M3 CS / M4 CS stereo

[CanAutM3]

Originally Posted by swagon

SA676 HiFi Professional 205W
SA688 Harman Kardon 600W

I have the former in my F80 and it's barely alright. I don't care nor know THAT much about audio, but I think there is a rather noticeable difference between HiFi and HK in terms of overall loudness - with music playing through Bluetooth and Spotify at max quality - I have to crank it up quite a bit to get some proper untz untz going on. And speaking of untz untz, it does lack the bass of the HK system (which you can further adjust to your liking in iDrive).

Everyone's perception is different so best to try it out for yourself.

And the SA676 HiFi is the same in M4 and M4 CS, but American-market non-CS M4s do get HK as standard.

Would you happen to know if the M3 and M4 HiFi have the same wattage power? I am wondering since the M4's HiFi system has more speakers to power...

[Humdizzle]

Originally Posted by GodfatherNiko

Do you have any more insight on this? Would like to try it on my h/k.

https://f80.bimmerpost.com/forums/sh...1322442&page=2

[swagon]

Originally Posted by CanAutM3

Would you happen to know if the M3 and M4 HiFi have the same wattage power? I am wondering since the M4's HiFi system has more speakers to power...

Every BMW document I could find points to the fact that the F32's SA676 HiFi system consists of 9 speakers and that the wattage is 205W - identical to the sedan. BUT, the F32 did get its own SA676 HiFi amplifiers and none were shared with F30. Harman Kardon amp is indeed shared between F30 and F32.

Could you please snap a pic of your rear parcel shelf and stick your head behind the rear seats whether any music is really coming out of the alleged mid-range loudspeakers. ETK implies that that the real parcel shelf is the same for all vehicles, no matter the audio system, which is definitely incorrect. It does not recognise the part number of a non-Harman Kardon rear window parcel shelf, for whatever reason.

However, I am quite certain the SA676 HiFi system does not feature a front mid tweeter. So that'd be 11 speakers instead of 9. Where did you find that it's got also the center tweeter?

This is doing me head in, man...

Attached is a wiring diagram for F32 HiFi with ASD, and F30 audio options. M3/M4s with HK have a separate ASD module that can be plugged off unlike those with HiFi. I had to code ASD out on mine.

[CanAutM3]

Originally Posted by swagon

Every BMW document I could find points to the fact that the F32's SA676 HiFi system consists of 9 speakers and that the wattage is 205W - identical to the sedan. BUT, the F32 did get its own SA676 HiFi amplifiers and none were shared with F30. Harman Kardon amp is indeed shared between F30 and F32.

Could you please snap a pic of your rear parcel shelf and stick your head behind the rear seats whether any music is really coming out of the alleged mid-range loudspeakers. ETK implies that that the real parcel shelf is the same for all vehicles, no matter the audio system, which is definitely incorrect. It does not recognise the part number of a non-Harman Kardon rear window parcel shelf, for whatever reason.

However, I am quite certain the SA676 HiFi system does not feature a front mid tweeter. So that'd be 11 speakers instead of 9. Where did you find that it's got also the center tweeter?

This is doing me head in, man...

Attached is a wiring diagram for F32 HiFi with ASD, and F30 audio options. M3/M4s with HK have a separate ASD module that can be plugged off unlike those with HiFi. I had to code ASD out on mine.

Honestly, now I am completely confused. When I look up the ETK I see different than what I saw this morning, maybe I did not have enough coffee. I deleted my posts until I can see things clearly again to avoid misinformation

[spool twice]

Same, I Google and get conflicting info. Whatever the case, the Hi-Fi system sounds decent, even with the door speakers being behind the door panel.

[CanAutM3]

Originally Posted by spool twice

Same, I Google and get conflicting info. Whatever the case, the Hi-Fi system sounds decent, even with the door speakers being behind the door panel.

Agreed.

[swagon]

Something fishy is going on, though.

All the F32s with HiFi system I have looked at DO NOT have speakers on the rear parcel shelf, e.g. this 2017:



Can anyone with a CS please confirm that their rear shelf speakers are actually functional?

[CanAutM3]

Originally Posted by swagon

Can anyone with a CS please confirm that their rear shelf speakers are actually functional?

I just checked, and sound is definitely coming out of those rear shelf speakers. It sound as if they are only tweeters though. There is also clearly sound coming from inside the rear quarter panel cards as I can feel the bass vibration.

[swagon]

Originally Posted by CanAutM3

I just checked, and sound is definitely coming out of those rear shelf speakers. It sound as if they are only tweeters though. There is also clearly sound coming from inside the rear quarter panel cards as I can feel the bass vibration.

Thanks for coming back to me.

Interesting to say the least, the difference between coupe and sedan... No wonder it sound better in the M4, then.

