BiAmpPro
The
BiAmpPro is a full featured module for 2-way Active
speakers. At heart is an asymmetric electronic crossover
set at 2.5kHz. High pass to tweeter is at 18dB/oct
whereas to the woofer is 12dB/oct.
What
is unique about this crossover is that the high and
low pass filters are part of the power amplifiers.
No op amps are used to achieve this crossover. Neither
are they Passive Line Level Crossover, aka PLLXO.
SGS Thomson, the manufacturer of the TDA2030A and
TDA2050 chip amps used in the BiAmpPro, calls this
crossover "Active Power Speakers".
In
this BiAmp configuration, a TDA2030A is used for the
tweeter. For the woofer, two TDA2050 in Bridged mode
are used for higher power. Note that the woofer must
be 8Ω, not 4Ω. That's due to the nature
of Mono Bridge because each TDA2050 will be seeing
4Ω.
The
BiAmpPro has her own Power Supply. The transformer
secondaries feed a 8A bridge rectifier followed by
4 pieces of 3,300uF filter capacitors, totaling 13,200uF
of smoothing caps.
The
line input is electronically Balanced so that long
signal lines can be safely run without picking up
noise. A pair of voltage regulators (7812/7912) ensures
the op amp supply is stable and clean.
There
is provision to adjust the level of the tweeter so
that it matches that of the woofer. Without this,
the tweeter will be too loud.
Woofer - 1kHz Full Power into 4Ω |
Tweeter - 10kHz into 4Ω |
BiAmpPro
Specifications
Tweeter
Power Output = 12W into 4Ω
Woofer Power Output = 24W into 8Ω (mono-bridge)
Woofer Input Sensitivity (@ 1kHz before Clip) = 0.35V
RMS into 8Ω (Bal) | 0.7V RMS into 8Ω (UnBal)
Voltage Gain = 27dB
Power
Supply Specs
Power transformer = 12-0-12Vac
Supply Rails = +/- 16Vdc
PSU caps = 13,200uF (4 pcs of 3,300uF / 35V)
PCB
= 5.1" X 2.75" (130mm x 70mm)
Double Sided | FR4
The
BiAmpPro is one channel and is supplied
Unassembled. Two kits are required
for stereo.
To
complete the amplifier, the following are
needed
1) a power transformer
2) a heatsink for the TDA2030A and TDA2050
chip amps
3) a metal case and the necessary connectors
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