it is, but i still don't have any good method of measuring the light output. haven't researched how manufacturers carry out their measurement to come up with their lumens per watt rating.

i do have access to a lux meter, but need to build a makeshift reflector to channel the light and avoid diffraction. so for now it's just relative comparison when the room lights are turned off and the sample lamps turned upwards to light the ceiling.

nice to see another engineer. the led lights are freakin simple to construct. can even build ourselves DIY style.

It is good to know the actual running watt. Sometime really difficult to believe what they claim. Specially for the LED.

Is this the actual watt for the led light 18w? Or their state spec? What is the lumens ? How is the Amp measure before and after the power supply?

i see lots of housing over here have crack forming on the wall under a year.
some people say red clay brick have better insulation against heat by sunshine. better cooling effect.

wife says red clay bricks have better heat retention ability, thus frequently used in western countries. they absorb heat during the day, making the house cooler during the day but they excrete the stored heat during the night. thus heating the walls making it warmer. a welcomed trait for western countries where night time is very cold and it would reduce the heating costs.
not exactly an appealing proposition for the weather here.

anyway we're planning for AAC bricks for the west facing walls to improve the insulation. it's only ~60 feet of walls that face the evening sunshine. and the rest of the house probably the normal cement bricks. undecided yet.

it's normal for contractors to ask for >RM100 for a complete build. usually RM120-RM130 psft including tile, ceiling, paint, etc.
mine at RM32 psft, but there's no roof, no windows, no doors, no bathroom utensil, no tile, no wiring.

pretty much the basic structure only. we're gonna be our own main contractor. it's DIY from start to end
it's a dual 15 inch ported sub tuned to 20hz. each powered by a 600w class d amp.

null because of the sub response, or amp response could be corrected. but a large null because of the room could never be corrected by a brute force solution. i (we) have experimented to correct a huge room null by giving the sub 4x the power, it only improves the response by 2db. 400% more power, only ~5% correction.