Installed: Blaupunkt Bremen SQR46 DAB + Jehnert doorboards & speakers

[jussos]

Hi,

Thought I'd share my experience with in-car entertainment on my 500e.

I wanted something that sounds good but looks as original / 90's as possible, and one that has Bluetooth audio and phone calls, and something that's fairly simple.

Ended up with

• Jehnert full system (4-way speakers and door panels)
• Blaupunkt Bremen SQR DAB head unit
• Audison Prima AP 4.9 bit amplifier (serving 2 just channels in bridged mode)
• No changes on rear speaker setup, at least so far

The end result is good enough to be recommended.

• The setup looks original
  • Quality of craftmanship is good
  • The setup fools anyone who doesn't exactly know how a W124 door should look like to believe it's 100% original
  • Nothing sticks out from dashboard as the mids and tweeters are hidden under original grilles (the tweeter install requires work to get fully under the grille tho)
  • Forgot to tell Jehnert to drop their logo from the grilles :-/
• Audio quality is good, but serious EQ tuning is required as bass defaults to "way too little"
  • The amp has essentially a limitless digital EQ and DSP. Tuning takes place via PC based software.
  • I'd love deeper bass still, but just can't afford to break the interior due to a subwoofer. Sub in a trunk isn't for my liking either, as the trunk seems well sound-insulated.
  • In comparison, say, a modern Porsche with factory Burmester setup does sound a bit better to me (deeper bass) but this one can be tuned to be close.
• The Bremen headunit works, but BT connectivity reliability could be better: Does not always pair. Does not default the iPhone to take phone calls
  • Need to upgrade FW in hopes to improve

I was also considering driving all the speakers individually using the amp crossovers, but this would've required an 8 channel amp, with 4 of those channels driving a fair amount of punch (for the 6.5 woofers), so I stayed away for now but left the option to upgrade to such a setup later by purchasing another Audison Prima amp.
I also considered buying more high-end speakers separately but decided to start with Jehnert's as they seemed to know what they're doing fairly well. Staying with the current setup for now, tho as it's not bad.

Hope this will help someone looking at a fairly easy way to significantly improve the 500e ICE.

 

[Jlaa]

Ended up with

• Jehnert full system (4-way speakers and door panels)
• Blaupunkt Bremen SQR DAB head unit
• Audison Prima AP 4.9 bit amplifier (serving 2 just channels in bridged mode)
• No changes on rear speaker setup, at least so far

Awesome! Would love to hear more about your travails as you tweak it!

Forgot to tell Jehnert to drop their logo from the grilles :-/

You can peel it off. It just sticks there. I peeled mine off.

• Audio quality is good, but serious EQ tuning is required as bass defaults to "way too little"
  • The amp has essentially a limitless digital EQ and DSP. Tuning takes place via PC based software.
  • I'd love deeper bass still, but just can't afford to break the interior due to a subwoofer. Sub in a trunk isn't for my liking either, as the trunk seems well sound-insulated.
  • In comparison, say, a modern Porsche with factory Burmester setup does sound a bit better to me (deeper bass) but this one can be tuned to be close.

I was also considering driving all the speakers individually using the amp crossovers, but this would've required an 8 channel amp, with 4 of those channels driving a fair amount of punch (for the 6.5 woofers), so I stayed away for now but left the option to upgrade to such a setup later by purchasing another Audison Prima amp.
I also considered buying more high-end speakers separately but decided to start with Jehnert's as they seemed to know what they're doing fairly well. Staying with the current setup for now, tho as it's not bad.

Hope this will help someone looking at a fairly easy way to significantly improve the 500e ICE.

Oh, you are noticing the exact same thing that I did!!!

I have fiddled with a Jehnert system in my 500E and without a subwoofer, I was able to achieve very very deep and rich bass down to 37Hz (tested with iphone tone generator). 37Hz is pretty good for a couple of 6.5" midbasses.

In my experience the key was phasing. Not EQ. For months and months I fiddled with EQ and I was frustrated that I couldn't get good deep bass out of the system ---- and I did not want to add a subwoofer. The breakthrough came when I sat in the passenger's seat of my car and was listening to some music --- and I realized that the front passenger's seat got super deep bass ... while the driver's seat bass was weak! As well, I realized that the bass while sitting in the back seat was spectacular, while the bass in the driver's seat was lame.

