Bottlehead Crack W/speedball

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Bottlehead Crack OtlBottlehead Crack W/speedball

I’m going to guess that the Crack is Bottlehead’s all time most popular kit. A great little tube headphone amplifier at a price-point nearly anyone can afford that sounds very good for the money, it’s really hard to go wrong here. The Crack has gone up in price a little bit since its introduction 3+ years ago, but it’s still quite a value. I also highly recommend the Speedball upgrade, which replaces the plate loads on the tubes with a constant current source and brings this amp into its own with added detail and transparency.

I shortly after its release and of course replaced a number of the parts with racier versions and it sounded quite good. Years later, I reminisced how much fun it was to put together that point-to-point Crack and decided to build a new one from the ground up with fancy parts and give it a layout that would accept that added girth. While I normally would have turned to to shape me up a new chassis, it was time for me to step up and build my own, despite not being crazy about working with wood. The first task was to figure out what the size of the top plate would be with the additional room for larger capacitors (in both coupling and power supply positions) and a pair of large-ish Hammond chokes for the power supply as well. This ended up being 12” x 12” (more than twice the stock 10x6 size!), which is perfect as sheets of metal can be ordered in 12” x 12”.

Rather than go with the typical aluminum plate, I spent a few extra bucks and went with a 12” x 12” x 0.1” copper plate. The copper provides even better grounding and conduction than aluminum and comes with a nice natural color. Despite the fluctuating metal market, a copper plate this size isn't too bad at about $40. The next chassis-related task was to create the wooden box that the plate would sit on top of. This is not the most trivial of tasks for those of us not blessed with nice power tools and a garage. Rpg Maker Xp Product Key Generator Download.

What yields an even more intense experience than Crack? The most hardcore users say it’s a Speedball. Speedball is our Camille Cascode Constant Current Source. **How difficult is this to build?** >I have a fair amount of soldering experience, having modified several mechanical keyboards. Bottlehead crack for sale. Bottlehead Crack Headphone Amp just completed July 2016, with Speedball upgrade. This amp was purpose built for sale and is NEW condition. Bottlehead Crack for sale. Bottlehead Crack OTL Tube Amplifier for headphones with Speedball upgrade and tweaks to let certain tubes work. Comes with 4 tubes.

So, I drew up the dimensions of the plate, where the plate would sit on top of the routed edges on the wood, noted how deep the route would be, and based on that drawing I found the appropriate sizes for the wood to be cut and added about a 1/16” of an inch for wiggle room. For the wood itself, I decided I wanted something a little more intricate (“fussy”, as someone I know would call it) than flat sides, so I went with a flat piece of pine and a piece of decorative molding and glued the two together. I then used the router to make a decorative route along the outer top edge and used a rabbeting bit to make the inner route that the plate would sit on.

Four sections of this piece could then be cut at 45 degree angles to make the box. Since I was cutting the wood by hand, I used a plastic miter box and did my best to cut at a straight 45 degrees all the way down to get the corners to line up properly. Obviously, this never works out perfectly, so that’s what wood filler is for. Once the box was assembled with wood glue and the wood filler sanded down smoothly, four small wood blocks were glued to the bottom corners to provide adequate surface area for the EAR damping feet to be placed. For the finish, rather than simply staining the wood like I normally would, I opted to use a copper leafing kit from Old World Art to bring the copper theme into the base. The leafing kit is a multi-step process including a red base coat, adhesive size layer, application and burnishing of the metal leaf, a sealer coat, application of an antique top-coat, and then another sealer coat. The nice thing about copper leaf is it's incredibly cheap; a set of 25 sheets runs less than $10.