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Easy DIY Improvement of Audio for a Few Dollars

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I installed Light Harmonic upgrade over my standard audio on Saturday. It is clear improvement to the cheap lightweight speakers, but you can only go so far by replacing the elements. The door card and attachments are clearly not too well designed and resonate even on moderate sound levels so much that it causes easily audible distortion (a second culprit was found, though). As comparison, my year '00 Audi A8 door cards do not resonate on touch at all (and I mean nada) before reaching distortion levels from the Bose head unit. That is a design released in '94... Bass is nice and firm without subwoofer for my needs, which is rock music.

I saw this video today and got inspired (starting 1:40)
1st finding: speaker grille pops out easily. 2nd finding: they had added some cellular plastic around speaker bodies, and I thought that might be worth trying. Oh yes it was!

I had some Armaflex (19mm) cell rubber insulation lying around, and I cut 2 inch wide strips, which I tucked in the gap between front speakers and door. I used same interior vinyl tools for tucking as with the door card removal. Be careful when doing this, as it would be very easy to make a dent in the speaker cone, as you'll need to apply force. I left upper part without armaflex, as it seemed risky to tuck it blindly behind the door card. If I'd remove the door card, it would be easy to do around the whole speaker (I'd use glue)..

I also applied Stp Black Gold (aluminium laminated butyl) on all surfaces, including inside of grille smooth parts and inside of door card, for the small area accessible through the grille. I had already put this on the metal parts of door (but not on the door card) while doing the LH upgrade.

One of the major culprits of the boomy, resonating bass was found: there is a bass port hole behind the grille! I tucked these full of armaflex. In fact there was already a small piece of some kind of softening material in rear port holes. If you do nothing else, try at least this! It can be done and undone in 5 minutes. You can see the hole open in the video, and tucked in my photo.

20170918_202054 (1).jpg


For rear speakers, there is no gap visible through the grille, so covering around them would be needed to be done when the card is removed. Since I just did the LH upgrade on 2 days ago, didn't have the motivation right now (plus it is night time over here). Port hole armaflex and Stp treatment did some good though.

All this really made a difference to the firmness of the bass and lower mid range. Resonation is less and bass distortion from the porthole is less evident. The sound is no longer tiresome, especially after toning down upper bass with EQ (a DSP would really do the trick here). Now I'd say it has been upgraded from standard audio poor level, and LH acceptable level to ok/good level. I can now listen on level 6 or 7 without annoyance, before it was 3 or 4).

For how easy this was, and for estimated cost of 5 euros for material, the improvement is even better value than LH upgrade, which cost about 1k€, no doubt. Same trick could be tried for the UHFS or standard audio as well with what I expect would be an improvement in each case. I think they should supply this stuff and instruction with the LH kit!
 
I have standard audio and stock Tesla speakers all around. Looking for small improvements in anything for cheap is fun.

All I can find locally is armaflex 1/2" pipe wrap foam lengths with self-adhesive strip, which I happen to have some at home.
Same material? I could cut this lengthways to make strips.

Instead of tucking around speaker/door gap, why not pull speaker out, make a gasket and put speaker back on... would that be better?

Did you literally plug the front port hole full of material so no air passes through? Are you saying stock Tesla speakers should not be ported design in the first place?

..thanks
 
I have standard audio and stock Tesla speakers all around. Looking for small improvements in anything for cheap is fun.

All I can find locally is armaflex 1/2" pipe wrap foam lengths with self-adhesive strip, which I happen to have some at home.
Same material? I could cut this lengthways to make strips.

Instead of tucking around speaker/door gap, why not pull speaker out, make a gasket and put speaker back on... would that be better?

Did you literally plug the front port hole full of material so no air passes through? Are you saying stock Tesla speakers should not be ported design in the first place?

..thanks
A "cheap" upgrade would be the front door speakers from the premium system. You need the two speakers and the mounting rings (with the screws). It's a bolt in swap and the speakers plug right it with no modifications needed.
 
I have standard audio and stock Tesla speakers all around. Looking for small improvements in anything for cheap is fun.

All I can find locally is armaflex 1/2" pipe wrap foam lengths with self-adhesive strip, which I happen to have some at home.
Same material? I could cut this lengthways to make strips.

Instead of tucking around speaker/door gap, why not pull speaker out, make a gasket and put speaker back on... would that be better?

Did you literally plug the front port hole full of material so no air passes through? Are you saying stock Tesla speakers should not be ported design in the first place?

..thanks

Don't use armaflex with self adhesive if you want to tuck it in, I'm sure it won't go. Or maybe you can leave the adhesive strip on...

Sure pulling speaker out is better option, but that requires door panel removal. Upper torxes are behind upholstery. Tucking you can do by just popping out the grille.

I'd like to hear someone try this with standard and UHFS audio. With LH upgrade it made a positive difference. Surely the bass is also a matter of subjective taste, but I do not like distortion, which ports do create by default. And this is not a high end port design.
 
