A popular Bottlehead Crack mod is changing the electrolytic output capacitors with huge film capacitors. The Crack is born with a pretty decent pair of output caps, so why do change them at all? Because it looks darn cool! Nuff said, let get going.
When I ordered my Bottlehead Crack kit, I also ordered the Speedball upgrade right away. Everybody that tried it, including reviews, said it was a night and day difference from the default Crack setup, and that you basically had to upgrade it. So of course I wanted to hear that for myself. Bottlehead recommends building the default Crack and make sure it works properly before moving on to the Speedball upgrade, so this is why I have done so.
In the late 80s and early 90s, virtual reality was one of the most promising upcoming new technologies. There was a promise of amazing experiences in exhilarating virtual worlds, and consumers were more than ready for adventures that would blur the border between game and reality. Even the film industry was interested in the idea, which led to cult classics such as The Lawnmower Man and Johnny Mnemonic.
The Bottlehead Crack is not made on a printed circuit board like modern amplifiers. Instead all the parts are mounted and soldered on terminal strips and connected with solid core wires between the components. If done properly with good soldering skills and quality wires, this is a very good way of making circuits for amplifiers. It’s also a way of using three dimensions, instead of the two dimensions you are often restricted to with circuit boards. Another obvious advantage is more space between components, wires and interconnects, causing less interference…
O2 or Objective2 is an open source headphone amplifier designed by the brilliant and shy engineer NwAvGuy. His purpose was to design an objective sounding headphone amplifier at relative low cost, that could compare to the most expensive neutral headphone amplifier made. He also made sure to make a design with the lowest possible input impedance, hence making it a good fit for any set of headphones, regardless of impedance. He claimed that nobody would be able to hear the difference in a blind test, compared to any neutral sounding headphone amplifier,…
The KODA^2 – Optimizing the prototype Since I made the prototype – I have done some optimizing of the design. It still looks the same on the outsize – but inside has been optimized with the correct sized bass port and 20% less material in overall. This makes them lighter and gives them just the right bass port directly from the laser cutting process. I feel that the weight of the KODA^1 is their only real downside and the new optimized design should issue this and make them below…
Oculus Rift Crystal Cove – CES 2014 (1080p AMOLED). Picture: Polygon.com Since I my review of the Oculus Rift development kit, Oculus Rift has demonstrated another awesome prototype that deals with problems I didn’t expect anyone to solve this soon. The prototype is called Crystal Cove and 1080p AMOLED (ultra fast) Low persistence 6 DOF tracking via camera Much less latency overall Low Persistence With low persistence Oculus VR and Valve has solved one of the biggest issues with the current development kit or actually with VR googles in general….
You often hear people describe their first encounter with Oculus Rift as an almost life-changing experience, or at least a true next-gen experience. There are countless videos on YouTube with people testing Oculus Rift, with their jaws hanging down their chest, or just screaming like a little girl while trying the Rift Roller Coaster. It’s hard not to jump aboard the hype train when watching these videos and reading all positive things said about Oculus Rift.
This is the second part of the Bottlehead Crack build. It’s time to place all the parts on the freshly painted chassis and prepare for the final assembly of the amplifier. This part is just the preparation of the chassis before soldering the part on the terminals,tube sockets and power transformer. From here on, it’s all about the circuits and electronics.
This is the first part of the Bottlehead Crack build. In the following parts I will show how I made my Bottlehead Crack amplifier and maybe even give you some inspiration for your own DIY projects. Bottlehead Crack is an OTL tube amplifier for high impedance headphones. OTL means that it’s an Output Transformer less design. The output transformer in a tube amplifier causes a lot of distortion because it’s located directly in the signal path.