I'm a newb with car audio, and I'm a little stumped. I have an Alpine 9827 head unit connected to a 200W amp (don't ask the brand, it's embarassing) that is driving a single Infinity 1030W.

On my head unit, to get anything even remotely powerful coming out of my sub, I have to crank the SUB-W level to +15 (max). Is this normal? I've adjusted amp gain, other head unit controls, etc.

I knew the amp was relatively weak for the driver, but could it be that bad? I've got a new amp on the way that should do 600W bridged at 4 ohm, but I'm not sure that's the problem. I am correct to use RCA inputs over high-level inputs, right?

Or am I just expecting too much?

- Thomp

 

I remember reading somewhere that +15 is really the normal output strength and 0 is really -15 but I never verified it. I have the sub level on my 9815 set to +15.

 

Thanks for the info! That would explain what I'm seeing.

Kinda weird to have +15 be the untouched signal, though. The "+" should implicate adding something. Is that the norm for other Alpine units?

 

you are correct... and chances are you read that from me (if you saw it here.) +15 is the normal output strength (0 dB relative to the other HU outputs Front and Rear) and 0 is -15 dB (relative to the other HU outputs).

i did a good bit of research to find out this info, but the end result is if you pull up the technical specs on the Alpine HU in question, you'll probably find that info tucked away in there. (it is not listed in the manual.)

somewhere here, i have the whole discovery process documented.... if you'd like to see that -- i'll have to find it later, just ask here.

 

(and yes -- this is pretty typical for all the Alpine HU's. it isn't something i agree with (since it is misleading by nature), but it seems to be the general trend for the last few years.)

 

Thanks a ton for the info, guys!

The strangest part is that they don't list that in the manual.

 

Also, check you bass settings. If your bass is at 0, youll get squat. Put the bass to about 4-6 and the sub level to about 7. You should be good to go.

 

Hmmm, most helpful. I just installed William's sub a couple of days ago and was surprised at the complete lack volume of from the unit. I hadn't gotten around to playing with any the the HU settings yet. This info will hopefully help a ton.

 

Very interesting. I have always tried to keep the bass settings flat in the past, but I'll goose them up a bit. Are the setting for bass similar to the SUB setting where 0 is actually +n?

How about treble settings?

What is the proper procedure for setting levels when using "Alpine" logic?

I want to run out to the car and try it now, but I'm supposed to be writing code.

 

Dave and i don't always see eye to eye regarding tuning and wiring... still, i manage to accept and like him.



either or -- i'd personally set the 'bass' to 0 and set the sub level to +15.

the settings really look similar, but in action are not... the 'bass' setting is going to be increasing the bass response curve at a set point (80 or 120 hz if i recall correctly.), kinda like a 'bass boost,' but for ALL outputs of the HU (fronts, rears, sub). the bass setting is an eq type setting, where you're changing the response curve of the music across the affected spectrum and surrounding spectrums (like a hill on your response curve). the subwoofer level is going to be increasing JUST the subwoofer's pre-amp output level, which will directly only affect the subwoofer's volume. the subwoofer level is a pre-amp output level setting only.




and in fact -- because my HU is pretty inflexible for crossover settings and my amps do not have crossovers -- i have my bass set at -1 centered on 60 hz (to reduce the overall level sent to all speakers), but then have adjusted the subwoofer's level UP to compensate... thus offloading some of the low bass from my midbass drivers, and refocusing that load on the sub to compensate.
i'm really not happy w/ this setup, but until i can get a HU (something like the 9833/5) that allows me to cross over the sub at 60 hz or so, and allows me to cross the fronts at 50 hz or so -- it's the best i can do to balance and tune.


i hope all of this helps some...