Series Crossovers: "reactively balanced"?

[clm811]

I've been toying with the idea of a system balanced from input to output, and experimenting with balancing a crossover network in order to try shielded twin lead loudspeaker cables (I live in a high-RF area).

While reading some old literature from Fried Loudspeakers I came across these statements regarding their choice of the series crossover topology:

{Series Crossover} provides several advantages listed below:

Balanced reactively providing a purely resistive load to the amplifier, which allows greater power transfer at critical dynamic moments.

Impedance curve is flat rather than having large peaks at the crossover frequency that are reactive and destroy transient response.

Drivers stay in phase providing sharper leading edges to transient sound as they are connected to each other forcing them to work in unison.

Active impedance of the speaker drivers at the crossover frequency is stabilized so that power is shared more predicatively{sic} between speaker drivers.

Actual measurements registered a 6dB increase in dynamic range when comparing series to parallel networks in the same system

I know that marketing print is full of hyperbole, but...

Does anyone have experience/opinions on the veracity of these statements?

-Chas

[Spatz]

The so called "advantages" are mostly not true:

A purely resistive load would mean a flat impedance curve. Serial XOs, balanced or unbalanced don't have a flat impedance curve. You can work with RCL and RC filters to get an resistive load, but for non-tube amplifiers, this is mostly unnecessary.

The phase of the driver is further influenced by the position of the driver and its filtering. As soon as you filter a driver, the phase changes... If you want drivers to be in phase, you have to work with electrical or mechanical delays.

The increase in dynamic range is the biggest lie, how can a woofer move four times more air in a certain frequency range just by having a different XO?

Bye,

Spatz

[evsentry3]

You might find it interesting to read through this thread.

http://thecarversite.com/yetanotherf...g=posts&t=2124

Primarily a review of a book that dives into this topic.