[Yam_440i]

Since we have all the right people in this thread, I had a separate question (don't mean to derail here)
I have base audio and i recently changed my base mids to HK and added door tweeters. I haven't upgraded the amp yet.

What system should I code my head unit to? Hi-fi or HK in order to get the best out of what I have for now

[Billfitz]

I don't think any coding you do to the head will have any effect if you don't have either the Hi-Fi or H-K amp. But since I don't have a base radio I can't say from personal experience.

[FastFrog]

From my understanding (and experience), this coding affects the equalizer. The "Stereo" coding is notably boosting the high freq to mitigate the lack of tweeters. Hi-fi and HK code use a flat equalizer, since the EQ aspect is handled by the amp.
Neither coding affect the output level, which remain high level anyhow.
Your best bet would probably be to try them all, but I'd suspect you'd have too much trebles with the Stereo coding.

Edit: a much more in-depth answer here: https://www.diymobileaudio.com/threa...n-most.437890/

[johnung]

Originally Posted by Billfitz

The gauge required is determined by the length of the wire and the speaker impedance. Even with the short run used with 2 ohm subs it's best to use 14 gauge wire. 16 gauge is OK with 4 ohm subs, 18 gauge is OK with 8 ohm. Copper is a must, but expensive cables don't work any better than zip cord.

Bill, what would the symptoms be if a 2-ohm subwoofer was not connected to the amplifier with a thick enough gauge wire?

So I'm thinking of two different configurations:

1) Using existing car wiring to underseat subwoofers.
Amplifier —> 5-6 feet of 16g/18g across trunk to —> 6" pigtail of 18g from TechnicPnP harness to —> 8-9 feet of 18g BMW wiring to —> 2-ohm subwoofers. (My HK system had at least 18g to subs.)

2) Using new wire directly from secondary amplifier to the underseat subwoofers.
Amplifier —> 12 feet of 16g stranded copper wire to underseat subwoofers.
(I know that it was 12 feet because I used a 25ft spool and had just enough to do the two runs to the two sub locations.)

Back when I installed my AudioControl ACM-2.300 I remember that the connectors on the amplifier (see photo) could just about handle 16g wire. If I had tried to install 14g wire I would have had to strip away the outer insulation and then set my wire stripper to 16g to strip away some of the copper strands to insert the end into the wire terminal on the AudioControl amplifier. Not sure how much that would effect the gauge issue.

[FastFrog]

Johnung, the very post you quoted made me reconsider the wiring options, which originally looked very similar to what you name option 1.
So, I moderately freaked out and decided to go for a full re-wiring, with 1.5 mm² (equivalent ~15,5 AWG) for everything but the sub, which will be fed by a generous 2.5 mm² (equivalent to a tad less than 13 AWG). I'll post picture of the resulting harness, in case anyone is interested. My harness is going to fit Stereo-equiped cars and take front and rear high-level input from OEM connectors. No original wire will be harmed in the making of that audio...

[Billfitz]

Unless the gauge was seriously small you probably wouldn't notice the effect of wire smaller than ideal. What occurs is insertion loss, as the delivered voltage is reduced due to the resistance of the wire being too high relative to the impedance of the speakers. A couple of dB isn't really audible, but it does waste amp power. If you need to strip away a few strands of 14ga to fit into the amp connectors that won't affect the overall resistance of the full run of the wire.

While on the subject, I've wondered why the H-K woofers are 8 ohm. One possible reason is to keep the wire gauge small. There's a lot of wire in these cars, which adds up to a lot of weight, the sum total of which will affect fuel economy. The higher power of the H-K system results in higher current, which also requires a heavier gauge wire, unless you increase the speaker impedance to compensate, while increasing the voltage swing capacity of the amp to drive the higher impedance load. It's the only reason I can think of that justifies going with 8 ohm woofers.

[Revoltos]

Hey Bill. I have been reading your posts regarding hifi upgrades and have dutifully followed the sound advice you have given out. Im running base sterio currently on a nbt evo HU and ive decided enough is enough with the crappy sounds.
So far I have purchased:
HK front tweeter pods and tweeters
A Match 7dsp amp/dsp with required leads etc.
Im UK based and purchased the amp new from a shop on Ebay. I mentioned to the seller I was looking at the Earthquake subs you suggested and he kind of scoffed at it and suggested Musway (CSB4.2C 120 watts) I dont know you but I do value your knowledge and opinion on these things so I wondered what your views were on both musway subs and a possible musway replacement for my base mids. (Musway CSB8W 180watts).
What would you suggest as an alternative to the mids for my doors?
Thanks for your time.
John

[Billfitz]

The Musway are just run of the mill, nothing out of the ordinary. I'd use OEM H-K mids, bought used. There's plenty of them on the market, sold by twits who believed the hype from sellers like the one you dealt with.

