Review: HELM Audio DB12 AAAMP – Portable Power Turned Up to 12!

The HELM Audio DB12 AAAMP featuring THX technology.
The HELM Audio DB12 AAAMP featuring THX technology.

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The HELM Audio DB12 AAAMP boasts a little body, hefty power, and THX engineering cred.

First, a sincere thank you to Ari and HELM Audio for allowing Headphonesty to review the DB12 AAAMP. As is my standard, I did not read or watch any reviews of the DB12 before my evaluation.

If you made it this far, you likely know what this thing is – a portable audio amplifier, with this form factor being called a “dongle.” In general, dongles are devices that generate more clean power and sound than you might get from your mobile audio source (e.g., smartphone, tablet, laptop).

Bottom Line

The DB12 has some distinct real-world advantages. It will not occupy your mobile phone’s USB-C port if you have a 3.5mm jack. It has its own internal rechargeable battery supply and will not draw power from your source device. It can be used while charging or plugged in via USB-C. If your audio world is compatible with 3.5mm jacks and plugs, the DB12 is a super easy and convenient way to increase power anywhere without upgrading your source.

What We Like 😍
  • User experience is excellent and super simple plug-and-play use
  • High-quality build
  • Tiny and attractive form factor
  • Ultra-low ‘almost black’ noise floor at any volume
  • Onboard rechargeable battery
  • Bass boost is a grin-generator
  • Premium carry pouch
What We Don't Like 🤢
  • 3.5mm only (unless paired with another device such as the HELM Audio BOLT)
  • No customization or variable adjustment of bass boost (on/off)
  • +6 dB bass boost may be overwhelming for many consumer-tuned headphones
  • Hot swapping with power on can be hazardous to your ears and gear

The HELM DB12 AAAMP mobile headphone amplifier is the world’s first portable in-line amplifier powered by THX. Its name highlights two significant attributes: +12 dB of gain/power, provided by an internal THX-certified AAA (Achromatic Audio Amplifier) amplifier.

The DB12 AAAMP’s signal chain is analog from input to output. There is no DAC (Digital Audio Converter) on board – it’s an all-analog mobile amplifier with near zero distortion.

Do you need one? Maybe, or maybe not, as the answer depends on multiple factors. Follow along; your answer awaits!

Clean and simple packaging for a product of the same description.
Clean and simple packaging for a product of the same description.

First Impressions

The DB12’s compact, attractive aluminum case features three large, easy-to-feel buttons and a slider switch. Housing, fit, and finish feel high quality. It will not be mistaken for a generic dongle amplifier.

Company Overview

Founded in 2017 by a team of industry veterans with a passion for delivering better sound quality across all mobile devices, HELM Audio™ Ltd. is a British-American audio innovation and technology company.

“HELM products are designed, developed and engineered for groundbreaking performance, believing audiophiles and mass-market consumers alike are tired of the mediocre sound quality that other large audio brands find acceptable.” – HELM Audio

Technical Specifications

  • Form: Dongle-type portable headphone amplifier
  • Connections:
    • Input: Stereo TRRS 3.5 mm male connector (to connect to a source device)
    • Output: Stereo TRRS 3.5 mm female connector (to plug headphones into)
  • Performance:
    • Amplifier: THX’s AAA Amplifier, THX Certified
    • THD+N:
      • -102 dB, 32 ohms, 10 mW: 0.0008%
      • -102 dB, 32 ohms, 5 mW: 0.0008%
      • -109 dB, 10 Kohms, 0/049 mW: 0.00035%
    • SNR: 141 dB, 300 ohms, <1% THD
    • Crosstalk: -91 dB, 10K ohms: 0.0028184%
    • Gain: +12 db (full range)
    • Independent bass boost: +6 db (60-100 Hz frequencies)
    • Output Power:
      • 109mW @ 16 ohms, <0.1% THD (watts per channel)
      • 90mW @ 32 ohms, <0.1% THD (watts per channel): important note, this is accurate per HELM as of this publication. The output power specifications published in their documentation for 32 ohms is incorrect and pending correction.
    • Output impedance : <0.4 ohms
    • Frequency Response, 20 Hz – 20 kHz with 32 ohm load: +0.01 / -0.2 dB
  • On-device controls: hardware volume control (rocker switch) with 32 steps of volume scale
  • Power Supply: internal USB rechargeable battery, USB-C connection
  • Battery Life: 6-8 hours in use
  • Size: 70mm total length x 22mm x 12mm (2.75 x 0.57 x 0.88 inches)
  • Weight: 30.55 grams (1.08 ounces)

Packaging

A serious and sturdy two-piece cardboard black box opens to reveal a foam cutout securing the DB12. Below are the accessories, including a premium carrying case, which is much more than large enough to carry approximately 5 of the DB12. Or, more practically, one DB12 and 1-2 pairs of IEMs (in-ear monitors) – in their own cases!

