1 plus 1, Various, monitor 4 to 1+1

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Alan Kelly2004-02-23 22:21

I have reconfigured my Monitor Four speakers to a 1+1 using one wide panel at the bottom and a narrower panel at the top. Does this arrangement make sense ? Or should I stick to using equally wide panels top and bottom ? Which one to use the narrow or the wide ? Can anyone tell me the dimensions of the panels in the 1+1 ? I am listening in a small room otherwise I might have gone to 2+2. Thanks in advance Alan.


Andy Szabo2004-02-23 22:21

The Monitor 4 used four ESL panels per speaker, of two different sizes. The two outer panels are 9-inches wide, and the two inner panels are 8-inches wide. Other than the width, the two types of panels are of the same construction and performance. The purpose of the two different size panels was to distribute the low frequency resonant point. In later models, this was found to be unnecessary, and hence models like the 2+2 used all 9-inch panels.

The Model 1+1 uses two 9-inch panels, stacked vertically.

In converting the Monitor 4 into a Model 1+1, I would recommend using the two 9-inch panels. Since the 1+1 has barely enough panel area for adequate bass response, you\'ll want to employ as much panel area as possible.

In converting the Monitor 4 into a Model 2+2, I would recommend using the two 9-inch panels stacked vertically in one column, and the two 8-inch panels stacked vertically next to them. For the other speaker, make the arrangement mirror image. It probably doesn\'t matter whether the narrow panels are on the inside edges or the outside edges, but I would probably put them on the inside edges. The two columns of panels should have an angle between them of about nine degrees.

For the 1+1, you\'ll want to change the position of the Low Frequency Transformer Tap. (This is assuming you are using the MK-121 transformer interface, and not the Servocharge Amplifier.) The tap is normally set on the Yellow position for a four-panel system (minimum bass boost); you\'ll want to change to the Red position for a two-panel system (maximum bass boost).

One real difference you\'ll notice in going from the 4-panel wide Monitor 4 to the one panel wide 1+1 is a dramatic improvement in stereo imaging, since the 1+1 more closely approximates a line source.

Good Luck. This sounds like a fun project. Old Acoustats never die: they just take on new shapes!

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