300B Tube Amplifier Build

The 300B tube can be the holy grail of every tube amplifier. Everyone praises for its sweet sound. Personally, I never compare directly between one amplifier to another amplifier using 300B tube, but I still believe the reputation of this 300B is not a false statement.

More specific, the single ended 300B design are well known for the best sounding amplifier compare with the push-pull. Single ended is also more economical approach since we only need a pair of 300B tubes. But it has the drawback, it is the low power output. It is about 6 watt per channel.

That is why in this 300B tube amplifier build, I will make this amplifier in single ended design with 6SN7 driver and 5AR4 rectifier to drive a headphone.

For headphone? Pretty disappointed?

I guess not. I hope the sweet sound of 300B can be heard more closely to my ears.

Fresh Catch, The Parasound DAC 1000

Sometimes we bought the vintage audio equipment's not because only for the built quality, or the sound signature, or the price. I bought this Parasound DAC 1000 because it looks just like new.

Parasound is the big name in 90's which at that time, I am just can saw it on the borrowed Stereophile magazine. So, when I saw this DAC today and sold to me for under $300, who can resist?!

IBASSO DX-90 Disassembly & The Capacitor Replacement

It has been a while I am not posting anything in this blog. This is because of my main job schedule is very tight, so I cannot even manage this blog at all. But thankfully I am still having my routine music listening session, probably a few hours a week, with the current audio setup is using the low cost AD1865NK DAC, the LM3875 Gainclone amplifier and SB-acoustic 2-way speaker system. For the digital player is iBasso DX-90 which I have used for very long time.

I am curious what is inside this tiny media player and I have an opportunity to open it up now.

Low Cost, Great Sound AD1865NK DAC Build

It started when I tidied up my storage bin on last weekends, I remember that I had an unused AD1865 DAC complete board from my previous DAC project. This board is okay, I think it performed quite well at that time, but I immediately replaced it with another DAC project because my curiosity is much faster than waiting 100 hours of capacitors break-in.

So here it is, an old AD1865 DAC board with new refinement and better calculation, using all parts I have in my bin. The building cost is nothing because all the new parts are already in my hands.

Miflex MKP-14 Capacitor for Speaker Cross-over Upgrade

Continue from my previous speaker cross-over modification from -12dB to -6dB slope, I satisfy with the result and I would replace the capacitor to the better one.

I had used many high-quality capacitor on my previous project and for this cross-over capacitor component, I will prefer to use Miflex MKP-14, which not only for it's affordable price, but in my opinion, the quality is better than Jantzen Cross-cap or Mundorf MKP.

Speaker Crossover Comparison -12dB Vs. -6dB Slope

We are fully aware that the speaker is the end of every audio chains. In my experience, once I get satisfy with a pair of speaker, then it will sit there for very long time. The reason is because every speaker has their own characteristic to match with the room acoustic and personal taste. This is not easy to having the right one, and of course with affordable price.

My speakers is the 2-way system, they are consisting of 2 drivers from my local brand, SB Acoustic SB16PFC25-8 for mid-bass and SB19ST-C0004 for tweeter. I've listening to this speaker for quite long time with the -12dB crossover point, or commonly known as 2nd order slope.

They are all good, but today I want to try the -6dB crossover point.

TDA1541A-S1 DAC & Pass D1 Analog Stages

Once again, I like to have another DAC using TDA1541, because all of my previous built TDA1541 DAC already sold like hot cakes.

Same story, I missed it.

Because any DAC using TDA1541 has the magic that always keep me back again, to experience the sound quality from this marvellous DAC IC.

Today DAC build is completely different. I start with multiple power supply for each ICs voltage required, total of them are 5 individual voltages using a toroidal transformer and an EI transformer. Then going to rectifier and filtered using capacitors-resistor-capacitors to passively reduce the voltage ripples. The 10 pieces voltage regulators are used to every voltage required by every ICs pin. The signal from digital receiver to DAC IC are asynchronous re-clocking using external thermal-controlled-oscillator, then the DAC current output is converted to voltage by Pass D1 original design.

The result from this design are marvellous.

Parasound DAC-2000 Ultra Review

I am a lucky person that having this Parasound DAC-2000 Ultra today. This model is the highest grade from Parasound DAC line-up in the 90's, which using the latest 20-bit DAC module from the Ultra-analog company.

The Ultra-analog DAC module itself is one of the best DAC and can only be found inside the highest-grade DAC like this. Ultra-analog module has different approach compared to the mainstream DAC manufacturer such as Burr-brown, Analog Device, or Philips. Unlike producing an IC die, this Ultra-analog DAC is producing a module that inside it are consist of many IC's from those popular manufacture as well.

I still believe the reason why this Ultra-analog DAC comes in module is because the engineering behind it knows how the good sound should be, so they combining many IC's to make this DAC module.

So here is the Parasound DAC-2000 Ultra review with Ultra-analog DAC module inside.