Hey folks. Just got a sub added to my Bose today and while I'll admit it sounds good, I'm a little less than blown away. Here's the setup:

4th Gen Bose
2 10" JL W0 in sealed powerwedge enclosure
Rockford 500w RMS amp w/ remote punch bass control(501S)
1 farad phoenix gold cap

Here's my problem: I bought a JL sub b/c I loved how tight it sounded in my other friends cars, exactly what I wanted. The way it's set up now, the bass seems to be way too loose and boomy. On dance tracks with a fast beat (Tamia - Stranger In My House) the sub seems to always be half a beat behind. Ski port open or closed, makes no difference. Rap music is fine, but that's not surprising. How do I make the bass tighter? Right now the box is not bolted to anything. Will that make a difference? Is there a way for me to bolt it down but still take it out if I need to?

Also, even though there's no distortion, the levels seem to be way too high. The gain and the crossovers were set by the shop, and I'm assuming they did it correctly. I ended up lowering the crossover from 100 to about 75. Right now I need to turn the remote punch control for the sub all the way down and the bass **** on the bose down about 1/3 of the way from flat for it to not sound too bass-heavy. The bass **** on the bose makes a huge difference as to how much bass the system puts out, while the remote punch **** doesn't seem to do as much. So, I end up leaving the remote punch **** flat and adjusting the bass with the head unit anyway. Is this b/c Bose is EQ'ing the crap out of the signal even when it's supposed to be "flat?" How do you guys with bose + sub have your bose settings? Ideally, I want to be able to leave the head unit flat and use the remote punch to adjust the sub if I want a little boost. Isn't that the way it's supposed to be? Should I try lowering the gain so that the "flat" levels on the bose actually sounds flat?

I just spent a grand on all this stuff today and I'm not as happy as I should be. Any input you guys can offer would be greatly appreciated.


Larry

 

I guess you have the signal from the HU going to the Rockford AMP? That would do it. The Bose HU sends out a a strange Non RCA type signal. It has loudness in it. Since it has loudness, the louder you play it, the less the loudness effect is. I suggest you try tuning the subs while your system is playing loud, and leave the tone controls flat, bass and treble both at 12 o'clock. That will reduce the loudness effect and make for a better bass balance.

I would also suggest you put a capacitor on the rear Bose speakers to reduce the bass they put out, so they will distort later, too, and let the subs do more of the bass work.

DW

 

Actually, I think the signal is tapped off the rear speakers after the amp, but I'm not sure which adapter they used. I never end up turning the bose bass **** past flat, so I'm not too worried about the inside speakers distorting.

By tuning the system, do you mean adjusting the gain? The crossover seems optimal around 80 and the gains are adjusted by the shop to be maxed out when the bose system is maxed out. I tried my friend's bass cd, and it only sounded right when the bose **** was at max below zero.

The bass is still way too loose for my tastes. I like that tight punchy bass and will take SQ over SPL anyday. Is that a function of the box size or interior size or both? If it's the box, I might swap for a single sealed 10 and see what happens.

 

Interesting. My Bose rears distort from bass at high volumes, and the bass **** is flat. The rears are usually what's holding the sytem back from playing louder. I guess it depends on the type of music playing.

By tuning I mean gain and frequency. If the shop got that part right, then leave it alone. But your observation of boominess would suggest otherwise.

If the amp is tapping the singal after the bose rear amp, then it is getting the EQued signal OF the Bose amp. I have a strong feeling that the boominess may come from there. My observations of the BOSE system are that the rears are EQued to emphasize the boomy, high bass, taking advantage of the trunk, and the Bose fronts produces the deeper bass, and the tighter upper bass. You may want to switch the tap to the front speaker after the amp.

Ideally, the perfect solution would be to get an adapter to un-BOSEify the audio signal to make it a standard RCA line-out, because that is what your amp is expecting. That signal would then feed your amp.

DW

 

This is what you need;

http://www.linkmeup.com/pd2.htm

It's a little priceir than most other adapters out there, but it's the only one (that I'm aware of, and I've looked hard!) that generates a clean, much-less-distorion signal by NOT using the amplified signal after the amp. It also un-BOSEifies the signal, too, so your amp gets the correct signal.

DW

 

Thanks for the input. So this unit gives you a true flat signal that you can send to the subs from the Bose head unit? I wish I knew that before. Rather than spend another $100, I might end up living with it for now and putting that towards a new head unit.

 

Yup. Standard Line-out RCA. Any aftermarket unit will be happy with that signal
I have the PD-4. With that one, I was able to have my aftermarket HU, A Clarion DXZ 815 MP3 CD unit, drive the existing Bose AMPS/Speakers. I kept the Bose sound, in fact it got better, b/c the Clarion has a way better CD unit than stock. It costs $180 with the harnes. Most others on the org would rather spend more and replace the entire Bose system. I beleive you can put in a system that sounds better than Bose, but it's alot of work, alot of time and quite a bit of money. The Bose advantage is that the system was fine tuned for the Maxima cabin's acoustics, and that's the fine tuning that takes alot of work when trying to match your Polks or Kenwoods etc to the car.

DW

 

Do these Audiolink adapters do the same thing as the PAC OEM-1 and OEM-2? I think I'll end up adding a head unit eventually anyway for MP3, so am I better off getting the PD-4 right off the bat? I wish I knew about this before I brought my car in for the install last week.

Should I order this online or pick it up at a shop somewhere? I live in the NYC metro area. Thanks again.

Larry

 

It looks like the PAC OEM-1 and OEM-2 use the speaker outputs to create a line out for you to use. That's the most common type of audio adapter out there. The advantage is that they are cheap and common. The drawback is that you're taking an AMPed signal and then AMPing it again. There's distortion added to the audio signal because of this. Your system will not be able to play as loud and cleanly. The PD-2 and PD-4 take the low level signal before it has been AMPed and convert them to line -level RCA. Those PAC guys have something, or will have something, similar to the PD-2s and 4s, the C2A-GM24. It seems to be tailored to GM vehicles, though.

Another good thing about the PD-4 is that if I want to add a sub, no problem. Take the standard sub-output of the Clarion HU (having already used a line-out to go to the PD-4) and plug it directly to the sub's amplifier.

If you really want to maximise the BOSE potential while mixing in aftermarket stuff, those PDs are the way to go.

Lastly, when I upgraded my HU, it was then I realized the the stock Bose HU actually had automatic loudness built in. It is never mentioned in any of the marketing brochures etc. Once I knew that, I was able to tune the system properly, by basically tuning it when playing the music very loud, the point where loudness is not needed to hear everything.

DW

 

I would suggest dropping the crossover frequency and uping the gain on the sub. When the factory speakers (or any other speakers) and the sub are both playing the same frequencies and it tends to sound muddy. Either put a cross over or bass blocker on the factory speakers or drop the x-over freq on the sub so they don't compete. Try it and see what you think.