"Since it is equipped with high-class preamp, this player may also double as the heart of a small, but very fine high-end system."
Odd that Burmester 089 should have been great direct, as recommended by the manufacturer. As it’s output is a 60 position VC active preamp with a switchable tape input also, as these spec show with 4v low output impedance you defiantly don’t need to run a preamp into another preamp with even more gain from the second preamp. Their must be another reason, preferred additional preamp, coloration perhaps
https://www.i-fidelity.net/en/test-reports/high-end/burmester-089/labreport.html
Output voltage: 4.1 V
Channel deviation: 0.035 dB
Output resistance: 256 Ω
DC output offset: < 0.5 mV
Cheers George