As mentioned a couple of weeks ago, find herewith the Desktop version of my Pimeta v2 amp with the following features:
- Integrated power supply with the r1 regulator - 25V DC
- Selectable 3 line Input and 3 lines Output
- Integrated modified Linkwitz Crossfeed circuit
- Integrated Bass Boost (pot) and Volume Boost (switch) circuit
Here a few pics:
The main boards (Pimeta v2, Linkwitz Crossfeed and r1 regulator) assembled and ready for installation.
As a support, I've chosen an acrylic plate that I can slide into the Hammond enclosure. Bottom-left see a little board for the power cabling, while on the top-right side the micro-switches have been mounted on another little board.
From the bottom, with the I/O connectors and the back panel.
These little boards are used as indicators on the front panel for the selected I/O lines - the selectors are on the back panel.
Here the Bass and Volume Boost board - it has taken me a while to get the components for the best audio experience - that can be mounted as piggy-back directly onto the Pimeta v2 board.
Lastly, another little board that mounts the Bass Boost pot and an LED supposed to indicate the operation mode (Headphone = green, Preamp = red).
Here from the bottom, pretty much ready to be put into the enclosure.
Same from the top, all modules are plugged-in and the amp has undergone all tests.
Sliding it into the enclosure, there is not much room left for other stuff. I've tried to isolate the toroid transformer (german manufacturer, high quality) as good as possible, and luckily there is no electric or magnetic interference.
Here the finished product - front and back view. Note the holes that I had to drill in the cover to allow some airflow - a bit of an artistic touch with the 4 inside LEDs spreading rays of blue light.
Here another view of the two units I've built.
My objective was to have a modular design with all the features I needed to have. In order to eliminate the hum, I had however to ground the IG to the case. Else everything worked as per plan, exception made for the 'Preamp' mode of operation that is miserably poor...