14 replies to this topic

[Gr33kGod]

Hi everybody,

I got a Coustic 480QE and it seems pretty good, the only gripe i have is that it isnt as clear as i would have thought, unless its the splits.. but a guy from doran said it would probably be clearer with a better amp.

I just wanted to know, if i decided to replace it with a similarly powered amp (ie a MTX or Rockford Fosgate 501x) would I:

1) See any difference in the sound quality? ( Im running JL 6" VR Splits)

2) Will the cable be okai for the new amp? (say if i get a slightly more powerful amp 70X4 for eg, is that going to be an issue?)

Also what would people recommend as a sweet replacement?

The setup is as follows:
Pioneer 5650mp deck
JL 6" VR splits
Clarion 5.25 coaxials fill (deck powered)
12" Crossfire CF212D (duel voice coil)
Coustic 480QE running in bridge for sub.

Thanks
Andrew

[ix]

clearer?
Thats assuming your using the crossovers on the amp. Does the coustic amp produce the power you want/need to run your current equipment?

you haven't mentioned what guage cable your running...

i think you might have more success building a new box for the sub.
What are the dimensions of the box?

[Gr33kGod]

yeah im using crossovers on the amp. i have some pictures of the settings. I think i'm happy with the power it produces, the sub is more often than not rather 'overpowering' i just turn down the bass boost in such a case.

I'm not sure what guage cable i'm running , how can i find out?

The sub box was built at doran pro audio specifically for my car, the dimensions are : 55cm accross, 34cm High, 32cm Deep.

[ix]

I suggest you keep bass boost off all the time if you have enough power...keep the gains down and lower the xover freq may help you oversome too much subwoofer output

what is the recommended volume of a sealed enclosure (im guessing its sealed) for your sub?

hrmm what guage...there was a CAA tutorial a while ago that had pictures of different guages of wire.

I use my fingers to judge, but my fingers would be different size to yours probably

8 guage Pinky...0 guage thumb j/k

[Gr33kGod]

oh ok cool i'll see what i can dig up on the cable.

the settings on the amp are as follows ( can you see anything that might make things a bit clearer)?

HPF on splits > ~190-200, Boost> 0
LPF for sub > ~80 id say, > Boost Full +18
Sensitivity is set to max by the look of things

On the head unit then, does it matter what the HPF is set to?

[ix]

yeah it does matter

its a bit of a worry that your HPF on the front stage is set so high. Your 6" splits should be able to play much lower. At least 80 to 100hz
I think the HPF set so high is why your thinking things don't sound so clear. The initial impact of bass is played by your front stage 6" speakers (midbass) usually. With the HPF fairly high, your front speakers aren't doing much midbass work, so your hearing your sub most of the time. With a lower HPF for your fronts, I think it should sound much better.

Turn off that +18dB boost on your amp...

turn down sensitivity/gains on the amps for all channels.

JohnA or Shiny did a lovely tutorial on setting gains a while ago on the CAA Tutorials

[Gr33kGod]

I turned down all the gains n stuff it certainly sounds more blended in now! Thanks for that, its actually pretty clear now i doubt a different amp will make any sort of noticable difference.

Just a note, the sensitivity nobs on the amp for front and rear are like on/off thingos, if i turn them all the way to the left the splits or sub dont work at all, so i kept both sensitivity nobs to the furthest right, but turned down the 'boost' knobs all the way to Zero!
Much better though definitly!

HPF is set to 70ish, LPF is set to 80ish and HPF on deck is set to 50... (its either beteween 50,80,120)

[ix]

i don't think you need the HPF on, on the deck at all...
but good to hear its much better now

[Maz]

That coustic amp kicks bum. Thats what im using. I have it bridged to 2x 240wrms for my fronts and OMG it sounds good

Keep adjusting the gains and ull find it will sound much better. Come to a CAA meet and im sure someone can help you.

[Gr33kGod]

48.14 L is the recommended volume for the sub for sealed box (it is sealed)

[ix]

well that box u have is approx 43L so shouldn't be too bad...

[Mickee]

Gr33kGod said:

so i kept both sensitivity nobs to the furthest right,  

I think you should turn both sensitivity knobs down just a little bit. I usually find its not the best having your gains cranked up to their maximum, it puts your amp at risk of clipping unnecessarily...

[claf_43]

are you expecting too much from your splits???

[Gr33kGod]

ohh nah the splits are pretty good now im quite happy wif the set up, if i want more bass its easy to turn it up from the head unit.

[shiny_car]

btw, between your amp and the splits, the splits are going to be the weakest link. or at least you'll gain a much more significant improvement if you upgraded these rather than the amp. in general, you'll gain only small benefits when upgrading an amp, but can gain lots with better splits.

also re-evaluate the quality of their installation, taking into considering sound deadening, solidity of mounting the woofer into the door, and sealing of major door air leaks including the large service holes.

yes, i recently wrote a Tech Article on properly tuning gains. have a read if you haven't already to see if helps.