Built around a fully-discrete R2R ladder, the Druid converts digital data into analog waveforms through a precise network of resistors rather than a high-speed modulation process. Each resistor contributes a tiny part of the signal, forming a sound that feels natural, human, and grounded in something older than silicon. This DAC does not compute. It communes. 

The idea came straight from the community: give the upcoming R2R DAC swappable op-amps. What started as a suggestion turned into one of our favorite parts of the Druid. The open-chassis design made perfect sense for it: no case to crack open, no hidden screws, just clear access to the sockets. We’re glad the community pushed us on this one, because it made the Druid into an even more satisfying product. Need help swapping op-amps?

Note: Given the Druid's compact design, no single op-amp may draw more than 10mA. Exceeding this risks overheating, unwanted noise, or potential damage to the unit.

Inside are three swappable op-amps: two for the balanced XLR outputs and one for the single-ended 3.5mm. When it came to choosing the stock op-amps, we didn't start with any particular sound or spec sheet advantage in mind—just a price point and the goal of being wowed. We tested everything we could get our hands on, and the Texas Instruments LM4562NA/NOPB stood out immediately. It handled the midrange with an easy, natural smoothness that made vocals and acoustic instruments feel alive. Especially paired with the Gremlin, it brought a smile to our faces. 

For those running balanced chains, the Druid provides a 4V XLR output that delivers all the current and control you’d expect from a fully differential stage. The result is lower noise, higher headroom, and tighter channel separation: everything you want when driving balanced amplifiers or powered monitors. 

Because PCB space is sacred, the Druid uses a 3.5mm line out instead of dual RCA jacks. A 3.5mm-to-RCA adapter is included in the box, letting you run the Druid into any single-ended amplifier or powered speaker chain. 

At the heart of the Druid’s digital stage is the XMOS XU316, one of the most capable USB controller chips available today. It handles data transfer with rock-solid stability and ultra-low latency, ensuring every bit arrives exactly as intended. With sixteen cores running in parallel, it keeps high-resolution audio streams (PCM 768kHz, DSD512) moving effortlessly, without adding timing errors or background noise.

Add the Stacker to your order if you plan on using the Druid R2R with the Gremlin amp. This translucent acrylic platform lets you stack the two together like a proper adventuring party. It's precision-cut to cradle the Gremlin's lower acrylic plate and keep it snugly perched without adhesive or screws. Our very own Sean Flynn designed the stacker, and our buddies at Salad made it a reality. We’ve priced it to be a no-profit product—the price you pay simply covers our costs. But we’d like to keep the DIY community ethos going, so we’re working with Salad to make it an open-source download on GitHub. Print it, tweak it, remix. If you come up with something great, send it our way at communityfeedback@apos.audio so we can show it off. 

• R2R ladder DAC

• Fully swappable op-amps with included lifts and puller

• Balanced XLR outputs and 3.5mm line output

• RCA compatible: 3.5mm line out to RCA adapter included

• XMOS XU316 USB interface

• External power brick–style adapter with dedicated ground wire for cleaner, quieter performance

• Smooth, mid-focused LM4562NA op-amps installed

• Compact aluminum and acrylic chassis, desktop-friendly design

• Underside LEDs with on/off jumper switch

• Need help swapping op-amps?

• DAC architecture: Fully discrete R2R resistor ladder

• Op-amps: Three swappable Texas Instruments LM4562NA/NOPB (two for balanced XLR, one for single-ended 3.5mm)

• Note: Given the Druid's compact design, no single op-amp may draw more than 10mA. Exceeding this risks overheating, unwanted noise, or potential damage to the unit.

• Op-amp support: Standard DIP-8 sockets, includes three lifts and puller tool

• Outputs:

  • Balanced XLR (4V RMS)

  • Single-ended 3.5mm line out (adapter to dual RCA included)

• Frequency response: 20Hz-20KHz (+/- 0.5dB)

• Signal to noise ratio: 90dB

• Minimum distortion: 0.04% (1KHz)

• Separation degree: 82dB (1KHz)

• Digital inputs: USB Type-C (XMOS XU316 controller)

• Supported formats: PCM up to 768kHz / 32-bit, DSD512 (native)

• Power supply: 12v external brick-style adapter with dedicated ground wire

• Lighting: Underside LEDs with on/off jumper switch on PCB

• 1x Druid R2R DAC

• 3x LM4562NA/NOPB op-amps (installed)

• 3x op-amp lifts

• 1x op-amp puller tool (black)

• 1x power adapter

• 1x manual

• 1x 3.5mm to RCA adapter

AN APOS 𝒙 PRODUCT

Apos 𝒙 is the next generation of grassroots products. It bridges designers, manufacturers, and the community to turn ideas and feedback into unique creations. By involving the community at every stage and supporting designers, Apos 𝒙 ensures that products reflect the desires and creativity of their users. Participate today. 

APOS 𝒙 CREDITS

Community Participants

These professionals and community reviewers gave us early feedback that helped refine the final version of the product. If you’d like to participate in future launches, fill out our form. 

Andy Cook

Michael Johnson

Gordon Cooper

Apos Team

Tom Mounce

John Soriano 

Kunal Kumar

Sean Flynn

Thomas Fernandez

Peter Carelli

Alex Peterkin

Steven Hortizano

FAQ

Q: Can you run both the Merlin DAC and Druid R2R DAC to the Gremlin Amp at the same time? 

A: No. Due to the input/output layouts of the three units, either the Merlin or the Druid can be connected to the Gremlin Amp at one time. 

Q: How do I swap op-amps? 

A: Check out the video to the left or our blog post.