[spool twice]

I don't feel vibrations in my rear door panel from mid-range and vocals like I do when I place my hand on the front door panels. The vibrations I feel form the rear door panels are more lower-frequency's, which makes me beleive it's vibrations transmitted from the underseat woofers. I do hear sounds coming out of the rear deck speakers.

[spool twice]

There is a member on the M3/M4 CS facebook group who is rebuilding an M4cs and had his rear side panels off. I took the opportunity to ask him about the speaker locations in the rear side.

The rear side panels do not have speakers. I'm trying to confirm with him if the speakers that are in the rear parcel shelfs are tweeters or the mid-range that should have been in the rear side panels that are on the standard M4/4 series Hi-Fi systems. It would be strange if they had 25 x 2 watt tweeters in there though, as to me it would sound like it would overpower the fronts so likely has the 4" mid-range in those locations.

So it appears to have the following:

- Center Channel 4" mid-range (unconfirmed wattage)
- A-Pillar 1" tweeter X2 (unconfirmed wattage)
- Front door panel 4" mid-range x 2 (25 watts x 2)
- Underseat 8" subwoofer x 2 (40 watts X 2)
- Rear parcel shelf unconfirmed 4" mid-range x 2 (25 watts x 2)

All speakers are 2 ohm ratings (vs 2 ohm for mid-range, 4 ohm for the subs on the "HK" branded one).

I do find it interesting that the Hi-Fi has a 2 ohm sub, would explain why the bass surprised me the most on a system only rated for 205 watts. I tested the frequency range using one of those test files from 20hz - 20k hz, bass response 20-100hz registers stronger than subsequent range, where it drops off and remains relatively linear in response from 100hz -8k hz, and starts to roll-off slightly between the 8k-10k hz range.

[ApexM4CS]

I'm not an audiophile but I had HK in my '15 M4 and prefer the HiFi sound on the '19 M4 CS. Some speakers are hidden under the carbon composite door so the entire door feels like it's moving with some heavy duty bass.

[Kief]

Originally Posted by ApexM4CS

I'm not an audiophile but I had HK in my '15 M4 and prefer the HiFi sound on the '19 M4 CS. Some speakers are hidden under the carbon composite door so the entire door feels like it's moving with some heavy duty bass.

I'm with this guy...I think the HiFi sound in my 2020 M4CS sounds great! Even better than the HK in my 2018 M3CS

[doug_999]

One of the cool things about the Hi Fi sound is you can get the amp upgrade from Bavsound and make your stereo sound better than HK for $1K.

But their amp does not work if you have the HK system.

[JLS_397K]

Originally Posted by CanAutM3

There are 3 levels of sound system offered in the F8X (worldwide options):

• Base
• HiFi
• HK

The M4cs does not get the "base" system, it's gets the "HiFi". The M4GTS gets the "base" system though.

Side note, Are you sure GTS gets base audio? or is it just reduced HK?

[CanAutM3]

Originally Posted by JLS_397K

Side note, Are you sure GTS gets base audio? or is it just reduced HK?

Yes, I am pretty sure. If you look at pictures of the M4GTS interior, you'll notice it doesn't even have the tweeters on the A-pillars.

As far as I know, there's no such thing as a "reduced HK".

[CanAutM3]

Originally Posted by spool twice

There is a member on the M3/M4 CS facebook group who is rebuilding an M4cs and had his rear side panels off. I took the opportunity to ask him about the speaker locations in the rear side.

The rear side panels do not have speakers. I'm trying to confirm with him if the speakers that are in the rear parcel shelfs are tweeters or the mid-range that should have been in the rear side panels that are on the standard M4/4 series Hi-Fi systems. It would be strange if they had 25 x 2 watt tweeters in there though, as to me it would sound like it would overpower the fronts so likely has the 4" mid-range in those locations.

So it appears to have the following:

- Center Channel 4" mid-range (unconfirmed wattage)
- A-Pillar 1" tweeter X2 (unconfirmed wattage)
- Front door panel 4" mid-range x 2 (25 watts x 2)
- Underseat 8" subwoofer x 2 (40 watts X 2)
- Rear parcel shelf unconfirmed 4" mid-range x 2 (25 watts x 2)

All speakers are 2 ohm ratings (vs 2 ohm for mid-range, 4 ohm for the subs on the "HK" branded one).

I do find it interesting that the Hi-Fi has a 2 ohm sub, would explain why the bass surprised me the most on a system only rated for 205 watts. I tested the frequency range using one of those test files from 20hz - 20k hz, bass response 20-100hz registers stronger than subsequent range, where it drops off and remains relatively linear in response from 100hz -8k hz, and starts to roll-off slightly between the 8k-10k hz range.