I think the issue is that L/R midbasses are somehow out of phase due to OE placement and cabin architecture. In the old days people would try and solve the phase issue mechanically, by putting the midbasses in the lower front part of the door and use the footwells as a "resonance area". My opinion is that this is a coarse way to solve the problem, both aesthetically and because using footwell area resonance to cover up any nulls in midbass performance is a shotgun approach (not a targeted approach). You have no control over which frequencies to address.

To fix midbass phasing in a precise, elegant way, you will have to drive the midbasses separately from the dashboard midranges/tweeters (and hence you will need your 2nd Audison Prima amp ...... or just use 8 channel amp w DSP) and then make the DSP delay the info to your driver's side Jehnert midbasses.

This change made midbass performance in the driver’s seat go from disappointing to spectacular! ….. in a way that no amount of equalization could fix. At the same time, midbass performance in the front passenger’s seat went from good to not as good! That tells me the issue is certainly a phase thing.... I cannot explain though why I had to add sooooo much delay for the left midbass (5.2msec)

See here: OWNER - jlaa | Owners and Their Cars

 

[Jlaa]

I was also considering driving all the speakers individually using the amp crossovers, but this would've required an 8 channel amp, with 4 of those channels driving a fair amount of punch (for the 6.5 woofers), so I stayed away for now but left the option to upgrade to such a setup later by purchasing another Audison Prima amp.

By the way, I am driving the speakers as such with an 8x75W @ 4 ohm amplifier:

• Tweeters - 75Wx2 @ 4 ohms
• Midranges - 75Wx2 @ 4 ohms
• Midbasses - each midbass is 4 ohms, so I have each pair wired in parallel (four total) - 100Wx2 @ 2 ohms
• Rear Speakers - 75Wx2 @ 4 ohms

The power is more than enough.


Since your Audison 4.9 amplifier is 4x70W @ 4 ohms and 4x130W @ 2 ohms, you could do this to try it without spending any more money:

• Tweeters and Midranges - use Jehnert passive crossover - 70Wx2 @ 4 ohms
• Midbasses - wired in parallel - 130Wx2 @ 2 ohms (I am not sure if the Jehnert midbasses are 8 ohm or 4 ohm drivers)

 

[gsxr]

Jehnert 6.5" midbass are 4 ohm each, designed to be wired in parallel using their passive crossover, and supplying a 2-ohm load to an amplifier in their frequency range. I really need to upgrade my Jehnerts with active crossover and DSP to get the fix Jlaa described above...

 

[2phast]

Hi,

Thought I'd share my experience with in-car entertainment on my 500e.

I wanted something that sounds good but looks as original / 90's as possible, and one that has Bluetooth audio and phone calls, and something that's fairly simple.

Ended up with

• Jehnert full system (4-way speakers and door panels)
• Blaupunkt Bremen SQR DAB head unit
• Audison Prima AP 4.9 bit amplifier (serving 2 just channels in bridged mode)
• No changes on rear speaker setup, at least so far

The end result is good enough to be recommended.

• The setup looks original
  • Quality of craftmanship is good
  • The setup fools anyone who doesn't exactly know how a W124 door should look like to believe it's 100% original
  • Nothing sticks out from dashboard as the mids and tweeters are hidden under original grilles (the tweeter install requires work to get fully under the grille tho)
  • Forgot to tell Jehnert to drop their logo from the grilles :-/
• Audio quality is good, but serious EQ tuning is required as bass defaults to "way too little"
  • The amp has essentially a limitless digital EQ and DSP. Tuning takes place via PC based software.
  • I'd love deeper bass still, but just can't afford to break the interior due to a subwoofer. Sub in a trunk isn't for my liking either, as the trunk seems well sound-insulated.
  • In comparison, say, a modern Porsche with factory Burmester setup does sound a bit better to me (deeper bass) but this one can be tuned to be close.
• The Bremen headunit works, but BT connectivity reliability could be better: Does not always pair. Does not default the iPhone to take phone calls
  • Need to upgrade FW in hopes to improve

I was also considering driving all the speakers individually using the amp crossovers, but this would've required an 8 channel amp, with 4 of those channels driving a fair amount of punch (for the 6.5 woofers), so I stayed away for now but left the option to upgrade to such a setup later by purchasing another Audison Prima amp.
I also considered buying more high-end speakers separately but decided to start with Jehnert's as they seemed to know what they're doing fairly well. Staying with the current setup for now, tho as it's not bad.

