford Fosgate, so should be more than adequate for my use.

[fla 9]

Ive got a parrot hands free installed which is connected via one of the multi connectors. Would this still operate correctly if I use the main signal from the rca outputs?

[leon263 0]

Shouldn't be a problem.

[Stonejag 10]

I'm surprised you would need more than the 25-45W per channel you get out of a decent head unit. Does it really make that much difference?

 

I'm using Rainbow 6" drivers in Audioscape pods with 3" speakers in the dash and stock rear speakers with an Alpine HU, and my ears would be bleeding long before I get any distortion from the internal amp.

 

Stone

[fla 9]

Hmm OK. Leon263 do the crossovers definitely need power to filter properly or as Stonejag says the hu output should be adequate? I just want a good soundstage no ear splitting performance or bone-shaking bass!

I'm sure my setup will be a compromise but again as stone says would it make a significant difference? My current hu only has one set of rca outputs (for the sub).

Thanks

[leon263 0]

Powering the crossovers from the head unit would certainly work OK. In the original set up on the Corrado, the power from the head unit goes firstly to the dash mounted tweeters and from there down to the doors. You will find two connectors on the back of the dash mounted tweeter, one in and one out. To avoid cutting any cables you could just extend the cable from the head unit to the tweeter and run it into the crossover and from there runs cables to your new tweeters and woofers.

[Stonejag 10]

If it's not a powered crossover it's almost always just a pair of small RLC networks to form two simple passive filters. One filters out high frequencies (to feed the door woofer) and one filters out low frequencies (to feed the tweeter) - both are just fed from the amplified output from the HU. The standard speakers have fairly narrow frequency response so they form their own simple crossover by just feeding the same signal into both - if you use better speakers than stock (or very high volumes) then you may not want to feed lots of bass into a tweeter because its attempt to output it can interfere with the sound produced by the dedicated bass speakers, and vice versa.

 

If you use an external amp you're putting an unamplified line-level signal from the head unit to wherever your amp is and letting that do the job instead of the amp built into the HU. You can get a lot more power output (or another way of thinking about it is that you have more overhead before the amp saturates so that you don't get clipping) BUT you have to run power and audio into the boot, and a long run makes it more likely to pick up interference since it's not amplified... Some argue that corners are cut in making an amp that will fit into a single DIN slot, so an external amp will give higher quality - and they're not entirely wrong. That said in any modern stereo it's all done digitally so provided you're not at crazy volumes you won't get clipping or distortion anyway. Decent speakers with a crossover matched to their frequency response are more than adequate IMO - I actually have Rainbow tweeters and crossovers which I got with the Audioscape pods and never bothered fitting them, as the improvement just from having bigger door speakers was so marked.

 

Suck it and see before you sacrifice your boot space! The one big improvement from an external amp is for driving a sub in the boot, and most decent head units have a dedicated unamplified sub output for driving one anyway. Do use decent spec shielded cable because crackly bass is really irritating.

 

Stone

[fla 9]

just coming back to this one - i'm part way through refitting the ICE in my car. At this stage i've not used an external amp, but have teh cables in place should this be required, and i think it will. The sound does sound a bit thin - i've got a Kenwood 5541 HU going to the crossovers and then the two outputs are connected to each of the tweeters and door speakers.

 

Now, if I want to use the amp in the boot for the door speakers, is this correct?:

 

HU to amp via rca leads

Amp wired to crossovers to supply feed signal

Outputs to tweeters and door speakers remain as they are.

[fla 9]

just to check that the above (last post) is correct re the amp to the crossovers?

[Jamie 1]

Yeah that's correct Hasan - the speaker terminals on the amp go to the inputs on the crossovers, then the outputs go to your speakers, one pair to the mid, one pair to the tweeters

[fla 9]

Great, thanks for that jamie

[fla 9]

slow progress as ever.

 

The amp will be screwed to the back seat, so where should the fuse be mounted? Should this be by the amp or in the engine bay near the battery? Also the ground - where should this be fitted? I am assuming the seat bracket bolt as this looks fairly meaty. Just remove paint and install, covering with grease to prevent corrosion, not that there should be any inside?

[Jamie 1]

slow progress as ever.

 

The amp will be screwed to the back seat, so where should the fuse be mounted? Should this be by the amp or in the engine bay near the battery? Also the ground - where should this be fitted? I am assuming the seat bracket bolt as this looks fairly meaty. Just remove paint and install, covering with grease to prevent corrosion, not that there should be any inside?

 

Fuse as close to the battery as possible (certainly within 12") and the earth as short as possible. Again less than a foot if possible.

[fla 9]

Thanks Jamie, quick help as always.

[Jamie 1]

Thanks Jamie, quick help as always.

 

Anytime mate :)

[leon263 0]

Don't forget that you will need a 'remote on' wire from the rear of the head unit down to the 'remote on' terminal on the amp. You should find a 'remote on' wire on the back of the head unit, normally blue with a white stripe. Basically, it sends a small current from the head unit to the amp to tell it to switch on when you switch the head unit on.

Edited March 30, 2015 by leon263

[fla 9]

I've recently bought an 8" bass tube for the boot as the door pods really didnt seem to improve the sound stage for me.

