Little Labs MONOTOR User manual

MONOTOR
Operators Manual

manual printing & pdf formatting 04/2016.
Updated 06/2023
using this manual or any part of it without
permission is a violation of copyright laws.
monotor is a registered trademark of little
labs.

read this first
before using the monotor
ere is lots more in this manual, but please read this even if you do not read manuals;
anks!
e external power supply for the MONOTOR must be the 16-volt 0.3 amp dc regu-
lated bipolar unit supplied with it. If it is labeled INPHASE engineering, it is our new
custom-made for audio switcher, and you don’t need to worry about voltages in other
countries. If it is labeled Advanced Power Solutions, it is a linear supply and MUST
BE SWITCHED TO THE PROPER VOLTAGE for the country using it. If you don’t
change the voltage (obvious to some of you), and it is set for 110 volts, and you plug it
into 220 volts, it will BLOW UP the supply, possibly damaging the MONOTOR. If you
set it to 220 volts and plug it into 110 volts, the performance of the MONOTOR will
be severely degraded.
e dc power connector jack used on the MONOTOR looks like a CB microphone
connector. Although dicult to misalign because it is keyed, take care to align the plug
and jack properly when inserting.
e 3.5 mini jack sums what is plugged into it with the signal from the main trs/xlr
jacks but after the MONOTORs level potentiometer and mono functions.
So the volume when using this 3.5 mm jack will be controlled by what is feeding it
(e.g., iPod, phone).
Do not place the MONOTOR in close proximity to a Wi-Fi router; the high gain
circuitry, although well shielded in the MONOTOR, will pick up Wi-Fi “chirps,” which
are rectied rf signals. Wi-Fi routers have no place near any high-end audio gear.
e Monotor is vulnerable to failure by extreme static discharge. In dry environments
prone to static, use de-stat on carpets and discharge yourself before touching and placing
headphones on your head. Metal body headphones and planar magnetic phones are
particularly strong static magnets.
e trs/xlr and trs jacks on the MONOTOR are balanced, but the source can be
balanced or unbalanced. For rca plugs, you will need a ts (tip-sleeve) to rca adapter or a
cable made for the purpose. e adapter will connect the ring of the jack to the sleeve. If
making a rca to trs cable, tie the ring and sleeve of the trs to ground and shield with the
tip hot. If making a rca to xlr cable, tie pins one and three together of the male xlr, with
pin two hot.

ank you for purchasing the Little Labs MONOTOR™ source analyzing
professional headphone amp.
e MONOTOR is designed to fulll the need for professional monitoring
at the highest resolution possible, allowing long, fatigue-free analytical
listening sessions.
Headphone listening amounts to 80% of what the consumer listens with
today, and as the world gets more populated, this percentage will increase.
For the professional mixer, monitoring on headphones is not only necessary
but essential.
As a tech at A&M records recording studios and mastering rooms throughout
the ‘80s and ‘90s, I found the studio control rooms, although excellent
rooms and ne for evaluating a balance, they never came close to having
the high-resolution monitoring capabilities of the mastering rooms. Every
component in the audio signal chain of the mastering rooms was carefully
selected, and anything unnecessary was deleted; compared to the studios
large mixing consoles going through (necessarily) dozens of ampliers before
reaching your ears, the resolution between the two was readily apparent.
e mastering rooms were very carefully appointed under the direction
of a legendary sta of mastering engineer greats, including Alan Yoshida,
Bernie Grundman, Patricia Sullivan, Dave Collins, Stephen Marcussen,
and others throughout the years. Much of the electronics used were built
in-house. In these rooms, we could analyze minute dierences in the
sonic signature of components; even dierent brands of resistors could be
detected and evaluated for sonic neutrality. ese well-appointed rooms
allowed us to have a mastering chain that would allow an engineer to come
in and hear details such as edits, hums, hiss, unwanted distortions, and
reverb tails, which would often go unnoticed in the studio control room
thanks and a little background on the
monotors development

environment—allowing a nal polish to be put on a mix, with the engineer
condent that no matter what system the consumer played it on, all that
would be heard would be what was intended.
Fast forward to 2016, a much dierent recording monitoring environment
is the norm, often makeshift and acoustically imperfect. Despite huge
quality improvements in digital technology, the monitoring environment
has, in most cases, become less than ideal, and resolution has suered.
e Little Labs MONOTOR was designed so two people per MONOTOR
(each headphone out is independently powered) could listen deep into a
track at the highest resolution possible when paired with a quality set of
headphones.
e headphone amp in the pro world has been neglected with few oerings,
most of it junk, or the more expensive stu available includes the gimmick
cross-feed circuitry, and quite often is driven by several active stages with
unsuitable output drivers, great for old consoles to get a guitar sound, but
not for driving high-resolution headphones.
Many audiophile headphone amps exist with often euphonic yet inaccurate
reproduction and at a ridiculous price. A trend of digital to analog converters
combined with headphone amps is also popular. Some of the digital-to-
analog converters are of decent quality. Still, a studio or mastering facility
will typically have much better in-house digital-to-analog converters (the
MONOTOR makes evaluating converters easy).
e USB-powered headphone amp/digital to analog converters are crippled
by default by dc to dc converters used to squeeze every bit of power out
of a USB port.
Internally powered and Bluetooth headphones are also crippled by a
neutered power supply.