Hope this will help someone looking at a fairly easy way to significantly improve the 500e ICE.

Although the trunk may seem hermetically sealed off from the cabin, it is definitely not. I used a Infinity BassLink T in my trunk and the amount of bass entering the cabin is actually overwhelming. The amount of space consumed by the BassLink T is also minimal compared to a conventional square/rectangular enclosure. Very well worth the upgrade.

 

[jussos]

Jehnert 6.5" midbass are 4 ohm each, designed to be wired in parallel using their passive crossover, and supplying a 2-ohm load to an amplifier in their frequency range. I really need to upgrade my Jehnerts with active crossover and DSP to get the fix Jlaa described above...

By the way, I am driving the speakers as such with an 8x75W @ 4 ohm amplifier:

• Tweeters - 75Wx2 @ 4 ohms
• Midranges - 75Wx2 @ 4 ohms
• Midbasses - each midbass is 4 ohms, so I have each pair wired in parallel (four total) - 100Wx2 @ 2 ohms
• Rear Speakers - 75Wx2 @ 4 ohms

The power is more than enough.


Since your Audison 4.9 amplifier is 4x70W @ 4 ohms and 4x130W @ 2 ohms, you could do this to try it without spending any more money:

• Tweeters and Midranges - use Jehnert passive crossover - 70Wx2 @ 4 ohms
• Midbasses - wired in parallel - 130Wx2 @ 2 ohms (I am not sure if the Jehnert midbasses are 8 ohm or 4 ohm drivers)

A huge thank you for all the info, and for the efforts you’ve done. Very valuable. I wouldn’t have guessed additional delay would help so much!

Will absolutely try this out. Do you think just my 4.9 amp, with the setup you described, would suffice as a permanent setup? It sounds like it would. I don’t need a ton of dB. And would be achieved with just some rewiring, instead of all the work of adding a second amp.

Again, thank you so much for the info!

 

[Jlaa]

It might work. Try it out first before adding another amplifier. Try to see if you have a midbass phasing issue, sit in various positions in the car and see if the bass changes a lot based on seating position.

The value is in controlling delay between the left and the right midbasses. That eats up two amp channel right there. Since the midrange and tweeters are so close to each other, I do not think there is a whole lot of value to actively amplify these four drivers and eat up another four channels. Using passive crossovers w the midranges / tweefers could work well and consumes only 2 amp channels.

The one thing you would definitely need another amp/dsp for, though, is if you want a little ambience. Since I actively amplify the rear speakers, I mix L-R (left minus right) mono to both rear speakers. The eliminates any sound that is common to both channels, like vocals. Then I low pass that L-R at 7000 hz and delay both rear channels another 20 ms. This adds ambience, but is not necessary.

 

[jussos]

It might work. Try it out first before adding another amplifier. Try to see if you have a midbass phasing issue, sit in various positions in the car and see if the bass changes a lot based on seating position.

The value is in controlling delay between the left and the right midbasses. That eats up two amp channel right there. Since the midrange and tweeters are so close to each other, I do not think there is a whole lot of value to actively amplify these four drivers and eat up another four channels. Using passive crossovers w the midranges / tweefers could work well and consumes only 2 amp channels.

The one thing you would definitely need another amp/dsp for, though, is if you want a little ambience. Since I actively amplify the rear speakers, I mix L-R (left minus right) mono to both rear speakers. The eliminates any sound that is common to both channels, like vocals. Then I low pass that L-R at 7000 hz and delay both rear channels another 20 ms. This adds ambience, but is not necessary.

Cheers, sounds good. Will try different seats first.

Thanks to your other posts, I also might try an MBT-RX (have one in another car) to test the diff in audio quality between the SQR46 and MBT.
Thank you again!

 

[744Brillantsilber]

Hey @jussos,
congratulations, what a nice setup! I bet it sounds very good too!

Since you have the first Blaupunkt SQR46 I have seen in a W124, I would like to ask a question if you don´t mind:
Does the antenna go up all the time (like with the stock MB radio) or does it only come up with FM selected (like with some other aftermarket radio)?

I would appreciate your answer!

 

[jussos]

Hey @jussos,
congratulations, what a nice setup! I bet it sounds very good too!

