HeadRoom Micro Amp and Micro DAC
I love HeadRoom, but mine is no simple
fanboy crush -- Ive got good reasons for it. First, it was a HeadRoom amplifier, the
discontinued Little, that introduced me to the real joy of headphones and hooked me on
quality sound. Without HeadRoom, I probably wouldnt be writing for GoodSound!
now. Second, the release two years ago of the Total BitHead USB-enabled, battery-powered
headphone amp illustrated the inventive approach HeadRoom takes not only to product
development, but to company image as well. Third, in addition to its own website, www.headphone.com, HeadRoom has
supported headphone sites such as www.head-fi.org
since, well, before there was www.head-fi.org. And fourth, HeadRoom folk such as
its president, Tyll Hertsens, are some of the friendliest, most approachable people
HeadRooms Micro DAC digital-to-analog converter ($299
USD) and Micro Amp headphone amplifier ($299) have the same casework; only their
faceplates and innards differ. Each has an aluminum body 1.5"H by 3.5"W by
4.5"L. The DAC weighs 9 ounces, the Amp 9.6 ounces; both weights include the
batteries. That means the Micros weigh just over a pound together; in contrast, the Total
BitHead weighs 5.5 ounces. You dont need to be a he-man to carry around a pound, but
its a noticeable amount of weight. If youre walking around the city all day,
the Total BitHead is probably the better choice (hence its inclusion in HeadRooms
The Micro DAC and Amp cases have a slight convex curve and
rubber surrounds around their front and rear panels. These surrounds have long indents on
the top and ridges on the bottom, which allows the units to be secured to one another when
stacked. The connection is tight enough that you can move them around on your desk without
worrying that the top one will fall off.
Each rear panel has two thumbscrews (one on each end) that
allow the user to remove the plate to insert the two 9V batteries that power each unit.
HeadRoom claims a battery life of 15-18 hours for the Micro Amp, eight hours for the Micro
DAC. Dead center on each rear panel is an input for a wall-wart power supply (provided).
The batteries are inexpensive, and the convenience of not having to find an outlet meant
that I used the Micros exclusively with batteries. I found HeadRooms claimed battery
life to be conservative.
One thing all the Micros faceplates have in common is
HeadRooms new logo, ablaze with a red LED in the upper left corner. Starting at the
DACs front left is the line out on a 1/8" output, then a 1/8" input for
optical or coaxial digital signals. It wasnt as easy as I had hoped to find a
mini-optical adapter for a regular TosLink cable. It took me three RadioShacks to find
one; apparently, this adapter has been discontinued. You may want to make sure you have
one on hand if you plan to use the Micro DAC with such a connection. Next is a USB input
so that you can use the Micro DAC with your computers, then two identical switches: the
input selector (optical, coaxial, or USB) and the power switch (external or battery
Like the Total BitHead, the Micro DAC uses the Texas
Instruments/Burr-Brown PSM2902 USB chip. Unlike the BitHead, the DAC uses this chip only
to convert the USB signal into a S/PDIF digital signal, which is then processed by a
Cirrus CS4398 DAC chip. The Micro DACs coaxial and optical inputs can accept word
lengths of 16 to 24 bits at 44.1kHz, 48kHz, or 96kHz.
On the left of the Micro Amps faceplate is a line
input, then the headphone output, both 1/8" connections. In the middle are two small
switches: the first toggles HeadRooms Crossfeed circuit on and off, and the second
selects among three gain levels: High, Low, and Medium. Next is a volume knob thats
big enough to grab easily, or find by touch if your amp is in a briefcase or backpack.
Last is the power switch, to select external or battery power.
HeadRoom has a
lot to say about their Crossfeed circuit on their website. Briefly, it sends some of
the signal from the right channel to the left, and some of the signal from the left
channel to the right. HeadRoom claims this helps create a coherent aural picture instead
of a separate blob of sound in each ear. The usefulness of Crossfeed seems to vary with
HeadRoom also provides some neat ways of carrying the
little Micros around. The Micro Strap goes around the Micro Amp, and provides a platform
on which you can secure your MP3 player with Velcro. A kickstand lets you tilt the player
up so that you can see it clearly while sitting at your desk. When youre ready to
head out the door, you can carry the Micros in a Micro Bag. To use the Amp and DAC
together when on the go, youll need the Micro Strap Extender, which secures both
units, and a bigger Micro Bag. If this is confusing, a call to the nice people at
HeadRoom, at (800) 828-8184 or (406) 587-9466, will get you squared away on which bag
suits your needs.
I did most of my listening with the Micros using my laptop
computer and the iTunes library Ive compiled for my iPod. The tracks have varying
bit rates, but nothing is less than 192kHz. I also used the Micros with a Sony SCE-775
SACD player with an optical cable feeding the Micro DAC. I used both Grado SR-60 and
Etymotic ER4P headphones, but the specific review observations here refer exclusively to
my listening with the Etymotics.
The first album I used to evaluate the Micros was David
Johansen and the Harry Smiths Shaker [CD, Chesky JD236] -- good sound and
toe-tappin blues. On "Let the Mermaid Flirt with Me," instruments such as
brushed drums and acoustic guitar were reproduced with truthful timbres. This was one of
those recordings nicely helped by HeadRooms Crossfeed circuit. The tracks
bizarre separation of instruments in the left and right channels works fine on speakers
but is unsettling on headphones. Crossfeed helped me enjoy the music without obsessing
over the instruments placements inside my head.
