AUDIOENGINE HD6 POWERED SPEAKERS REVIEW
JIM CLEMENTS
SEPTEMBER 14, 2016
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BOOKSHELF SPEAKERS
Audioengine’s new HD6 powered speakers have flexible hook up options –
analog, optical or Bluetooth.
They are solidly built and impressed me with their excellent imaging, dynamic midrange and
tunefull bass response. They are available in three different finish options, all of which are high
quality and very stylish. These are the type of speakers one would be happy to use for the rest of
their life.
Highlights
Audioengine HD6 Powered Speakers
• Flexible input options – analog, digital and Bluetooth
• Surprising bass extension
• Neutral, precise midrange
• Extended, albeit “polite” treble response
• Incredible soundstage depth
• Plenty of amplifier power for mid sized rooms
• Beautiful Real Wood Finishes with excellent build quality
Introduction
I have always admired Audioengine because of their knack for creating high quality, affordable gear.
For those who may not know, Audioengine started in the mid aughts of the 21st century and have
since focused on innovative, compact powered speaker systems, stand-alone DAC’s and
miscellaneous wireless applications. Their products have garnered rave reviews from consumers
and the press. Their products are always high quality and high value prospects for modern music
lovers.
AUDIOENGINE POWERED SPEAKERS REVIEW SPECIFICATIONS
DESIGN:
WEIGHT:
POWER:
channel/passive)
2-Way Slot-Loaded, Powered Speakers
50 wpc RMS
17.5 lbs. (Left channel/amp) and 12.5 lbs. (Right
DIMENSIONS:
11.75” H x 7.25” W x 10” D
MFR:
50 Hz – 22 kHz, +/- 1.5dB
AVAILABLE FINISHES:
Real Cherry, Real Walnut or Satin Black Paint
TWEETER:
1" Silk Dome
MSRP (PAIR):
$749 USD
WOOFER:
5-1/2” Kevlar cone
COMPANY:
Audioengine
CROSSOVER FREQUENCY:
Not stated
SECRETS TAGS:
INPUTS:
3.5mm mini-jack, RCA L/R, digital optical (SPDIF,)
Bluetooth aptX
Audioengine, HD6, Powered speakers, Bluetooth,
Bookshelf speakers, Bookshelf Speaker Reviews 2016
CODEC:
Up to 24-bit/192 kHz sample rates
This is the second formal review I have done of something made by Audioengine. My first review of
an Audioengine product was in January 2015 where I reviewed the B1 Bluetooth receiver. That
product impressed me so much that I nominated it for the Accessory of the Year in 2015. The HD6’s
were announced a few months later in November 2015. It took a while until everything synched up
so I could get a pair of HD6’s in for review. I’ve had them for a few months now and can say that,
true to form for Audioengine, they are an excellent deal at only $749 a pair.
Design
The Audioengine HD6 speakers are mid-sized powered bookshelf speakers with a built-in DAC and
Bluetooth receiver. The HD6’s are larger than the mini speakers you would normally see in most
common desktop solutions for gaming and/or a computer workstations. At the same time they are
much smaller than the bookshelf speakers that would typically find their way into an audiophile’s
living room system. I mostly listened to them on the credenza in my office as they were maybe a
smidgen too big for the desk itself.
The HD6’s are very stoutly constructed, a fact evidenced by their solid weight. The amplification is
all contained in the left speaker so, of course, this is the heavier speaker. I was honestly expecting
the amplifier to be a lightweight Class D design largely because Audioengine, the company, is a
cutting-edge component manufacturer so of course they would use the most up to date amplifier
topology, right? Well, surprise – the HD6’s are powered by a pair of Class A/B monoblock power
amplifiers. Audioengine says these amps have built-in linear power supplies with toroidal power
transformers and are rated to deliver 50 wpc RMS (<0.05% THD+N).
So that’s really cool. It’s a decent amount of power from a tried and true technology and with
performance upgrades that are also known to improve the sound. But Audioengine, being who
they are, didn’t stop there. No siree. They went ahead and made these speaker whole by including a
built-in D1 24-bit DAC.
This DAC is based on the AKM AK4396A chip. This is a high end DAC solution and means the HD6’s
are capable of decoding digital signals up to 24-bit/192 kHz via the optical input! So the inclusion of
a built-in high end DAC sets apart the HD6’s, right?
