Skip to content
View in the app

A better way to browse. Learn more.

www.Head-Case.org

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Leaderboard

Popular Content

Showing content with the highest reputation on 08/10/26 in Posts

  1. ^ On that note, The Ultimate Bill Evans As Selected By Herbie Hancock, which seems in Japan to be titled To Bill Evans With Love – Selected By Herbie Hancock on SCM-CD.
  2. Logged some hot miles this afternoon riding to York, ME. Feels like temp was 93F and it felt every bit of that. Thank god for a little tail wind.
  3. 1 point
    It's like seeing a Bentley parked in a trailer's car port.
  4. I think it must be something with iPadOS or Firefox. I’ll try later on another browser or computer, if it doesn’t work I’ll tell you.
  5. If it annoys you too much, let me know what you want to donate and I'll do it in your name. Thanks for kicking off the party, Mikey and Todd! I'm going to ride up to the Maine coast this afternoon for a friend's 50th and it's a scorcher! It's 9AM and it's already 80 in the shade. Good thing the ride will end at the beach.
  6. Also a little clarity on my side. I go back longer with Coltrane, but listening to a ton of nearly every period of Evans lately. Most importantly I’m currently reading the below (which so far has been great) so we’ll see where I end up.
  7. Both the power supply and amplifier chassis are approximately 290 mm × 400 mm × 90 mm, so it's actually fairly compact considering it's a full-size T2. The power supply uses five GRHV regulators and features plug-in bias daughter boards, making it easy to switch between different bias voltages. Right now it supports both Normal Bias and Pro Bias outputs. The PSU also includes about a 50sec high volt soft start. In addition, there's an AC inrush limiter on the mains input. After roughly one second, a relay bypasses the current-limiting resistor, reducing the inrush current seen by both the filter capacitors and the tube heaters during startup. On the amplifier side, most of the passive components are SMD, which helped reduce the overall PCB and chassis size. The amplifier topology stays very close to Kevin's original T2 schematic, but I added support for several different implementation options to make the design more flexible. It supports three different CCS configurations:10M90, 10M90S + DN2540, and the original T2 complex CCS. The active battery section is also configurable. It supports: LED string reference, LT1021 reference. For the 2SK216 and 2SJ79 positions, I added an extra pin so they can be replaced directly with TTC and TTA devices without modifying the PCB. The overall goal wasn't to redesign the T2, but rather to preserve the original circuit while making it easier to build, maintain, and adapt as some of the original parts become increasingly difficult to source. The chassis is CNC machined by a local machine shop. One detail I paid particular attention to was the top cover of the amplifier chassis. I designed it so that the EL34 tube sockets sit perfectly flush with the top panel, which I think gives the amplifier a much cleaner appearance. Additional ventilation slots were added in the center section for airflow. The side heatsinks are sandwiched between the top and bottom panels. This not only gives the chassis a cleaner look and prevents the sharp heatsink fins from being exposed, but also makes it much less likely that you'll scratch your hands when moving the amplifier. To make sure the heatsinks can still dissipate heat efficiently, I also added ventilation openings in the top and bottom panels wherever they cover the heatsinks. I've also been thinking about turning this project into a group buy, although I'm not sure how much interest in the T2 still exists today. The main motivation would be to reduce the chassis cost, since having a single custom CNC chassis made is quite expensive. If enough people were interested, the machining cost could come down significantly.
  8. After about a year of work, I've finally finished redesigning the PCB layout for the original T2. The new layout supports several different active battery implementations, as well as multiple CCS options, making it much more flexible for different builds and future experimentation. I've also completely redesigned the chassis. Like the original concept, it will still use a two-chassis configuration, with the power supply and amplifier housed separately. It's been a long project, but it's exciting to finally see it coming together. I'll share more photos and progress updates as the build moves forward.

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.