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Zesto Audio

Eros 500 Select Class A Tube Monoblock Amplifiers

Eros 500 Select Class A Tube Monoblock Amplifiers

Regular price $57,500.00 CAD
Regular price Sale price $57,500.00 CAD
Sale Sold out

Eros 500 Select Key Features

  • Sextet of KT150 output tubes create 250 watts of Class A musical power.
  • Class A power is fast for a more lively, immediate response to your music
  • The Bias Select switch is engineered with 3 perfect auto bias settings for KT88, KT120, KT150 and KT170 output tubes.
  • The Bias Select switch is safe and easy to use, change on the “Fly” so you can hear the difference.
  • 4 Ohm and 8 Ohm taps gives you options for your speaker preference. 4 Ohm may give you more base and the 8 Ohm tap may sound more open.
  • The optimized frequency response provides the best musical range to benefit the natural harmonic structure of the instruments
  • The SpeakOn cable connector provides most reliable hookup for your subwoofer.
  • Transformer balanced true differential XLR input offers noise cancelling and rejection, as well as providing ground isolation from your preamp.
  • Should you need to eliminate a hum? The Eros 500 has a XLR ground switch installed for your safety. This eliminates the dangerous temptation to lift the ground from the mains.
  • The combo Push-Pull and Ultra Linear circuit design provides lower distortion, more power, and a better performance out of your tubes.
  • No Negative Feedback in the circuit design provides better dynamic range because it doesn’t compress the music.
  • Non-inverting polarity retains the same phase as the input (so your trumpets blow and don’t suck)
  • Large Custom Toroid power transformer provides plenty of available power.
  • Toroids have lower noise because they concentrate the magnetic field and are very efficient in the 50 to 60Hz mains range.
  • Choice of high quality gold plated Single Ended RCA or Balanced XLR connectors to suit your needs or cable preferences
  • Gold pin sockets are more reliable because gold doesn’t oxidize when it heat cycles.
  • An extensive grounding scheme is designed into the power supply, wiring and all tube circuitry.
  • Elegantly designed, heavy duty 14 & 16 gauge zinc plated, fully grounded steel enclosure isolates external noise and vibration.
  • All fuses are easily accessible
  • It’s ready to enjoy with 50 hours of factory burn in on all circuits and vacuum tubes.
  • Each unit is hand built “Made in the USA”

 

        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 = 125 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 8 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
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