I then played the always fun (and eponymous) album by the
Scissor Sisters [CD, Universal B0002772-02]. The opening percussion and guitar of
"Take Your Mama" were crisp and clean, but I knew within seconds that the
batteries in either the Micro Amp or the Micro DAC were dying -- the sound quickly became
distorted. Luckily, I had extra batteries ready to go. Up and running again, I noticed how
deep and powerful the bass was. It was even more noticeably deep and controlled on Their
Law, the new greatest-hits collection from The Prodigy [CD, XL XLCD190].
I chose the Scissor Sisters and Prodigy albums because I
listen to both frequently on my iPod. This gave me a good baseline from which to compare
the Micros. The difference was like night and day. My overall impression of the sound
quality of these albums went from "OK" to "very good." No need to
worry that the Micros werent doing their job.
On recordings such as Bob Dylans Desire [Columbia
CH 90318], I was impressed with the soundstage the Micro combo portrayed. The tambourine,
piano, and drums on "Isis" offered a very wide picture, not the narrowly
confined one that headphones sometimes produce -- and the tambourines sound was
The most noticeable improvements introduced by the Micros
were a bigger soundstage, better resolution, and a wider dynamic range. Played on my iPod
or directly from my computer, these same tracks sound pretty lifeless, their dynamic
ranges inconsistent with those of the original recordings. The Micros helped fix that
I compared the HeadRoom Micros with two other headphone
rigs: HeadRooms own Total BitHead, which Ive used for laptop listening since
2004, and Benchmarks DAC1, which isnt portable but has received widespread
enough praise to become something of a . . . benchmark. Neither competed directly with the
Micro DAC-Amp, for two reasons. First, the Total BitHead retails for $199 and the
Benchmark for $975; neither is in the price class of the Micros, which together cost $598.
Second, the Total BitHead allows for similar functionality as the Micros, but the
Benchmark has no USB input and cant be used as a portable.
The Micros blew the Total BitHead out of the water. On
"Belleville Rendez-Vous (French Version)," from the soundtrack of The
Triplets of Belleville [CD, Higher Octave 96811 2], the Micro Amp and DAC were better
able to catch nuances and resolve detail. Toward the very beginning of this track are some
sounds that are often imperceptible through speakers, but the DAC-Amp displayed them
perfectly through headphones. Another example of this occurs about two minutes into the
track, when some percussion instruments enter. The Micros articulated these sounds well
and made them distinct from other instruments in the mix.
The Total BitHeads presentation of the music was much
more laid-back than the Micros. When the bass kicks in on the Belleville
track, the Micros almost had me up and dancing; the Total BitHead only made me tap my
feet. Depending on your application, this might be preferable -- with the Total BitHead, I
was able to attend to e-mail and other online tasks while still enjoying the music, but
the Micros had me paying too much attention to the music to get anything else done. The
Micros replace the sweetness of the Total BitHead with a more detailed, precise sound.
Still, the Total BitHead is much smaller and lighter, and
attaches nicely with Velcro to the back of my laptops screen. That isnt going
to happen with the Micros. The BitHead can also run entirely off power derived from its
USB connection to the computer; no such luck with the Micros. Ill continue to use
the BitHead with my laptop, because portability is important for me. If I had a desktop
computer, however, the better sound of the Micros would inspire me to replace the BitHead
Because this review focuses on the combination of the Micro
DAC and Micro Amp, thats how I compared them with the Benchmark DAC1; I didnt
evaluate the Micro Amp separately. The Micros gave a wider soundstage and a mellower sound
than the Benchmark, which offered better instrumental timbres, more detail, and deeper
bass. These characteristics were easily heard using one of my perennial favorites, Charles
Minguss Mingus Ah Um [CD, Columbia/Legacy CK 65512]. On "Goodbye
Pork Pie Hat," the Micro combination made the instruments seem spread out in space
but failed to offer the last bits of detail -- such as the fingers of one of the horn
players tapping his instrument. Similarly, the Benchmark was better at separating
instruments from one another. The upbeat opening of "Better Git It In Your Soul"
has lots of instruments and at least one voice. Listening to this track through the
Benchmark, I heard very sharp images of each and every one of these sounds, but in a more
confined space than through the HeadRoom Micros. The images of the instruments were softer
through the HeadRooms, but the space the musicians occupied extended well past the
soundstage the Benchmark provided.
The good news for headphone enthusiasts is that there is
now a plethora of products available to enhance their listening pleasure. Thats also
the bad news. You can choose from the ultraportable Total BitHead to portable but bulky
solutions such as the Micros, tubed headphone amps, and beyond. You need to consider which
characteristics are important to you, how you listen to headphones, and how much you want
to spend on a headphone system. Theres no easy solution, so allow the auditioning
process to be a fun addition to your hobby.
HeadRooms Micro Amp quickly took over from the Total
BitHead as my favorite inexpensive headphone amplifier. The sound it produced simply had
more clarity and a feeling of more power behind it. But unlike the BitHead, it lacks a USB
input, so theres a tradeoff. To add USB functionality to the Micro Amp youll
need the Micro DAC, but the combo costs three times as much as the BitHead. If I sat in
front of a computer all day listening to headphones, Id probably consider the money
well spent. If more portable players had digital outputs, the setup could be invaluable.
But the Micro combo costs $598. The Total BitHead wont give you the same
performance, but it will give you better sound than your computer or iPod will on its own,
and will keep $399 in your pocket.
The Micro DAC and Micro Amp perform as well as anyone could
hope, are finished to high standards, and fill the largely ignored niche of USB-enabled
portable audio components. HeadRoom provides excellent customer service and aggressively
supports headphone hobbyists. With the Micros, my love affair with HeadRoom products
Prices of equipment reviewed