Hey y’all!
I recently refoamed the speakers in my Blue Dalmatian iMac G3 because they were suffering from the infamous foam rot. I used this awesome tutorial as a reference: Replacing iMacG3 speakers suffering from foam-rot | Page 2 | MacRumors Forums, but I wanted to make a more detailed step by step guide based on my experience.
Parts / Tools
Replacement foam
US link: https://www.aliexpress.com/item/1005004702894828.html (I couldn’t verify whether it’s still available because I keep getting redirected to the German page.)
EU link: https://a.aliexpress.com/_EIs9jA2
Specifications (copied from the original MacRumors post):
• Product name: 1 inch speaker foam edge
• Material: Foam
• Outer diameter: 30 mm
• Ring outer diameter: 27 mm
• Ring inner diameter: 20 mm
• Inner diameter: 17 mm
• Remarks: Manual measurement; actual dimensions may vary by approximately ±2 mm.
Other things you’ll need
• PVA based or other suitable flexible glue
• Cotton swabs
• 99% isopropyl alcohol
• Phillips screwdriver
• A long, thin flathead screwdriver
• Something long and thin to use as a spacer, such as cotton swabs
Known good glues
• Dedicated speaker surround adhesive 🥇
• E6000 Plus (the “Plus” is important!)
• PVA based glue
The important thing is that the adhesive remains flexible after curing. Don’t use regular super glue.
Step 1: Disassemble the iMac
Remove the bottom housing, EMI shield, and HDD/drive cage to gain access to the speakers.
Step 2: Disconnect the speakers
Unplug both speakers from their cables.
Step 3: Remove the speaker pods, this part is tricky
Grab a sturdy, long flathead screwdriver.
There is a plastic retaining tab underneath the speaker pod, roughly in the middle. Carefully press this tab down with the screwdriver while simultaneously grabbing the speaker pod and sliding it toward the outside of the iMac.
Take your time and don’t force it. Make sure your screwdriver doesn’t touch any other parts.
Step 4: Open the speaker housing
You should now have the complete speaker pod in your hands.
Use a large Phillips screwdriver to remove the single screw at the bottom of the speaker housing.
Carefully separate the two halves. Try to leave as much of the original silicone/rubber seal intact as possible. You have to cut a small part of it later to free the cables, which isn’t a problem.
Step 5: Remove the speaker driver
Now you need to remove the actual speaker driver from its plastic housing.
First, free up the cable.
Then gently pull the speaker driver out. It’s held in place with a small amount of adhesive around its front edge.
Be careful not to pull on the membrane or the extremely thin wires attached to it.
Step 6: Remove the rotten foam
You should now have the bare speaker driver in your hands.
Use cotton swabs and 99% isopropyl alcohol to carefully remove the remains of the old foam from the accessible surfaces.
Try to remove all loose foam and old debris.
Also make sure there are no pieces of rotten foam trapped underneath the membrane or elsewhere around the driver.
Be careful with the voice coil, its former, and the tiny wires. Don’t soak them in isopropyl alcohol.
Step 7: Lift the membrane
This is another step where you need to be VERY careful.
Take a cotton swab or another long, thin object. Gently lift the membrane straight upward.
DO NOT force it.
Most importantly, be extremely careful with the two tiny wires connected to the membrane/voice coil assembly. They are very fragile and extremely difficult to repair if you break one.
Once you have enough space between the membrane and the bottom of the speaker, place one or preferably two cotton swabs underneath it as spacers.
The membrane/voice coil assembly should now remain raised while you work.
Step 8: Finish cleaning
With the membrane raised, use more cotton swabs and isopropyl alcohol to remove the remaining rotten foam and adhesive from the areas where the new surround will be attached.
Again, make sure there are no pieces of old foam underneath the membrane or near the magnet gap.
Keep debris out of the magnet gap!
Step 9: Install the new foam surround
Now it’s finally time to rebuild the speaker.
Apply a very thin layer of glue around the inner mounting surface of the membrane.
Take your new foam surround and carefully slide it over the top of the membrane.
