SPECS THAT MATTER

Power: enough for all headphones except the most insane planars (Susvara, etc)
Noise: inaudible on all headphones and IEMs when in low or negative gain modes
Voice: microphone input is dead-silent, and you have manual control over gain so you can dominate the conversation 
Distortion: unmeasurable at normal listening levels, 100-1000x lower than the headphones you're using
Heat: top gets slightly warm when using external power supply
Size: very desk-friendly

OTHER SPECS

Frequency Response: 20Hz-20Khz, +/-0.2db

Maximum Power, 16 Ohms: 2000mW RMS
Maximum Power, 32 ohms: 1500mW RMS
Maximum Power, 50 ohms: 800mW RMS
Maximum Power, 300 ohms: 200mW RMS

THD: <0.0004%, 20Hz-20KHz, at 2V RMS
IMD: <0.0006%, CCIR

SNR: >114dB, A-weighted, referenced to 2V RMS

Crosstalk: >-75dB, 20Hz-20KHz

Output Impedance (headphones): 0.25 ohms

Output Impedance (line out): 75 ohms

Gain: Negative, Low, and High, selectable via front panel switch. Negative has maximum output of 0.67V RMS, Low has maximum output of 2V RMS, high has maximum output of 8.5VRMS when using the external wall adapter (Linear Override power supply). Maximum output is reduced 10dB when using USB power.

USB Receiver: C-Media CM6635 with custom firmware

DAC: ESS ES9018 with LM4562-based I/V and OPA1654 filter/processing stage

Sample Rates and Bit Depths: 

USB Playback: 16/44.1 to 32/384 supported without drivers on Windows 10/11, Mac, Linux, Android (any UAC 2 device) with autoswitching to UAC1 for PS4, PS5, and Switch consoles.

Mic Input: 48kHz

Optical Input: 16/44.1 to 24/192

Output Stage: TI OPA1656 (4 amp stages per channel) 

Power Supply: Via USB only, or via linear wall-wart (Linear Override). USB provides internal +/-5V rails, Linear Override provides +/-15V rails.

Power Consumption: 4W typical max from Linear Override supply, 500mA cap on USB input if USB powered, 0mA from USB if using Linear Override supply.

Size: 5 x 3.5 x 1.375” (including knob)

Weight: 1 lb

APx Report for Gunnr

What is this Soundstage Control thing you’re talking about and why do I want it?
Soundstage Control gives you two extra knobs on the front of Gunnr’s chassis that allow to to control Width and Presence. These are analog controls that work on any source, regardless of whether it’s a game or music, or what surround standard it’s encoded for. It also means you don't have to deal with software or apps to make it work.

• Width expands or contracts the scope of your hearing. Turning the knob to the right makes everything sound more expansive, and can help you identify sounds that would normally be masked. Turning it to the left blends the channels, which can make music sound more natural on headphones.
• Presence enhances or suppresses sounds that you’re most sensitive to. Turn the knob to the right to bring voices forward, or to hear small disturbances (wind rustling, twigs snapping, guns cocking, stuff like that), which can help you hear things before your opponents can. Turn to the left to suppress voices, to fix music mixes that are too shouty, or to compensate for headphones with too much midrange.

So it’s like you took those controls off the Syn and added it to a Hel+?
The Width and Presence controls are like the Syn, yes, but Gunnr is a heckuva lot more than a Hel+. It’s the most powerful and most versatile gaming device we’ve ever made, a complete re-thinking of Hel, starting with the Linear Override power supply.

And Linear Override power supply? What’s that?
Linear Override gives you more power…and more portability at the same time. Now, you can run Gunnr with a single USB-C cable—no external power needed! That means you don’t have to carry around another wall adapter. Just take it anywhere, plug in to any USB-C port capable of providing 500mA (that’s most of them, except iDevices), and you’re set. But you can also plug in the provided linear wall adapter, which then overrides the switching supply and gives you a lot more power and gain. You’ll actually hear the gain increase when you plug it in.

So I don’t need a separate USB-C or wall brick for power?
Not if you don’t want to.

Then why would I bring one?
To get more power for hard-to-drive headphones.

