Hi guys,
I've realized some time ago that my speakers are reaching 15 years of trusted usage.
I knew that in the crossover board inside the speaker there was some non polarized electrolytic capacitors.
I decided to refresh them all, and while doing so, trying to upgrade some to film caps where the physical size permits.
Here is how it looks originally.
And view of the crossover:
Removing the board is easy. I removed both woofers, disconnect the wires, removes all the nuts and the 4 at the posts.
The board looks like this.
As you can see there are 5 electrolytic caps and 2 film caps.
After measuring them all, I decided to replace all the electrolytic caps. 3 could be replaced with film caps, and 2 had to remain electrolytic as film caps would be way to big.
Here is what I had to work with:
I had to make 3 lead holes to accommodate larger lead spacing of the red film caps, but that's it.
I used clear Goop to glue the caps as original and here is how it looks after the upgrade.
I had to be careful for the big cap not to extrude too much from the board as space is tied in the speaker.
Unfortunately, the big cap was covering a stud so I had to remove it. I remove the back plate and cut it. I could have cut it inside the speaker but didn't want to damage the mid and tweeter with the Dremmel vibration, left alone the metal parts and sparks.
There is still 9 attachment points so that more than enough. These speakers are extremely well build and sound.
Put back all together, no issue there. Here is a view before closing it.
The red caps are coupling caps for the mids and highs. So I especially wanted to go film there. The remaining electrolytic caps are filters for the bass, less important to me.
The sonic improvement is drastic. The speakers are much more detailed and fast. It's really a big jump in sound reproduction, at relatively low investment.
I recommend to all LS340 owners out there this upgrade.
I hope it helps,
Brice.
I've realized some time ago that my speakers are reaching 15 years of trusted usage.
I knew that in the crossover board inside the speaker there was some non polarized electrolytic capacitors.
I decided to refresh them all, and while doing so, trying to upgrade some to film caps where the physical size permits.
Here is how it looks originally.
And view of the crossover:
Removing the board is easy. I removed both woofers, disconnect the wires, removes all the nuts and the 4 at the posts.
The board looks like this.
As you can see there are 5 electrolytic caps and 2 film caps.
After measuring them all, I decided to replace all the electrolytic caps. 3 could be replaced with film caps, and 2 had to remain electrolytic as film caps would be way to big.
Here is what I had to work with:
I had to make 3 lead holes to accommodate larger lead spacing of the red film caps, but that's it.
I used clear Goop to glue the caps as original and here is how it looks after the upgrade.
I had to be careful for the big cap not to extrude too much from the board as space is tied in the speaker.
Unfortunately, the big cap was covering a stud so I had to remove it. I remove the back plate and cut it. I could have cut it inside the speaker but didn't want to damage the mid and tweeter with the Dremmel vibration, left alone the metal parts and sparks.
There is still 9 attachment points so that more than enough. These speakers are extremely well build and sound.
Put back all together, no issue there. Here is a view before closing it.
The red caps are coupling caps for the mids and highs. So I especially wanted to go film there. The remaining electrolytic caps are filters for the bass, less important to me.
The sonic improvement is drastic. The speakers are much more detailed and fast. It's really a big jump in sound reproduction, at relatively low investment.
I recommend to all LS340 owners out there this upgrade.
I hope it helps,
Brice.
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