Audio Help Please

[ste91]

I wasn't going to bother much with speakers but today I had a nice surprise and found that my car has some decent front and back speakers, and at some point had a sub/amp in the boot (wiring is still there).

The speakers in there are:

Front

Fli Comp 6

components - tweeters are in the doors where the mirror adjust is on Starlets

255 watts

85 RMS

90 dB sensitivity rating

50Hz - 20k kHz

Rear

components but tweeters aren't there

JBL GTO

270 watts

90 RMS

90 dB sensitivity rating

55Hz - 21k kHz

Now I have a few questions, those speakers are good enough for me, but I've got an amp that I was given a while ago, it's small/light so I like it, although it's only 80+80 watts, I'm thinking of using it to power the rear speakers. Would it be worth using or shall I just leave them running off the CD player?

One thing though I think the crossovers that come with the speakers are in there somewhere under the dash but if there's a possibility that the person who put the speakers in didn't use them, should I get an active crossover?

And lastly, is it worth getting a sub? I'd rather not if I can get away with using what I've got as the more money I spend on audio = less to spend on things that are more important to me. But I want good quality sound. Do I "need" one to get the best out of it?

Or - another option I've though of - I was also given a subwoofer crossover and soon I'll have another amp, and I have some unused speakers in my room (old style wooden box ones) with decent 10 inch/250w speakers, maybe I could take one of them out, make an enclosure for it and run it off the amp+crossover? Or would it just be shit?

[chriswoodfto]

buy yourself a small decent amp, the vpower alpine ones pop up on ebay for next to nothing, think the small ones are around 200w rms, run the speakers to the amp and use the cross over on the amp. ive just taken my sub out because of my little girls pram. :'( its horrible, even if you get a small sub and not too bass'y it improves music so much more by having a bass line. im putting it back in tomoro and finding a smaller pram.lol. ive got two brand spanking 10" jbl subs in my hall way. bought them last year for my old car but came accross a kicker L7 really cheap a week after (the best sub money can buy) if you want one you can have one for 20quid plus postage, nice cheap xmas to your self.

[Blair]

^^^as above mate...^^^

but my personal preference is only to use the amps built in crossover when running the sub(s) from it, and then again i would use the subwoofer pre-out to feed into this amp.

is the amp you have 80 watts RMS each side, or just 80 watts MAX each side??

if 80 RMS each side, it would be fine to run the rears or even the fronts instead, your own preference - but as a rule of thumb, I always get an amplifier that can power (RMS) slightly more than what my speakers (RMS) can handle, so that i am not running the amplifier to its limits at all times if i want to crank it, or have it loud for prolonged periods say.

ALSO - Subs FTW - i've never put mine in ma V, because of power/weight, but defo miss it!!

[chriswoodfto]

yup, you cant beat a sub, im not into 'fill the boot' stuff, just buy really good quality things that make a nice noise, i only ever use alpine audio gear (or pheonix gold) and the kicker l7 i highly recomend.

[Blair]

phoenix gold mate alpine

i'm quite into vibe just now too - should give them a wee checking out - some of its a bitty pricey tho

[ste91]

I think I'm just going to try it with the amp to the rear speakers, leave the sub for now, see what it's like if I decide I want a sub I'll get one as there's plenty of boot space in the CRX anyway.

@ Blair I'm not sure, but on the other side of what you say I thought it was always good to have the speaker's max atleast as good as the amp that's powering them so they don't blow?

Also will I get more of a "bassy" sound if I make up some enclosures for the rears? The JDM CRX actually comes with "bass tubes" in the back which are just plastic moulded enclosures to fit in the space, could probably make some though.

[chriswoodfto]

you coudl always sell the speakers in the rear if there good and buy some speakers that are more intune with low notes for the rear and some 3way with tweeters up the front. that way you wouldnt have to bother too much with the sub and youd still cover all the right notes.

blair-i know pheonix gold are awsum, soooo pricy tho. got a couple of bits of theres to go on ebay.

[Blair]

you're there mate, although theres many factors i take into consideration - i.e. components in the amp tending to give up the ghost if ran to there extreme etc etc

RMS power is commonly (and wrongly) known as the average power output... but in l amens terms you could say its the continous output, so indefinitely you do want to try and match the RMS power handling of the speakers with the RMS output of the amplifier as close as can be (also taking into consideration things like impedance etc etc), but like I said i would always tend to go for an amplifier capable of a little more than my speakers RMS handling (NOT the speakers MAX handling!! lol)

And again another reason i would get an amplifier with a slightly higher output, is that when you start to run high power from the amplifier, i.e. to its full capacity, you end up getting more distortion introduced into the sound - if you look at an amplifiers THD (threshold distortion), it will usually quote for example ' THD: 10%' , so here basically for every 100 Watts RMS output, 10 Watts of that is pure distortion!!

And any good sound engineer will know when there speakers are being ran too highly - you will either get distortion fed from the amplifier or distortion because of the power handling of the speaker - and all you need to do,is...

TURN THE GAIN DOWN

hope this helps

[ste91]

Cheers mate, I only plan to run it at about half anyway, I'm not after excessively loud volume or anything like that, aslong as the sound is nice and clear. I'm not big into car audio really, I didn't even have a CD player in my old Starlet, but I was forever getting asked to "put some music on" and then had to tell people that I don't have a CD player lol.

But I thought seeing as it's got some half decent speakers in there now I might aswell make use of them.

[Blair]

no probs mate, sorry if i rattled on.lolage.

quite right mate - make the best use of what you can - and forgot to say if you stick the sub in a box - there'll be more bass (more compression in a given space etc)

'choonz' are good for those long drives to get the car mapped!!