Position it so that it sits as evenly as possible all the way around.
Don’t use too much glue. You only need a thin coating.
Step 10: Let the inner joint cure
Once you’re happy with the position of the new surround, leave it alone and let the glue cure.
I recommend waiting at least 24 hours. If you have the patience, 48-72 hours is even better, depending on the adhesive you’re using.
Leave your spacers/cotton swabs in place during this time.
Step 11: Glue the outer edge
Once the inner joint has cured, it’s time to attach the outer edge of the foam surround to the speaker frame.
Carefully remove your spacers.
Apply a thin layer of glue all the way around the plastic mounting ring.
Now gently lower the membrane and voice coil assembly back into its normal position.
Before committing to the final position, gently move the membrane up and down and make sure the voice coil moves freely.
You should NOT hear or feel any scratching or rubbing.
If you do, the voice coil isn’t properly centered in the magnet gap. Reposition the membrane until it moves freely.
Once everything is centered and moves without rubbing, gently press the outer edge of the foam onto the glue.
Make sure the surround is sitting evenly all the way around.
Hold it in position for a short while so it doesn’t lift back up.
You can then carefully turn the speaker upside down and place it membraneside down on a clean, flat surface. The weight of the speaker can help keep the surround in contact with the mounting surface while the glue cures.
Step 12: Let it cure again
Leave the speaker like this for at least 24 hours.
Again, 48-72 hours is even better if your adhesive requires a longer curing time.
Don’t play music through the speaker while the adhesive is still curing.
Step 13: Put the driver back into its little home
After all that waiting, your speaker driver is hopefully fully refoamed!
Now it’s time to put it back into its cozy little plastic home.
First, clean the mounting surface inside the speaker pod. Remove any remaining old adhesive, foam, or debris from the plastic ring where the front of the speaker driver sits.
Apply a small amount of suitable adhesive around this mounting surface.
Note: Glue is not absolutely necessary here, because the top shell holds the speaker driver in place anyway. I’m mentioning it for completeness.
Step 14: Reinstall the speaker driver
Place the speaker driver back into the housing, front/speaker side first.
Make sure the front of the driver makes even contact with the mounting surface all the way around.
Hold the entire housing frontside down so gravity keeps the driver against the adhesive.
Place it on a flat surface and allow the adhesive to cure.
Step 15: Route the cables
Once the speaker driver is securely glued back into the housing, route all the cables back into their original positions.
Reinstall the small plastic cable holder at the back of the housing.
Step 16: Close the speaker housing
Carefully reinstall the top half of the speaker housing and screw everything back together.
Make sure you don’t pinch any cables.
Step 17: Reinstall the speaker pods
Slide both speaker pods back into the iMac and reconnect their cables.
Step 18: Reassemble the iMac
Reinstall the drive cage, EMI shield, bottom housing, and everything else you removed.
Double check that you haven’t forgotten to reconnect anything.
Step 19: The moment of truth
Note: It’s best to wait 72 hours after gluing the outer edge of the foam to the speaker frame to make sure the glue is completely dry.
Cross your fingers and press the power button.
If you’re greeted by that beautiful BOOOONG without any crackling, buzzing, or scratching…
Congratulations!! You just successfully restored your original iMac G3 speakers!
Start with a low volume when testing them with music for the first time. If everything sounds clean, gradually increase the volume and enjoy your original speakers again.
One final warning
Be extremely careful with the tiny wires attached to the membrane/voice coil assembly. Don’t pull, twist, or put tension on them while the membrane is raised.
Also keep dirt, old foam, and glue out of the magnet gap. Even a tiny piece of debris in there can cause the voice coil to rub and make the speaker sound scratchy.
Final words
This tutorial is meant for the slot loading iMac G3s. I couldn’t verify whether the tray loaders use the same speakers, so maybe someone can confirm this.
It looks more difficult than it actually is, in my opinion. It’s definitely not for beginners, but if you take your time and be careful, there’s a very high chance you can do it.
If you have any questions, feel free to comment here!
