DIY: Speaker and Subwoofer upgrade. Harman Kardon based System

[Technic]

Originally Posted by dkuznetsov92

What will happen if I drop this subwoofer in with stock amp?

Your HK OEM amp will overheat.

[whatheheck]

My understanding is - stock HK Amp was not designed to handle resistance/ohms lower than 7 ohms (stock subwoofers are 7.2 ohms each).

SWS subs are 4 ohms each so if you hook it up to the HK amp the HK amp will get really hot and most likely will shut down or get damaged after a certain amount of playing time.

Dan

Originally Posted by dkuznetsov92

What will happen if I drop this subwoofer in with stock amp?

[emfo]

Originally Posted by whatheheck

My understanding is - stock HK Amp was not designed to handle resistance/ohms lower than 7 ohms (stock subwoofers are 7.2 ohms each).

SWS subs are 4 ohms each so if you hook it up to the HK amp the HK amp will get really hot and most likely will shut down or get damaged after a certain amount of playing time.

Dan

If I found a good subwoofer that was 7 ohms, then I should be able to use the stock amp?

[Technic]

Originally Posted by emfo

If I found a good subwoofer that was 7 ohms, then I should be able to use the stock amp?

Yes, you could as long as that sub is less than 2" deep. Otherwise it will not fit.

[whatheheck]

Yes you can but I dont recommend it.

My opinion - Stock HK amp is simply not powerful enough to drive subwoofers hard.

I tried it already. I hooked up two sets of 4 ohms subwoofers hooked up in series to each channel just to hear what the HK amp sounds like driving after market subs and I was not happy with the bass sound quality. Its simply not as tight bass and not as powerful bass that I would like it to be.

You can try it but I dont think you will be happy either and most likely will upgrade again later.

I recommend upgrade to a good dedicated subwoofer amp and better after market subwoofers to match the after market amp. I assure you you will be pleased with the results.

My set up sounds really really good. I demo it to my friends and family often and they are all smiles once they hear it and gives the upgrade two thumbs up.

My 2.5 cents opinion.

Dan

Originally Posted by emfo

If I found a good subwoofer that was 7 ohms, then I should be able to use the stock amp?

[Go_Vols]

Dan -

Request for clarity - I've got the big picture, but want to make sure I'm not making any foolish assumptions on the details:

1. You pick up factory HK system signal by connecting to the wiring near the stock sub location (you identified that you used a "disconnect connector" in your picture). Are there 2 connections here for the signal inputs or just a single?

2. You then run wiring back to the LOC from this source, along the doorsill and through the interior to the trunk... process signal, connect to amp, amplify, yada, yada... all the magic happens....

3. Did you then re-run the freshly amplified wiring back to the front to through the same access path?

4. Finally, did you run fresh wire amongst the new subwoofer inputs in order to achieve the proper ohm resistance? Was this run under the carpet or some similar method between the seats?


Thanks in advance, and sorry to pull this back to the present... but you seem to have put together a system you're extremely happy with for a rather tidy $1300... color me intrigued!

Thanks,
Todd

[whatheheck]

Hi Todd.

Here you go.

1)Unplug the stock subwoofer connectors. (There are 2 wires inside the connector. Positive and negative.)

2) Replace stock subwoofers with SWS subwoofers.

3) You can either use a connector disconnect like I did or simply cut the original BMW subwoofer connector. Taking note of positive and negative wires - splice new wires on the stock subwoofer connectors and run those new wires towards aft of the car. These wires will be input to the Line Output Converters. Do this for left and right channel subwoofers.

If you did the driver side first - do the same for the passenger side subwoofer.

4) Line Output Converter RCA output will go to your New Subwoofer Amp's RCA input.

5) Your new subwoofer speaker output: Run new wires from your new subwoofer amp output towards the front of the vehicle heading towards under driver and passenger seat. These new wires from your new subwoofer speaker output will now plug in to your new SWS subwoofers.

Remove the rear seat and run these new subwoofer wires to the same wire run on the side of the car. Run the wires under the door sill as my picture shows, then cross it heading towards the subwoofers.

6) Do the gain level setting as I mentioned on the post above. This is very critical for a nice sounding & tight bass.

Hope that helps. If something is still not clear go ahead and post and I will try my best to help you.

Or come over my house one Saturday and I will help you.

