RPM Developments information page

KR is the world leader in the production of low-frequency power triodes and hi-end audio equipment.

All products are hand-crafted, starting from the selection of the glass. KR uses Simax hard glass exclusively for their tube envelops and internal supports. The high vacuum machines and the choice of the artisan work in both metal, glass blowing and design, chemical and electrical designs plus the absolute refusal to use an automatic line to make tubes is THE reason for KR unique high quality.

KR AUDIO TUBES:

KR Audio 300B Balloon

The 300B Balloon is a low frequency, high power triode tube. 300B Balloon is capable of producing 10-20 watts of pure class A power.

KR Audio 300BXLS

The 300BXLS is an ultra-linear, low frequency, high power triode tube capable of producing 15-24 watts of pure class-A power.

KR Audio 842HVD

The 842HVD is an ultra-linear, low frequency, high power triode tube capable of producing 12-22 watts of pure class-A power.

KR Audio 845

The 845 is a low frequency, high power, high voltage triode, capable of producing 20-26 Watts of pure class-A power. The 845 features a new ribbon filament construction and the KR Audio exclusive patent design with 32 cathodes.

KR Audio PX25

The PX25 is an ultra-linear, low frequency, high power triode tube capable of producing 6-10 watts of pure class-A power. A replica of the early PX25, this tube is available in both a UX4 base and the original 4 pin English base.

KR Audio T1610

The T-1610 is an ultra-linear, low frequency, high power triode tube capable of producing 22-45 watts of pure class-A power. The T-1610 is an exceptional tube for those special applications requiring a lot of class-A power.

RPM Developments Oy is a distributor and retailer for electronic parts and components. Tubes, Capacitors, Transformers, Connectors, Switches, Cables, Semiconductors, Test Equipment, Audio Equipment and Tools. Our happy customers are companies and individuals all over the world!