Alpine 9835 System Setup - Help?

coajt

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Hi Guys

Long story....here we go....

I have an Audi A3 with an Alpine 9835 (US spec) head unit along with a 4 ch Alpine amp (MRV-F405) powering a pair of KAPPA 50.5cs components in the front and a small JL sub in the boot.

The physical x-over settings on the KAPPA speakers are set to the FLAT option on them. Unfortunately I do not know what settings are chosen on the amp as this is hidden in the body of the car and I cannot get to it without ripping out half the interior however I am willing to do this if it will help to reach audio perfection!

The problem is since the system was installed I have never been at all impressed and as its cost over £1200 quid I feel the sound produced is poor compared to the BOSE setup I had previously.

The main issue is firstly I dont understand what X-over settings I need to set on the HU to produce clarity in the vocals as at the moment all sound appear to be very tinny, maybe too much treble? Also as I'm a real beginner I dont fully understand by adjusting something, what changes this makes to the sound...

If someone has a similar setup or can provide a few pointers to gain high quality audio I'd be very grateful. I generally listen to a mixture of pop and rock.

Please note I do not have any rear speakers...would it make a difference if I installed a half decent pair of rears?

The amp specs are....60w x 4 (4 ohm), 180w x 2 bridged (4 ohm), all RMS @ 14v
The kappa specs are...13cm comps, power handling, RMS - 85 watts, power handling peak - 255 watts.

I know the 9835 head unit is a nightmare to use as it has hundreds of options however I've mastered changing the settings just dont which settings I need to set, what is slope, DB, HZ, etc...

Thanks

Adam
 
first off you dont need rear speakers, they will drag the sound back which will make things worse

as a general rule i always say to cross the sub at 80hz low pass and the fronts at 80hz highpass, however it may be trial and error with the JL 6.5" (IIRC thats what it is?) as i believe its more of a mid bass driver than a sub unit

what other options are on the kappa passive crossovers?

who set up the amp for you, are the rear channels bridged into the sub and the front channels running to a set of components each?
 
Cheers Dean

What slope do you recommend to use? I don't really understand all this slope and decibel stuff.

The sub is an AndyMac Stealth special and he also setup the amp for me.

Thanks

Adam
 
The amp was setup with 2 channels bridged for the sub with Xover set at 85Hz, and the other 2 channels driving the front comps, with no Xover setting as this can be controlled by the HU.
The HU is overly complicated and just playing around with it for 15mins I couldn't get any decent bass from it (it doesn't have Bass or Treble controls).
I've fitted about 15 of my subs and haven't had this problem with any of them. My wifes A3T has all Alpine with the stealth sub and it sounds great, but it's an older model with proper controls.
Seems ludicrous that you have to go into multiple menus just to knock the Bass up a notch.
 
My Kenwood KDC-PSW9527 also uses a more complex approach where you have to set it up to really make use of the HU. I normally try to get a couple of Hz overlapping between the sub and the comps since that cross over point frequency is where each speaker is going to experience a drop off in quality and power. I would also just re-check that the wiring is ok. There could be a fault somewhere?
Coajt, ask AndyMac to have another look, I am sure he can get it right for you.
 
Adam, if you want I can swap out the HU for a normal Alpine and prove that the amp, comps & sub are fine, it's only a 10minute job.
One thought is that apart from the complexity of the HU, it was a very tight squeeze getting those Infinity's in the front doors, maybe the spacer rings are fouling the cone and restricting the movement.
 
the slope and decibel rating is the 'fall off' that will happen when the crossovers are in action

e.g. you high pass the components at 80hz 12db/octave, anything below 80hz will be gradually filtered resulting in reduced noise level so the volume doesnt stress the speaker

setting up a sub its never wise to boost the bass on it anyway, it will just force the amp into clipping if you want to increase the bass from the mid unit then fade out the fronts

do not boost the bass, if you need to do this get a more powerful amp

Adam where are you based in the midlands? PM me if you dont want to say on the open forum, if you're close to me i could take a look if you like? /ubbthreads/images/graemlins/smile.gif
 
Hi Andy

I'm not doubting your install in anyway. You did a quality job and have offered me continuous help since. Its just frustrating that with all the kit I've got in the car the sound produced isn't that impressive. I think your right though, the root cause of it is probably the complexity of the HU, maybe its simply time to ditch the Alpine?
 
Hi Dean

ok great, thanks so I've set the comps at 80hz/12db, what would you recommend for the sub? 80hz/18db?

I live in Tamworth.
 
Dean, I think we've discussed this before and the stealth sub doesn't conform to the normal car audio rules. What I was referring to was the fact that with all the installs I've done, with exactly the same amp & sub, the bass from this HU was weak, even with the sub control on 15. Given the thing has 4v pre-outs I get far better results from Concert/Symphony HU's which seems wierd.
I do remember having a similar problem with "Darkspins" setup (don't think he's on here anymore), and he had a 9812rr, which is even more complicated than the 9835, but we got round it in the end. The first setting on the sound menu was "defeat on" and we'd managed to select this mode which by passes the pre-amp and just sends raw audio to the amp. Nice one Alpine! Great feature but why have it as the first option on the menu?
Given the vast difference in bass levels on CD's these days, you do need to knock the bass up & down depending on what you're listening to, regardless of the power of your amp.
 
true i dont want to go there again /ubbthreads/images/graemlins/smile.gif but.... some of the guys may be thinking that cranking bass on the HU is all well and good to do and its not really a good move - just trying to extend the life of your subs Andy! /ubbthreads/images/graemlins/laugh.gif

you DO NOT want to be boosting bass on the head unit, if you are doing this you need a more powerful amp, if you want some sort of control on the bass then get an in line level control like the one below;

http://www.caraudiodirect.co.uk/product_...0a040025ec77037

of the two amps i scoped this weekend, one guy had bass boosted and was clipping very badly

guess what, knocked off the bass boost, scoped again (re-adjusted the gain to compensate) and the output voltage of the amp was higher

i agree about the Alpine HUs though, although its the 'bling' generation where stupid options and flashy lights make people buy stuff /ubbthreads/images/graemlins/smile.gif

like i say, dont want to get into an arguement and the above is just my 2p, people can take it or leave it /ubbthreads/images/graemlins/smile.gif

Adam, i dont suppose you'll be at Trax (silverstone) this weekend? if not let me know what nights you are free and if you want me to i'll take a look
 
He's got a non-fading sub out on the HU with Sub level control so controlling the sub is not a problem, it's just the level from the HU is not as high as every other HU I've experienced. Very strange on such a sophisticated piece of kit.
As I say the older style Alpines work a treat and normally run with -2 or -4 on the bass setting.