The DB12 housed safely in its box with the basic necessities.
The DB12 housed safely in its box with the basic necessities.

In the box

  • HELM Audio DB12 AAAMP
  • USB-C cable
  • Soft leather-like embossed carrying bag
  • Quickstart guide
Devices that do not have a 3.5mm female input jack will need an additional USB or Lightning to 3.5mm dongle. This is best addressed by pairing it with the HELM Audio Bolt. For iOS devices, only MFI approved dongles are recommended by HELM.
Included are a short USB-C charging cable and a generously large carrying case.
Included are a short USB-C charging cable and a generously large carrying case.

Design

The DB12’s strong, compact, lightweight two-piece aluminum body is built well with tight tolerances and no loose parts. The rounded corners make for a nice feel in hand. It is smooth and resistant to fingerprints.

Large black plastic inline volume and playback controls for compatible devices are slightly raised from the body, making them easy to locate and identify without looking. There are three physical buttons with excellent positive feedback: volume up, volume down, and a multifunction button.

There is a small light on the body to indicate power on and bass boost on.
There is a small light on the body to indicate power on and bass boost on.
Inline controls are primarily designed for mobile devices and vary on PC, Gaming Consoles & Music Players.

The upside and downside of the small 3-position plastic slider switch are that it’s stiff and requires effort and precision pressure. Depending on your fingers, this slider can be challenging to shift into place and not overshoot the position you are going for. Once there, it will not move on its own or with an accidental swipe.

One side of the DB12 has a USB-C port to charge the device while the small light indicates battery status. The DB12 can be used while charging.
One side of the DB12 has a USB-C port to charge the device while the small light indicates battery status. The DB12 can be used while charging.

The aluminum dissipates heat and is remarkably resistant to fingerprinting and smudging (refrigerators claiming to do the same could learn a lesson or two from the DB12 materials experts). The DB12 as a physical device is noiseless and generates a slight warmth in use which I never find bothersome.

Cable

The high conductive silver coiled cables that extend from both sides of the unit are wrapped in cloth, flexible yet sturdy, and non-microphonic.

The cable’s length from the source to the DB12 is a very long 24”, and the distance from the body to the headphone adapter is 2”. This ensures that you can carry a phone or player in your pocket or bag and still access the inline controls without taking the device out.

The DB12 is compatible with 3.5mm equipped audio devices with extremely simple plug and play use.
The DB12 is compatible with 3.5mm equipped audio devices with extremely simple plug and play use.

Internals

The DB12 is powered by THX AAA technology to deliver studio-quality analog (gloriously not digital) amplification to any wired headphones. It delivers +12 dB of zero distortion volume gain.

“HELM Audio and THX claim that the DB12 improves stereo imaging and clarity through true linear amplification. The feed-forward error correction technology reduces harmonic, intermodulation, and crossover distortion by up to 40dB.” – HELM Audio

Additionally, the HELM DB12 AAAMP Mobile Headphone Amplifier is THX Certified. For Certified headphone listening products, THX engineers analyze everything from output levels, frequency response, signal-to-noise, distortion, and bass management to recreate high-impact cinema sound and best-in-class audio fidelity.

THX objective and standard: eradicate noise and distortion. (From: THX.com)
THX objective and standard: eradicate noise and distortion. (From: THX.com)

DB12 AAAMP Performance and Sound

Regarding performance, I have three main priorities with DAC/amps:

  1. Clean power
  2. Low noise
  3. Low distortion

Power

The DB12 produces a healthy amount of power for a tiny battery-powered dongle DAC/amp. 12dB of power gain from 109mW @ 16 ohms / 90mW @ 32 ohms may not sound like a lot, especially compared to other dongles that are powered by USB-C.

When using the DB12 inline with 3.5mm connections, remember that the total power available is in addition to whatever your source device produces.

For most headphones, including those with low-sensitivity and high-impedance that are hard to drive, the DB12 delivers adequate power on the go. My testing was successful with a range of Sennheiser headphones (58x Jubilee, HD650, HD599SE), the AKG Q701, and the Beyerdynamic DT990 Pro.

