Cabinet Design continued / Assembly Tips:

Jim:
It's important to have the seated ear height correspond with the area
between the W4 mid and the ribbon for best sound quality. The W4 carries
much of the vocal range and nearly all of the midrange harmonics so
positioning is important to have this at ear height. The end result is a very
large, expansive soundstage and a wide sweet spot for the listeners. All of
the Statements series designs are to be listened to off axis and positioned
pointing straight ahead with 1 ½" of distance from the back of the speaker
to the wall behind them. They will work surprisingly well closer but further
out is better. The Monitors have gone a step further. Curt waved his magic
wand and created not only a far wall version that is designed to be used
out into the room but also a near wall version that can be used as close as
12" from the wall to the back of the cabinet. In addition, he designed a
'switchable' crossover version that allows complete flexibility of placement
by inserting a switch on the back of the cabinet that selects the proper
crossover. Very cool!

The Monitors require less than one sheet of ¾" MDF to build. A ½" sheet is
required to combine with the ¾" front baffle to end up with a final thickness
of 1 ¼" which I've found to work extremely well for this size of driver. I used
a ¾" round over on the vertical front edges of the cabinet to smooth
frequency response and to also allow standard paper back veneer to wrap
around the sides and front to eliminate visible seams. The veneer on the
bottom and back should be installed first and most cabinet builders will
attach the top veneer last to put the visible seam below eye level. I might
also add that it is very important to scallop or round over the inner side of
the front baffles of the driver openings to help eliminate any tunneling
effects. This is particularly important for the mids but I'd suggest you follow
this practice on all openings for cone type drivers.

The Crossover:

Curt:
The Monitor crossover topology is, of course much like the rest of
the Statement series. The woofer / mid crossover emulates a 2nd order
acoustic LR at roughly 500 Hz, while the mid / tweeter is near a 3rd order
acoustic BW at 4 kHz. In this iteration, the midrange is electrically
connected out of phase, while the woofer and tweeter are connected with
normal polarity. The impedance minima is 3.3 ohms at just above 100 Hz,
but the majority of the impedance is above 4 ohms. I'd call this a 4 ohm
design, but if it were a commercial design, is suspect the marketers would
call it a 6 ohm impedance. The phase plot is again very similar to the rest
of the series with the mid and tweeter indicating they are near phase
quadrature over their shared frequency band. A new twist this time is a
crossover network optimized for Full BSC and fpr Partial BSC, as well as a
'switchable' version that allows the selection of either crossover at the flip
of a switch. The difference between the two circuits results in about 2 dB
increased sensitivity for the nearwall version above a couple of hundred Hz.
                                                                                            Continued....
Jim Holtz's:
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Click for response plots
Statement Monitor
Click here for the:
Far Wall Bill of Materials
Near Wall Bill of Materials
Switchable Bill of Materials
Click here for the:
Far Wall Crossover
Network
Near Wall Crossover
Network
Switchable Network