16 replies to this topic

[Imprezed]

Hi all,

Okay so i have a complete base model 2015 impreza i bought new in 2015. It has a standard infotainment unit, which works great for what i use. Problem is, the sound in my car is rubbish if im being honest. Im not after a so called "fully sick" system, but just soimd sound with nice base. Im electronically clueless and was just wondering what would be a good place to start?

Im thinking some good speakers for the front doors. Do i need an amp to get full power to the aftermarket speakers i may buy? Ive been told i cant upgrade anything unless i change the head unit by a JB HI FI salesman (i know) problem is i dont know anything..

My only other option other than here is call an auto electrician and ask for advice, call subaru and get a quote for a premium sound upgrade, or this forum realy..

Ive had geat advice from guys on here previously which ive followed and very happy.

Sorry if this is posted elsewhere.

ANY FEEDBACK appreciated.

[duncanm]

You can do as little or as much as you want - don't trust the JB guy.

 

If you just want sound improvements, the #1 step is speakers - get better ones.  Get something to match what's in there now - replace splits (woofer and seperate tweeter) with splits, for example. You do not need to upgrade the headunit or anything else.

 

I'm not across brands here, do your research on some car audio forums, but I had excellent results with the bottom-end of Morel's range (Morel maximo).

 

While you're rummaging around with the door cards off, slap in sound deadening material in the doors (the heavy stick-on type) on all large metal spaces. This makes a big difference and is relatively cheap. Use the car-audio specific stuff, or just the stick-on aluminium roof flashing from bunnings

 

From there, you can look at amps, headunits etc, but really, speakers are #1 by a mile.

 

Unless you're a doof-doof boy, standard in-door speakers with the std. headunit give you plenty of (clear, balanced) bass.

 

 

ps: don't get caught in the bullshit about power ratings of speakers vs. headunits.

There are simple guidelines you need to follow here:

- more power is louder (obviously), but the standard 35W in a decent headunit is plenty loud.  You'll rarely listen at over 5-10W

- speaker ratings are fairly meaningless. Just don't turn an amp up until it distorts.

[Imprezed]

Thanks for reply mate.

I got these 6 plug and play speakers from kicker made for my subaru if ebay relatively cheap. I will attempt to instalp myself.

4 door speakers: H631SFJ001

2 dash tweeters: H631SFJ101

Now only real question is if i can get the max power out of these speakers without an amp? I dont think i can which is a big waste, but will still be a big improvement as you say. I realy cant get my head around a amp and HU combo that can 100% power all 6 speakers to there full potential.. not 70%.. also looking at a sub. So confusing. My math is showing me i need atleast 2 to 3 amps to power all 6 speakers and a sub to 100%??

Im sure ill get pointed in the right direction.

Cheers for the points..

Sam

[duncanm]

Now only real question is if i can get the max power out of these speakers without an amp? I dont think i can which is a big waste, but will still be a big improvement as you say. I realy cant get my head around a amp and HU combo that can 100% power all 6 speakers to there full potential.. not 70%.. also looking at a sub. So confusing. My math is showing me i need atleast 2 to 3 amps to power all 6 speakers and a sub to 100%??
 

 

typical head unit might be 2 x 25W or 4 x 25W.  25W is a limit per channel based on the available voltage (12V) into a 4ohm load (the speaker). peak power is V^2/R. RMS power is 1/sqrt(2) of that, so RMS power = (12^2 / (4 * sqrt(2)) = 25W (ish).

 

Getting more than that involves more sophisticated electronics - which is why that's a price breakpoint at 25W

 

Each 25W channel run at max power will need about 2A.

 

So a four channel headunit running flat out will consume about 8A.  It'll sound shit, as it won't be designed to run at that sort of volume.

 

As I said - don't get caught up in the power ratings (of speakers in particular).  10W out of each speaker is plenty loud for most circumstances.

 

(EDIT: typo in my first post - should be 25, not 35. Most manufacturers fudge their numbers up to about 50W by assuming higher input voltages, like 16V).

[Imprezed]

Okay so i need to change my HU or get an amp to successfully run all 6 speakers?..

