Who supplies tubes and service for Graaf units from Italy?

The Italian high-end classics from GRAAF are technically brilliant, but demanding. Since BTB was the tube supplier for Giovanni Mariani for many years, we know his units very well and know exactly which selections are necessary for stable operation.

Our expertise for your GRAAF classics:

OTL models (GM 200 & GM 20): For the Russian 6C33C triode, we supply specially selected, precisely matched sets that are essential for the thermal stability of these OTL circuits.

Special case GM 100: This unique unit requires a perfectly homogeneous matrix of 32 pieces 12AX7 (ECC83). We put together precisely matched large sets for this purpose.

Preamps & upgrades: Whether 6922 / E88CC, 12AX7 or 5751 – from the solid Sovtek basis to S4A or Genalex Gold Lion, we carry exactly what fits these concepts.

Giovanni Mariani sourced the tubes for his production from us for a long time. We know the requirements for the tube values of his models and help you secure the longevity of your units.