Vijay

My B7 RS4 Bose system is pretty decent for my ears, except for the substantial lack of bass. The 9" sub in the rear deck is a joke. Anyway.....I want to take the input wires directly from the stock sub and feed them to an aftermarket sub in the trunk either using a line level converter or feeding directly into an amp that accepts speaker level inputs. My bass preference is for tight, clean. I don't listen to rap whatsoever, but I do listen to a fair amount of hard, fast rock.

how much power and what size sub should I use? I also don't want to add a ton of weight.

I was thinking about a JL 10W6v2 with a 250 watt JL amp.

Any advice, input appreciated.

avincar

I concur with the selection of a single 10" woofer.

I can't say that I think a lot of adding a sub to the OEM Bose system. Many aftermarket subs will dramatically outpace the Bose system in output, so you are either underutilizing the sub or overusing it and sounding like a boom car.

I would go with a shallower woofer in a fiberglass enclosure behind the door on the driver's side of the trunk. Fiberglass enclosures are lighter than MDF if made properly. Putting it back there will save you trunk space too.

There are differing schools of thought on JL. I don't think a W6 will fit back there where I would put it, first off, but it might.

Many feel their woofers are overrated from an SQ standpoint.

I definitely believe that their amps are overrated and limited in their SQ as far as their cost goes.

I use Zapco amps a lot, I use DLS a lot, and I use DLS subs a lot. The new flat Rockfords are surprisingly good and work in very small enclosures. The IDQ 10" is good. The Alumapro 10" is good. Some like the Adire Brahma.

But the perception of bass is NOT just a subwoofer's job, it is also the midbass drivers' job. The sub bass will get better, so the fundamentals of the kick drum will improve, but your snares really won't, and neither will your upper harmonics of the lower notes.

Any way to persuade you to do a 4-channel amp and a new set of components up front?

Oh, and disconnect the center channel. Seriously.

Vijay

So, no, I'm not going to do anything more to the RS4 than to upgrade the sub. If the 10W6v2 is going to be overkill for this application, however, maybe I'll go with the 10W3v3. If such a sub is still underutilized in onjunction with the Bose, that's okay. It is just so bass deficient now.

avincar

Let me guess, you have JL in the other car

Vijay

Sony JDM head unit
Focal speakers front/rear
JL sub
JL amps

Also had JL stuff in my B5 S4 before that. Happy with it and easily available a mile from my home.

avincar

So if you already knew what you wanted, were you looking for pats on the back or what?

MacSub

And you were seriously overcharged

reefer_bob

and it will totally overpower the mids and highs (obviously).

I like the system to get rowdy from time to time, so I keep things turned down a lot.

For rock in a small package, you might want to consider the 8w7. It's a beast.

I really like the 10w6, but not with the 250, I think you're mismatched. The 10w3 would be more suited for a 250.

The GF has a ported 10w1 with my old RF PunchPower 150x1, and its real nice and punchy in her Civic. Not quite enough, IMHO, that's why I'd reccomend the 10w3 with a little more oomph.

reefer_bob

Obviously decent bass can hide a lot of inadequencies of a mediocre system.

I think when tuned right, a nice sub/amp combo can make a Bose system sound quite nice.

It's not going to win any competitions or anything, but for a low cost, easy to install solution, I think it's a great idea!

avincar

The output of the Bose system in the midbass and low bass is poor in quality.

If you use a lower xover point and use the woofer as a true subwoofer, you are stuck with these deficiencies. Nothing is masked, nothing is covered up.

If you use a higher xover point, making the woofer louder and getting more impact from it, and masking the same notes from the Bose speakers, you pull the staging to the rear - ruining the stereo illusion. The drum kit is now in the trunk.

I'd rather have a good front stage and good imaging, and be missing the lowest octaves, than have low bass, but crappy staging.

Stereo is supposed to be about illusion. It doesn't have to be - in each of our cars we can make it about whatever we want - but it was invented to create an illusion of location in front of us.

What many people make it about is sensation - it's got a lot of bass! It's loud! It sounds like it's all around me!

But that's not what stereo is supposed to do.

I actually prefer doing systems that leave out low bass, but do a really good job on the mids and the highs, than the systems which do lots of low bass but shortchange the mids and highs.

I believe that with B6 and B7 A4/S4, and with A5 A3, the lowest-cost sound quality improvement you can make is to disconnect the center speaker and the factory subwoofer.

With the B5, the front speakers are so deficient in any low end, adding a woofer makes a huge difference - but upgrading the F door speaker size can make a huge difference too.

Your Bose speakers have deteriorated quite a bit in the last 5-7 years. It's hard to think that something new wouldn't do you better. I'd even use the DIY drivers I've posted from Madisound and drop them into the Bose locations and run them off the Bose amp. Be a huge improvement.