[Imprezed]

I have the bottom of the barrel base model HU. would you change that or keep it and buy an amp? Im told an amp will be useless with this HU..

[duncanm]

Does your model already have dash/A-pillar tweeters and rear door speakers?

 

If so - I'd start by just doing a straight swap for your new speakers and see how you find the sound, then worry about amps and newer HU's if you're not happy.

 

The OEM HU will be 4-channel.  Tweeters just run in parallel with front doors (though the model you chose are coaxial with tweeter, so you're sort of doubling up on the front tweeter which won't be optimal. Suggest you maybe disconnect the coaxial tweeter if you install the dash tweeters)

 

Maybe these might help:

 

http://subaruonlinep.../H631SFJ000.pdf

 

[Imprezed]

The OEM HU will be 4-channel. Tweeters just run in parallel with front doors (though the model you chose are coaxial with tweeter, so you're sort of doubling up on the front tweeter which won't be optimal. Suggest you maybe disconnect the coaxial tweeter if you install the dash tweeters) i dont quite understand this hey.. but that vids great, funny enough i was just watching it before you replied.

[duncanm]

On each channel, you typically run 'splits' (woofer and separate tweeter), OR run what's call 'coaxials' - they're named that because the tweeter and woofer are in line (coaxial) mounted in one unit.

 

Wiring wise, for coax, its just plug in one unit for each channel.  There's a (very simple) crossover filter to cope with sending the high frequencies to the tweeter and the lows to the woofer contained in the speaker unit.

 

For splits, you might have an external crossover filter mounted in the door, which has one input (from the HU/amp), then two outputs for the tweeter and woofer.  Does the same job.  Cheaper units (like the OEM) just have a capacitor in the tweeter to do a fairly cheap/shitty job of filtering.

 

So - back to the point.  If you put a tweeter in parallel with a coax, you have two tweeters.  What'll probably happen is that you 'load up' the highs with approx 2ohm (two 4ohm speakers in parallel), and the lows (woofer) with 4ohm.  This is a very simplistic way of looking at it.

 

HU/amp will most likely be fine, but the balance between highs and lows will be out of whack (too much treble), plus you'll lose the imaging of the soundstage, as the highs (from which your brain determines the directional information) will be coming from two sources.

[Imprezed]

Ok great info, and explained well for a mere clueless person like me.. anyway reference to the vid. Doesnt the bloke run tweeters in the dash and four coaxials in the doors? Which is what i went with..

So you think this is wrong?

[duncanm]

Ok great info, and explained well for a mere clueless person like me.. anyway reference to the vid. Doesnt the bloke run tweeters in the dash and four coaxials in the doors? Which is what i went with..

So you think this is wrong?

I didn't watch the vid, but yes. Sounds wrong.

 

I wouldn't stress about it.  Try it.. if it sounds wrong, then look at clipping a wire to the tweeters in the doors.

 

You're not looking for top-notch big bucks audio

[Imprezed]

Ok thanks for the pointers mate. I will post results once done. But yeah this is a pretty big deal for me. I cant afford a STI with premium sound..

[Imprezed]

Also this is the complete subaru kicker upgrade minus sub. (The speakers look coaxial, but im assuming there not)..

Does anyone know if there splits or coaxial? I cant find it anywere..

[duncanm]

Looking closer at that screenshot from the vid above, it looks like 1 set of coax (for the back) and one set of splits (for the front).. just what you want (if that's whats in the box).

[Imprezed]

Ok thanks. Lets hope so. Really annoying subaru or kicker dont allow there specs to be available for this set..

[Imprezed]

Looking closer at that screenshot from the vid above, it looks like 1 set of coax (for the back) and one set of splits (for the front).. just what you want (if that's whats in the box).

[Imprezed]

Hey mate the speaker on the right is the stock OEM factory door speaker. You deff get with the complete set, Four on the left.. also you get two dash tweeters, aswell as a powered sub if you like. But yeah, i understand now what you mean about highs.. wouldnt subaru/kicker put splits for the doors if the highs are too loud? Itd make sense anyway..