Image 1 — 𝗦𝗝𝗬 𝗔𝗥𝗚𝗢𝗦 𝗮𝗻𝗱 𝗔𝗽𝗼𝘀 𝘅 𝗘𝗦 𝗟𝗔𝗕 𝗛𝗬𝗗𝗥𝗔 — 𝗘𝗹𝗲𝗰𝘁𝗿𝗼𝘀𝘁𝗮𝘁𝗶𝗰 𝗛𝗶-𝗙𝗶
Image 2 — 𝗦𝗝𝗬 𝗔𝗥𝗚𝗢𝗦 𝗮𝗻𝗱 𝗔𝗽𝗼𝘀 𝘅 𝗘𝗦 𝗟𝗔𝗕 𝗛𝗬𝗗𝗥𝗔 — 𝗘𝗹𝗲𝗰𝘁𝗿𝗼𝘀𝘁𝗮𝘁𝗶𝗰 𝗛𝗶-𝗙𝗶
Image 3 — 𝗦𝗝𝗬 𝗔𝗥𝗚𝗢𝗦 𝗮𝗻𝗱 𝗔𝗽𝗼𝘀 𝘅 𝗘𝗦 𝗟𝗔𝗕 𝗛𝗬𝗗𝗥𝗔 — 𝗘𝗹𝗲𝗰𝘁𝗿𝗼𝘀𝘁𝗮𝘁𝗶𝗰 𝗛𝗶-𝗙𝗶

𝗦𝗝𝗬 𝗔𝗥𝗚𝗢𝗦 𝗮𝗻𝗱 𝗔𝗽𝗼𝘀 𝘅 𝗘𝗦 𝗟𝗔𝗕 𝗛𝗬𝗗𝗥𝗔 — 𝗘𝗹𝗲𝗰𝘁𝗿𝗼𝘀𝘁𝗮𝘁𝗶𝗰 𝗛𝗶-𝗙𝗶

Today we’re introducing the SJY ARGOS Electrostatic Headphones and Apos x ES LAB HYDRA Integrated Amplifier, two new products inspired by Japan’s electrostatic golden age.

The HYDRA is one amplifier for nearly everything. It combines a 580V electrostatic energizer with a Class AB amplifier delivering 20W per channel into 8Ω, powering electrostatics, planars, dynamics, and passive speakers from one many-headed machine.

The ARGOS, named after the all-seeing Argos Panoptes of mythology, pairs a 580V pro-bias electrostatic driver with a natural, slightly warm tuning. Expect the speed, separation, imaging, and fine detail electrostatics are known for, with more body in the bass and more presence through the vocals.

Explore the Electrostatic Collection at Apos.

u/aposaudio — 1 day ago

Matrix Audio SI-1 Network Isolator

The SI-1 sits between your network switch or router and a network audio component, providing active optical-electrical isolation across the Ethernet connection.

It uses independent optical transmit and receive channels, dual femtosecond clocks, and a linear power supply with a dual-winding potted toroidal transformer. The isolated output supports Gigabit Ethernet, while the electrical separation also helps address ground-loop and network-borne interference issues.

It’s a fairly specialized piece of network hardware, but the design is aimed squarely at systems where electrical isolation is worth pursuing.

Check the details of the Matrix Audio SI-1 at Apos.

u/aposaudio — 5 days ago

[Group Buy] GMK CYL Hyperfuse Origins — Last Day

Today is the final day to join the GMK CYL Hyperfuse Origins Group Buy.

This release brings back the classic gray, cyan, and purple Hyperfuse colorway in GMK’s CYL sculpted profile, with doubleshot ABS construction and the familiar 1-1-2-3-4-4 row sculpting.

The set is available as separate Base, Numpad, and Unusual Kits. The Numpad and Unusual kits also include select south-facing LED indicator keys.

Select orders will be randomly chosen to receive an Apos-exclusive Hyperfuse Artisan by Omniclectic.

The Group Buy closes today if you’ve been considering a set.

u/aposaudio — 6 days ago

Apos x OLKB Preonic Rev 4 Ortholinear Keyboard — Group Buy Now Live

The Preonic Rev 4 updates one of the best-known ortholinear keyboards without changing what made it popular. You still get the compact grid layout, but with a dedicated number row that makes daily use more practical.

This revision includes a ground-up PCB redesign with per-key RGB, integrated underglow, support for up to ten rotary encoders, an RP2040 microcontroller, and full QMK compatibility. The hotswap PCB also supports multiple layout options, so there's plenty of flexibility if you like experimenting with switches or key configurations.

If you've been waiting for the latest Preonic, the Group Buy is now open.

u/aposaudio — 7 days ago

FiiO IMP XLR-4 Power Amplifier Impedance Adapter

The FiiO IMP XLR-4 is designed to run compatible headphones from a home HiFi power amplifier. An internal voltage divider attenuates the amplifier’s output and helps reduce background noise before the signal reaches the headphones.

It supports 16–300Ω headphones and compatible amplifiers below 300W. Outputs include both 4.4 mm and 4-pin XLR balanced connections, with 4 mm banana jack inputs for the amplifier.

