Speedball 1.1 Upgrade for Crack Amplifier


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 upgrade for the Crack headphone amplifier. The 22.1KΩ plate loads of the 12AU7 input triodes are replaced by C4S loads, as are the 3KΩ cathode load resistors of the 6080 triodes. The PC board for the loads on the 6080 tube has very ample heat sinks to assure high reliability. The same Speedball 1.1 kit is an upgrade for Crack 1.1 and the original Crack.

If you are buying this upgrade at the same time as your Crack 1.1, please select it from “Upgrade Options” menu on the Crack 1.1 page. Do not order it from this page.

It typically takes anywhere from a day to a couple of weeks to get your kit ready to ship.



Quick Description

We consider this a skill level 2 kit, meaning that it is intended for someone who has construction of a kit under their belt (like the basic Crack kit). The new skills you might acquire will be those of stuffing and soldering a PC board, and removing a few components to allow installation of the upgrade. Assembly and installation is an easy one evening session, requiring only the removal of four resistors from the previously assembled Crack kit. 


So what does it do for the sound? The most immediate thing you will notice is a better sense of clarity. Things get tighter and quicker, bass and midrange get cleaner and more dynamic sounding, and the background gets more quiet. As with all of our upgrade kits, the improvement is easily heard.


Heart of England Crack – to go with the geographical naming theme, here’s my completed Crack from Northamptonshire England. It’s my first BH project, many thanks to Doc and the gang for an awesome kit, and members on the forum for inspiration on the upgrades (especially Mr. Davis’ Puget Sound Crack for the Axon caps idea). I use it with my DT770 600ohm, and it sounds superb. Totally black background, really deft mids and highs, and it pushes just the right amount of well-controlled bass into the 770s, which can be a bit bass-light, even with a solid amp. Case in point; to my ears, it sounds better into these ‘phones than my Schiit Lyr. –gh0st on the Bottlehead Forum

WOW! thought it was silent before… it is dead quiet, and insanely resolving…doc, this thing is SICK at this price point!!! –c_hatfield on the Bottlehead Forum

Guys, Grab the Speedball upgrade too. I listened for 6 hrs straight after I got it installed, a real good sign that something is sounding very right! –Todd R, on Head-fi.org

I rec’d my built Crack with the Speedball upgrade and I’m really impressed with the sound. My T1s sound GREAT with it, it drives them with no problem at all. –Canuck57, on Head-fi.org

Wow! Speedball! –grufti, on the Bottlehead Forum

Yes, WOW Speedball. I used to feel that my Enhanced Sex/Hammer Dynamics speaker setup was a more involving listening experience, but now with the speedball upgrade the Crack /DT770(600 ohm) combo comes much closer to being in the “listening room”. –nsorens, on the Bottlehead Forum

I have taken possession of the Crack w/Speedball prototype and I will not be relinquishing it any time soon. I love it even more than when I first heard it @ CanJam, dropped now into my humble little system. Fed by a netbook running Ubuntu/Amarok & an Audinst DAC driving my Beyerdynamic DT990 600 ohm cans with a sweetness. –Levlhed, on the Bottlehead Forum  

Additional information

Weight 0.75 lbs
Dimensions 6 × 6 × 3 in

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