A101 – AnalogWorkshop

Replacement Modules

A101 - Discrete Op-Amp - Replica

Studer, a brand that has become legendary in the audio world. Devices manufactured by the Studer company enjoy recognition to this day, and the quality of workmanship exceeds the competition.

Unfortunately, even devices of this class sometimes require repair. And so, there was a need to produce a discrete op-amp, the A101 replica.

The A101 discrete op-amps are used in Studer A80 reel-to-reel tape recorders.

The A101 replica has several improvements compared to the original module:

Instead of through hole elements (THT) we use surface mounted elements (SMD). SMD components have shorter leads, thanks to which they have lower parasitic inductances. In addition, the module has smaller dimensions (thickness).

Low-noise BC850 and BC860 transistors were used.

The electrolytic capacitor, the most defective element in the original modules, has been replaced with a ceramic one of the same value, thus guaranteeing maintenance-free operation of the A101 opamps made.

All resistors have been selected with a tolerance of 1%, thanks to which the modules will work identically.

Gold-plated contact pins, soldered to the PCB, were used as the leads, so that the original lead spacing was maintained.