THE ORRONOCO AUDIO DIY

Since last year, I have been focused on building my own tube amplifier, especially using 300B tube in the single-ended configuration. I got more enjoyable moment when listening music through the tube amplifier instead of solid-state amplifier, especially with the 300B tube amplifier. The sound is more musical, more engagement to the music, and human voice alike compare with the solid-state amplifier. Previously, I also had experience using others tube such as 2A3, KT88, 6L6 and EL34, but I still believe the 300B is a holy grail of all tubes, so I stick to this choice. 300B tube is  direct-heated tube (DHT) , meaning this tube heater also act as the cathode. In the single-ended amplifier, using DHT tube will potentially contribute the hum to the speaker. This is because the power supply voltage along with the noise feed into the heater tube and direct impact to the cathode itself. Annoying hum needs to take care. I took so many lesson when building several 300B amplifier before...

This is the following post regarding building the miniaturized DAC that should sound good, just like full-size desktop DAC. But the difference is in the small chassis. The reason for this is because in my opinion, a DAC unit is not to be shown as the main show unit in the audio system. So let it be hidden somewhere else at the back of the system and let the tube amplifier, speaker and source player as the part of the main show in the audio system. In this post, I will make another DAC using the components that what I have left in my bin. I think in this post, the description will be more in technical. I will try to explain the building concept for the good sounding DAC based on my experienced. This build will be more complex, harder to follow for beginner, but for some reason, I just want to do it. So, let's begin for this AD1865 miniaturized DAC build.

It is been a while I am out of making a DAC. I am enjoying what I have right now and just listening the music through my audio system. My audio system is consisting of the 300B amplifier and DAC that sitting next to it. I was thinking that the DAC not the main unit to be shown, but the 300B is. The DAC is basically a simple and plain box that convert the digital to analog. I look at many commercially available DAC and they are all physically look the same. Many of them have only LEDs to indicate the sampling rate, inputs, and operation status. Few of them have their own LCD to show the same things like LEDs but in more fancy display. if we're honest to ourself, that display or LEDs indicator are not really important, especially when we listening to the music and enjoy it. So, I want to try something new in this DAC project. The things that more universal and easier to use, rather than a bulky DAC box unit. This DAC project should be small enough to hide away from the main show of t...

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...

Welcoming this year, I always hope that this 2026 will be blessed with joy and happiness, with all things we are doing, we doing with fun and excitement. For the past week, I actually got flu and not really into this hobby for quite long time. But I was concerning to revisiting this newly built amplifier again. Is not 100% complete, few things need to change and add to suit my sound preference. So, here it is. The new updates for this 300B amplifier.