Sickler

After reading the posts on the sub woofer upgrade I decided to go one step further and upgrade the factory amp as well. I have the Premium Plus non BOSE system. Upgrades include an Alpine PDXV9 amp which powers all speakers plus the sub (100x4, 1x500). Replacing the amp required an Audio Control LC6 output converter. The sub is a single 10” Digital Design fitted it its own box (did not install a free air sub in the rear deck). I retained the factory speakers. I also kept the factory rear deck “sub” in its location for now. I have the sub crossed over @ 60Hz. Sending the full signal from the source to the factory speakers. My goal was a cleaner low end and not a bass machine though I get the latter when needed.

The result is great. I’m sure there will be those that lament that fact I kept the factory speakers. In my opinion they’re not that bad, but can get fatiguing at higher volumes. The Alpine amp allows me to play at higher volumes without the fatigue. The sub fills out the lower end beautifully even with the windows down at highway speed. 60Hz seems to be the sweet spot for me as 80Hz becomes a bit boomy and the factory system plays well between 60-80. The only drawback having the sub in the trunk (and only a single 10) you don’t get strong kick to the gut; it’s a bit muffled. Dropping the seats helps of course, but not practical.

In any case, I achieved my goal of a “much better” sounding system. My goal wasn't a reference system. Was about $700 in parts with the amp being the most expensive. I’m sure you could go a step down (75x4) and save some money but I've used this amp in my other vehicles and have been pleased… However in those vehicles I ripped apart the doors and installed aftermarket speakers, which I didn't want to do in my Audi. Just thought I’d share my experience and would recommend this upgrade to anyone not happy with the stock system. BTW – All components fit nicely on the cubby “shelf” in the truck where the factory amp is located. The installation was pretty much the same as was documented in the sub woofer upgrade (thanks sgroer!) so I won’t go into those details again but I’d be happy to post pictures or assist in wiring questions if anyone was interested.

looking@audi

Thanks for the summary and information on your audio upgrade. I may look into a project like this after the busy holiday season.

I'm surprised that you find 60Hz as the sweet spot for the sub crossover? I would be very surprised if the factory speakers can pay anywhere close to 60Hz with any authority or accuracy. I'm only guessing, however, I would think 120-180Hz would work much better.

Maybe the higher crossover seems boomy because of the sub location?

Please post any install pics if you have them.

Maverick61

Could you post pics and details of how you wired this? Did you just cut the wires from your factory amp - or did you have to run new ones to each speaker? I am a car audio neophyte - just know enough to be dangerous so any pics / guides would be quite helpful

Thanks

subterFUSE

Congrats on the install.

I think you made the correct move by upgrading the amplifier first before the speakers. People often overlook the importance of the amplifiers. If you run expensive speakers with a crappy amp, you can do serious damage to them. It's much more important to have good amplifiers than good speakers. You can always replace speakers in the future if you decide to. The stronger amp will give you the additional headroom you are craving, and cleaner power to the existing speakers.

I have a complete aftermarket system in my BMW right now. I replaced everything with high-end gear about 4 years ago. Not too long ago, I upgraded just the amplifiers to add more power... and also the ability to run my front speakers in active crossover setup. I have been ASTONISHED by the difference just the amp made to my sound quality... and I began with a seriously good amp. The new one just took it to a whole new level.

The point about your subwoofer crossover point is a valid one. I can definitely promise that your factory speakers will not have the ability to play well at 60Hz. The speakers I currently have in my car are capable of playing down to 60Hz, but they were $2400 for the pair. I keep my JL Audio 12W6 subwoofer crossed over about 80Hz with a shallow slope. Realistically, the factory woofers can probably play down to 125-150Hz before the response begins to drop off. So you may want to cross the subwoofer over at a higher point like 90-100 Hz, and use a shallow slope. I'm using 12 dB per octave Linkwitz. I also have a subsonic filter at 30Hz to protect the sub from over-excursion.

subterFUSE

I'm pretty sure he said he's running an Audio Control LC6 to take the signal from the factory amp and convert it. I'm doing the same thing in my car using an Audison BitOne.

Look up these pieces of gear on Google and you can get more details.

aj0408

Hi Sickler
I may need some advise from you. I have just ordered the HD 900, LC6i and DLS OA10d sub.

I have the question on the wiring. Can you guide me on to how to remove the wiring from existing amp and wire the new one in with LC6. I am guessing the following basic high level steps:
(is this source level or
1. Output from the source head unit will go to the LC6i (speaker level? Source level? i.e. are we getting rid of audi amp or keeping it?)
2. The output from LC6i will be the input to new HD900 amp
3. The speakers will be connected to the amp out.
4. The amp will be powered from the battery with a 60Amp in line fuse
5. The amp crossover frequencies will be adjusted.

If the above is correct, I need to know where the wires are for step 1 and 3. Any help will be much appreciated.


Thanks

subterFUSE

Sub location can cause "boominess" as can some other factors like box type and speaker phase. One option is to invert phase to see if this helps. Another option is to find the frequency where the boom is happening and EQ it down. If the box is ported, it will be very critical to use the proper crossover point because it's easier to damage a woofer with a port or bandpass vs. sealed.

In my experience, adding power to my JL Audio sub actually reduced the boominess. I went from 750 Watts x 1 with a JL Audio HD750/1 amp to running 1000 Watts x 1 with an Audison Voce AV5.1k amplifer. I've been running the subwoofer at very low gain on the amp because of the excessive power, and it sounds awesome compared to before.

Sickler

1. Factory amp is still physically there, just not used.
2. Yes
3. Yes
4. Yes. It's in the trunk so it's an easy connection.
5. Yes


Here's my issue. I had a local shop do install for me since tearing into wiring and doing a radio install lost fashion with me when I graduated college. In any case, I have no clue as to what the shop used to secure the amp to the "shelf" I cannot move the darn thing. Thought it would be Velcro or even double sided tape, but it's as if the thing is welded in place. I'll need to stop by and ask them what they did. Unfortunately for pics, the install was done very clean and the wires are not visible. It appears they tapped into the existing wires (did not cut them). All the OE wires are behind the amp and their isn't enough slack to pull them out to show which wire is for which. I'll stop by the shop this week and see if they can pull it and I'll take some pictures.

BTW - The sub is crossed at 80 not 60... Bad eyes...

subterFUSE

I'm not certain how the Audi amp looks, but most of the time there will be a digital cable of some kind from the front of the car to the factory amp, and then a wiring harness from the factory amp that has wires which go to the factory speakers.

There are some companies which develop preamp boxes which can grab the digital signal before it reaches the factory amp. An example of this would be the Mobridge. The Mobridge works with the MOST-Bus found in BMW, Mercedes etc... It gives you an Optical Digital stereo output which you can then use to feed aftermarket equipment.

The other option is to grab the factory amp's output at the speaker level by tapping into the wiring harness. This is what it sounds like your installers have done, and it is also what I am doing in my BMW.

aj0408

Thanks Much. I will try to capture some pictures as I am going through it and update this thread as well. Stuff is likely to arrive starting next week. Should be fun....