Amp Camp Amp and GR-Research X-LS Encore speeakers DIY Project

[Puma Cat]

As there is no DIY Audio forum, I'm posting this here...

I'm building up a pair of the Amp Camp amps (ACA), which are a full Class A amplifier designed by Nelson Pass. These come as a kit for $327, including all parts, the heat sinks and chassis, and can be used as a stereo amp or bridged or paralleled monoblocks. I bought two and will be configuring them to run as bridged monoblocks. They will put out about 15 W of Class A power into 8 ohms in bridged mode. I completed all the boards this weekend and have started putting the chassis and connectors together.

Here are some pics of my ACA 18 "Premium" Parts build. This is subsituting some of the stock components with more premium parts and changing a few resistor values. This my first build since I built my Hafler DH-101 more years ago than I care to remember...

Photos from my wondrous little Fujifilm X100F, shot with available light and/or TTL fill. Even the base kit uses really nice parts, e.g., Vishay metal film resistors and Elna capacitors, but I've upgraded some of the caps with a Nichicon Gold Tune cap at C1 and the aluminum organic polymer Nichicon caps at C2 and C4 that comprise part of the premium parts build.

The boards for each channel or "half", depending on the configuration.






Close-up of one fo the boards; here R4 is run parallel with another resistor to lower the resistance in this part of the circuit to optimize current to the transistors.



The rear panel with information on how to make connections and setting to run in different output configurations. One can use the amp in stereo or as a monoblock simply by using the switch at the top of the rear panel.




I'll post more pics of the amps as I progress with finishing the build.

The speakers I am planning on using with the ACAs are the X-LS Encores designed by Danny Richie of GR-Research in Texas. These are also sold as a DIY kit for a whopping $249 for the base configuration.

The X-LS Encores are 87 dB/1W-m sensitivity which should be fine as I typically listen at levels 68-72 dB when sitting 7 ft in front of the speakers in my small listening space. They have a nominal impedance of 8 ohms.



My cabinets were built up by one of Danny's employees, who is also a woodworker. He's veneered them for me and stained and oiled the cabinets.

Here's a pic of my cabinets...



Once I receive the cabinets and speaker components, I'll wire up the crossover, connect and mount the drivers, and assemble the parts into a finished loudspeaker.

More pics to follow on this project, so stay tuned...

[CGabriel]

Looks like a lot of fun PumaCat!

[Puma Cat]

Originally Posted by CGabriel

Looks like a lot off fun PumaCat!

Thanks, Caelin.

Yeah, it's proving to be a lot of fun.

[Antonmb]

Looks pretty cool Stephen, I’ll be interested to see your progress on the amps.

[crwilli]

Fun stuff Stephen!

[Puma Cat]

Originally Posted by Antonmb

Looks pretty cool Stephen, I’ll be interested to see your progress on the amps.

Thanks, Tony.

[Puma Cat]

Originally Posted by crwilli

Fun stuff Stephen!

Thanks, Craig.

[Puma Cat]

Tonight I mocked up the chassis and boards assembled to determine the length of the hookup wires required from the boards and switches to the rear panel. Because the boards are "asymmetric" with respect to their positions on each heat sink, I wanted the wire lengths for the respective connections to the boards and each amp to be identical, so this was the best way to do it.

[audioguy3107]

Stephen, that looks like a really cool project! The speakers look great too. Looking forward to the finished project.

- Buck

[Puma Cat]

Originally Posted by audioguy3107

Stephen, that looks like a really cool project! The speakers look great too. Looking forward to the finished project.

- Buck

Thanks, Buck. Will be posting more pics as the build progresses.