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View Full Version : Marchand Bassis - DIY Kit ?


grinchy
02-25-06, 08:37 PM
I'm thinking about adding a bassis to my simple dual 10" driver sealed Sony wx-700. Figure it might be able to eek out another octave or so.

I'm a fair hand at soldering, have you assembled the one board kit (i'm using it for a single sub at the moment)?

Any leads on where to acquire a 15V power supply?

Thanks in advance.

Jack Gilvey
02-25-06, 08:50 PM
I wouldn't bother, I doubt it has the power or displacement to do any more than it does, and likely has filters already cutting out that last octave. As I recall, going down an octave requires a quadrupling of excursion for the same SPL. Low FR is really neat, but means very little without useable volume, which means displacement/power.

grinchy
02-25-06, 09:31 PM
I don't know if it has such filters, though the dual 10s give it more surface area than a 12". which may keep the excursion needs in check. of course since it's off the shelf, I don't know what the driver excursion really is, but it has impressive surrounds :)

Let's say I like to fiddle and am curious about what it takes to assemble the base BASSIS for one channel - any one with experience in that?

steve nn
02-26-06, 09:36 AM
Any leads on where to acquire a 15V power supply?
Marchand will sell you one for around $35 if memory serves me correct? I opted for the Mono BASSIS after considering the final cost of the kit and the $other aspects of putting one together myself. My lack of knowledge in soldering circuits admittedly played a part in this discission.
As I recall, going down an octave requires a quadrupling of excursion for the same SPL. Low FR is really neat, but means very little without useable volume, which means displacement/power.
No doubt about it Jack.
I'm thinking about adding a bassis to my simple dual 10" driver sealed Sony wx-700. Figure it might be able to eek out another octave or so.
Since you have plate amps and onboard filtering, I don't think it wise for reasons already suggested. Plus two Sony 10" drivers will give up their excursion very quickly. What size room do you have them loaded in? Another nice feature of the BASSIS is the ability to change your Q though.

http://i3.photobucket.com/albums/y75/stevenn/100_1023.jpg

kgveteran
02-26-06, 03:46 PM
Have you measured the sub now to see where the rolloff is ? That BASSIS will suck every last bit out of those two sonies. My mono was 388.00 picked up.What do you have invested in the sub now ? You will lose the 25-35hz punch when those 10's are attempting to move 15hz or lower.Check out what they are doing and that will tell you how much is left in the tank.

grinchy
02-26-06, 07:57 PM
Here's the sub graph from REW - nothing special, of course.

I'm mainly just looking at playing around a bit, but as some previous poster's have said, perhaps the sub has filters that are already curtailing sub-20hz response. $388 completed is too much - I'm more looking at the $70 board and components. Add on $25 or so for the power supply, $5 for a DIY box, and it might be a fun toy. If nothing else, I can fiddle with Q.

I already took back my outboard sound card, so I can't remeasure right now using a lower freq sweep.

I was also looking at this L-T (http://sound.westhost.com/project71.htm) circuit at ESP, maybe that would be a better idea? It's about $30 for the board, plus components ($25 p/s, maybe $30 more the L-R-C)

steve nn
02-26-06, 08:20 PM
I'm mainly just looking at playing around a bit,
Thats how many of us learn along with taking good advice and applying it. I think what what we're trying to convey here is.. we would hate to see you fry what you have going for you now. It's a little like trying to bore out a piston wall thats already paper thin.