Installed Speedball.įrom my experience, this is unquestionably a worthwhile upgrade. “It puts a very high (several Megaohms) impedance load on the plate of the gain stage and the cathode of the follower stage… Two small Camille Cascode Constant Current Sources are installed in place of the plate load resistors on the 12AU7 input triodes, and two big and beefy ones complete with heatsinks are installed in place of the cathode load resistors of the 6080 triodes.” – Doc Bīottlehead states that “the improvement is easily heard” and makes the Crack “quicker, more quiet, better mids, better bass, better resolution.” In more technical terms, the constant current improves isolation of the power supply by about 60dB and keeps the tube in a more linear operating state as it approaches clipping. Note the unified board and revised components.īottlehead lists the Speedball as a Camille Cascode Constant Current Source (C4S) design, originally created by the late John Camille (known as Buddha in audio circuit design circles). Again, a full set of excellent instructions is included to guide you along. It does require removing 4 resistors from the stock Crack to install.
Bottlehead crack w speedball install#
It should only take you a few hours to complete and install a Speedball. The process of “stuffing” and soldering a circuit board isn’t difficult, but it is smaller scale and fussier than the Crack assembly. Speedball v1.īottlehead considers this a level 2 kit, meaning it is intended for someone who has some experience and already completed a kit (like the Crack). This is a much neater and elegant solution than the multiple board version 1 implementation that I have in my own Crack. The most recent version (v1.1) consists of two circuit boards, associated components, wires, standoffs, and screws. The place to start your upgrade journey is with Bottlehead’s own Speedball kit. Other Modifications (not recommended by Doc B).Bottlehead Speedball – Camille Cascode Constant Current Source (C4S).Just try to keep it sane ).”īasic modifications can be broken down into a few categories: There’s lots of great $15 caps and $30 pots out there that can improve the resolution, and tube rolling can be a lot of fun too.
Bottlehead crack w speedball mod#
“don’t get me wrong, I love that folks mod our kits! Appropriately priced parts can be great fun.