Check out the FiiO IMP XLR-4 at Apos.

u/aposaudio — 8 days ago

FiiO EA13 — 28W Class-A Stereo Tube Power Amp

FiiO has moved into full-size tube amplification with the EA13, a pure Class-A push-pull design using two SYLVANIA NOS PCF80 preamp tubes and four JJ ELECTRONIC EL34 power tubes.

Speaker output is rated at up to 28W + 28W into 4Ω or 8Ω, with at least 18W + 18W at THD+N below 1%. The amp uses custom EI output transformers and separate speaker terminals for both impedances.

Connectivity is straightforward — four RCA inputs, a 6.35mm headphone output, and a 12V trigger input. There’s also a 40-step analog volume control and mechanical VU meters, because apparently a tube amp still needs something to look at while it warms up.

The EA13 comes in black or silver.

More details and specs here.

u/aposaudio — 9 days ago

Now Available: GMK Jukebox MTNU Keycap Set

If you've been waiting for another MTNU release, the GMK Jukebox is now available at Apos.

Designed by livingspeedbump, the set takes its cues from 1950s typewriters, diners, and automotive colors. It uses GMK's sculpted MTNU profile with textured cylindrical key surfaces and double-shot PBT construction, while remaining compatible with MX-style switch stems.

Designed and manufactured in Germany.

Available now at Apos.

u/aposaudio — 13 days ago

Now Available: NITSCH x Schiit Magni Piety – Brass Knob Limited Edition

The Magni Piety is back in a limited Brass Knob edition.

Originally based on an experimental Schiit prototype, the Piety takes a different path from most modern solid-state headphone amps. Rather than chasing the lowest possible THD, its fully discrete Continuity-based design was intentionally tuned with distortion characteristics and gain behavior that are closer to tube amplifiers.

A few highlights:

  • Fully discrete, massively paralleled transistor output stage
  • New variation of the Continuity circuit
  • Limited edition solid brass volume knob
  • Two-step gain switch (1.8x / 6.3x)
  • Up to 1W into 32Ω
  • Output impedance below 0.6Ω
  • Hand-assembled in California

If you've been curious about the Piety but missed earlier runs, this version is now available at Apos.

u/aposaudio — 14 days ago

[New] Cayin CP6 — Portable CD player with selectable tube and solid-state timbres

The Cayin CP6 is a portable CD player, USB DAC, digital transport, Bluetooth transceiver, and fully balanced headphone amp in one chassis.

Instead of treating the tube stage as a fixed feature, the CP6 gives you three playback modes:

  • Classic Tube — warmer, smoother presentation
  • Modern Tube — more space and detail while keeping tube character
  • Solid-State — clean, neutral signal path

The hardware includes matched Raytheon JAN6418 NOS tubes, dual Cirrus Logic CS4308P DACs running in mono mode, selectable Class A or Class AB amplification, and up to 1300 mW + 1300 mW from the 4.4 mm balanced output when powered by DC.

Other features include:

  • USB DAC with XMOS XU316
  • Bluetooth 5.4 RX/TX with LDAC receive support
  • Lossless CD ripping to FAT32 storage
  • Coaxial and optical digital outputs
  • 7300 mAh battery with up to 7.5 hours of playback

For anyone who still buys CDs but also listens through desktop gear or wireless headphones, it's a flexible all-in-one player rather than a dedicated portable CD deck.

u/aposaudio — 15 days ago

Now Available: xDuoo MT-02 Hybrid Tube Headphone Amplifier

The xDuoo MT-02 is a desktop hybrid headphone amplifier built around dual 6J1 tubes feeding a transistor-based Class-A output stage. It delivers up to 1,500mW into 32Ω, with enough current to handle a broad range of headphones while keeping the presentation smooth and controlled.

Notable features include:

  • Dual 6J1 vacuum tubes
  • Class-A transistor output stage
  • Up to 1,500mW @ 32Ω
  • 4.4mm balanced and 6.35mm headphone outputs
  • High and low gain settings
  • Pre-out for powered speakers or external amplifiers
  • 30-second startup protection relay
  • ELNA and Rubycon capacitors
  • Aluminum chassis with transparent acrylic side panels

If you've been looking for a compact tube hybrid that also works as a desktop preamp, the MT-02 checks a lot of practical boxes.

Available now at Apos.

u/aposaudio — 16 days ago

Apos will be at HiFiCon Audio Meet on Aug. 1 — stop by if you're attending

If you're heading to HiFiCon on Saturday, come find the Apos table. We'll have a mix of production gear, community projects, and a few things that aren't publicly available yet.

We'll be bringing:

  • Apos x ES LAB Hydra Integrated Amp
  • Apos x SJY Argos Electrostatic Headphones
  • Apos x Community K1K Earspeakers
  • Apos x Elsewise Audio Zenfones Modular Planar Magnetic Headphones
  • Apos x Capra Audio IBEX Open-Back Headphones
  • Apos x Passion for Sound Lydian Desktop Amp
  • Prototype Desktop Analog Equalizer
  • Archive Tubes (selection)
  • Apos x Community Gremlin Desktop Amp
  • Apos x Geshelli Merlin Desktop DAC
  • Apos x Community Druid R2R Desktop DAC
  • Apos x Community Rock Lobster IEMs
  • Apos x Audio-Technica R70x Refine Headphones

If there's something on the list you've been wanting to hear—or if you just want to talk audio—stop by and say hello. We'd be glad to meet you.

