Справочник Пользователя для Sound Performance Lab GOLDMIKE MK2 2485

The solid stage preamp section is based on a fully discrete, 
balanced instrument amplifier and operates 12 single transis-
tors in class A mode. A sophisticated circuitry ensures a nearly 
constant frequency response at any gain level. With an impres-
sive slew rate of more than 200V/µs the solid stage is capable to 
amplify highest frequencies and fastest transients with almost 
no distortion, which is crucially important to achieve a realistic 
sound experience. Coupling condensers were used as spar-
ingly as possible to avoid their inherent disadvantages such as 
diffuse sound, slurring and loss of dynamics. To eliminate DC 
artifacts, these are replaced by servo circuits operating outside 
of the audio signal paths.

An  op-amp  subsequently  converts  the  instrument  amplifier’s 
output signal into an unbalanced one, which is then fed to the 
tube.  Here  an  additional  +6 dB  tube  amplification  is  added, 
switchable to +12 and +18 dB with the Tube Amp function.

The tube type—a Sovtek® 12 AX7 LPS—was also selected after 
extensive measurements and listening tests. This tube type 
outclasses the standard 12 AX 7 by far and delivers an open, 
transparent sound, excellent noise values and is especially reli-
able. An impedance converter adapts the tube’s high-imped-
ance signal to the following stages.

The output stage can drive very long connections (depending on 
cable capacities, up to several hundred yards). The max. output 
level is at +26 dBu, allowing plenty of headroom to drive subse-
quent converters.