[AgentSingh]

Hi sorry if this is has already been answered but I need advice on what speakers to buy for my car:

E46 320 D SE with Business Head Unit & Denson 100 iPod Kit

Basically problem I have is my speaker on the rear shelf is dying a slow death, it sounds as if its blow however only sometimes, I removed it changed sides still the same problem.

Either way I’m not sure which speakers to buy but I have seen the following 3

http://www.caraudiocentre.co.uk/product_m-in-phase-xtc52_p-19734.htm

http://www.caraudiocentre.co.uk/product_m-pioneer-ts-a1303i_p-23140.htm

http://www.caraudiocentre.co.uk/product_m-mtx-thx502_p-24215.htm

My budget is about £60 GBP which is why I have looked at the 3 above, just wondering will these work with existing wiring or will I need to rewire them with better cable? Also power wise will I need an amp or will they be ok from the factory head unit?

Also regarding the front door speakers does anyone know the depth of the factory fitted ones so I can find something similar? (The door speakers will be replaced next month as need to budget for the lads holiday impin: )

 

[ca1242]

If you have an oem amplifier, you might need to look at replacing amplifier + speakers or new head unit + speakers.

 

[Orion329]

the impedence on all the speakers you have picked out is 4-ohm. from what i've read, the speakers in the rear deck are 2-ohm speakers. if you get 4-ohm speakers, you'll be getting weaker sound from them and it could be damaging to your amplifier since it doesn't expect to face as high a resistance (someone please confirm that last point).

a lot of people would argue that the rear fill is not even necessary, so dropping a lot of money on those speakers isn't worth it.

if you're budget is only £60 GBP, i'm guessing you're not going to be able to rip out the old amplifier in the trunk to replace it (or just the head unit). but if you could, i'd go with what ca1242 recommended.

 

[ca1242]

Actually, works the other way around. Higher impedance = less current = less power. You are correct about speakers not being as loud. Other issue is crossover. OEM amp feeds a filtered signal to each respective speaker, so if you connect a coaxial speaker to, say the midrange speaker wiring, you will get no highs or mids out of it.

 

[Orion329]

thanks! so you're saying it will hurt the speakers if they're putting up higher resistance than what the amp is designed for?

as far as my knowledge of circuits goes, it seems that if the power is for the most part a constant, then i can apply what you said above, indicating that as impedance (resistance) rises, the current will diminish (though not linearly). since i don't hear many people talking about the current that's passing through their speakers, is it the watts rms that is changing and damaging the speakers? or is it all much more dynamic than that.....

 

[blk04zhpcpe]

you are exactly right in that as the load impedance rises, the current thru the load will drop but consequently so does the power. the greatest concern is that a lower maximum available power increases the chance that you will exceed the amplifier's ability to provide a clean signal. an overdriven amplifier will burn a voicecoil very quickly. the one thing i would point out is that efficiency(how loudly a speaker will play relative to its' 1 watt input) has not been mentioned here and if the replacement speaker chosen is a very efficient one, it might play pretty loudly on what power the hk amp has to offer. can't objectively compare because i have not seen anyone state the efficiency of the stock speakers but consider that a higher number there would be beneficial.

 

[Orion329]

thanks for your input blk04zhpcpe.

i wonder where AgentSingh ran off to....

 

[ca1242]

There is no risk of burning the amp or speakers by adding a higher resistance speaker. You will just have mismatched sound.

 

[AgentSingh]

Thanks for the advice, however the car has just died lol! Well the gearbox went so i have decided its time to fix sell and buy the E90!

 

[Many330i]

There is no risk of burning the amp or speakers by adding a higher resistance speaker. You will just have mismatched sound.

What about adding 2-ohm speakers on a 3-ohm HK amp? Do I increase the chances of clipping/burning the amp. I suspect a higher current/power will flow to the 2-ohm speakers but that doesn't mean the amp is making more power, right? And if so, there shouldn't be any risk for damage to the amp, correct? :hi:

 

[ca1242]

Amp will make more power. Not sure if it is capable of handling the load. As I said before, buying random speakers and hooking them to the oem amp is not the best solution.

 

[uninc4709]

Amp will make more power. Not sure if it is capable of handling the load. As I said before, buying random speakers and hooking them to the oem amp is not the best solution.

listen to that statement. oem or bsw

 

[ca1242]

...or aftermarket amp

 

[Many330i]

Amp will make more power. Not sure if it is capable of handling the load. As I said before, buying random speakers and hooking them to the oem amp is not the best solution.

CA, can you clarify what you mean by 'random speakers'. I was of the opinion that if I find speakers -3ohms nominal and power rating close to 21-35W rms, generally speaking the OEM amp should be safe. Now, speakers with those dimensions are hard to come-by but I found some 2-ohms that are close to....

 

[ca1242]

There is much more to speakers than ohm ratings. Speakers have different sensitivities, frequency responses and limits on their frequency responses. By adding any random speaker (even if you match impedance), you might get lucky and get balanced sound, or it could sound like crap.

 

[Many330i]

There is much more to speakers than ohm ratings. Speakers have different sensitivities, frequency responses and limits on their frequency responses. By adding any random speaker (even if you match impedance), you might get lucky and get balanced sound, or it could sound like crap.

Okay, given all that you know about audio, about the BMW system and amp especially and about speakers in general, what parameters (or ranges) should I be looking at to narrow the possibility of getting unbalanced sound..? :hi:

I refuse to spend money on the BSW kit or a new amp, partly because the high-end don't excite me that much and I have a sub to gnash the low-end properly. So, all I need are 4 coaxial speakers (at most) to replace my 6.25's..:ben: I might do compo's if I find some that dig deep and the price is acceptable.

Please don't say you don't know, I'm sure you can at least offer some parameters (i.e ranges of dB's, Fs, W etc) to complement the OEM amp given your e46 install experiences. :bow:

 

[ca1242]

You have two choices: BSW kit or oem replacement speakers. Anything else is a gamble.
I don't know oem speaker parameters (and you will not find them anywhere).
As I said before, if you want to do things right, spend a little extra money and get an amp + speakers (or head unit + speakers).

 

[Many330i]

You have two choices: BSW kit or oem replacement speakers. Anything else is a gamble.
I don't know oem speaker parameters (and you will not find them anywhere).
As I said before, if you want to do things right, spend a little extra money and get an amp + speakers (or head unit + speakers).

Thanx for your help! :banghead:

 

[pastE36prsntE46]

CA is right, as BMW was a genius to put all these speakers into our cars, they all have different functions and control different freqs. In your case of not wanting to spend the money, I would buy replacement HKs and then watch the volume knob.

 

[Micah D. Cranman]

Another alternative is an open-box Stage 1 (if we have one) or someone selling the kit because they decided they wanted to upgrade, killed their car, etc. You have some other options if budget is the issue, but buying drivers off the shelf and hoping they'll sound good, even if you somehow got the specs and they matched, is a bad idea. Little known fact is that there is a strong tendency in the car audio world for people to just make up specifications, so what works on paper doesn't work in the real world most of the time.

Good luck!