I recently installed a new head unit into my W126 380SEC. Actually, this is the 3rd head unit I have installed looking for audio nirvana on a shoestring budget.
My reason for changing the head unit was that I wanted some of the modern functions of 2020’s. The head unit that came with the car was a Pioneer CD player that pre-dated bluetooth. This gave me a couplf of options:
- Source a Becker head unit from the era and add a bluetooth module
- Find a head unit that was understated enough to fit in the era but still had all the mod-cons
Well, it turns out I managed to get a Becker head unit from eBay long before I bought the 380 – and it was a bargain too! But the more I looked into this, the more I didn’t like the idea. Firstly any DIY solution I found would have meant disabling the cassette player, as that’s where the bluetooth module connects. Secondly, I’d still be stuck with 80’s technology and sound quality. So I quickly abandoned this idea in favour of a modern head unit.
Initially I went cheap – real cheap! $20 cheap!
I found a head unit on Ali Express that had a pretty full feature set for only $20. I installed this unit and was quite pleased with it. Some of the things I I really like about this head unit were the big volume button right in the middle and the front facing USB ports that meant I didn’t need to keep the ashtray open to access the power socket to charge my phone. It even came with an app to control the head unit that was nice and snappy and always worked – even if it did look like it was designed by a person with no experience in UI design.
Of course it didn’t take long for its shortcomings to surface – surprisingly none of these were quality related:
- The buttons were backlit but the labels were not, so changing stations or tracks at night time relied on me remembering what button did what function
- The equalizer display was fake, but didn’t really bother me too much
- Although it had bluetooth, it was only really good for streaming music. Using the bluetooth to make or receive calls was not an option as the built in microphone was complete rubbish and there was no option to install an external one. OK, this was a quality issue.
So a few months later I went back to Ali Express looking for another $20 special – but this time I wanted an external microphone input.
I know, this one is way more blingy and more expensive at $60, but I also got a dashcam and reverse camera plus 2 remotes in the bundle. Right off the bat I installed this connected to my Pioneer 4x100W amp – and this is where I found the first issue with this unit. It only has one pair of RCA’s and when I tried to connect the amp to them I would get a loud popping sound on start up. So I resorted to using the line level inputs to the amp.
Now considering I was using an external amp, I really had high expectations of this head unit – but I was quite disappointed with the sound quality. I had installed some Infinity 4×6 speakers in the front and rear of the car a few weeks earlier too, so I was really hoping for greatness here.
To make things worse the user interface was just not intuitive at all. It had a touch screen, but no simple and direct way to change source. So changing from radio to bluetooth meant tapping the power button (and it’s not a physical button) 5 times to go through to the right input. Also, plugging my iPhone into the USB port would cause the unit to crash. Oh, and I never did get around to installing that external mic!
So, I decided enough of this rubbish, I’m going to look at something from a name brand. One of the more popular options I’ve seen is the VDO/Continental head unit. And while certainly looks good and has the right options, I didn’t want to spend that much – at around $350 plus shipping it seemed a bit much when there’s plenty of options from other established brands at half that price or less.
That’s when I came across the Kenwood KMM-BT506DAB. It retailed at around $155 from a local store and ticked all the boxes for me:
- Reasonably priced
- Bluetooth and external microphone
- 3x RCA preouts
- DAB Radio
- Made by a recognized brand with full AU warranty and support
I’m really pleased with this one. The user interface takes a little while to get used to. We’re all so used to simple to use full graphical interfaces these days that the click and scroll interface of this unit is not so intuitive. Which brings me to the remote app. Remember the comments I made above about the app that came with the $20 head unit – it is leaps and bounds better than what Kenwood offers. This app was last updated 4 years ago and looks like it was designed by the blind cousin of the person who designed the Chinese app.
Where do I start with this? Bluetooth audio streaming connects really easily and seamlessly which is a plus, but the the app only works if the head unit has the IPOD BT source selected or if the USB cable is plugged in. So if you were listening to the radio when you were last in the car you need to hit source button a number of times to IPOD BT then the app will connect. Then you can go back to listening to the radio.
Once the app is connected, any input from the app is met with a long delay. There’s no real technical reason for this, since the Chinese app was instant. The app also lets you change radio settings like the screen colour, euqaliser settings and general settings on the head unit. Some of these don’t work at all – I couldn’t get the fader / balancer to work. Other settings that do work have a massive delay of 2-3 seconds which is extremely frustrating.
So overall, I love the head unit, but hate the app with a passion.