And when I use the linear wall supply, it’s a fancy audiophile linear power supply?
Absolutely. There are then no switching supplies on the main rails (there are for the 3.3V and 5V supplies, of course.)

Why this for gaming instead of something more convenient like Bluetooth?
Three words: quality, latency, and reliability. Bluetooth simply can’t deliver the quality of a wired connection. Not even lossless Bluetooth can operate above 48kHz. So if you want the best sound, with the most detail, for the most mission-critical gaming, you’re going wired. Add the near-unmeasurable latency of Gunnr’s USB implementation, total freedom from Bluetooth drop-outs and charging pauses, and Gunnr’s high-reliability design, and you have the one device you need for your most important games.

So I can connect to pretty much any TV and many console games, as well as PCs?
Yes. And Macs. And iPads. And phones and tablets. Gunnr is super-versatile.

But no support for Xbox?
Talk to them about UAC1 or UAC2 support. It’s not like they can’t do it. Not sure what their problem is. 

Why should I buy this over the Fulla? 
Because you want more power or flexibility. Gunnr offers much higher power than Fulla E, a gain switch for harder-to-drive or more sensitive headphones, Width and Presence controls, Linear Override power supply, a stereo mic input. If you don’t need that, Fulla is a great little DAC/amp. So there you go.

So this is just a gaming device?
Nope. It’s also great in your office. If you want great sound (and if you want to sound good to the people you’re staring at in the Zoom window), Gunnr is a great choice for office and home office communications.

Can I use this for Linux?
If your Linux distro supports UAC2 (as in, USB Audio Class 2, the standard for audio transmission over USB), then you’re set. However, we haven’t tested all distros. 

How about MacOS? 
Yep, you’re good.

iOS and iPadOS?
You will need to use external power for iOS and iPadOS, so the USB input will report as a 0mA device. You can use the supplied wall adapter or you can use a dongle with a separate USB power input from Apple.

Android?
In general, yes. Some older phones may need an external application such as USB Audio Player Pro to work. As with Linux, we haven’t tested all variations.

What about Windows 7 and 8.1?
Windows 10 and 11 only on this one.

How much power does this need from my computer or phone?
Gunnr draws up to 500mA if connected via USB with a single cable, and 0mA if you use the included wall-wart for a separate power input.

Can I use this with both headphones and powered monitors? 
Yep! All you’ll need is a 1/8” to dual RCA or dual XLR cable to connect to your monitors.

Can I use this as just a DAC?
Yep! Just put it in low gain (middle switch position) and turn it all the way up. Use the supplied wall adapter to get 2V out. Plug into the line out on the back panel and you’re set.

If I plug in headphones…
It automatically mutes the preamp outputs. See, we’re getting good at predicting what you’re gonna ask. Kinda like autocorrect. But with less embarrassing mistakes. We hope.

And the microphone input is stereo?
Yes. You can use an external stereo electret microphone if you’d like, or use the mono one built into your headset. Both work fine. But yes, there’s a really good TI ADC in there, together with an NE5532 pre-amp for gain, so it’s a very nice mic input.

Will it work with all of my headphones?
Pretty much anything, yeah. 2000mW is a ton of power. Even if you have planar headphones, it should run them to ear-bleeding levels. And if you have sensitive IEMs, you can use negative gain for a vanishingly low noise floor.

What comes in the box, besides the Gunnr? Do I get a cable with this?
Yes, we supply a USB-A to USB-C cable, as well as a 16VAC linear power adapter. Or if you don't want the adapter, you can save a few bucks. 

Can I use a fancier cable to get better sound?
You can do whatever you’d like, including dancing by the light of the full moon and making small, non-living sacrifices to the audiophile gods.

No, seriously.
We are being serious.

I’m asking specifically about the cable.
As long as it’s a USB 2.0-minimum USB-C terminated cable, you can use it, sure. 

And it’ll sound better?
Probably about as much as taping $100 bills to your headphones. Again, it’s your choice, up to you!

What is a Gunnr?
In Norse mythology, Gunnr was a Valkyrie. She rode a wolf and her name (cognate with the English word "gun") means battle. Pretty cool, huh?

Gunnr Manual