Mentor Monoblock 300B (Quad C-Core) Page Under Construction


The new Mentor  Series 300B monoblocks

SKU: 300B-INT-MONO-1 Categories: , , ,


The new Mentor  Series Monoblock: modestly priced, exceptional value and loaded with quality. The sound is reserved for customers seeking zero feedback, single ended triode amplification! With both 8.5W and 20W versions available this product

Email us at for further details or ordering information

ANK Audiokits

Birth of the Mentor MonoBlocks SET

We released the Stereo Mentor 300B Power amp a few years back offering 8W of pure 300B SET in a mentor style (pre-amo) chassis . The product has been very popular and we decided in 2022 to develop the MonoBlock version of this – Now two mentor chassis each housing the Power supply , output quad ccore and 300B signal path – with the mono block you can now have Parallel SET operation ( 15W) or single 300B per chassis ( 8w) . The build is straight forward with the 300B section harwired like on the kit1 and PCB for the 5urg rectified power supply and driver board – the driver board has room for large AudioNote copper film capacitors and tantalum resistors -the BLOCKS are low gain and dead quiet and a fantastic mate with the mentor or L3 pre-amp


The Mentor Series Monoblock Single Ended amplifiers employ a 6SH7 driver tube wired in a pentode configuration to successfully drive a Parallel or Single Triode 300B.

  • Single 300B Amplification 8.5W Single Ended
  • Parallel 300B Amplification 18W Single Ended

The sound of SET in a compact chassis

The Mentor Monos  deliver that gorgeous zero feedback Single Ended triode sound. Simplicity is the key to the circuit of the amps and targeted at higher efficiency speakers they provide remarkable sound quality to rival the best of SET amplifiers yet do this at a real world price. A remarkable achievement!

. They are a pure power amp with approximately 2V sensitivity and ideal when mated with our L3 L4 L5 Pre-amplifiers. The classic 5U4G rectifier tube smooths the AC for the power supply. DC filaments and a large 300MA power supply choke installed inside the chassis assures dead quiet operation!


Power 8.5 Watts Class A (Single 300B)
18-20 Watts Class A (Parallel 300B)
Output Tubes 2 x 300B or 4 x 300B
1st Stage Gain 6SH7
Rectifier Tube 5U4GB
Inputs 1
Outputs 1 x Stereo Pair 4, 8 ohms
Recommended Speakers min 88dB
Chassis 3mm Aluminum with Black Powder Coat

Parts Compliment includes:

  • Audio note  1W 2w Resistors
  • Mundorf 100+100 & 30uf 600v Power Supply Capacitors
  • Panasonic FC series cathode caps
  • PTFE Silver Plated Hookup Wire
  • Shuguang 300B Tubes
  • Audio Note Speaker Posts & RCA’s

Additional information

Mentor 300B Monoblock

Mentor SET MB 8.5W (Pair), Mentor PSE MB 18W (Pair)