Dan

Originally Posted by Go_Vols

Dan -

Request for clarity - I've got the big picture, but want to make sure I'm not making any foolish assumptions on the details:

1. You pick up factory HK system signal by connecting to the wiring near the stock sub location (you identified that you used a "disconnect connector" in your picture). Are there 2 connections here for the signal inputs or just a single?

2. You then run wiring back to the LOC from this source, along the doorsill and through the interior to the trunk... process signal, connect to amp, amplify, yada, yada... all the magic happens....

3. Did you then re-run the freshly amplified wiring back to the front to through the same access path?

4. Finally, did you run fresh wire amongst the new subwoofer inputs in order to achieve the proper ohm resistance? Was this run under the carpet or some similar method between the seats?


Thanks in advance, and sorry to pull this back to the present... but you seem to have put together a system you're extremely happy with for a rather tidy $1300... color me intrigued!

Thanks,
Todd

[Go_Vols]

Last question - does this diagram properly display the sub speaker wiring approach you utilized?



Edit: Appreciate the offer to help, but Everett - while beautiful - is a bit of a haul from Houston for such a minor chore!

[whatheheck]

Hi Todd,

Depending on the subwoofer amplifier that you are using.

Some subwoofer amplifier have Left and Right channel output, although the outputs are wired in parallel inside the amp.

So, if your subwoofer only has one output (positive and negative) then you hook up your subwoofers in parallel.

If your subwoofer has stereo output / Left and Right Channel = then hook up left channel output to driver side subwoofer and right channel subwoofer amp output goes to the passenger side subwoofer.

Hope that helps.

What subwoofer amplifier are you using? Let me know so I can provide a better answer for you.

I will try and draw a schematic diagram and post it here once I get home from work tonight.

Dan

Originally Posted by Go_Vols

Last question - does this diagram properly display the sub speaker wiring approach you utilized?



Edit: Appreciate the offer to help, but Everett - while beautiful - is a bit of a haul from Houston for such a minor chore!

[Go_Vols]

I'm planning to copy your recipe. JBL Amp.

[whatheheck]

I actually used my old Sony subwoofer amp. This Sony Sub amp pumps really hard and really clean tight bass.

I did install JBL Amp on my Ferrari 360 Spider and very happy with it too.
Same. Clean, tight sound.

So, if you will be using the JBL GTO-751EZ Monoblock GTO Series Class D Car Amplifier. That amp can handle down to 2 ohms (750W RMS x 1 channel at 2 ohms). So yes, you can wire your SWS Subs in parallel.

Once you have amp hooked up to the subs and if you find the subs too loud and too powerful even at very low volume then you can wire the SWS bus in series. Its up to you, you can experiment on what works best for youo.

Here's a schematic I created. Hope that helps.

Dan

Originally Posted by Go_Vols

I'm planning to copy your recipe. JBL Amp.

[Aziego]

Following the lead from OP, I finally gathered enough courage and did something about the bass in the car. I contacted Whattheheck for some pointers and he has nothing but helpful. Anyway here is my setup:

Technic Harness & LC2i - Makes the installation little easier (I guess? It was a b*tch taking the trunk lining off).

Soundstream Picasso PN5.640D - this is a 5 channel that I am running as a 3 channel setup 1&2 and 3&4 are bridged to feed the underseat woofers. Output is 160W to each woofer and 350W for the subwoofer.

Jehnert underseat woofers - I originally bought these speakers over half a year ago but never got the courage to install them.

JL Audio 10W0V3-4 10" sub in a custom built box. I designed the box to be a wide wedge, this is so that I do not lose too much trunk space. I plugged the JL audio recommended dimensions in a spreadsheet and start playing with the dimensions while maintaining the same internal volume. It is absolutely not the right way to go about it but seems to work.

Below is the obligatory picture of my setup. Excuse the messy wires, I am waiting on wire wraps to arrive, then I will tidy it up.

[Mandi90TT]

That looks like a lot of trunk space lost to me, but glad to see someone else digging into BMW M4 audio

[Aziego]

Nothing will compare to the musicnw box but the space lost is really not too bad. Especially since I rarely put anything up against the backseat. Case in point, made a Costco run without issues

[MSportTune2]

Originally Posted by whatheheck

Here is a short 1 minute audio / video. Clean sound, nice and tight and powerful bass.