This seems to make good sense, where they simply relocated the the rear speakers.

[CanAutM3]

Originally Posted by Kief

I'm with this guy...I think the HiFi sound in my 2020 M4CS sounds great! Even better than the HK in my 2018 M3CS

This is a very interresting testimony from someone who just switched from M3cs to M4cs .

I was also pleasantly surprised with the sound quality of the HiFi system in my M4cs compared to the HK in my previous M4. I do find the HiFi lacks in top end power though for louder playing volumes though.

[spool twice]

I can agree with the top end balls-to-the-wall sheer volume, the HK is less likely to sound shrill and distort at very high volumes, although I do find the Hi-Fi can play loud enough.

I believe the Hi-Fi sound pressure is rated at 104dB whereas the HK is rated at 110dB.

I have not gotten mine to distort yet playing closer to 75-80% volume, but my EQ settings aren't exactly crazy either, but it does give it some good balanced sounds throughout the range:



I'm not sure if earlier Hi-Fi systems have EQ settings, research leads me to believe that the EQ settings became a feature on USDM cars with ID6, but I'm not sure if the ID6 on the standard 4 series has and EQ.

**EDIT** it appears the 676 hi-fi on the M4 is unique from other 3/4 series in that it it has an EQ feature where they don't.

[spool twice]

Originally Posted by swagon

Thanks for coming back to me.

Interesting to say the least, the difference between coupe and sedan... No wonder it sound better in the M4, then.

I posed a question on the 3/4 series forum asking if their Hi-Fi with ID6 has an EQ feature, none have this feature on their 676.

Additionally, the 676 Hi-Fi on on the M4cs has a surround sound on/off function, but some say this is only on MOST OEM amps only and not the 676 analog Amp.

When I look up Real OEM myself with my VIN, it does who a 676 amp, but somehow the M4cs's system is able to have a DSP feature

I wouldn't think that you can code in DSP on the 676 amp, but maybe I'm wrong? It doesn't appear that any other 676 system has an EQ or surround sound on/off like the M4cs has after looking through various BMW platforms.

[spool twice]

So...

This gets more interesting..

The M4cs actually has an HK amp with the digital MOST input signal (Pink and Brown wires to the right of the amp)..which would explain the availability of the EQ and also Surround Sound on/off.



so now the question remains, whats the true wattage of the M4cs sound system, and are they 676 Hi-Fi drivers or 688 HK drivers?

I'm leaning towards the 676 drivers because we dont' have the 688 metal dome tweeters on the A-pillars, they appear to be the standard 676 tweeters. Same for the center channel, it doesn't have a mid/tweet pair and only a mid range.

Since wattage is determined by the amp's output, does that mean that BMW is intentionally over-driving the speakers? The impedance between the 676 and 688 is enough to wonder (2ohm vs 4ohm drivers on the low frequency loud speaker).

The M4cs technically then has a 500watt sound system from the F83?

**EDIT** I just coded in the B&O surround sound system with some great results. So much more depth to the sound staging even in "studio" mode, and the bass now shakes the seats, the highs are crisp and never harsh. Everything sounds much cleaner at higher volumes, amazing!

I don't think we have full HK drivers though, it may simply be the underseat woofers are HK-branded units from the 688 while the rest of the speakers are from the 676 unit.

M4cs owners, I recommend this coding mod :-)

[CanAutM3]

Originally Posted by spool twice

So...

This gets more interesting..

The M4cs actually has an HK amp with the digital MOST input signal (Pink and Brown wires to the right of the amp)..which would explain the availability of the EQ and also Surround Sound on/off.



so now the question remains, whats the true wattage of the M4cs sound system, and are they 676 Hi-Fi drivers or 688 HK drivers?

I'm leaning towards the 676 drivers because we dont' have the 688 metal dome tweeters on the A-pillars, they appear to be the standard 676 tweeters. Same for the center channel, it doesn't have a mid/tweet pair and only a mid range.

Since wattage is determined by the amp's output, does that mean that BMW is intentionally over-driving the speakers? The impedance between the 676 and 688 is enough to wonder (2ohm vs 4ohm drivers on the low frequency loud speaker).

The M4cs technically then has a 500watt sound system from the F83?

**EDIT** I just coded in the B&O surround sound system with some great results. So much more depth to the sound staging even in "studio" mode, and the bass now shakes the seats, the highs are crisp and never harsh. Everything sounds much cleaner at higher volumes, amazing!

I don't think we have full HK drivers though, it may simply be the underseat woofers are HK-branded units from the 688 while the rest of the speakers are from the 676 unit.

M4cs owners, I recommend this coding mod :-)

And the mistery of the Frankenstein M4cs audio continues to unfold

Thanks for sharing your findings