[johnung]

Originally Posted by Revoltos

Hey Bill. I have been reading your posts regarding hifi upgrades and have dutifully followed the sound advice you have given out. Im running base sterio currently on a nbt evo HU and ive decided enough is enough with the crappy sounds.
So far I have purchased:
HK front tweeter pods and tweeters
A Match 7dsp amp/dsp with required leads etc.
Im UK based and purchased the amp new from a shop on Ebay. I mentioned to the seller I was looking at the Earthquake subs you suggested and he kind of scoffed at it and suggested Musway (CSB4.2C 120 watts) I dont know you but I do value your knowledge and opinion on these things so I wondered what your views were on both musway subs and a possible musway replacement for my base mids. (Musway CSB8W 180watts).
What would you suggest as an alternative to the mids for my doors?
Thanks for your time.
John

Billfitz is the most knowledgeable guy that I've met in many decades of being involved one way or another in audio. The audio industry has always been mired in marketing nonsense because they know that their average customer cannot discern between fact and sales pitch. It's a shame because the companies that make weak products but who lie the best often make a lot more money than the honest companies with excellent products.

I really like the way that Billfitz avoids the marketing hype and goes right to analyzing a product's technical specifications. I've been following Bill's advice for several years and he has been dead on.

Anyone else who I talk to about BMW audio is either trying to sell some other audio product that they make money on, or they aren't really knowledgeable. Most of the time, it's both!

Attached are photos of info/specs on the subs that you mentioned.

[johnung]

Originally Posted by FastFrog

Johnung, the very post you quoted made me reconsider the wiring options, which originally looked very similar to what you name option 1.
So, I moderately freaked out and decided to go for a full re-wiring, with 1.5 mm² (equivalent ~15,5 AWG) for everything but the sub, which will be fed by a generous 2.5 mm² (equivalent to a tad less than 13 AWG). I'll post picture of the resulting harness, in case anyone is interested. My harness is going to fit Stereo-equiped cars and take front and rear high-level input from OEM connectors. No original wire will be harmed in the making of that audio...

I'm not really sure what you mean by a complete rewire. The topic of conversation was the gauge of the wire to the Earthquake SWS-8Xi subwoofers because they are rated at 2-ohm. None of the other speakers in question are 2-ohm, so wire gauge is much less of an issue to the rest of the car's speakers.

Also I pointed out the lengths of the various wire sections from my install of my Earthquakes, but I should have also noted that those lengths are considered pretty short, not very long at all.

[johnung]

Originally Posted by Billfitz

Unless the gauge was seriously small you probably wouldn't notice the effect of wire smaller than ideal. What occurs is insertion loss, as the delivered voltage is reduced due to the resistance of the wire being too high relative to the impedance of the speakers. A couple of dB isn't really audible, but it does waste amp power. If you need to strip away a few strands of 14ga to fit into the amp connectors that won't affect the overall resistance of the full run of the wire.

While on the subject, I've wondered why the H-K woofers are 8 ohm. One possible reason is to keep the wire gauge small. There's a lot of wire in these cars, which adds up to a lot of weight, the sum total of which will affect fuel economy. The higher power of the H-K system results in higher current, which also requires a heavier gauge wire, unless you increase the speaker impedance to compensate, while increasing the voltage swing capacity of the amp to drive the higher impedance load. It's the only reason I can think of that justifies going with 8 ohm woofers.

The more that I work on my F30 BMW, the more apparent the design criteria become. Whether it's brakes, suspension, or audio systems, when they decide that the F30 will have a certain range of components then they design with all of them in mind. They save money building the cars at the factory if they can make them as similar as possible using as few SKUs as possible.

They want to avoid having too many different wiring harnesses, etc. They didn't want to design and inventory two center channel speaker brackets. So someone with a HiFi system can pop off their dashtop center grill and find an empty bracket to install a tweeter. Or someone without a rear tweeter can pop off the rear door card and find the tweeter location embossed in the rear side of the panel.

Who knows? The wire gauge logic may have gone exactly how Bill imagines. Or it could also have something to do with minimizing SKUs to go with the HiFi or Base audio systems. Tough to figure out what was going on ten years ago in the bowels of BMW engineering. 😀

[Revoltos]

Bill and Johnung kudo to you both. Thanks for the clarity (& specs John)
The chap didn't hard sell those Musway but said they have good experience with them in beemers but if they are a dealer for them, then they would do!
So Bill, you say stick HK's in to replace the base papercone jobbies, dont recommend anything else, gladon, focal etc ?

