MA LS90-MP Desktop Monitor

This project was built by following the guide from MA.

• By trial and error we ended up tweaking a little bit the final design of the electronics.
• Paper in Oil caps were used.
• The box was dampened with Alu-butyl and wool.
• Black shiny finish 🙂

Here is the guide that was used:

Markaudio LS90-MP – Sealed box bookshelf

homage to BBC LS3/5a for CHR-90 & CHP-90 5in fullrange

• Designed to reference BBC LS3/5a dimensions
• 12mm thin-wall side, top, base & rear baffles with 18mm front baffle to accept driver basket with enhanced stability
• Chamfer driver cutout to reduce reflections & improve airflow
• All internal panels apart from front baffle lined 2mm – 2.5mm car body damping sheet / bitumen acoustic damping mat. If self-adhesive, recommend using own glue to reduce chance of delamination at future date
• Top, rear & base lined over car body / bitumen damping with 25mm – 30mm bonded acoustic fibreglass board, wool felt, BAF wadding or equivalent.
• Side panels lined 12mm – 15mm bonded acoustic fibreglass board, wool felt, BAF wadding or equivlanet.
• 12mm void-free multiply recommended for main box. Front baffle may be void-free multiply or HDF
• CHR-90 or CHP-90 may be used to preference, with small change in system Qtc.

Crossover components:

• C1 = 10uF MKP
• L1 = 1.8m 14ga air core
• R1 = 6.80hm – 100hm 10w. Adjust value to adapt
• midband voicing to taste

Please see dimensions in the pictures.

If you read till here, there are a few videos available with the in-dept build quality.

Build Quality & paint finish – this video was made during the last testing. notice the screws.

Random song 1, Random song 2, Random song 3

I hope you enjoyed it. Feel free to comment