LaChappell 583e

The Model 583E features the same amplifier stage found on the 583S including the Jensen JT-115k input transformer coupled with an ultra-clean transformer-less three-band EQ section with fully sweeping frequency controls and cut/boost settings of +/- 8dB.
The EQ can run as an integrated EQ serving the preamplifier or separate as its own autonomous module where both units run independently.


LaChappell 583e Features :

• True Vacuum Tube Amplifier.
• Jensen Microphone Input Transformer.
• Nickel/Alloy Output Transformer.
• Accessible Tube Section.
• Integrated OR Independent 3-band EQ.
• Fully “sweepable” EQ Frequencies.
• Extremely Low THD+N Performance
• Transformer-less EQ Section
• Premium Components

The LaChapell Model 583e and 583s are the first 500 series vacuum tube preamplifiers and are based on the popular LaChapell 992EG platform.
The input stage is a traditional single-ended type utilizing a 1:10 microphone input transformer along with one ECC83/12AX7 vacuum tube and the output stage utilizes premium Burr-Brown and THAT Corporation balanced line drivers.

LaChappell 583e Specifications :

Mic Preamp Specs :

    * Internal Gain: 0 - >70dB
    * THD+N: < 0.25% (Gain @ 5dB, 0dBu output)
    * Frequency Response: 12Hz-70kHz (-3dB, output favored)
    * Maximum output: +26dBu (1% THD+N)
    * Noise/EIN: -120dB (Rg=150ohm, 22Hz-20kHz)
    * Input impedance: (Mic) 1.5k ohm, (Hi-Z) 40k ohm
    * Tube compliment: ECC83 (x1)

EQ Specs :

    * Description: 3-band EQ with fully sweepable frequency control; fixed 'Q' value of 1 with very low phase deviation
    * Input/Output type: transformer-less; ultra-clean with minimal harmonic signature
    * Input impedance: 40k ohm
    * Output impedance: 50 ohm
    * Bands:
          o Low: 30Hz-400Hz
          o Mid: 325Hz-5kHz
          o High: 2.5kHz-20kHz
    * Cut/Boost: +/- 8dB
    * Max input: +24dBu
    * Max output: +26dBu
    * Self noise: -93dB
    * THD+N: 0.012% (with +8dBu input signal)