Intellilink R4.0 external amplifier and custom subwoofer installation

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B52
Posts: 12
Joined: Wed Jun 05, 2019 11:51 am
Astra Model: Astra K Sport Tourer '18 - 1.4T 125ps
Astra Colour: Cosmic gray ("You Drive Me Crazy" on HUN market)

Intellilink R4.0 external amplifier and custom subwoofer installation

Post by B52 » Sun Oct 27, 2019 1:07 pm

Dear K owners!

I thought I will summarize the experiences of my sound improvement project.

---INTRODUCTION---

I've read a lot of threads and tips for subwoofer and external aftermarket amp installation on many german and english forums for ASTRA K but I did not find exactly what I was looking for. So I just went on it my way.
My car is a 2018 Astra K Sport Tourer 1.4T 125ps with INTELLILINK R4.0 multimedia head unit. All the "tutorials I found earlier were about cars and connections of NAVI900, which are sligthly different from this one.
So the R4.0 looks like this:
Image
My car is a company car that will be mine for about 6-8 years, and I use it about 1-1,5 hours a day. And I need quality music for this.
I AM NO PROFESSIONAL! It was a fun DIY project, but I tried to do my best to make some quality job. I only had time for the project after work and on the weekends, so it took me a very long time.
I hope you'll like it.

---PROBLEMS---

The car has the so called "6 speaker premium sound system". Yeah...premium...
However the sound quality was not SO bad at normal volume, but with some EQ settings the speakers woud not make it on higher volumes and all the low end frequencies were lost while driving because of wind and tyre noise. The quality and volume of rear door speakers are rather a bad joke. i could barely hear them.

--- AIMS---

So the main aspects:
- ~300 EUR budget
- !all the modifications must be reversible and no destructive steps are allowed! (as it is company car with warranty)
- improve rear door speaker quality and volume
- improve bass
- preferring non visible modifications
- minimalize boot capacity loss

---CONCEPT---

My first idea was to keep the 4 door speakers and add a subwoofer to the system.
Option1:
Add a spare tyre sub like the BOSE one in Mazda 6. (~70EUR used., built in amplifier, ~50W power) with a LOC (high to low level converter) converter (~10 EUR low quality, ~30-50 EUR good quality) and some DIY wiring.
pros:
- super cheap and sleek solution
- easy to get one
- pretty good sound (I listened to it in a Mazda)
cons:
- needs wire cutting
- not a very big performance
- low frequencies still remain on door speakers, so little quality improvement but no volume improvement
- a chance to get a defective sub can add costs easily
- (not a real con, but made me hesitate) if the impedance of LOC somehow does not fit the impedance of speaker system - which I still didn't find information about, 6 or maybe 4 ohms - that can damage the Intellilink R4.0s amplifier which can screw up everything

Option2:
Same as option1 but with a JBL BASSPRO HUB spare tyre sub with remotebass knob.
pros:
-100W nominal performance, decent bass
-reliable specifications and manuals from a reliable source
-high level input
-remote bass knob
-no need for aftermarket (maybe low quality) LOC
cons:
-high price (~400EUR)
-door speakers still have bass on them, which limits volume improvement a lot

Option3:
Add a plug and play DSP amplifier to the system. Either try to find a 5 channel DSP amp or a 4 channel one with AUX output for a an active SUB.
pros:
-very elegant solution, no cutting if an Y splitter adapter cable can be found
-high pass filter and a lot of for door speakers can be set via DSP
-low risk at installation (impedance and others...)
cons:
- high price (~3-400EUR for the amp only or even more if it has 5 channels and more performance)
- amps in my budget have low performance
- found no used amps for sale in EU

Option4:
Keep door speakers and add an independent DSP with high level input hooked up with used 5 channel amp or 4 channel +2/1 channel amps.
pros:
- customizable sound in every aspect
- good quality high-low level conversion
- a bunch of cheap, good quality used amps around on the market
- amp and sub performance can be as much as I want
cons:
- a lot of very old amps out there
- DSPs are usually expensive
- DSP+4ch amp+2/1ch amp need a lot of space

Option5:
Same as Option 4 but replace door speakers as well. Front speakers with premium component 16,5" set and rear door speakers with 16,5" premium coaxial sets.
pros:
- the biggest improvement in sound setup
cons:
- need to tear down doors (might loose or break some plastics too)
- doubles the budget
- need adapters and brackets for new speakers as well

+1 option
Add sound insulation to the doors, floor, trunk and boot.
pro:
- more silent car
- promising big improvement in sound quality
cons:
- bags of money
- must tear down the whole car, which is very time consuming, might even damage something

--- DECISION---
After a lot of hesitation I went with option4, but I also extended my budget to ~400EUR. Fully customizable sound was very promising and had also kept the opportunity to install better door speakers later if needed (spoiler: It wasnt necessary).

So the concept was like this:

Névtelen.png

Get a DSP, amp and sub in the trunk and drive all the speakers from that new amp.


