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Basic help with Car Audio (1 Viewer)

loquasagacious

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Rewiring the stock deck would not be required in any situation I can think of.

Assuming that the deck does not have RCA pre-amps (a likely eventuality) then you would simply need to acquire an amp that accepted speaker level inputs, can drive three channels and preferably has seperate crossovers for the channels.

In this scenario you take the wiring from the rear speakers and run it to the amp from the amp you drive the rear speakers and the amp. Obviously with a low crossover on the amp and a neutral(ish) one for the rear speakers.

eg:
HU--->Front Speakers
--->Amp (via rear speaker outputs) ---->rear speakers
---->Sub

Wholesale re-wiring does not occur unless you replace the stock HU in which case it is simply a matter of installing an adapter harness between your new HU and the wiring loom. So in an important sense (unless you're like me and solder the new units harness in because you're working in an old car...and save $20) re-wiring never occurs.

As far as whether a simple speaker upgrade would do the job, given the bass requirements I doubt it - a good measure of what the difference will be is asking yourself is there distortion when I turn my HU all the way up? If there is then new speakers will improve this and enable louder volumes. A more precise measure is to compare the rms output of the HU and the speakers - lets say the speakers are 10w and the HU is 15w (example from my mates lancer pre upgrade), the installation of 30w speakers will only yield a 5w increase in perfomance and hence a HU upgrade is on the cards in order to experience real gains.

My suggestion is amp+sub+new speakers and consider a new HU down the track as installation in a new car may well get messy (and expensive) eg many do not use a standard DIN mount. Furthermore if you lay off the HU now you can take advantage of improvements in HU that are just around the corner, afterall HU are the most fast moving in terms of developement. In a year ipod, usb, mp3 cd, dvd, HD-DVD, etc etc will all be far more mainstream and you can reap those benefits.
 

seremify007

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Thanks for that.. I read what you said :)

I've gotten a few price quotes from various places and they are all under the $850 mark if I use Japanese components (JB: $835 for Pioneer amp/Pioneer sub; Stratty: $850 for mx sub and mx amp; Lifestyle: Can't remember if it was $750 or $850; but I think it was $750.. for Clarion amp/Pioneer sub). I'm inclined to think Lifestyle is the place to go since it seems to have a good reputation and the price is the same as the other places (or $100 less- if only I could find the quotation they gave me).

The other consideration is.. should I spend $400 more and get Rockford Amp and the Punch P2 sub.
 

Qlimax

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loquasagacious said:
Rewiring the stock deck would not be required in any situation I can think of.

Assuming that the deck does not have RCA pre-amps (a likely eventuality) then you would simply need to acquire an amp that accepted speaker level inputs, can drive three channels and preferably has seperate crossovers for the channels.

In this scenario you take the wiring from the rear speakers and run it to the amp from the amp you drive the rear speakers and the amp. Obviously with a low crossover on the amp and a neutral(ish) one for the rear speakers.

eg:
HU--->Front Speakers
--->Amp (via rear speaker outputs) ---->rear speakers
---->Sub

Wholesale re-wiring does not occur unless you replace the stock HU in which case it is simply a matter of installing an adapter harness between your new HU and the wiring loom. So in an important sense (unless you're like me and solder the new units harness in because you're working in an old car...and save $20) re-wiring never occurs.

As far as whether a simple speaker upgrade would do the job, given the bass requirements I doubt it - a good measure of what the difference will be is asking yourself is there distortion when I turn my HU all the way up? If there is then new speakers will improve this and enable louder volumes. A more precise measure is to compare the rms output of the HU and the speakers - lets say the speakers are 10w and the HU is 15w (example from my mates lancer pre upgrade), the installation of 30w speakers will only yield a 5w increase in perfomance and hence a HU upgrade is on the cards in order to experience real gains.

My suggestion is amp+sub+new speakers and consider a new HU down the track as installation in a new car may well get messy (and expensive) eg many do not use a standard DIN mount. Furthermore if you lay off the HU now you can take advantage of improvements in HU that are just around the corner, afterall HU are the most fast moving in terms of developement. In a year ipod, usb, mp3 cd, dvd, HD-DVD, etc etc will all be far more mainstream and you can reap those benefits.
this guy knows what he's taklign about, no fuss, no rudeness, just knowledge.
but just a basic question, i'm quite positive that anything you do besides simply changing the speaker set, if you want to add an amp.. you will still be required to remove the head unit out, to get to the back?

