New Zesto Audio Eros 500 Select Monoblocks.

Zesto Audio is pleased to announce the launch of their new Eros 500 Select Monoblocks, quite possibly the most powerful Class A tube amps available. Each amp has 250 watts of dynamic Class A power. The Eros 500 Select ships with KT150 output tubes, but has the perfect auto bias to accommodate KT88s, KT120s and KT170s.

Specifications per amp (based on KT150 tubes)

Output
  • Pure Class A, Push-Pull Ultra Linear design
  • 250 Watts per amp
  • 4 Ohm and 8 Ohm non-differential output taps
  • Three 5-way binding posts
  • 10 Amp and 7 Amp Slow-blow speaker fuses (6mm x 32mm)
  • Non-inverting output polarity
  • SpeakOn connector for a subwoofer
  • SpeakOn subwoofer cable specs: Pins +1 and +2 go to the 8 Ohm output and pin -1 goes to ground
  • Power rating for Auto Bias Select Switch Settings
Left Position:
KT88 = 150 Watts per channel
KT120 = 150 Watts per channel
KT150 = 150 Watts per channel
KT170 = 150 Watts per channel
Middle switch position:
KT150 = 200 Watts per channel
KT170 = 200 Watts per channel
Right switch position:
KT150 = 250 Watts per channel
KT170 = 250 Watts per channel
Inputs
  • Transformer true balanced differential input
  • XLR gold pin balanced input with pin 2 hot, impedance 12K Ohms
  • RCA gold pin single ended input, impedance of 12K Ohms
  • XLR ground lift switch
  • 3.3 Volts RMS input to reach rated output
  • Detailed Specs
  • Monaural
  • Auto bias
  • No negative feedback
  • Frequency response 20Hz to 30Khz ~ 3dB
  • Total Harmonic Distortion ~ 0.07% at 1W into 8 Ohms
  • Gain of 27dB
  • Noise level > 4 mV RMS into 8 Ohms with input shorted
  • 1% metal film resisters throughout
  • Polypropylene capacitors throughout the signal path
Power
  • Large custom Toroidal power transformer
  • 120 Volts AC mains with 10 Amp 5mm x 20mm slow blow fuse
  • Mains fuse located in drawer compartment of IEC power connector
  • 3 pin 15 Amp IEC power inlet connector
  • Optional factory installed 220V, 230V/240V 50/60Hz with 6.3 Amp slow blow fuse
  • Power consumption at rated output 756 Watts
  • On/Off switch conveniently located on front panel
  • Amber LED low voltage and green LED high voltage indicators
Active Components
  • Six (6) KT150’s vacuum tubes
  • Two (2) ECC82 (12AU7) vacuum tubes
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 (43.1 cm x 25.4 cm x 50.8 cm)
  • Weight 79 lbs. (35.8 Kg)
  • Shipping weight 96 Lbs. (43.5 Kg)
  • Shipping box 27″ W X 27″ D X 13″ H (68.5 cm x 68.5 cm x 33 cm)
  • 16 and 14 gauge Zinc plated steel enclosure
  • Two year limited warranty
  • Six months warranty on 12AU7 Vacuum Tubes, 90 day warranty on KT150 power tubes