THE ORRONOCO AUDIO DIY

Since end of last year, my focus on this DIY audio is more on 300B tube amplifier. This kind of tube amplifier is well known as a holy grail of sound, and it is true. Then I remember I have one DAC project that need to be complete. It is the PCM58 DAC using the PCB ordered from PCBway.com. You might want to refresh the PCM58 DAC PCB that I mentioned in  here  and  here , those post are the first time I ordered the PCB from PCBway.com and that was the easy and enjoyable order experienced. So, let's begin this project.

Looking to this 300B amplifier built, it was designed with similar philosophy of Luxman MQ-300. The driver stage is 6SN7 tubes configured in parallel for higher current output, lower impedance and distortion. Instead the original Luxman MQ-300 using total 2-stages amplification in the driver stages, I only use a single stages. The reason for this is because the limitation in the chassis spaces. The sound quality for this 300B amplifier using a single stages 6SN7 in parallel is actually meet my expectation, but the gain is quite low. My listening loudness is around 55 to 70 dB maximum, not too loud, and the volume level position around 12 to 3 o'clock for 3-volt output from the source. This might be an issue for someone who looking for the gain, but for me this is still acceptable. The main issue for this amplifier is actually with the sound quality depend with the source level output. I am using my own built DAC or few commercially available source and not all of them can produce 3...