Don't use armaflex with self adhesive if you want to tuck it in, I'm sure it won't go. Or maybe you can leave the adhesive strip on...

Sure pulling speaker out is better option, but that requires door panel removal. Upper torxes are behind upholstery. Tucking you can do by just popping out the grille.

I'd like to hear someone try this with standard and UHFS audio. With LH upgrade it made a positive difference. Surely the bass is also a matter of subjective taste, but I do not like distortion, which ports do create by default. And this is not a high end port design.

Has anybody done just a port-plugging to compare the sound of standard grade speakers?
 
Here are the step by step instructions with pictures.

All you need is:
- a piece of insulating material. Armaflex or similar seems to work well. Any rubber cell mat would probably work. Thickness used was 19mm (0,75 inch), and that was just about right to fit firmly.
- vinyl interior prying tool. Or any flat stick :)
- optional: noise dampener material which you can stick on plastic surfaces (e.g. silent coat). I recommend something that is easy to shape and even peels off cleanly if necessary (Stp Black Gold was great). Amount used was about a square foot.

Picture of 120mm diameter pipe armaflex piece used below. You'll need to cut away about 1/3 in order to do it safely through the grille hole, but you can do it as you are already installing the stuff, so no exact measurement is needed.

20170919_191109.jpg


Step 1:

In the front: Remove speaker grille. It comes off when you pull firmly and directly away from door. Do not twist. Clips are metal, so they can take it. You'll need two hands and a firm pull at both ends.
20170919_174703.jpg


Step 2:

Start tucking the insulating material in the gap around the speaker. If the material is same thickness I have used, it will be tight. You can assist with a tool, as here I am doing with a vinyl interior clip prying tool. This needs patience and care because it would be easy to damage the speaker cone or cone surround rubber.

20170919_175023.jpg


Step 3:

Cut a suitable size piece from insulating material to be inserted into the port hole. You can also test other materials or for right amount of stuff for your preference. You'll find that you can add EQ for the bass, and you'll get same level of bass as before, but much less resonance / distortion.

20170919_175120.jpg


Step 4 (optional):

Coat the backside of grille, and door plastic in front of speaker with dampener. Avoid coating the clips so it fits right back in.

20170919_175140.jpg


Step 5:

Repeat on the other side. In the back, there is no room for the around speaker insulation through the grille hole, but bass port hole should be dampened nevertheless.

You're done!

It is a fast tweak and can be undone easily. Let me know how you like the improvement?

Personally, spent today a little more time listening, and once I found good EQ settings (add bass, tone down lower mid-range, leave higher frequencies to 0, moved "fader" quite a lot forward), I have to say I am really happy with the result! I'm sure the LH speaker spiders are still breaking in as well, and improving the effect.
 
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I have made the simple mods above (filled port holes and around front speakers with foam and sound deadening alubutyl on the plastic and it really has made a terrific difference. Standard audio system improved by at least 30% I would say - mainly in deep bass clarity and lack of distortion/resonance. Mid range still a bit flabby, but this can be toned down with EQ (+4,-2, -0.5,0,0)
 
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@Cooker Thanks for confirming I'm not the only one who hears the difference, and that it improves standard audio as well!

@pkodali I don't know, but after watching Light Harmonics installation video from Youtube, it sure looks the Model X has same speakers and same design in doors. Anyone with Model X could try if you can get the grilles off the door and post a picture? It looked like there is a port hole as well which could be stuffed for easy improvement, at least.

@xenodata Yes, I used a product called StP Black Gold, similar to Dynamat. If I'd do it again, I'd apply the same stuff also on the door card, under the existing fluffy stuff, not only on the sheet metal on the door. It is a bit more work as you'd definitely need to get all the wiring clips detached.

It is a shame the video in the 1st post has been taken offline. It was about a >20k$ custom Model S audio installation, and this same trick has been applied there.

I have done also further steps to improve audio, but these are no longer for a few dollars.
 
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@Cooker Thanks for confirming I'm not the only one who hears the difference, and that it improves standard audio as well!

@pkodali I don't know, but after watching Light Harmonics installation video from Youtube, it sure looks the Model X has same speakers and same design in doors. Anyone with Model X could try if you can get the grilles off the door and post a picture? It looked like there is a port hole as well which could be stuffed for easy improvement, at least.

@xenodata Yes, I used a product called StP Black Gold, similar to Dynamat. If I'd do it again, I'd apply the same stuff also on the door card, under the existing fluffy stuff, not only on the sheet metal on the door. It is a bit more work as you'd definitely need to get all the wiring clips detached.

It is a shame the video in the 1st post has been taken offline. It was about a >20k$ custom Model S audio installation, and this same trick has been applied there.

I have done also further steps to improve audio, but these are no longer for a few dollars.
Now the alubutyl has hardened its even better. It’s not a minor difference. I haven’t even deadened the rear yet, and only did the speaker grilles. Right now, I’m tempted to deaden every available surface on the car! I wonder if anybody has used this stuff to reduce road noise? Would it do you think, if you, say, coated the floors...
 