I’m not saying these headphone amps sound bad; it’s just that they are not
at a level of resolution found in a properly appointed mastering facility.
e Little Labs MONOTOR is designed with (what I call) a zen circuit
topology. Only a single state-of-the-art active stage is used at its optimum
gain, in the circuit path of each headphone ear, with all else straight wire
passive (this includes all the mono functions as well). All passive components
in the audio path were selected for sonic neutrality; this includes Dale/
Vishay resistors, Nichicon Muse series caps, and specialized polystyrene
lm decoupling caps. e MONOTOR uses a full voltage state-of-the-art
super low noise internal linear regulation system (4 uVrms) with massive
capacitance for power on demand on each rail. Just one internal lter
capacitor used (there are 6) is bigger than a whole USB dongle digital to
analog converter/headphone amp. is level of component selectivity allows
for a noticeably improved dynamic range over other headphone amps. You
can drive high-impedance phones to full volume without any strain. e
MONOTOR, when I say it is state of the art, it truly is, and could not
have been built just a year ago. I’m proud to say this is not a rehashed old
analog circuit; with this labor of love, we’ve taken analog to another level.
e MONOTOR, paired with a good set of headphones, will give you a
reference at the highest resolution, so in imperfect environments, you’ll
quickly be able to evaluate as you only could in the best mastering facilities.
You might wonder what I use for headphones (the headphone eld has
become huge in the last ten years). e reference I use with the MONOTOR
is the relatively reasonably cost Sennheiser HD600 with a Cardas cable
(cable given to me by Bernie Grundman’s Mastering facility and ex-A&M
super tech Beno May, thanks, Beno)! is simple setup will set you back
less than $1000 (slightly more with the Cardas cable) and give you the
performance you could easily spend ten times that trying to achieve, with
most likely worse resolution. Your favorite headphones are more than likely
suitable for the MONOTOR. Another popular headphone used with the

Monotor is the Audeze LCD-X which I love the bass response of. Still,
I’m partial to the neutral mid-range on the HD600. I use for tracking the
closed-back Audo Technica ATH M50. I do not recommend pairing with
the monotor, low impedance, super ecient, typically IEMS (but some
headphones also), which can get too loud too quickly and not give you
adequate volume range on the level control.
So cheers, thank you for your purchase and be sure to look at the rest of
the manual (especially the read this rst part).
anks to all the people for the help, patience, and good insights while
developing this product, e late Zack McCormley (DTS), John Caldwell
(Texas Instruments), Raymond and George Lui (G&J mfg), and my
wonderfully supportive amazing girlfriend, Randi Kory.
Happy Listening,
Jonathan Little

The front of the monotor has four headphone output jacks, two
3.5mm and two 1/4” . The two jacks to the left are fed by one stereo
amp and the two jacks to the right are fed by a separate stereo amp.
For the best performance use one set of phones per stereo amp
output. But if you need to use all four, you will not damage the
monotor and performance difference for casual use is minimal.
The little holes on either side of the level potentiometer conceal a push switch set back about an inch. The left switch pushed in bypasses the left side of the level potentiometer, the right, the right side of the level potentiometer. These can be used for a variety of scenarios (see more in the manual). The most common is when using the monotor with a high quality digital to analog converter that has a built in level control (like the Oppo 105). The highest quality level pot is no level pot.
Stereo / mono function switch selects: stereo reverse (maybe that hi hat sounds better on the right?), regular stereo, mono left plus right, left only (in
both ears), right only (in both ears), left minus right for hearing what is out of
phase (between what is feeding the left and right in) and also useful for compressed digital audio file artifact analysis.
front hook up

The xlr trs combo jacks and
trs stack jacks are in paralell
with each other.
Shown here with powered
speakers connected to the
trs jacks used as a thru.
The stereo aux in mini jack can be fed from a phone or any
3.5mm stereo jack device, including ipods or stereo video
camera mic headphone outs (talkback). This input sums with
the main inputs post the mono functions and volume control.
The xlr combo jack inputs to the MONOTOR are typically fed from line level sources such as your stereo buss of your console, the output of your D to A converter, the output of the monitor section of your console, a cd or dvd player, a phono pre amp. a tape machine, or to any line level device you want to monitor. The inputs to the MONOTOR are balanced, but the source can be balanced or unbalanced.
rear hook up

The xlt trs combo jacks and trs jacks
are in paralell with each other.
Shown here with multiple monotors
daisy chained.
The xlr combo jack inputs to the
MONOTOR are typically fed from line
level sources such as your stereo
buss of your console, the output of
your D to A converter, the output of
the monitor section of your console, a
cd or dvd player, a phono pre amp. a
tape machine, or to any line level
device you want to monitor.
The
inputs to the MONOTOR are balanced but the source can be balanced or unbalanced.
daisy chain hook up