[hkm]

I'm in the process of upgrading the base system in my 2010 E92. I have already managed to mount the SWS-8 subs using the underseat enclosures and have run a four channel amp to run the subs and front door speakers. Details of that adventure here: http://www.e90post.com/forums/showthread.php?t=387129

I am now about to change the OEM 4" door speaker but my #1 goal was to maintain the OEM speaker grilles. For those of us with the E92 Coupe, this has been a big challenge. The E92 has even less clearance behind the door panel than the E90 so there's only a handful of speakers that are shallow enough to work--and many of them are not available in Hong Kong where i live. Fellow member Ksquare finally sourced me a set of Helix H234 components which are made in Germany and seem to have some reputation as decent entry-level performers. The cost for the set was about US$270. The mounting depth of the speakers is 48mm, so I knew it would likely be tight. The first 2 pictures show a comparison of the Helix 4" speakers and the OEM speakers.

Now that I had speakers, the next challenge was figuring out how to mount the Helix speakers. Due to the proprietary mounting points on the door panel, the Helix speaker could not simply bolt on. So instead I decided to try to create mounting adapter by sacrificing the original OEM speakers. As shown in the next 3 pictures, I ripped away the paper cone and then cut and grinded away the rest of the speaker and basket so that all that was left was the round speaker frame (I did clean it up with a dremel after taking this picture). What you will notice about the speaker frames is that they have a raised ring that extends about 5mm higher than the level of the mounting points. as a result, even though the speaker mounts are on the inside of the door panel, the speaker itself is about 5mm more forward and actually sticks through the hole in the door panel. My idea was to try and attach the new speakers ON TOP of this ring on the mounting adapter so that the speaker gain the benefit of this ring-height offset and sticks out through the hole just like the OEM speakers. Depth-wise, this method creates at least 5mm of additional rear clearance as compared to any mounting method that keeps the speakers on the back side of the door panel.

The top of the ring is 100mm in diameter, which is the same size as the outside diameter of the Helix speakers. As such, the speakers sat on the very top of the raised ring. To secure the speakers to the mounting adapter, I used a lot of silicone sealant (which also created a airproof seal between the speaker and mounting adapter). In pictures 7 & 8 the dark black parts are the original speaker frame, and the Helix speaker frame is sitting on top of it. You will notice that I had to remove the metal mounting tabs that came on the Helix speakers as those tabs would've prevented the OEM speaker grills from being reinstalled.

The last couple of pictures show the new speaker mounted in the panel. I did do a test and even though the speaker is protruding through the door panel, the OEM speaker grill can be reinstalled without interference.

As a final note, please keep in mind that my car is a post 3/09 build and the speakers used in both the doors and under the seats are different from earlier models. I have seen pictures of the pre 3/09 door speakers and while they are different, it appears that they could be used in a similar way as I have described here--but I haven't tried so I can't guarantee that it will work.

Onto the final project: modifying the tweeter sails so that the tweeters can point towards the windshield--as I've read a number of posts that say this will open up the soundstage.

[808MGuy]

Very nice. So is the new speaker frame sandwiched between the back of the door panel and the old speaker frame or is the only thing holding it against the old frame the silicone sealant?

[hkm]

Originally Posted by 808MGuy

Very nice. So is the new speaker frame sandwiched between the back of the door panel and the old speaker frame or is the only thing holding it against the old frame the silicone sealant?

The new speakers fit through the existing hole and sit a little forward of the door panel (but still behind the OEM grille)--which is why I gain at least 5mm in clearance on the backside. It is not mounted at all to the door panel. However it is secured quite well to the old speaker frame. Because the speaker is mounted on the front side of the old frame, the only way it can come out is to be lifted from the front of the frame. However, on the basket of the speaker there are a few tabs that I was able to bend over a lip on the back of the old frame so that it keeps the speaker from moving forward. I've attached a picture to show what I mean. The silicone also serves as an adhesive, but its primary function is to create a good seal between the frame and the speaker.

[808MGuy]

Originally Posted by hkm

The new speakers fit through the existing hole and sit a little forward of the door panel (but still behind the OEM grille)--which is why I gain at least 5mm in clearance on the backside. It is not mounted at all to the door panel. However it is secured quite well to the old speaker frame. Because the speaker is mounted on the front side of the old frame, the only way it can come out is to be lifted from the front of the frame. However, on the basket of the speaker there are a few tabs that I was able to bend over a lip on the back of the old frame so that it keeps the speaker from moving forward. I've attached a picture to show what I mean. The silicone also serves as an adhesive, but its primary function is to create a good seal between the frame and the speaker.

Nice job.

[ken530i]

Originally Posted by hkm

Fellow member Ksquare finally sourced me a set of Helix H234 components which are made in Germany and seem to have some reputation as decent entry-level performers. The cost for the set was about US$270.

How do you like the Helix 234? Are you pleased? What would you do to improve sound quality?

Thks

Ken

[hkm]

Originally Posted by ken530i

How do you like the Helix 234? Are you pleased? What would you do to improve sound quality?

Thks

Ken

For the price, and given the limited options available in Hong Kong, I am pleased. A couple of notes:

1) the tweeter is too large to snap into the OEM housing. However, you may wish to play with the direction before mounting the tweeter anyway. I modified the housing to change the direction of the tweeters so that they face away from me and more towards the windshield. I then used silicone caulk to hold the tweeter in place.