---PREPARATION---

The R4.0 does have different connectors like the NAVI900. It was very difficult to find a PARROT adapter. I learned that the R4.0 in the Astra K has the same connector as the R4.0 in Corsa E, so searched for that and found one on ebay from Poland. It was pretty expensive ~25EUR.
Image

R4.0 has brown and white connectors, we only need the brown one. The other end of the adapter is a standard ISO connection:

20190731_193610.jpg

For which we need additional ISO connectors which can be soldered to the wires :

20190730_205741.jpg

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All harnesses covered with textil-tape to prevent from rattling. This is the harness with the connector to the DSP, I added a fuse to the supply wire as well:

20190801_210819.jpg

The main harness was created of 4 pcs of 2x0,75mmˇ2 cables, so 16 wires altogether. 4 wires for pre amplified original signal to the dsp and 4 wires back from the trunk to the door speakers.

I lead the wiring to the trunk below the door sealings:

20190803_125950.jpg

Pardon, the DSP.
After a lot of research I decided to get an AUDISON BIT TEN D, which I got for about 150 EUR on a sale. It was a demo device in the shop.

20190730_192825.jpg

The BIT TEN D comes with a remote control, but also the simple BIT TEN would make it for me.
This device has high level input and a good computer interface to customize, more details later.

I decided to build a custom subwoofer box under the floor in the trunk.
I ordered a Hertz ES250.5 subwoofer to make it happen, which has nice characteristics and its depth was good for this. (ES 200 might be better for this, I would buy that one instead of the ES250 if I had to do it again).

20190730_192153.jpg


B52
Posts: 12
Joined: Wed Jun 05, 2019 11:51 am
Astra Model: Astra K Sport Tourer '18 - 1.4T 125ps
Astra Colour: Cosmic gray ("You Drive Me Crazy" on HUN market)

Cont: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by B52 » Sun Oct 27, 2019 1:47 pm

I had a super deal with amplifier. I bought a JBL GTO series 5355 5 channel amp for about 80 EUR.
It has super specifications and decent performance, not to talk about the size. I found information about the generator of the Astra, it tells that it has a 130A charging current. This amp has a maximum current consumption of 55A with 4 ohm speakers (as I have currently), so I decided it will be okay. I do not have Start stop in my car so it has a pretty small battery. I might add a 1F capacitor later if needed. (But this far I did not experienced flickering lights or anything else suspicious). I think amp would only consume about half of this current during my average everyday use.

20190730_192524.jpg

I made the cables for these too.

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I wanted to fit all the devices under the floor just like the subwoofer, so I made a deck for them.

20190731_192103.jpg

20190801_185627k.jpg

20190801_195731k.jpg

20190801_200819.jpg

20190803_103047.jpg

I had to modify it a bit, later.

B52
Posts: 12
Joined: Wed Jun 05, 2019 11:51 am
Astra Model: Astra K Sport Tourer '18 - 1.4T 125ps
Astra Colour: Cosmic gray ("You Drive Me Crazy" on HUN market)

cont2: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by B52 » Sun Oct 27, 2019 1:56 pm

Finished the cabling to the trunk.

20190803_130009.jpg

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20190803_142126.jpg

20190803_103047.jpg

20190803_103109.jpg

I fired it up and tested. Everything was OK, the 4 door speakers were working. Sound quality was terrible, but I was expecting this as no settings were done. Quick test passed.

Now it is time for the subwoofer.
The material I used for the box was 22mm MDF (3/4" MDF) and some sealing for the joints.
The woofer in a sealed box needed ~20 liter displacement, the shape of the trunk limited me a lot so I had to create a very advanced box shape as you can see in the pictures. About a whole weekend of cutting, measuring, checking and correcting followed. It was definitely the most difficult part of the project.

20190803_231132.jpg

20190803_231148.jpg

20190804_014444.jpg

20190804_015733.jpg

The final shape:

20190804_093324k.jpg


B52
Posts: 12
Joined: Wed Jun 05, 2019 11:51 am
Astra Model: Astra K Sport Tourer '18 - 1.4T 125ps
Astra Colour: Cosmic gray ("You Drive Me Crazy" on HUN market)

Cont3: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by B52 » Sun Oct 27, 2019 2:05 pm

---FINISHING---

And in the car, already covered:

20191027_100323.jpg

20191027_101103.jpg

Did not lost any boot capacity:

20191027_101325.jpg

20191027_101331.jpg

I fired it up to see whats up with the sound.
I was VERY UNSATISFIED with the result!
I was disappointed and blamed myself for the time and money I wasted.
It did not let me calm, so I jumped into customisation.
The BIT TEN scanned the original signal coming from the source and it made it clear what I was expecting.
The signal coming from the factory amplifier was strongly equalized. Yes, even when all the fader/balance and EQ settings on the R4.0 was set to default. Then I set up the BIT TEN to de-equalize the input signal. This way I could set up appropriate EQ setting for each speaker by myself.
The rear speakers barley got signal and the speakers (which sounded pretty good before) were like trash.
Then I found out that I can manage the volume problem of the rear speakers. One step closer.