Good luck! 🙂
I recently refoamed the speakers in my Blue Dalmatian iMac G3 because they were suffering from the infamous foam rot. I used this awesome tutorial as a reference: Replacing iMacG3 speakers suffering from foam-rot | Page 2 | MacRumors Forums, but I wanted to make a more detailed step by step guide based on my experience.
Parts / Tools
Replacement foam
US link: https://www.aliexpress.com/item/1005004702894828.html (I couldn’t verify whether it’s still available because I keep getting redirected to the German page.)
EU link: https://a.aliexpress.com/_EIs9jA2
Specifications (copied from the original MacRumors post):
• Product name: 1 inch speaker foam edge
• Material: Foam
• Outer diameter: 30 mm
• Ring outer diameter: 27 mm
• Ring inner diameter: 20 mm
• Inner diameter: 17 mm
• Remarks: Manual measurement; actual dimensions may vary by approximately ±2 mm.
Other things you’ll need
• PVA based or other suitable flexible glue
• Cotton swabs
• 99% isopropyl alcohol
• Phillips screwdriver
• A long, thin flathead screwdriver
• Something long and thin to use as a spacer, such as cotton swabs
Known good glues
• Dedicated speaker surround adhesive 🥇
• E6000 Plus (the “Plus” is important!)
• PVA based glue
The important thing is that the adhesive remains flexible after curing. Don’t use regular super glue.
Step 1: Disassemble the iMac
Remove the bottom housing, EMI shield, and HDD/drive cage to gain access to the speakers.
Step 2: Disconnect the speakers
Unplug both speakers from their cables.
Step 3: Remove the speaker pods, this part is tricky
Grab a sturdy, long flathead screwdriver.
There is a plastic retaining tab underneath the speaker pod, roughly in the middle. Carefully press this tab down with the screwdriver while simultaneously grabbing the speaker pod and sliding it toward the outside of the iMac.
Take your time and don’t force it. Make sure your screwdriver doesn’t touch any other parts.
Step 4: Open the speaker housing
You should now have the complete speaker pod in your hands.
Use a large Phillips screwdriver to remove the single screw at the bottom of the speaker housing.
Carefully separate the two halves. Try to leave as much of the original silicone/rubber seal intact as possible. You have to cut a small part of it later to free the cables, which isn’t a problem.
Step 5: Remove the speaker driver
Now you need to remove the actual speaker driver from its plastic housing.
First, free up the cable.
Then gently pull the speaker driver out. It’s held in place with a small amount of adhesive around its front edge.
Be careful not to pull on the membrane or the extremely thin wires attached to it.
Step 6: Remove the rotten foam
You should now have the bare speaker driver in your hands.
Use cotton swabs and 99% isopropyl alcohol to carefully remove the remains of the old foam from the accessible surfaces.
Try to remove all loose foam and old debris.
Also make sure there are no pieces of rotten foam trapped underneath the membrane or elsewhere around the driver.
Be careful with the voice coil, its former, and the tiny wires. Don’t soak them in isopropyl alcohol.
Step 7: Lift the membrane
This is another step where you need to be VERY careful.
Take a cotton swab or another long, thin object. Gently lift the membrane straight upward.
DO NOT force it.
Most importantly, be extremely careful with the two tiny wires connected to the membrane/voice coil assembly. They are very fragile and extremely difficult to repair if you break one.
Once you have enough space between the membrane and the bottom of the speaker, place one or preferably two cotton swabs underneath it as spacers.
The membrane/voice coil assembly should now remain raised while you work.
Step 8: Finish cleaning
With the membrane raised, use more cotton swabs and isopropyl alcohol to remove the remaining rotten foam and adhesive from the areas where the new surround will be attached.
Again, make sure there are no pieces of old foam underneath the membrane or near the magnet gap.
Keep debris out of the magnet gap!
Step 9: Install the new foam surround
Now it’s finally time to rebuild the speaker.
Apply a very thin layer of glue around the inner mounting surface of the membrane.
Take your new foam surround and carefully slide it over the top of the membrane.