Sorry, but Audioengine didn’t stop there. They also included a built-in B1 Bluetooth® Receiver with
aptX®. The B1 features 24-bit upsampling and it is described by Audioengine in their own words, “. .
. for Bluetooth the AK4396A is used as an upsampling DAC and will pad all bit depths to 24-bits,
achieving a higher signal-to-noise ratio and lower noise floor. Due to the high signal-to-noise specs
of the AK4396A, the fact that digital signal is upsampled to 24-bits – as well as the added benefit of
onboard triple redundancy power source conversion and filtering – the HD6 Bluetooth
implementation presents impressive low noise and low distortion characteristics with a noticeable
improvement over other Bluetooth devices.”
Not only does this mean that the HD6’s are highly flexible in terms of the type of signals they can
accommodate, but they also handle those signals like a champ!
The drivers in the HD6’s are well-designed and manufactured for the specific needs of this system.
The woofers are custom 5.5” Kevlar drivers with die cast aluminum baskets. They are slot-loaded
via a slotted port at the top back of each cabinet.
The tweeters are custom 1” silk dome tweeters with neodymium magnets and ferrofluid-cooled
voice coils that are recessed into some modest waveguides.
These drivers are mounted in solidly made cabinets of ¾” (20 mm) thick MDF cabinets. There are
three finish options. Two are real wood veneers with furniture-grade finishes – cherry and walnut.
Or you could choose the third option, satin black paint for a more subdued look.
Like I mentioned above, the amps and electronics are in the left speaker. The back panel of the
plate amp has a lighted “pair” button, a detachable Bluetooth antenna, analog ins (mini plug and
RCA), optical in, RCA stereo out, binding posts for speaker level out to the right speaker, a power
switch and fuse protection. The front of the cabinet has a lovely aluminum accent along the bottom
which also has a rotary volume control.
The speakers come with a nice little solid aluminum remote control with buttons for standby,
power, and volume up/down. I used the remote a lot during the review period and it was indeed a
most welcome touch.
The grilles are detachable and magnetic (with sufficiently strong magnets, BTW). There are also
threaded inserts in the base of each cabinet that can be used to secure the speakers to a pair of
stands.
Set-up
The first thing I did after receiving these speakers was to set them up in the big theater space to get
a taste of their sound. Even fresh out of the box, the sound was rich and solid in the bass with a
delicate, slightly recessed top end. I liked what I heard and when this happens, I tend to crank it up
and let the sound wash over me. I quickly found the upper volume limit with the HD6’s in the big
room so I knew the only way to properly evaluate these speakers would be in a smaller space. So I
took them to my office.
My office is about 175 square feet with a suspended acoustic ceiling. Though I have a big desk, I am
an engineer which means I have lots of large format pieces of paper I need to manage so there
really wasn’t enough space on the desk for the mid sized HD6’s. That’s why I placed them on the
credenza in the front of the room. (If I didn’t have all the plan sheets, then they would have been on
the desk, straddling my monitors.) In any event, the speakers were spaced about 6′ apart and were
about 8′ from the listening position. I think this was an almost ideal geometric set up for the system
considering all relevant factors.
Once I found the best spot for the HD6’s, the final set up was a breeze. I connected the supplied
speaker cable from the plate amp to the right speaker. I connected the optical out from an Oppo
BDP 83 SE to the optical in on the DAC, installed the Bluetooth antenna, connected the power cord
and then paired my PC and phone to the Audioengines. That was it. The whole set up took just a
few minutes.
In Use
I played music over the HD6’s for several weeks before doing any critical listening. I did not hear
much in the way of a transformation over this break-in period which is atypical of most speakers I
review. Most speakers go through some amount of transformation when breaking in but in this
case I did not hear any substantial change. (Perhaps Audioengine did a little break-in before
shipping them to me?)
Richard Thompson “Rumor and Sigh”
Once I was ready to evaluate the sound, I put on the old Richard
Thompson Rumor and Sigh CD. There is a variety of interesting
instrumentation throughout this well-recorded album which makes for
excellent test material. All the instruments have their own unique
characteristics (and are mostly acoustic) so this CD is a very good one to
use in evaluating a system.