2) I did use silicone caulk to seal the mid-speaker to the front of the speaker mount that I created.

3) finally, the frequency range of the speakers on the low side is 90 hz. Not particularly low so I'm probably weak in the mid-bass area but I don't really notice it. For discriminating listeners however, this may be a concern.

[VP Electricity]

That's a trick some guys use in the Lexus too. I am concerned that at high excursions, that mounting method might allow the surround to hit the back of the grille. I've had this problem in X5 E70 and in 1-series. It may sound like a tweeter distortion. Keep an ear out for it.

I am currently running H234 in my car as a test. I have the tweeters on axis and it works well for me. Watch how they sound after break in, as that tweeter does smooth out a lot after a few hours of playing.

They are bigger than the OEM, definitely. Are you using the passive crossovers? Which output setting are you using?

[hkm]

Originally Posted by VP Electricity

That's a trick some guys use in the Lexus too. I am concerned that at high excursions, that mounting method might allow the surround to hit the back of the grille. I've had this problem in X5 E70 and in 1-series. It may sound like a tweeter distortion. Keep an ear out for it.

I am currently running H234 in my car as a test. I have the tweeters on axis and it works well for me. Watch how they sound after break in, as that tweeter does smooth out a lot after a few hours of playing.

They are bigger than the OEM, definitely. Are you using the passive crossovers? Which output setting are you using?

I agree that the surround is pretty close to the grille. I did just try running the volume at an uncomfortably high level and did not pick-up this sort of distortion--sound remained quite clean.

Funny you should mention the break in as I commented not 30 minutes ago that I feel like the speakers sound better after running them for a week.

I wish I had done some testing to decide whether I like on-axis or off before mounting the tweeters. When I move my head so that they get on-axis, I prefer the sound--but this could just be the ear's natural preference for higher volume.... At this point, I feel like I put so much effort into modifying the housings and securing the tweeters in an unnatural position within the housing that the idea of undoing it all makes me a bit ill. But if you actually do any testing on-axis vs. off-axis and conclude it sounds better on, I will probably rip it apart and make the change.

I am running the passive crossover that was included and was able to fit it in the door panel on the flat spot a little below the speakers by removing the housings and just mounting the circuit board. I did not change any of the default (flat) jumper settings as frankly by that point I just wanted to get the install done--and right now I don't want to keep pulling the door panel off again if I can avoid it. But having spent time with the system I don't feel like I really want to adjust the tweeter level.

I look forward to hearing your views on these speakers. BTW do you have the H234 or P234? I checked with Helix and they said that the differences between the two are in the membrane and magnet. In Hong Kong it was about a US$70 difference between the two sets. No having heard them side-by-side I cannot comment on the difference but note that the P234 claims a low end of 85hz versus the 90hz of the H234.

[VP Electricity]

That sort of specification isnt' too useful - the manufacturers usually don't specify how many dB down the speaker is at 90 or 85 (called the "deviation"). Without specified deviation, freq response specs aren't helpful.

I have not heard of a 100mm speaker that can play down to 85 with 3dB or less deviation.

That said, how low are you playing them with your system crossover? To the factory setting on the xover or...

My xover doesn't have jumpers for tweeter output, it has jumpers for 2-ohm woofer output if I'm using dual woofers. The tweeter output is selected by the screw terminal used for the tweeter's positive wire ("0", "+1", "+3", "+6").

[VP Electricity]

To speak to your other request, I really like the speakers, especially the tweeters, but they were too loud at first. I'm running them active, using a Zapco DC650, and I had to cut the Helix -2dB more than the Morels. This makes sense as their impedance is lower (the morel MT-23 is around 6 ohms and the Helix is around 4, with a DCR of 3.2 or so).

So I really like them, but I can't say how they sound with the passive. Next step is adding the passive and seeing how they do.

BTW, my DSP EQ is all turned off while evaluating these.

[hkm]

Originally Posted by VP Electricity

That sort of specification isnt' too useful - the manufacturers usually don't specify how many dB down the speaker is at 90 or 85 (called the "deviation"). Without specified deviation, freq response specs aren't helpful.

I have not heard of a 100mm speaker that can play down to 85 with 3dB or less deviation.

That said, how low are you playing them with your system crossover? To the factory setting on the xover or...

My xover doesn't have jumpers for tweeter output, it has jumpers for 2-ohm woofer output if I'm using dual woofers. The tweeter output is selected by the screw terminal used for the tweeter's positive wire ("0", "+1", "+3", "+6").

I'm running the set on the front channels of my amp with the high-pass on the amp set a little below 90 (effectively full-range for these speakers). That signal goes to the passive crossover, which interestingly seems different from yours. My cross has a -3/0/+3 dB tweeter level adjustment that is set with a repositionable gold plated jumper (looking at my instruction manual now). I've left that jumper at the "0" setting. The crossover also had a switch or jumper for 4 ohm / 2 ohm settings.

[VP Electricity]

My kit is older - it has a black top instead of the clear panel on the xover.

I would quibble, in that running them "full range" would result in over excursion - but it is encouraging to hear they don't bottom out running to 90 with a 12dB filter!

[starbai]

thanks for this!

I'm having a hell of a time that will work in the doors of my e90 while keeping the stock look.

Everything that 'used to work' is either discontinued now or totally out of my budget.

I wanted to go with the Helix but with your detailed post, now I know that I can handle the work and the look i'm going for will be possible.

Thanks again!