I got a mate of mine who does the way you do and i shouted him a good meal for like 3 hours of work.. you will still require to take apart the console to get the HU out right? i hate all the new civics where you everything is clipped on, one of my clips got broke =(.. but no biggie.

so you're saying you can do it like that.. but for sure the sound quality wont ever be as clear!.. hrmm.. this is why I don't like cars with inbuilt HU's... like the mazda 3!!..
 

seremify007

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Telling me that new civics with clips which breaks... scares me >__> I think I'll let Lifestyle Store do it; they seem pretty pro with installs (judging by their website and what my friends have said).
 
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i really wouldnt bother spending $1000+ just so an extra umph in bass...unless youre one of those people who put their subs on full loud, so everyone in the street can hear you when youre driving nearby.
but by the looks of it, you dont seem like that sorta guy.heh heh.

on another note...i got my stuff installed today. i like what im hearing :):)
as far as i can see.. theres no shotty workmenship...everything was done neatly and nicely- amp screwed to the back of the backseats neatly..wires running freely

and for the audio dudes..
whats this..? i think it was in the amp kit..



EDIT: got another question.
when the bass starts to distort, is it because my amps not good enough...or is it my sub.?
 
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seremify007

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I think that could be either?

As for what the picture is... looks like the thing the guy showed me to prevent a power surge or something damaging my equipment? *shrugs*

I listen to a lot of Chinese pop songs as well as English dance music... but I'd rather have good quality audio than the super loud THUD THUD THUD... The $1150 system at Lifestyle had really smooth/tight bass, whereas the other brands had a lot of.. reverb?
 

loquasagacious

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Qlimax:
Installing an amp using speaker level inputs MAY not need access to the rear of the HU - this depends very much on the car. If the rear speakers are mounted on or somewhere near the parcel shelf then its a matter of disconnecting the wires from the speakers themselves, extending them to the amp and running wire back from the amp to the speakers.

If they are mounted in the rear doors it is far more 'fun' eg in that scenario my recommendation would be to access the rear of the HU run wire from the rear speaker outputs back to the amp (probably in the boot) and then from the amp all the way back to the rear of the HU and connect it to the pre-existing wires that run to the speakers. A pain in the arse by all accounts.

As a note even if you dont have to access the rear of the HU you still need to pull up alot of trim to get the amp wired in.

As far as sound quality obviously RCA is preferable to speaker level but you make do with what you're given, and in a big plus any amp that accepts speaker level inputs will also accept RCA and so when down the track you upgrade the HU you can then start using the RCA connectors and experience a gain in quality.

Too Lazy and Seremify:
As far as what that is - it is a standard 8gauge fuse (probably 60amps), - it prevents current surges destroying your amp.

As far as quality of workmanship it is actually quite poor:
You can seen that the wiring is actually doubling back on itself (eg the wire at the front of the fuse is going to the back of the car and vice versa) which is messy and poor form but also compromises performance.
Also the placement is poor - that area of the car shifts so it isnt 100% stable but more importantly the angle means it is not secure and aside from which the screws potetially expose the metal to rust (the area underneath the fuse - eg on the other side of the metal) being exposed to the environment.

As far as the sound being tight or having lots of reverb this depends on such things as sub box design (eg ported is louder but thrashier) and whether the car is lined with dynamat to make it a better sound box.
 
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yeah, the placement of the fuse was my main 'wtf'.
out of the many places to earth it, it was screwed onto...shit, i dont even know what he screwed it onto. ill check later

anyway..in regards to the actual placement of the sub, what would you recommend:
- facing the hatch door
or
- facing the backseats


on the amp itself, its got this knob reading 'Bass Boost' with 3 levels- 0, 6, 12
but the guy told me not to worry about it. does anyone know what it actually does??
its also got this 'gain' knob where it controls the bass...at least from what i hear.
rightt??

PS.
the reason im asking is because i dont have the manual, nor the box of the amp. i bought the very last one, so it was off the display wall. :eek:
 

seremify007

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My friend got his done at Lifestyle and his sub was in the same place as my cousin's (328)- in the boot, facing the inside of the car, against the back seat (and if you pull forward the back seat, you see it...

I think I might just go Lifestyle- they offered pretty much the same price range, or more if I choose to go with the Rockford/Punch.
 

loquasagacious

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The Fuse is not 'earthed' to the car, if you want to see the earth look for a short black 8gauge cable connecting to the amp.

The fuse holder is screwed onto your left strut-tower.

