Replacing Speaker Surrounds

Introduction

I have a pair of much loved AVI Bigga-Tron's (I had some more loved Nu Neutron II's that perished in storage... let us take a moment for their passing [ ... ]) that I have turned into active smart speakers through the wonder that is the Ikea Symfonisk Bookshelf Speaker - and all the options they open up. The foam (as opposed to rubber) surround on them has been on life support for an extended period - and I have been waiting for a failure to happen.

Why Replace Speaker Surrounds

Primarily because when they fail, the speaker ceases to speak. Sad times.

There is no air seal around the driver. The voice coil will no longer be centred. Sealed enclosures will no longer be sealed - and now feature air rushing in and out through the torn foam.

I am guessing exposure to UV light is the main issue - and yes, these puppies have spent the majority of their lives with the covers off with the sun arcing across them daily. Less negligence - more wear and tear.

The foam stiffens over time, and while that can be kept alive a little with application of silicon oil, it's not ideal. Sure it is a great short-term solution - but it stains, could damage the driver itself, and it tends to pool at the bottom of the surround after any time at all.

What Needs To be Done?

Simple enough (he said through gritted teeth):

• Remove the existing foam from the basket.
• Remove the existing foam from the driver.
• Glue the new foam to the driver.
• Centre the driver and glue the foam to the basket.

The glue is a PVA type adhesive (Polyvinyl Acetate - the white, Paper or Wood Glue - I think NA refer to it as Elmer's Glue). It can be brushed on with a paintbrush and smoothed with a finger safely. Water washable. Peels off non-adsorbent surfaces.

Sure - right - so the driver - it's made of something sturdy, right? Wrong. It is doped paper. Lovely. Delicate++

How It Went

At first inspection - taking out the new foams, they looked crazy small - but then offering them up, it was apparent - no - these were the right ones.

It takes a moment of bravery to start something that could essentially END the speakers - but a start would have to happen now or later when they failed. F*@# IT - let's do this. I took some scissors and snipped into the foam and then around.

Having checked with the vendor, these were the correct surrounds for these Vifa C17WG-69-08 (the same driver is used in the Dali 104)drivers. - nonetheless - that moment when you realise that there was a BIG difference between the surrounds in situ and the ones that I was going to be replacing them with. These were thin and almost crisp as I tore away- more brittle fabric than foam.

I peeled away what I could without tools and made a small pile of remnants. I salute you for many, many happy hours of service.

At this point, the driver is free to live their own life and has a fair amount of play in it - but almost entirely held centred by the spider at the base of the basket. This was a HUGE worry for me - but one that it would appear was going to be 'close enough for jazz' as long as I didn't make any dumb mistakes. Me. Hah! Master of such things.

I used a screwdriver to scrape away the remnants on the edge of the basket - which you would think would be super stressful - screwdriver, around a speaker cone - with force - but no - at this point, its all in :D

I removed the remaining foam from the back of the speakers with a scalpel. I hasten to add - not digging in - but running across the surface - this was a doped paper driver - its a bold moon - but I am not a maniac.

The surround on this Vifa driver was front mounted on the basket rim and sat behind the driver cone. This was how I envisaged things going back.
Seating the surround on the basket, it was immediately apparent that to put this back in the same configuration would mean that driver would be pulled proud. This was not ideal.

After taking a moment to realise that if I attached it to the front, then this was not an issue and that the slightly ragged edge would be hidden - I got over myself and pressed on.

I applied a THIN layer of the provided glue to the underside of the foam and allowed it to dry. I then used an equally thin layer to the driver and pressed the two together.

Panic sets in as it starts to decide that "the whole glue thing is not for them" in places - but an occasional revisit and pressing around the circumference made good. These were point-pressed - working your way around looked like it was going to set up a stretch and push a bubble of slack ahead of me... so nope. Pinches were just fine, working my way around on opposite sides.

Allowing to dry overnight, the stress starts to die off, thank god - in a what is done is done way, even if you have just executed one of your favourite monitors.

Now applying the glue to the basket surround - a quick depression of the driver as centrally as possible gives you an idea of where this should be sitting - free of any driver coil issues. Again the pinching process. Repeat. Repeat. Dry. Repeat. Dry.

Victory is ours!

Firing it up and we have a winner.

It does sound different given that you have the other driver to compare against; it's slightly less of an opinion and more verifiable.

Repeat for the second speaker.

TruPlay.

Winning.

Why did I not do this earlier - can I introduce you to - the grey hairs you gained.

What Went Badly

Removing the foam from the back of the drivers. It was "stuck", and being brittle meant that it did not want to peeled off.

Use less glue than you think. Pre-coat the foam seemed to help me - but pressing spreads things out hugely.

Learning as I went. Something to practice on first would have been time well worth spending.

Want Went Well

The second speaker looks a lot better.

All of it all in all, to be fair.

It sounds far tighter, and I know that short of a puncturing event - these are going to be good companions for an even longer time with a new lease of life.

Would you do it again

Yes.

If I had known it was an option and had the confidence to do it earlier - I would / should have done so.

If you have a favourite pair of monitors in good condition that sound familiar - but they are getting tired - do them ... do yourself... a favour, and find a company that can help you with the right surrounds and go from there.