Event Details

  • Hosted by: theBayAudioEnclave
  • Location: Newark Community Center Building, Newark, CA
  • Date: Saturday, August 1
  • Time: 10:00 AM–5:00 PM
u/aposaudio — 20 days ago

xDuoo TA-68 Balanced Tube Headphone Amplifier is now available

The TA-68 is xDuoo's fully balanced desktop tube headphone amplifier, using separate left and right tube circuits from input to output. The design combines two 5U4G rectifier tubes, two matched 12AU7 preamp tubes, four 6C19 buffer tubes, and a capacitor-coupled output stage.

A few details that stand out:

  • Fully balanced signal path
  • Independent left and right volume controls
  • Dual isolated EI power transformers
  • Vishay coupling capacitors and Nichicon audio-grade filter capacitors
  • XLR, 4.4 mm, and RCA inputs
  • 4-pin XLR, 4.4 mm, and 6.35 mm headphone outputs
  • 45-second relay protection delay
  • Recommended for 60–600 Ω headphones

The independent volume controls are an interesting addition. Besides correcting channel imbalance, they also let you make small image placement adjustments without changing the opposite channel.

Full specs and pricing are available on the Apos product page.

u/aposaudio — 21 days ago

ES Lab EHT-LPS Linear Power Supply for the EHT-7 now available

The ES Lab EHT-LPS is now available.

It's a dedicated linear power supply designed specifically for the ES Lab EHT-7 electrostatic headphone energizer. Inside is an audio-grade R-core transformer, dual LT3045 voltage regulators, Nichicon Fine Gold and Elna Silmic II capacitors, and EMI filtering, all working toward a stable 15V DC output with lower electrical noise.

A few highlights:

  • Dedicated for the ES Lab EHT-7 energizer
  • Audio-grade R-core transformer
  • Dual LT3045 voltage regulators
  • Nichicon Fine Gold and Elna Silmic II capacitors
  • Integrated EMI filtering
  • CNC-machined aluminium chassis
  • 15V DC output, up to 1A
  • Two-pin GX-16 output connector

If you're already using the EHT-7, this is the matching linear supply it was designed around.

More details here.

u/aposaudio — 22 days ago

Sennheiser HD 560S, HD 600, HD 660S2, and HD 800S are on sale through August 9

If you've been waiting for a price drop on Sennheiser's open-back lineup, several of their best-known models are currently discounted through August 9.

Included in the promotion:

  • HD 560S
  • HD 600
  • HD 660S2
  • HD 800S

Whether you're looking for a neutral reference headphone or stepping into Sennheiser's flagship open-back lineup, this is one of the better opportunities to pick one up.

The promotion ends August 9. Shop the sale while it's still available at Apos.

u/aposaudio — 23 days ago

Meze ARTA is now available at Apos

Meze has introduced the ARTA as its new flagship open-back planar magnetic headphone, positioned above the Elite.

The biggest change is the new MZ5 HΩ Hybrid Array driver, developed with Rinaro Isodynamics. At 225Ω, it's a high-impedance planar designed for desktop amplification, with a recommended 500 mW or more at its rated impedance. Meze says the design focuses on signal purity, thermal stability, and distortion below 0.05%.

The tuning is warm-neutral, with a presentation intended to feel spacious rather than intimate. The open-back grille also serves an acoustic purpose, using angled blades to diffuse rear-wave energy and reduce unwanted reflections.

ARTA ships with two magnetic ear pad sets. The Duo Angled pads lean richer, while the Slim Alcantara pads offer a smoother, more neutral balance. Every component is serviceable or replaceable, and both single-ended and balanced cables are included.

You can find the full specifications and pricing here.

u/aposaudio — 24 days ago

We're expanding our mech keys community

Hey r/mechanicalkeyboards, Apos here with a quick update you might be interested in.

As some of you may know, a few of us have been doing this awhile and worked for a place called (Mass)Drop once upon a time. We never wanted to step on any toes in the past, but since Drop officially announced they’re shutting down we’ve received some messages from old friends looking for a new place to make cool stuff.

Since we also like making cool stuff(especially cool keyboard stuff) we were very excited at the idea of getting back into it.

So, we are.

That’s about it really. We’re going to bring back some oldies, update some classics, and give people the chance to make new gems.

DSA Astrolokeys, Preonic rev4, GMK CYL Hyperfuse Origins, DSS Dolch, SA Retro, and plenty more on the way. Maybe you’ve got something rattling around in that ol’ noggin of yours that you want to make? Shoot us a message and let's cook(am I doing that right? I don't think I'm doing that right. I’m so old…)

Anyway, we’re excited to click and clack with the other old farts still around and any young blood that’ll have us.

See ya around

u/aposaudio — 2 months ago