For almost all IEMs, the power available is far more than they will require (or your eardrums should safely be exposed to). While the DB12 will not introduce any noise, too much power will definitely cause distortion – and hearing damage. Be cautious with volume increases while you calibrate to how much extra power is at your disposal.

Matching well with the dashingly handsome Focal Elegia, the DB12 will power up most full size headphones to better performance.
Matching well with the dashingly handsome Focal Elegia, the DB12 will power up most full size headphones to better performance.
If you’d like to evaluate how this DB12 will do powering your headphones, please see Headphonesty’s super nifty Headphone Power Calculator!

Noise

A critical test for me, given my priorities above, is to check for unwanted noise. I plug in the headphones/IEMs and turn the volume up on the original source to maximum (with no signal playing), followed by increasing the volume on the amplifier to maximum, and I listen for hiss or noise.

On many DAC/amps, there is increasing noise in the form of hiss as the volume increases, though often not obvious when there is sound transmitting from the source.

The noise floor is incredibly low, meaning you will hear nothing, even with high-sensitivity headphones or IEMs.

The DB12's wears its THX badge of achievement with pride, being the very first of its type to achieve such status.
The DB12’s wears its THX badge of achievement with pride, being the very first of its type to achieve such status.

Sound

The primary benefit of the DB12 is significant extra power with a claimed ability to resolve/reduce up to 80% of the source THD output, which can clear up the sound significantly from low-quality sources thanks to THX.

It’s crucial to note that the DB12 will not alter frequency response (sound reproduction). This means it will not alter or significantly improve poor quality sources beyond cleaning up signal noise.

If you want a change in quality plus the power boost, it’s best to pair the DB12 with the BOLT, HELM’s DAC/amp with extensive capabilities. The BOLT produces approximately 60mW @ 32 ohms, raising their combined total power output to approximately 150mW @ 32 ohms when paired.

The DB12’s big party trick is the +6 dB bass boost. The DB12 can transform headphones and IEMs that sound a bit thin and cool into warmer and more engaging producers, delivering ear-shaking fun!

Depending on your preferences and gear, the bass boost may be a huge hit for you with endless grins or quite the opposite. The +6 dB lift in the 60-100 Hz frequencies is a bit of a blunt instrument, offering no variable steps in boost or adjustment of the application to different frequencies.

For reference, +6 dB is a LOT. Far from subtle, this comes with many caveats. If you have headphones/IEMs that are factory tuned with boosted bass frequencies, such as many “V”-shaped sets, the DB12’s big boost may overwhelm the drivers (i.e., cause stress beyond the driver’s capabilities), and therefore create distortion (and possibly damage) at high volumes.

For maximum performance, especially with IOS devices and those with USB-C output, pair the the DB12 with HELM's own BOLT DAC/amp.
For maximum performance, especially with IOS devices and those with USB-C output, pair the the DB12 with HELM’s own BOLT DAC/amp.

There may also be a resultant bleed into the lower midrange that clouds vocals and reduces overall clarity. This is not a huge issue for the most part unless you have a highly tuned ear or are listening at loud volumes.

On the other hand, for headphones like all the bass-light open-backs I mentioned above, the DB12’s boost can be a switch-inspired revelation for many who are not adept with EQ or modding.

I would be curious to hear a DB12 with bass boost extending approximately 20 Hz on either side of its range, at about +3 dB to smooth it all out and blend better into the upper bass and lower mids. If you want precision, skip the bass boost switch and use multi-band or parametric EQ.

Concerning real-world use, it will serve you well to watch this DB12 AAAMP Quick Start video from HELM Audio very carefully, especially regarding the proper lowering of source volumes.

Where to Buy

IYKYK (if you know, you know) - this is a mighty strong little device that can transform your music listening on the go!
IYKYK (if you know, you know) – this is a mighty strong little device that can transform your music listening on the go!

Conclusion

Let’s revisit the original question: do you need a portable amplifier dongle, specifically the DB12?

The DB12 has some distinct real-world advantages:

  • it will not occupy your mobile phone’s USB-C port if you have a 3.5mm jack
  • has its own internal rechargeable battery supply and will not draw power from your source device
  • can be used while charging or plugged in via USB-C

If your audio world is compatible with 3.5mm jacks and plugs, the DB12 is a super easy and convenient way to increase power anywhere without having to upgrade your source.

If you want increased power and improved sound, MQA unfolding, and real THX magic, the bundle of the HELM Audio BOLT and the DB12 are a perfect paring – they will impress you!

In short, I encounter circles with 3.5mm holes all the time in my world. This DB12 AAAMP has earned a place in my “take with” audio gear every day.

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