Cheers guys.

[FastFrog]

@johnung: You are right, I overstated when I said 'complete' rewire. I will still use the stock stereo wiring from the head unit as front and rear high-level Input. And I won't disassemble the wiring running inside the door panels.
Other than that, I will create a custom wiring:
- From the amp to the 2 subs and 5 mids as Outputs
- To the amp from respectively the underseat sub connector sub and rear mid connector as front and rear Inputs.
My subs are also rated at 2 ohms, reason why I didn't want to mess with gauge on them. All the other channels will be fed with the smaller gauge wire. But yeah, it's probably overkill anyway.

(You may also wonder why I don't simply go with the recommended 'Match PP-AC 13a + Match pp-iso 5' option. This is because I already have a ISO connector plugged at the bottom of my HU for a custom MMI screen.)

[Revoltos]

Are a set of bang olufsen mids worth it Bill?

[Billfitz]

The MWS 822 looks pretty good, but it won't fit in the underseat enclosure. The one they make that does fit, the CSB8w, is no better than stock.

I would imagine the B&O mids are fine, but again, buy them used. They're not worth what BMW charges for them new. For that matter no 4" speaker is. In the hi-fi/pro-sound world where I reside this is an 'as good as it gets' 4" speaker:

https://www.parts-express.com/Faital...4-Ohm-294-1120

You can pay more, but even the most golden eared audiophool wouldn't be able to hear any difference. If I did have the need to replace my midranges it would probably be with these. I'd have to do some mods to get them to fit, but that's not an issue for me.

[Revoltos]

Thanks for the advice Bill.
What is it about those Faitals that tickle your earbuds then? Notice they have a papercone too, I had it in mind that paper was a poorer material for the cones? Not going to lie, dont know why I thought that.
I guess the mods you would need are to do with the mounting hole pattern and physical electrical connections?

[Onizukachan]

Paper is the best material, but not weather resistant. It’s neutral sounding and doesn’t have the harshness of plastic cones. To me anyway. I loved the old rough paper cones on Jbl of the early aughts.

[Revoltos]

Ah ok. Fair enough. So paper is fine then. Cheers for the info Onizukachan. 👍

[Billfitz]

You can find $10 speakers with poly cones, $1k speakers with pulp cones. If you're concerned about moisture coat the back of the cones with this:

https://www.parts-express.com/Wet-Lo...oaAn0iEALw_wcB

What is it about those Faitals that tickle your earbuds then

This:

https://www.parts-express.com/pedocs...ifications.pdf

It's meaningless if you don't know how to interpret it, but if you're an acoustical engineer like myself it's the first thing you look at, the next being the price.

I guess the mods you would need are to do with the mounting hole pattern and physical electrical connections?

+1. Why BMW uses the bolt hole pattern it does defies logic.

[kierownik]

Originally Posted by Billfitz

.

What do you think of any of those woofers, please?
Any of them would be good with VIBE Powerbox65.4 amp?
https://www.ebay.co.uk/itm/234053994...EAAOSwDHxgyfjl
https://www.ebay.co.uk/itm/185262491...Cclp%3A2047675

[inigoale]

Apart from those 2, I have also seen these. I don't know if there will be much difference in sound between the 3. Which one is better? I have the vibe 65.4m amplifier installed
https://vibeaudio.co.uk/product/optisoundbmw8-v4

Originally Posted by kierownik

What do you think of any of those woofers, please?
Any of them would be good with VIBE Powerbox65.4 amp?
https://www.ebay.co.uk/itm/234053994...EAAOSwDHxgyfjl
https://www.ebay.co.uk/itm/185262491...Cclp%3A2047675

[Revoltos]

@Billfitz, So, following on from the bits and pieces that we spoke about on here, I got the opportunity to sit inside a mates 140i with full hardon kardon installation. I appreciate that this was on the HK amp but I can still say I didnt like the sound that much. Even across a few music genre's and at various sound levels and even playing with the equaliser, it just didnt produce a rich sound, its very high and "tinny".

So, after reading forums and reviews etc and ultimately arriving at the realisation that sound in a car is so variable. Car type, interior materials (leather interior cars have a completely different sound to other materials) kit used, music type etc.
Ive gone ahead with focal es100 k2 mids with seperate tweets to run with the match 7dsp amp. Still deciding on the rears. I do have a set of hk mids abd the front hk tweets so might stick those in for now as they will improve the sound over my base ones. Underseat subs, im still undecided.

Has anyone installed the K2's at all? Just wondering on the best way to put the tweeters in the hardon tweeter housing. Annoyingly, the k2 mids didnt come with foam rings. Can you get these from anywhere?

Thanks all.