One standout song on the album is “Mystery Wind”. My notes say “wow, just wow, the bass
extension and definition are way beyond anything I would have expected. The synth lines are
something to behold!” The frequency balance was not hyped but was natural and very satisfying.
Imaging was top notch as well. The voices were slightly forward but not in your face. It was great to
be able to hear and understand all the lyrics!
Another great song on this album is “God Loves a Drunk”. The HD6’s were rock solid on this song.
This went for the guitar, the vocals and the cello. This time, though, the image sounded ever so
slightly compressed.
Later on the CD, I was amazed by the bass on “Psycho Street”. The HD6’s really did rival full range
floor standers in this regard. They were phenomenal.
Pink Floyd “Wish You Were Here”
Next up was the recently remastered Pink Floyd Wish You Were Here SACD.
This time, I used the unbalanced analog outs on the Oppo to the RCA ins
on the Audioengine HD6’s.
Once again, I was totally impressed with the overall bass quality and
extension, especially on “Welcome to the Machine”. Additionally, the
substantial soundstage breadth and depth were significantly more
immersive than I was expecting.
“Have a Cigar” is my favorite track on this album. I love the music, the arrangement, the
performance, the theme and this song makes me chuckle a little every time I hear it, even after all
these years. This was very immersive sounding again and I ultimately decided the excellent
immersion was mostly due to the front to back depth of the stage.
Similar to most every quality system I’ve reviewed, the HD6’s benefit from a correct volume setting
– too soft and the sound loses its life and edge, too loud and it becomes hard and out of balance,
just right and everything pops into place – instrument placement, staging, frequency balance, etc.
This was one reason I liked having the remote. I could fine tune the volume from my desk and didn’t
have to walk back and forth from the speakers to get the setting I wanted.
I did want more sparkle from the tweeters, particularly when using the Bluetooth interface. This
was the closest thing to a negative critique that I could make with the HD6’s – that some rock songs
just didn’t sparkle the way I am used to hearing. This didn’t come across as a lack of extension in
the treble. It was just that the treble was slightly recessed and this made for a warmer than usual
presentation overall. So the recessed treble was only noted with crash cymbals and other signals in
the range of, say 7 – 10 kHz. Remember that this quality was really only an issue when using the
Bluetooth input and not the analog or optical inputs – over these inputs, the voicing of the HD6’s
was remarkably neutral.
Hilary Hahn “Beethoven: Violin Concerto”
I would be remiss if I didn’t listen to a little Classical music with these
speakers. I felt that the HD6’s were stellar on most acoustic works so I put
on Hilary Hahn Beethoven: Violin Concerto and Bernstein: Serenade “After
Plato’s Symposium near the tail end of my evaluation period. Not only did
the Audioengine HD6’s describe the size and scope of the hall where these
performances were recorded, but they also passed on the natural sound
of Ms. Hahn’s violin. This is the great test of a speaker – how well does the
speaker recreate the sound of actual instruments? Well, the HD6’s did this
fabulously, preserving the innate and natural timbre of the strings and the
instrument’s wooden body.
Conclusions
THE AUDIOENGINE HD6 POWERED SPEAKERS are Among the Most Flexible
and Best-sounding Bookshelf Speakers I Have Reviewed.
LIKES
WOULD LIKE TO SEE
• All in one solution
• Asynchronous USB Input
• Lovely build and finish qualities
• WiFi Capability
• Decent amplification power
• Treble “Lift” switch
• Excellent soundstaging ability
• More finish options (e.g., Walnut)
• Solid and musical bass response
The HD6’s represent the next advancement of ideas from Audioengine so naturally they have a lot
of things going for them. Their strengths lie in their build quality, soundstaging, bass response and
flexibility. The HD6’s really are a complete system that can be used in a wide range of domestic
applications – a bedroom system, a desktop system or a main system in a medium to small room.
I am using them in my office for music playback while I work and for serious listening when the
opportunity presents itself. They are an ideal match for just such an application. They are voiced to
be less in-your-face than most compact speakers and this is a welcome respite from the
competition with their oft time hard-sounding playback. The HD6’s don’t wear on you throughout
the day.
I am strongly recommending the HD6’s for consideration if you are in the market for a small
system. I can’t think of any system I have heard that does as much and for such a reasonable price.
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