I am going on a long drive again this weekend and will crank it up and drive it hard and see if the Sony amp gives up. As I mentioned I've got the amp installed now for over 2 weeks, every time I go out for a drive I crank it up and drive the Sony amp really hard and so far so good.

Perhaps this Sony amp is more tolerant to over voltage input. Or I am just getting lucky.



Dan

Awesome! Level 42

I have not heard this version of their song before though I have the standard and remix version.

[whatheheck]

Glad to hear I was able to help you.

How do you like the sound of your upgraded system? I bet it sounds great.

The subwoofer box seems a little big for me too but as long as you are happy with it that's all that matters. Make sure the sub is fully secured back there too for safety reasons.

Looking forward to hearing how you like your new setup.

Dan

Originally Posted by Aziego

Following the lead from OP, I finally gathered enough courage and did something about the bass in the car. I contacted Whattheheck for some pointers and he has nothing but helpful. Anyway here is my setup:

Technic Harness & LC2i - Makes the installation little easier (I guess? It was a b*tch taking the trunk lining off).

Soundstream Picasso PN5.640D - this is a 5 channel that I am running as a 3 channel setup 1&2 and 3&4 are bridged to feed the underseat woofers. Output is 160W to each woofer and 350W for the subwoofer.

Jehnert underseat woofers - I originally bought these speakers over half a year ago but never got the courage to install them.

JL Audio 10W0V3-4 10" sub in a custom built box. I designed the box to be a wide wedge, this is so that I do not lose too much trunk space. I plugged the JL audio recommended dimensions in a spreadsheet and start playing with the dimensions while maintaining the same internal volume. It is absolutely not the right way to go about it but seems to work.

Below is the obligatory picture of my setup. Excuse the messy wires, I am waiting on wire wraps to arrive, then I will tidy it up.

[whatheheck]

Thanks! Great band indeed.

Dan

Originally Posted by MSportTune2

Awesome! Level 42

I have not heard this version of their song before though I have the standard and remix version.

[64-bit]

Originally Posted by dkuznetsov92

What will happen if I drop this subwoofer in with stock amp?

I also want to know! The BavSound upgrade is $500 just the woofers alone.

[DKX4///M]

I too use the
LCi2 to power 12" RF P3s w a Pioneer 2400w mono amp in 2 separate vented boxes stuff w polyfill....entire trunk is sprayed under the stock lining w boom matt....

the 2nd "non bass " set of RCAs are hooked to 2/4 channel 600w KICKER AMP. Because i grabbed the thicker stock sub wires coming out of the OEM AMP n DSP I Have a feeling they are filtered so going bring kicker to 2 channels n power underseat subs w 150rms each...most likely upgrade the oem speakers...

i have a 2nd LCi2 im going to grab door speaker full range use 1 set RCAs to power all fronts, other all rear....use 2 smaller amps instead of one large so i can use front/rear fader...what sizes are oem door speakers n rear? resistance ? peak power handling? freq range?

also anyone try LCI6 7 OR 8? i think using them post Dsp system n amp will allow oem dsp tocontinue to work...

[JMon]

If we want the most bass out of the current under seat setup,
(Given this is now a year old)
is this still the best route to take? SWS8x + External Amp?
or is the new BAVSound setup better?

Anyone get one of these to work?
Pioneer TS-SW2002D2
Rockford P3SD48 P3
Rockford T3-BMW-SUB

[4everkidd]

Originally Posted by Technic

Your Sony aftermarket amp accepts up to 16V of high level inputs. Your HK OEM amp outputs 30V+ peaks, and about 21V on average.

Your Sony amp will be damaged.

No aftermarket amp high level inputs currently in the market can handle the HK OEM amp woofer outputs in the short or long run.

An Engineer should have caught this...

[BMWAUDIO]

I 100% agree w/ Technic on this one . do yourself a facvor and buy an audicontrol LC2I
http://www.audiocontrol.com/car-audi...-upgrade/lc2i/

Eventually you will damage your sony amp no big deal but you can also damage your stock Hk amplifier and possible cause a short and damge your wiring


THE Rockford T3-BMW-SUB Is a much better sub but it is more expensive

Originally Posted by Technic

Your Sony aftermarket amp accepts up to 16V of high level inputs. Your HK OEM amp outputs 30V+ peaks, and about 21V on average.

Your Sony amp will be damaged.

No aftermarket amp high level inputs currently in the market can handle the HK OEM amp woofer outputs in the short or long run.