Facing in v facing out doesnt make a huge difference because of how the human ear works. It is generally assumed though that in keeps the sound in the car and out puts more of it outside... Personally I typically point them out because it's more visually appealing and harder for something to get caught between the sub and car.

As far as bass boost and gain go, if you go to the manufacturers webpage you will be able to get a manual which will explain it better than I can - eg my explannation is the higher you put them both the louder the sub will be.
 
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MTX manual said:
1. RCA Input Jacks – RCA type input jacks for use with source units that have RCA or Line Level Outputs.
A source unit with a minimum output level of 200mV is required for proper operation. However, this input will
accept levels up to 8Vrms.

3. Speaker Level Inputs – This input will allow the Thunder251D and 311D to operate from source units
with speaker-level outputs. Output speaker leads from the source unit should be tied directly to the wire harness
provided with the amplifier.
ok. so ive figured out that they didnt use the the RCA input/outputs because my HU doesnt have them, or theyre not suitable for them (not enough power?)

so instead, theyve used the speaker level inputs. what qualitative differences are there between these two installations?
and how are each of these methods powering my amp/sub theoretically? lolol.

thanks heaps for the input loq. youve been really helpful :)
 

loquasagacious

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In so far as I understand using RCA can yield a significantly higher quality because there is less distortion from the wires and RCA outputs are pre-amp eg they are direct from source and havn't been altered by the HU so are thus more 'pure'. I believe that RCA can carry more current/volts (watts even) than speaker level.

In sum RCA > speaker level.

They both do basically the same thing and carry an audio signal to the amp which then amplifies it (suprise suprise) and powers your sub/other speakers. Comparitive to the power the amp draws directly from the battery the power coming down the speaker wires/RCA cables is marginal.

Perhaps an explanation would be that the amp takes the input (be it RCA or speaker level) at say 10w of power and then takes another 100w of power and combines the two altering the wave of the additional power so it matches the input wave which in sum creates a 110w output that matches the input. As 110w is more than 10w the output is LOUDER.

In the case of an amp used in a sub installation it should have a low pass crossover which discards all high frequency input leaving the low frequencies which it amplifies and hence you get BASS.

/end over simplifictaion.

Hope that helped.
 

loquasagacious

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In so far as I understand using RCA can yield a significantly higher quality because there is less distortion from the wires and RCA outputs are pre-amp eg they are direct from source and havn't been altered by the HU so are thus more 'pure'. I believe that RCA can carry more current/volts (watts even) than speaker level.

In sum RCA > speaker level.

They both do basically the same thing and carry an audio signal to the amp which then amplifies it (suprise suprise) and powers your sub/other speakers. Comparitive to the power the amp draws directly from the battery the power coming down the speaker wires/RCA cables is marginal.

Perhaps an explanation would be that the amp takes the input (be it RCA or speaker level) at say 10w of power and then takes another 100w of power and combines the two altering the wave of the additional power so it matches the input wave which in sum creates a 110w output that matches the input. As 110w is more than 10w the output is LOUDER.

In the case of an amp used in a sub installation it should have a low pass crossover which discards all high frequency input leaving the low frequencies which it amplifies and hence you get BASS.

/end over simplifictaion.

Hope that helped.
 

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I'm under the impression if you don't have RCA outputs, you need the converter?... that's what Lifestyle, Stratty and JB told me.
 
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well i guess you dont
if you get a converter, youll lose a bit of frequency, or so i was told...

but id rather spend another 70 for the converter (and i wouldve if they had told me i didnt have an RCA output :() so i have better quality bass
 

loquasagacious

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Telling you that you need a converter is just a way to screw you out of abit extra....

Basically an amp that accepts speaker level inputs has a converter built in - you can get amps with this functionality from as little as ~$150.

So too re-iterate again if they told you that a converter was necessary there are several posibilities:
A) They don't know what they are talking about.
B) They are trying to screw you.
C) You had your heart set on an amp that didnt have speaker level inputs and they didnt have the integrity and/or knowledge to tell you what I just did.

A converter is ONLY necessary if you CHOOSE an amp that does not accept speaker level inputs.
 

seremify007

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Thanks for that info about amps- I didn't know... The Rockford and the Pioneer both only accepted RCA inputs- never really thought of asking are there any which don't need that.

Is mx audio a good brand?
 

seremify007

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Oops.. yep MTX- I think that's it; the guy at Stratty kept telling me that if I use that instead of Pioneer, I can get "much more powerful sound" for the same price. I keep thinking of MX as in that free newspaper they give out in the city ><
 

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