Since you have the first Blaupunkt SQR46 I have seen in a W124, I would like to ask a question if you don´t mind:
Does the antenna go up all the time (like with the stock MB radio) or does it only come up with FM selected (like with some other aftermarket radio)?

I would appreciate your answer!

Thank you!

The antenna goes up whenever the head unit is on. It would be nice if it only went up only when radio used, but not this one.

 

[744Brillantsilber]

Thank you!

The antenna goes up whenever the head unit is on. It would be nice if it only went up only when radio used, but not this one.

Hey @jussos,
Thanks you very much for your answer!

 

[maw1124]

Oh, you are noticing the exact same thing that I did!!!

I wonder if this is what the time correction does. I notice when I’m clicking through delay values, the bass response in the cabin changes. So rather than use purely the distance, I use the one closest to it that produces the best sound, if that makes any sense. I wonder if the difference is some phasing mechanism.

maw

 

[Jlaa]

I wonder if this is what the time correction does. I notice when I’m clicking through delay values, the bass response in the cabin changes. So rather than use purely the distance, I use the one closest to it that produces the best sound, if that makes any sense. I wonder if the difference is some phasing mechanism.

maw

YES EXACTLY.

When I was tuning the audio system, I spent several months over at DIYMA.com reading about the theory behind how to tune this DSP stuff. What I learned (if I remember correctly!) (distilled into simpler points here, because those guys get SUPER technical if you are reading the right stuff):

• Tweeters - brain uses LEVEL moreso than time to determine where something is coming from. So set time alignment to the proper distance and then tune by ear by adjusting the Volume Level between L and R.
• Mid Bass / woofers - brain uses PHASING (distance) to determine where something is coming from. So set the distance based on ear as you @maw1124 have done where the bass is strongest. Adjusting Level won’t do nearly as much.
• Midrange - try to use a combo of more level and a little bit of TA based on distance

After this is all set, you can try to fine tune with EQ, but it wont be perfectly flat response by a long shot. There will still be lots of nulls (where frequencies from different drivers mix to cancel each other out in the car). This is unavoidable, but focus on subjective, not objective results.

Of course all this in only possible if everything is independently amplified with its own channel - all tweeters, midrange, mid bass all separate.

FWIW you might try this - download one of those free tone generators for your phone. It makes your phone play one and only one frequency that you set - for ex 40 hz or 100 hz or 200 hz or whatever you choose.

That for me proved INVALUABLE to determinine how to tune the system. I could tell how changing alignment of the mid basses would move the nulls around in the frequency spectrum, and how (IMPORTANT) changing crossover points and slopes (6db/oct? 12? More?) also changes the way things sound around the xover points.

My system now could probably use more tuning by someone who teally knows what they are doing, but it has been good enough for me where I have been content not to touch it for a year or so now …..

PS - rear fill - from DIYMA - using your DSP, subtract R signal from L signal and feed that signal, mono, to the rear speakers, while delaying about 20ms. That subtracts out the voices, leaving just the ambient differential stereo signal. Makes a GREAT “3D effect” that is controllable for level by the fader.

 

[Duh_Vinci]

• Tweeters - brain uses LEVEL moreso than time to determine where something is coming from. So set time alignment to the proper distance and then tune by ear by adjusting the Volume Level between L and R.
• Mid Bass / woofers - brain uses PHASING (distance) to determine where something is coming from. So set the distance based on ear as you @maw1124 have done where the bass is strongest. Adjusting Level won’t do nearly as much.
• Midrange - try to use a combo of more level and a little bit of TA based on distance

This is a great way to explain the basics, thank you!

 

[maw1124]

This is a great way to explain the basics, thank you!

EXACTLY!! Well done @Jlaa and thanks most sincerely.

For others, this to me is the main reason to go for a modern head unit. @Jlaa has done it expertly using the original head unit. All of that work is now included in modern head units. Together we have bridged and explained the difference but arrived at the same place (more or less).

After that, it's plug and play speaker selection, and if you want a subwoofer the new HUs give subwoofer control. But you need a complete tear out to get there. If you don't require a subwoofer, you can keep your factory head unit.

FWIW, I ended up the same place in my '05 M3, where the modern head unit was the key to unlocking real subwoofer and DSP control, time alignment, etc. In the end, that was what it was worth. I got to the same place sound wise with the factory unit and different (BavSound) speakers. But to control it, you either need a new HU or new DSP amps. Your choice, same outcome, is how I sum it up.

maw