For years I have been trying to create a Media Center to attach my TV. I’ve tried Windows Media Center years ago, Myth TV on Linux, and everything in between. Nothing was simple, cheap, and easy to setup. I have friends who have tried those off the shelf media boxes like the ones from Netgear and the likes, but those have their pitfalls too. I wanted something open source, truly hackable, and preferably something Unix/Linux based. Thats why I turned to the Apple TV.

For my use case, I did not care about disk storage. I am using my Apple TV’s as terminals or endpoints to play media from storage somewhere else on the network. This allowed me to buy the cheap version of the Apple TV with a 40 GB drive for about $220. Not only that, there is a Toslink (optical) out that I will be attaching to a DAC and set of vintage tubes for crisp beautiful sound. For that kinda money, its pretty hard to beat the Apple TV.

Once in my possession, I immediately hacked it to expand its functionality. Without it, the Apple TV is actually pretty restricted and an overall weak product; however, Boxee helps make it all better. Boxee allows you to watch all those formats that iTunes does not support, like DivX, etc. Not only that, it allows you watch Hulu as well as other online video services.

Hacking your Apple TV and Installing Boxee

There’s actually nothing to do really and I would barely consider it hacking. A few folks out there have made it quite easy. In a nutshell, all you need to do is create a ‘patchstick’ on your PC using a thumb drive you have laying around. You insert it into your Apple TV’s USB drive, restart it, and voila! It installs itself and you’re all set. You can get the USB Patch Stick creator from the Google code repository.

Simply put, a basic vacuum tube is much like a light bulb. In a light bulb, negatively charged electrons travel through the filament colliding into the surrounding atoms but in a vacuum tube the electrons jump off the filament onto a positively charged plate called an anode. This type of vacuum tube is called a diode. What it does is convert AC to DC. This basic idea has been around since 1904 and later perfected in 1907. Since then many variations have come and gone but the same basic concept hasnt changed. The tube you see to the right is an RCA 5692 triode tube from the 1950’s. My newest amp requires three of them on the input side but more of that later.

Over the past 100 years they have appeared everywhere in world of science and technology. They were in televisions, radios, radar, tanks, phone networks, stereos, and really almost everywhere. They eventually became the backbone for the first computers. Today, most tubes have been replaced with much the much smaller and modern semiconductors we see today. Nowadays they are often found among radio enthusiasts, high-end or vintage stereos, and in guitar amps.

So whats so great about vacuum tubes in an amplifier?

It really depends on who you ask. This has been a long drawn and heavily debated issue ever since the first solid-state stereos were introduced in the 70’s. For me, I like all things vintage. Especially vintage technology. I love their simplicity, their nostalgic character, and the attention to detail you get from a hand built piece of equipment. For just the engineering reasons alone I love them. All that being said, they sound wonderful! They are warm and rich and deep. The sound can be so real and the stage so perfect that Neil Young’s harmonica sounds like its next to you and Stevie Nix is singing in your living room.

For me, its a really the entire experience; the charm and character that they bring along with a good piece of vinyl is amazing. The solid-state guys say that the sound isnt right due to the electron cloud inside the tube which is responsible for amplifying the sound. The analog guys claim its reality, its lifelike, and a lot of music was recorded this way since the beginning. Either way, I seem to enjoy them.

What is an RCA 5692 tube and more importantly, what is a triode?!

Lets not worry to much about the RCA tube you see above and look more at what a triode itself is. There were so many different ones built from so many countries over so many years it can be dizzying. All that really matters is that they are like cars. Some were well built and some were not.

To the left is a basic diagram of a triode vacuum tube (thank you Wikipedia). The main difference here between a diode and a triode is the grid surrounding the filament.

Remember that the filament is emitting negatively charged electrons that are picked up by the anode, but in a triode tube, there is a grid or screen in between. By applying a negative charge to this grid you can control the amount of electrons that will contact the anode.

There is a lot goes into the circuit topology the dictates how to charge the grid but thats another story for another day. The two amplifiers I currently have are both powered by triodes, both on the input and output side, but their design differs in the way the tubes are implemented.

A few months back I started sketching out plans for a do-it-yourself record player. Since then, not much has gone on due to my friend the electronics expert being out of town so I decided to source some parts. I turned to a Chinese company called diyhifisupply.com. China you say? Well, over the past few years China has really become a key player in the DIY world of high fidelity. They are creating high quality components a great prices from the platter you see below to oil filled caps, tubes, and other various parts.



This platter was laser cut out of 40mm thick acrylic at a final diameter of 298mm. Its truly is a beautiful piece of work. The markings on the platter are for timing it with a strobe. Below is a photo of the bearing that I ordered along with it. It too is a very nicely machined piece of work with a self-oiling design using rifles to push the oil back up to the bearing. When everything is all connected together it turns very smoothly.

For a long time now I have been interested in vacuum tubes. I love their simplicity, sound, and the fact that the design hasnt changed since the early 1900’s. They also were used as transistors in early computers before the solid state transistor was invented. 50 years ago it would take an entire room of these to power a computer with less memory than a Casio wristwatch.


Anyway, this is a beautifully hand made oil-filled-cap integrated amplifier than runs in 80-watt Class A/B ultra-linear mode and 40-watt triode mode. I have it fitted with a set of Russian Electro-Harmonix tubes, the power coming from two sets of KT88’s. The sound is quite crisp with little to no hum or background noise which is surprising considering tubes are known for these issues. This paired with a set of Kef iQ5 floor standing speakers are wonderfully crisp and clean, especially with vocals. Now, to fix the weak link, the 5 dollar garage-sale bought record player. More to come on the DIY record player later.