Zesto Bia 200 Select Stereo Power Amp

Key Features

• The Bias Select switch is engineered with 3 bias settings for 4 different output tube
• Compatible with KT88, KT120, KT150 and KT170 output tubes
• Bias Select switch is easy to use, change on the “Fly” so you can hear the difference
• Auto Bias is safe, consistent and settings are always perfect
• Class A power is fast for a more lively, immediate response to your music
• 4, 8 & 16 Ohm taps gives you options for your speaker preference
• Dual Mono gives you less cross talk and better stereo imaging
• Choice of high quality gold plated Single Ended RCA or Balanced XLR connectors to suit your needs or cable preferences
• True transformer differential balanced XLR inputs for the best noise rejection
• Independent Left and Right ground switches on the XLR balanced inputs to eliminate ground loops and hums
• No Negative Feedback design does not modify or compress the musical signal
• Large custom Toroid is higher voltage for increased performance and lower noise
• Global mains power supply can work all over the world
• Provides plenty of gain for your system
• Push-Pull/Ultra Linear circuit design provides lower distortion, more power, and a better performance out of your tubes
• Low noise levels allow really dark black quiet musical passages
• Non-inverting polarity retains the same phase as the input (so your trumpets blow and don’t suck)
• Gold pin sockets are more reliable because gold doesn’t oxidize when it heat cycles
• Matched quad KT150 output tubes retain the stereo balance and lower noise
• Elegantly designed, heavy duty 14 &16 gauge zinc plated steel enclosure to accommodate the extensive grounding scheme
• The optimized frequency response provides the best musical range to benefit the natural harmonic structure of the instruments
• All fuses are easily accessible
• Each unit is hand built “Made in the USA”

Specifications (based on KT150 tubes)

Output

• Class A
• KT150 = 100 Watts per channel into 8 Ohms
• 4 Ohm, 8 Ohm and 16 Ohm output taps
• 10A, 7A and 5 Amp 6mm x 32mm Slow-blow speaker fuses for outputs
• Eight 5-way binding posts
• Non-inverting output polarity
• Push-Pull Ultra-Linear design

Power rating for Auto Bias Select Switch Settings

Left Position:

• KT88 = 60 Watts per channel,
• KT120 = 60 Watts per channel
• KT150 = 60 Watts per channel
• KT170 = 60 Watts per channel

Middle switch position:

• KT120 = 85 Watts per channel
• KT150 = 85 Watts per channel
• KT170 = 85 Watts per channel

Right switch position:

• KT150 = 100 Watts per channel
• KT170 = 100 Watts per channel

Inputs

• Transformer floating ground differential balanced XLR inputs
• Left and right balanced inputs (pin 2 hot), impedance 10K Ohms
• RCA single ended inputs Left and Right with impedance of 47K Ohms
• Independent ground lift switches on left and right Balanced inputs
• 5 Volts RMS input to reach rated output

Detailed Specs

• Dual Mono
• Auto bias
• No negative feedback
• Frequency response 20Hz to 30Khz ~ 3dB
• Total Harmonic Distortion ~ 0.22% at 1W into 8 Ohms
• Gain of 24dB
• Noise level > 2mV -RMS into 8 Ohms with input shorted
• 1% metal film resisters throughout
• Polypropylene capacitors throughout the signal path

Power

• Custom Toroidal power transformer with global mains
• 15 Amp IEC power mains connector
• 120 Volts AC mains with 8 Amp 5mm x 20mm slow blow fuse
• Optional factory installed 220V, 230V/240V 50/60Hz with 4-amp slow blow fuse
• Power consumption at rated output 517 Watts
• Front panel on/off switch with green LED indicator for high voltage and amber LED for low voltage

Active Components

• Matched quad set of four (4) KT150’s vacuum tubes
• Four (4) Gold pin ECC82 (12AU7) vacuum tubes
• High quality gold plated ceramic sockets

Other Features

• Each unit is made by hand
• 50-hour factory burn in on all circuits and vacuum tubes
• Dimensions 17″ W X 20″ D X 10″ H
• Weight 64 (29Kg)
• Shipping box = 27” x 27” x 13” (5 cm x 68.5 cm x 33 cm)
• Shipping weight: 80 pounds (36 kg)
• 16 and 14 gauge Zinc plated steel enclosure
• Two year limited warranty
• Six months warranty on Vacuum Tubes