Originally Posted by Glimmie
The Marchand gear is excellent. Well engineered. The XM66 is a new product and I'm sure it's performance is excellent too. But keep in mind while the variable frequency control is neat, the analog techniques to do that are often less than ideal audibly. If you know the crossover frequency needed, you could go with one of his fixed units. And they really aren't fixed, they just require some small boards be swapped out for different frequencies.
The other route is to go with a DSP based digital crossover. Here the crossover is mathematically perfect within the constraints of the data width. However now we have an analog to digital conversion and back. So that too can compromise the fidelity.
Wayne Highwood recommended miniDSP but I actually prefer the XM66 solution. Regarding the crossover frequency, I'm not sure about it. That's why I may be choosing the variable frequency control capabilities of the XM66.
In any case, my three way Revel crossovers are specified at 190Hz and 2900 Hz, so I'm thinking of playing with active crossover frequencies starting at 100Hz (active crossover for the lows and pasive for the mid-highs).
Just FYI, the variable frequency Marchands unit XM9L costs a little bit less than the variable frequencies XM66, both using 24 step attenuators.
I can't believe the price of Marchand products. Rane makes a number of different 2 and 3 way active crossovers with continuously variable frequency controls. They perform well. They can often be obtained for reasonable prices on eBay and other used equipment sites.
Well Arny, I've never used a RANE product but my preamp and my amps use single ended connections. RANE's are balanced.