Position it so that it sits as evenly as possible all the way around.
Don’t use too much glue. You only need a thin coating.
Step 10: Let the inner joint cure
Once you’re happy with the position of the new surround, leave it alone and let the glue cure.
I recommend waiting at least 24 hours. If you have the patience, 48-72 hours is even better, depending on the adhesive you’re using.
Leave your spacers/cotton swabs in place during this time.
Step 11: Glue the outer edge
Once the inner joint has cured, it’s time to attach the outer edge of the foam surround to the speaker frame.
Carefully remove your spacers.
Apply a thin layer of glue all the way around the plastic mounting ring.
Now gently lower the membrane and voice coil assembly back into its normal position.
Before committing to the final position, gently move the membrane up and down and make sure the voice coil moves freely.
You should NOT hear or feel any scratching or rubbing.
If you do, the voice coil isn’t properly centered in the magnet gap. Reposition the membrane until it moves freely.
Once everything is centered and moves without rubbing, gently press the outer edge of the foam onto the glue.
Make sure the surround is sitting evenly all the way around.
Hold it in position for a short while so it doesn’t lift back up.
You can then carefully turn the speaker upside down and place it membraneside down on a clean, flat surface. The weight of the speaker can help keep the surround in contact with the mounting surface while the glue cures.
Step 12: Let it cure again
Leave the speaker like this for at least 24 hours.
Again, 48-72 hours is even better if your adhesive requires a longer curing time.
Don’t play music through the speaker while the adhesive is still curing.
Step 13: Put the driver back into its little home
After all that waiting, your speaker driver is hopefully fully refoamed!
Now it’s time to put it back into its cozy little plastic home.
First, clean the mounting surface inside the speaker pod. Remove any remaining old adhesive, foam, or debris from the plastic ring where the front of the speaker driver sits.
Apply a small amount of suitable adhesive around this mounting surface.
Note: Glue is not absolutely necessary here, because the top shell holds the speaker driver in place anyway. I’m mentioning it for completeness.
Step 14: Reinstall the speaker driver
Place the speaker driver back into the housing, front/speaker side first.
Make sure the front of the driver makes even contact with the mounting surface all the way around.
Hold the entire housing frontside down so gravity keeps the driver against the adhesive.
Place it on a flat surface and allow the adhesive to cure.
Step 15: Route the cables
Once the speaker driver is securely glued back into the housing, route all the cables back into their original positions.
Reinstall the small plastic cable holder at the back of the housing.
Step 16: Close the speaker housing
Carefully reinstall the top half of the speaker housing and screw everything back together.
Make sure you don’t pinch any cables.
Step 17: Reinstall the speaker pods
Slide both speaker pods back into the iMac and reconnect their cables.
Step 18: Reassemble the iMac
Reinstall the drive cage, EMI shield, bottom housing, and everything else you removed.
Double check that you haven’t forgotten to reconnect anything.
Step 19: The moment of truth
Note: It’s best to wait 72 hours after gluing the outer edge of the foam to the speaker frame to make sure the glue is completely dry.
Cross your fingers and press the power button.
If you’re greeted by that beautiful BOOOONG without any crackling, buzzing, or scratching…
Congratulations!! You just successfully restored your original iMac G3 speakers!
Start with a low volume when testing them with music for the first time. If everything sounds clean, gradually increase the volume and enjoy your original speakers again.
One final warning
Be extremely careful with the tiny wires attached to the membrane/voice coil assembly. Don’t pull, twist, or put tension on them while the membrane is raised.
Also keep dirt, old foam, and glue out of the magnet gap. Even a tiny piece of debris in there can cause the voice coil to rub and make the speaker sound scratchy.
Final words
This tutorial is meant for the slot loading iMac G3s. I couldn’t verify whether the tray loaders use the same speakers, so maybe someone can confirm this.
It looks more difficult than it actually is, in my opinion. It’s definitely not for beginners, but if you take your time and be careful, there’s a very high chance you can do it.
If you have any questions, feel free to comment here!
Good luck! 🙂
