Scan Speak Reference Monitor

[keyser]

Hi!
I've bought the parts to build a set of SS Ref. Mon.'s (with Revelator) as on the following site:

http://www.audiocomponents.nl/speake...erence_eng.htm

I've got plenty of nice 25mm (1") HDF.
The original Monitor is also constructed of 25 mm thick, only be it MDF. This box has no internal bracing at all. The version i'm going to build will atleast be thoroughly braced. I'm just not sure about the thickness of the panels. I'm thinking of using double layers of wood, as I got plenty of it, and the bigger size doesn't matter to me. What do you guys think?

[keyser]

and a pic of the woofer

[UrSv]

When you say "bigger size" I assume that does not apply to the volume or the front of the speaker since changing any of those will mean that a new filter is needed most likely.

[keyser]

that IS actually what i mean. when i make the box bigger, 25 mm in all directions, the front also gets 5 cm higher and wider. is it really so that the crossover is specifically made to fit this boxdesign? the designer of the speaker atleast says it is no problem to cut off edges of the cabinet, to give it an avalon-look. why would it be detrimental to the sound if i make the front bigger?

[jomor]

do not change the size of the baffle or the internal volume of the box. The low pass filter has a 2.2mH inductor, typical value for baflfe step correction for 8ohm 7" woofer at standard
baffle width. You will alter the bass response if you make changes. If you have to make changes, these should be as small as possible. 5cm wont make massive difference, but it will make some difference

[UrSv]

AFAIK, the filter is developed for a specific cabinet and baffle step correction implemented for a correct response with that cabinet. If you alter any front dimensions, including cutting off the edges, you will potentially ruin the whole speaker. I would not recommend altering the front dimensions or volume. Don't take my word for it though, hopefully some proficient speaker designer will chip in...

[LineSource]

Hi keyser,

The picture of the cabinet on the website has very sharp edges on all front planes. Many designers and simulation tools would have data showing sonic value for large radius edges. You may want to research this. Thicker walls with large radius edges may perform better than the original cabinet.


Your HDF should be denser and heavier than MDF, and should perform well with clever bracing. You should be able to make the front baffle thicker and adjust to total volume to compenate for your bracing with no changes to the crossover.

[keyser]

Hi Linesource,

the original cabinet does have slightly rounded edges, but i doubt the radius is large enough to be of any significance.
Yours was the answer I was hoping for, ofcourse... but what about what UrSv says? Is the crossover made to fit the dimensions of the front baffle?
And would a 50 mm opposed to 25 mm panel give an audible advantage? or would it not be worth the effort.
I have already calculated the needed inside dimensions of the box to contain bracings.