Hybrid Audio Technologies Legatia - Manual (Page 45)

Legatia User’s Manual ©Hybrid Audio Technologies Page 45 of 65
Lowpass (midbass): 300 Hz at 12 dB/octave Linkwitz Riley
Bandpass (midrange): 300 Hz to 6,000 Hz at 12 dB/octave Linkwitz Riley
Highpass (treble): 6,000 Hz at 12 dB/octave Linkwitz Riley
The only filtering on the board is mentioned above, and in essence are elementary highpass,
bandpass, and lowpass filters common in any three-way crossover design. As noted above, there is
no board-mounted equalization specific to one brand or type of midrange or tweeter, or common of
competitor’s designs where equalization correction (filtering) is added. The L3x can be used with any
number of drivers we produce (including any midrange, midbass, and tweeter from the Imagine,
Unity, Clarus, Legatia, Legatia SE, and Legatia Pro range of offerings). The more common uses for
the L3x are Legatia L6 or Legatia L6SE, paired with Legatia L3, L3SE, L4, or Legatia L4SE, and
Legatia tweeters, such as the L1V2, Legatia L1 Pro, or Legatia L1 Pro R2, but the design is not
limited to those uses and can be expanded to any number of possible bespoke three-way
configurations.
The L3x passive crossover networks incorporate asymmetrically arranged super high quality and low
tolerance metalized polypropylene film capacitors, air-core inductors, and low tolerance non-inductive
resistors. Even the massive lowpass and bandpass capacitors are super high-quality polypropylene
capacitors, nearly unheard of by today’s standards. No output level switches were used in the passive
crossover design because switches add a resistive effect and are typically of extremely low quality.
Additionally, “jumper pins” add an unnecessary pair of splices in the signal path to the tweeter, and
were not included in our design either. Rather, all tweeter level adjustments are done on the board
level with dedicated non-inductive resistors; tweeter attenuation is accomplished by selecting the
appropriate output (-3 dB, 0 dB, or +3 dB) on the passive crossover circuit board. Likewise, midrange
attenuation is accomplished by selecting the appropriate output (0 dB or -3 dB). The components
selected are complimentary and ensure no appreciable signal degradation between the input and
output side of the crossovers. Likewise, the capacitors and inductors are arranged on the board to
reduce the coupling between circuits and electromagnetic interference by basic physical separation,
while still keeping the footprint size of the circuit board small. Finally, the use of 12 dB/octave filters
on both low pass and high pass minimizes phase-related distortion typical of crossovers with
mismatched orders, and ensures relative phase-coherency.
Connection
The L3x has convenient spring-loaded terminals for wire connection. Bare wire can be twisted tightly
and inserted into the spring-loaded terminal, however Hybrid Audio recommends that the wire be
tinned with solder to avoid oxidation, fraying, and to promote a better connection. The following is the
connection nomenclature on the L3x, from left to right on the circuit board:
+WF
Woofer positive input from amplifier
IN - Woofer negative input from amplifier
+WF Woofer positive output to Hybrid Audio Technologies midbass or midrange positive terminal
OUT - Woofer negative output to Hybrid Audio Technologies midbass or midrange negative terminal
+M/TW Midrange and tweeter positive input from amplifier
IN -
Midrange and tweeter negative input from amplifier
+M/H Midrange positive output to Hybrid Audio Technologies midrange positive terminal, 0 dB
setting
+M/L Midrange positive output to Hybrid Audio Technologies midrange positive terminal, -3 dB
setting