Loudspeakers101

Tuesday, 5 June 2018

Coral 8A in custom bass reflex enclosure

Coral 8A speakers in big bookshelf design

I made them a couple of years back during a short holiday to venture in to the world of full range sound. My priority was to build a simple and not too bulky box in the shortest possible time hence i opted for this big bookshelf bass reflex design. The Corals have wooden phase plugs installed months ago without a proper enclosure until now. Building the box was relatively fast and easy but the finishing works was a bit of a nightmare due to my decision to use natural oak veneers for the finishing. It was painstaking to match the grains and join the seems carefully piece by piece, sanding and apply clear coatings. The end results was quite satisfying when they finally made to my living rooms where they start to sing loud and clear, The only shortcoming however, if i must say, it was the bass department that didn't really justify given the size of the driver (8"), i think it could have been much better if they were housed in proper horn loaded cabinets.

Adding Phase plus to Coral 8A

Adding custom made wooden phase plug to Coral 8A driver

Friday, 6 February 2015

Mission 752 speaker

Type: 2 way, 2 driver loudspeaker system
Frequency Response: 40Hz to 20kHz
Recommended Amplifier: 35 to 150W
Impedance: 8Ω
Sensitivity: 90dB
Bass: 1 x 170mm Aerogel paper
Tweeter: 1 x 26mm ferrofluid cooled
Enclosure: 28 litre, bass reflex
Finish: real Rosewood veneer
Dimensions: 875 x 198 x 255mm
Weight: 18.5kg

Made in England

Mission 752 in gorgeous Rosewood veneer

Typical British speaker signature sound with edequate amount of bass.

Very easy to listen to, slightly hot on the extreme highs but acceptable.

Very well built cabinet, looks expensive!

JBL L200 Studio Master Speaker Cabinet Rebuid

JBL L200 studio master cabinet rebuild

The process of rebuilding the JBL L200 enclosure for a friend...

It was supposed to be a direct replacement for the old damaged cabinets in the initial plan but end up the speakers being upgraded with new set of crossovers and super tweeters. The design of the box and driver configurations had also gone wild with "out-of-the-box" head for the tweeter and super tweeters sitting on a separate woofer chamber at the bottom. The materials for the bass boxes were made of 20mm thick plywood with heavy internal bracing, exterior finishing was done in real walnut wood veneer. The "head" was made from solid hardwood block unattached to the main box for easy positioning and allow time-alignment setting with the lower frequencies.

The speakers had been returned to the owner as soon as they were completed. I didn't have long enough time to listen to them to comment about the sound quality. However I am sure the end product will become a conversational piece though.

Preparing to cut the 5/8" thick plywood

Cut to size

Internal bracing are added for extra strength

Start putting them together

More bracing

Cutting the hole for the 15" woofers

Installing the PVC port

Speaker baffle

Putting them together

Nice fit!

Back side with the binding post terminal opening

Base cabinet taking shape

Ready for veneering

Veneer

More veneers

Carpentry works done! next is the finishing job.

Dear readers, it was very unfortunate that i am not able to post pictures of the entire construction process due to a virus attack in my computer crashing all my files. The speakers had been delivered back to the owner after the drivers and electronics were installed.