Now the alubutyl has hardened its even better. It’s not a minor difference. I haven’t even deadened the rear yet, and only did the speaker grilles. Right now, I’m tempted to deaden every available surface on the car! I wonder if anybody has used this stuff to reduce road noise? Would it do you think, if you, say, coated the floors...
Reminds me of working with classic cars in another life.......
 
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Wow, huge thanks for discovering and sharing this. I can personally verify that just by stuffing the bass ports (I used some extra packaging foam I had lying around) it made a very noticeable improvement. Also while the rear door speakers did have some noise absorbing material already in there as you mentioned, it was just a small amount (not enough to fill the port) so I was able to add quite a bit more to fully pack it in there.

I now find that with the lowest two bands on the equalizer maxed-out, the bass overall sounds MUCH better and clearer at high volumes. I was very strongly considering getting speaker upgrades in large part due to the muddiness at high volumes with the stock speakers, but this might be enough improvement to make such an upgrade unnecessary.
 
So I performed "part 2" on one of my front door speakers by filling in the gaps around the speaker with acoustic rubber/foam. However, as opposed to filling in the bass ports (which made for a SIGNIFICANT improvement), I actually found that it sounded worse after filling the area around the speakers. So I would definitely recommend trying it out on one speaker first before doing both front speakers (using the equalizer and moving the "+" from side to side makes it really easy to isolate a specific speaker and compare them).

EDIT: I should probably add that this is my experience with the stock speakers; with upgraded door speakers I can certainly see how it would be beneficial.
 
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So I finally installed 2 Light Harmonics speakers in the front doors of my 01/2018 Model S today. At first test with the door panels still off, I didn't think there was a huge difference.

But once I got everything put back together and listened to a few different songs I began to notice the music was much richer than before. My car came with standard audio, so adding the LH speakers didn't suddenly add subwoofer capability, but it made the music more rich across the spectrum and the bass was more noticeable. Even with the EQ all set to 0's, which I think I prefer over other settings.

The LH speakers now come with a gasket on the back of them and the mounting holes lined up perfectly with the speaker holes in the front doors of my car. I was able to order only the front two speakers from Light Harmonics and I think the improvement in sound was good over factory. I'm doubtful the sound would have been much improved again by adding the LH speakers in the rear doors. The two speakers were $500 + $68 shipping.

On the 01/2018 Model S, I didn't see any holes in the door that I had to plug up to remove any resonance/hollow sounds. I didn't add sound deadening material/dynamat but I might in the future if I want to try and improve it further.
 
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So I finally installed 2 Light Harmonics speakers in the front doors of my 01/2018 Model S today. At first test with the door panels still off, I didn't think there was a huge difference.

But once I got everything put back together and listened to a few different songs I began to notice the music was much richer than before. My car came with standard audio, so adding the LH speakers didn't suddenly add subwoofer capability, but it made the music more rich across the spectrum and the bass was more noticeable. Even with the EQ all set to 0's, which I think I prefer over other settings.

The LH speakers now come with a gasket on the back of them and the mounting holes lined up perfectly with the speaker holes in the front doors of my car. I was able to order only the front two speakers from Light Harmonics and I think the improvement in sound was good over factory. I'm doubtful the sound would have been much improved again by adding the LH speakers in the rear doors. The two speakers were $500 + $68 shipping.

On the 01/2018 Model S, I didn't see any holes in the door that I had to plug up to remove any resonance/hollow sounds. I didn't add sound deadening material/dynamat but I might in the future if I want to try and improve it further.
@xenodata I fully agree that replacing only front speakers gives almost all benefit because rear speaker sound is anyway limited at the source. Almost no bass is played through the rear. You can expect the LH speakers will get slightly better after breaking in for a month of use or so. More benefit can be gained by installing better amplifiers (with DSP).

What do you mean by the gasket behind the speakers? I would really appreciate a picture.

Did you remove the speaker grilles? Mentioned bass port hole is under the grille (visible on some of the pics above). Door redesign would be major news. Since LH speakers still fit in, redesign sounds unlikely.
 
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@jcdenton40 What material did you use to stuff around the speaker? The material has to be something which dampens any resonation to door card.

Each of the cheap tricks (dampen port hole, around the speaker, apply alybutyl as extra mass to door) are aimed to do one thing: isolate passing of sound waves to surrounding structures and causing audible resonation.
 
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"What material did you use to stuff around the speaker? The material has to be something which dampens any resonation to door card."

I used this, cut it into about 3-inch wide rectangles, and stuffed them around the speaker and filled in most of the gaps. Basically I found that it did exactly what was intended, i.e. eliminated almost all of the resonance, but IMO it was too much and it sounded better with at least some resonance. So I took most of it out and left just a few strips in there and it sounds great.

https://www.amazon.com/gp/product/B01KAD1XES/