I'm looking at two setup options, bearing in mind i have a two channel amp:

 

1. Run the door speakers and tweeters direct from the head via the crossover and power just the sub from the amp

2. Run all the speakers through the amp - is this even possible with a 2-channel amp? If not lets just look at option 1.

 

Assuming 1 is ok, how should the sub be wired to the amp? A diagram would be great. Plus setting the filters etc.

Finally, what are simple suggested ways of anchoring the sub in the boot?

 

Many thanks

[g0ldf1ng3r 15]

hi m8

 

difficult to say, more info would help.....

 

what RMS output has the head unit per channel?

what RMS rating are the door speakers & tweeters & are they a 'component' setup?

have you any rear speakers & what RMS rating?

what RMS rating is your amp in each mode?

 

the above info will allow you to decide if the head unit is powerful enough to run the door speakers (& rears if reqd) OR if the speakers are high enough rated to cope with being run off the amp

 

TBH unless you're running crazy kit id probably say option 1 is more than suffice m8

 

EG in mine I have sony head unit with 4*52watt RMS which I use to power my front door infinity kappa's, 50w RMS each, & infinity kappa 6*9's in the rear, 110w RMS each. I then have a small sub running off an amp

 

regarding wiring, it depends on your amp / sub location (IE both in the same area). for ease my amp is screwed to my sub box, which doesn't need securing as its so damn heavy

 

you will then need RCA cables to go from head unit to amp & also a 'remote' wire from head unit to amp, this is what turns the amp on when the head unit turns on

 

power the amp via a fused power lead to the battery & find a nice earth for the amp in the boot (you can get an amp fitting kit from Halfords etc which includes chunky power & earth leads etc)

 

then connect the sub leads to the amp & bass is your aunty

 

in terms of setup it will depend on what filters you have & if you are using passive or active crossovers?

 

have you ever done a complete sub install? (sorry if that is a naïve question Hasan)

 

hopefully that will make some kind of sense of it all

 

EDIT: sorry if I have repeated anything, I didn't read the thread in full

[fla 9]

good info thanks. No not done an amp install before.

I had wired the amp to the crossovers at the front and then to the door speakers. But like you say i'll connect the head unit directly and just use the amp for the sub. As its a two channel amp, how is this wired to a single sub? Presumably some way of linking the right and left channels?

 

 

I've just bought a Pioneer head unit, 4x52W and have got the Allseas speakers in Audioscape pods. The crossovers are passive.

[g0ldf1ng3r 15]

good info thanks. No not done an amp install before.

I had wired the amp to the crossovers at the front and then to the door speakers. But like you say i'll connect the head unit directly and just use the amp for the sub. As its a two channel amp, how is this wired to a single sub? Presumably some way of linking the right and left channels?

 

 

I've just bought a Pioneer head unit, 4x52W and have got the Allseas speakers in Audioscape pods. The crossovers are passive.

 

cool, glad it made sense

 

head unit will be ok for your door speakers & rears if you have them

 

ive not had component speakers before, IE where you have a 2 way speaker & a separate tweeter, so unsure of their connections but would hope/imagine they still only take up 2 channels for the front & leave you 2 channels for the rear

 

IIRC you would set the amp into 'mono' mode as the sub does not need a stereo feed & I think it would put itself into 'single channel' rather than 'dual channel' depending on what you connect to it. IE if you only connect the RCA leads & set to mono & do not connect any other outputs

 

what amp is it? I can check for a diagram online

 

do you have rear speakers or using the factory 6*4's?

 

I have tried various setups over the years of rado ownership & other cars & though I know some people do not like cutting their parcel shelf audio output really does need 6*9's in the rear. personally I always re-trim my parcel shelf with proper acoustic carpet, not the cloth as its too thin & sags over time, & like the look it gives

 

if you run decent door speakers with just a sub then you may get the bass you wish for but you are going to loose out majorly in mid range

 

have you got an amp fitting kit I mentioned? I think they may include a basic connectivity diagram

 

the passive crossovers simply connect between the head unit output & the speaker itself. those on my front kappa's are hard wired to the speaker & are slotted behind the door pod with some double sided tape

[fla 9]

yes got fitting kit and it has a basic installation diagram. I missed the obvious (which you didnt!), and downloaded the manual for the amp (Rockford Fosgate Punch 120a). So wiring will be across the +ve left and -ve right channels to the sub.

 

I'll be back for sure with further basic questions, like setting up the gain etc. Thanks for your help.

[g0ldf1ng3r 15]

yes got fitting kit and it has a basic installation diagram. I missed the obvious (which you didnt!), and downloaded the manual for the amp (Rockford Fosgate Punch 120a). So wiring will be across the +ve left and -ve right channels to the sub.

 

I'll be back for sure with further basic questions, like setting up the gain etc. Thanks for your help.

 

my pleasure Hasan

 

good luck & give me a shout if you need :)

[fla 9]

Well i'm back on this thread again!  Goes to show my lack of ICE knowledge...

 

Anyway, in the interest of saving space i have removed the bass tube and wired the amp to the crossovers and then to the front speakers.  The rears are direct to the head unit.

 

So now with regards to setting up the door components and tweeters, what details do i need to dig out in terms of high pass and low pass filters?  What about setting up the amp?  The amp is a kenwood kac ps100.  Trying to avoid blowing the speakers but i'd like some warm bass