A fow more attempts later I found a pretty good EQ and level setup for the frot and rear speakers and I have to tell you that the rear speakers are absolutely not so bad that I expected! It was the bad EQ and level setting of the factory amplifier that made it so trashy.
just have a look at the new EQ curve that give decent sound quality.

EQ curve for front speakers:

20191027_095622.jpg

EQ curve for rear speakers:

20191027_095633.jpg

Shocking, right?

I set up the high and low pass filters for the front/rear a sub and all.

---SUMMARY---

Now I have a satisfying music quality with more than enough volume. I am very happy with it. Sound is clear and loud, bass is shaking the chassis and the whole setup is invisible and reversible.

The project with all the accessories, cables, connectors and devices cost me about 420 EUR.



I dedicate this project and writing for my friend, who also helped me during the box fabrication and was super excited to hear it, but I sadly lost him in an accident before the project got finished.
RIP Balázs

bilboastra
Posts: 152
Joined: Mon Sep 10, 2018 9:51 pm
Astra Model: Elite Nav 1.4T 150
Astra Options: None
Astra Colour: Carbon Flash

Re: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by bilboastra » Sun Oct 27, 2019 5:13 pm

HI B52, I am sorry for your loss, thanks for taking the time to post this, it looks like a good setup.

I have added a small pioneer gm-d1004 amp under the center console and a small ksc-sw11 sub under my seat in my car and both have made a great improvement.

You are right about the rear speakers, I have been toying with the ideas of a dsp, I might get one now.

doradus
Posts: 39
Joined: Thu Dec 20, 2018 10:28 pm
Astra Model: Astra K 1.4T 150 Elite
Astra Colour: Granite Grey

Re: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by doradus » Wed Oct 30, 2019 9:42 am

Excellent post, given me some inspiration to do my own audio in the boot!

I’m sorry for your loss

B52
Posts: 12
Joined: Wed Jun 05, 2019 11:51 am
Astra Model: Astra K Sport Tourer '18 - 1.4T 125ps
Astra Colour: Cosmic gray ("You Drive Me Crazy" on HUN market)

Re: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by B52 » Wed Oct 30, 2019 10:03 am

bilboastra wrote:
Sun Oct 27, 2019 5:13 pm
HI B52, I am sorry for your loss, thanks for taking the time to post this, it looks like a good setup.

I have added a small pioneer gm-d1004 amp under the center console and a small ksc-sw11 sub under my seat in my car and both have made a great improvement.

You are right about the rear speakers, I have been toying with the ideas of a dsp, I might get one now.
Thank you!

Before this modification I tried the rear speakers with an external (non-car) amplifier and they were not SO bad as I thought earlier.
DSP can improve overall sound quality, but it also needs some patience :lol:

B52
Posts: 12
Joined: Wed Jun 05, 2019 11:51 am
Astra Model: Astra K Sport Tourer '18 - 1.4T 125ps
Astra Colour: Cosmic gray ("You Drive Me Crazy" on HUN market)

Re: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by B52 » Wed Oct 30, 2019 10:04 am

doradus wrote:
Wed Oct 30, 2019 9:42 am
Excellent post, given me some inspiration to do my own audio in the boot!

I’m sorry for your loss
Thank you!

Just do it! ;)
Post some pictures of the result when you finish! I am curious!

doradus
Posts: 39
Joined: Thu Dec 20, 2018 10:28 pm
Astra Model: Astra K 1.4T 150 Elite
Astra Colour: Granite Grey

Re: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by doradus » Thu Oct 31, 2019 10:22 am

B52 wrote:
Wed Oct 30, 2019 10:04 am
doradus wrote:
Wed Oct 30, 2019 9:42 am
Excellent post, given me some inspiration to do my own audio in the boot!

I’m sorry for your loss
Thank you!

Just do it! ;)
Post some pictures of the result when you finish! I am curious!
Just in the planning stages right now, and mine won’t be as elegant as yours 😂 I own the car so I don’t mind too much about looks and I’m after much more bass, so I’d probably have it proudly sitting in the boot hah

bilboastra
Posts: 152
Joined: Mon Sep 10, 2018 9:51 pm
Astra Model: Elite Nav 1.4T 150
Astra Options: None
Astra Colour: Carbon Flash

Re: Intellilink R4.0 external amplifier and custom subwoofer installation

Post by bilboastra » Tue Jan 14, 2020 12:03 am

B52 wrote:
Wed Oct 30, 2019 10:03 am
bilboastra wrote:
Sun Oct 27, 2019 5:13 pm
HI B52, I am sorry for your loss, thanks for taking the time to post this, it looks like a good setup.

I have added a small pioneer gm-d1004 amp under the center console and a small ksc-sw11 sub under my seat in my car and both have made a great improvement.

You are right about the rear speakers, I have been toying with the ideas of a dsp, I might get one now.
Thank you!

Before this modification I tried the rear speakers with an external (non-car) amplifier and they were not SO bad as I thought earlier.
DSP can improve overall sound quality, but it also needs some patience :lol:
What did you notice on the Dayton about the factory eq curve when set to flat on the head unit, is the bass exaggerated at lower volumes but cut at higher volumes and does the Dayton keep the eq you have set at different volume levels?

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