Manufacturing and mounting of surrounds for the woofers and mids

(Woofer’s use frequency from 20Hz to 500Hz, mid’s use frequency from 500Hz to 2,5KHz)

When I got these speakers back, one set of woofer and mid was intact from any intervention while the other one hab been tinkled: some strange foams where glued on the diaphragms. This repair was horrible and almost non-working. Besides, the aceton based glue used to mount the foams made much damages on the diaphragms which had to be restored before to apply some new surrounds. See the diaphragms repair section.

To manufacture some new surrounds, I was going to apply my known fabric pressing method. With my experience, I quickly decided which fabric to use along with which other materials. But I had the choice between two solutions for the repair:

  1. -1/ To press one piece square surrounds

  2. -2/ To press several surrounds pieces which would then be assembled together in the angles.

After a few trials, The solution number 2 was obvious. Indeed the solution number 1 did not have a satisfying behavior in the angles. Therefor, I’ve made 8 surrounds per diaphragm which were then glued together with butyl rubber and coated with my usual viscoelastic/impermeable treatment.


1st loudspeaker, tinkled by a previous protagonist.

2nd loudspeaker in its original state, the tweeter set being dismounted.

Close-up on the inappropriate foams and the damaged diaphragms.

Close-up of the original untouched foams.

Mid 2 before cleaning.

Mid 2 after cleaning

The diaphragms is ready for the mounting of the new surrounds.

Mid 1 before restoration.

Mid 1 after restoration.

The diaphragms is ready for the mounting of the new surrounds.

Surrounds for the woofer, after pressing.

Surrounds for the woofer, after cutting at length.

Protection of the mid’s diaphragm while mounting the surrounds.

After mounting of the surrounds parts, the angles are glued together with butyl rubber.

Woofer’s surrounds after bonding on the diaphragm.

Woofer’s surrounds with one layer of viscoelastic treatment drying.

ProjectsProject S-F1 customSurounds repair

Pioneer S-F1

Surrounds for the woofers and mids

Loudspeaker 1 after complete restoration. (This one comes from far away...)

Loudspeaker 2 after complete restoration.

Comparison of the 2 woofers. Less than 1Hz of difference on the Fs.

Comparison of the 2 mids. Less than 10Hz of difference on the Fs.