Linear Tube Audio Z10 Series User manual

USER GUIDE: Z10 Integrated Amplifier
Linear Tube Audio Takoma Park, MD, USA
301-448-1534 [email protected]
WARNING: For safety, the cover of this amplifier should be secured
at all times.
This amplifier contains extremely high voltages and the user should
not attempt to service the amplifier. Furthermore, this amplifier
generates radio-frequency energy that can interfere with
communications equipment.
Introduction
The Z10 Integrated Amplifier (Z10i) combines our ZOTL10 power
amplifier with a Berning-designed preamplification stage and LTA’s
digital control system. The result is an integrated amp with a
precision stepped attenuator, tube-coupled balanced inputs, and
a reference-level headphone amplifier, all able to be operated
via remote control.

Limited Two-Year Warranty*
1. Your new product is covered by a limited two-year warranty
against defects in material and workmanship. Any repairs
required will be made at no charge within the first two years after
purchase as a new unit.
2. Any units returned for warranty repair must be shipped prepaid
after receiving return authorization. If possible, the unit should be
shipped in its original packaging. If this is not possible, the unit
should be well packed with particular attention paid to protection
of all corners and avoidance of any looseness in the carton.
3. This warranty does not apply to damage resulting from physical
abuse or unauthorized alterations or repairs, or from tube rolling or
adapter use, or from the use of third-party components, or
damage to exterior finish resulting from careless use.
4. The warranty is void if the serial number has been removed,
altered, or defaced.
5. This warranty is void if improper voltage is applied to any input or
output.
6. If Linear Tube Audio determines after receiving the unit that
damage was misrepresented and has been caused by something
not covered by the warranty, the customer must pay for any
necessary repairs before the unit is returned to the customer.
7. Linear Tube Audio reserves the right to improve or change its
products without obligation to modify previously manufactured
units.
* Applicable for domestic sales only. There is a one year warranty
for overseas customers. Handling and shipping costs are the
responsibility of the overseas customer.
Service Note
ZOTL amplifiers use a unique circuit and even trained technicians
familiar with tube amplifiers may not know how to correctly work
on LTA products. Please contact us before attempting any
alteration or repair, whether you are concerned about the
warranty or not.

Specifications
Circuit Type: Push-Pull Class A
Speaker Output: 12W (4 Ohm), 10W (8 Ohm)
Headphone Output: HI: 2W (50 Ohm) LO: .5W (50 Ohm)
Input Sensitivity: 0.6V RMS for full output
Input Impedance: 47K
Output impedance: 1.2 Ohms
Preamp Output Impedance: 50 Ohms
Gain: 18dB (8 Ohm load)!
Noise: -94dB
Frequency Response: +0, -0.5dB, 6Hz-60kHz (8 Ohm Load)
THD: 0.5%
Input Voltage 110/220 Selectable
Tube Complement: (4x) 12AU7, (2x) 12AT7, (4x) EL84
Size: W: 16” (40.6cm), H: 5.125: (13cm), D: 16” (40.6cm)
Shipping Weight: 18 lbs (8.2kg)

Quick Start
Remove Z10i from the box.
Attach the power cable to the IEC connector and plug into an
outlet. Turn the power switch next to the IEC connector on. This will
not turn the Z10i on (unless you have Power-on Override turned on,
which you can do in the menu).
Hook up your sources and speakers.
Once your system is set up and everything is hooked up, turn on
your Z10i via the power button on the front panel. The buttons are
capacitive, so you only need to touch them, they do not push in.
There is a turn-on delay of several seconds to allow the unit to
warm up.
It is usually best to turn your components on starting from the
beginning of the signal path and ending at the amplifier, and to
turn your system off in reverse order.
Operation
The unit is designed to be powered on indefinitely without harm.
The front panel power button powers down the amplifier but the
power supply remains on in a nearly idle state. To turn the amp
completely off, use the power switch next to the IEC connector.
The unit is air cooled and should be placed somewhere with
adequate ventilation.

The front of the Z10i has the power button, IR sensor, volume knob,
tape and phono LEDs, input status LEDs, input selection button,
tape monitor button, menu navigation buttons, display,
headphone outputs, and headphone/speaker switch.
The back of the Z10i features the IEC connector, power switch,
tape in, tape out, four sets of RCA inputs, one set of XLR inputs,
and four binding posts.
Inputs
There are five total inputs: four RCA and one XLR. The XLR provides
a tube-coupled balanced input. The preampfification stage
converts the balanced input into a single-ended signal that suffers
no voltage loss.
Outputs
The speaker outputs use binding posts that allow you to use
banana plugs, spades, or bare wire.
There are two headphone outputs: one “HI” and one “LO”. These
refer to the output power, not the impedance. Use the HI output
for full-sized headphones that need more power and the LO
output for more sensitive headphones. Each uses a 1/4” jack.
There is a switch to use either the headphone outputs or the
speaker outputs. Always lower the volume before switching
between the two.
!
Tape Monitor
When Tape Monitor is selected via the button on the front panel,
the selected input sends an unattenuated signal directly to the
Tape Output and the Z10i outputs the signal from the Tape Input."

User Interface and Controls
The front panel features a power switch, input switch, volume
knob, and display. The remote control is able to adjust volume,
mute, and access a menu with more configurable options.
Remote Control
Up and Down Buttons: Volume Up and Volume Down. They can
be held down or used in a single step mode. In Menu mode, they
scroll up and down.
Left and Right Buttons: Unused unless activated in the menu to
function as Balance control or input selectors. In the Menu, they
act as selectors.
Center Button: Mute. When the unit is muted, there are two Xs on
the display. When in Menu, it acts as a Select button.
Menu Button: Enters Menu Mode. In the menu, this functions as a
Select button.
Play/Pause Button: Toggle inputs. [When held down for 30 seconds,
it will pair an Apple remote to the unit. Pairing confirmation
appears on the display when this is successful.]

Menu
The menu is accessed via the remote control or the buttons on the
front panel. Scroll with the up and down buttons to see menu
options. Pause on an option to see the entire title scroll by.
Balance: Use the right and left remote buttons to adjust the
balance. The front panel displays the balance setting as you
adjust - two bars in the center indicate that the balance is at 0
(both channels are equal). When the desired balance level is
selected, press the center button to save the setting. A message
will appear on the display to indicate which setting the balance
has been set to. The balance setting is saved across all inputs and
will be utilized upon power up to the last saved setting. The
maximum balance setting is 16 levels difference.
Brightness: The front panel display can be set to 16 levels of
brightness. The brightness levels are saved and recalled upon
power on.
Home Theater Input: Home Theater Input locks a selected input at
a fixed volume level to allow external volume control. Select the
input desired to have a fixed volume. This setting is saved and the
selected input will henceforth be locked at that volume level until
the Home Theater mode is removed from that input.
Display Timeout: The volume display and input LEDs can be set to
turn off after 10 seconds. They will reappear if a button on the
remote control is pressed or the volume knob or front panel switch
is changed. There are 3 settings:
OFF - The volume display and input LEDs remain on.
VOL - The volume display turns off but the input LEDs remain on.
ALL - The volume display and input LEDs turn off.
L-R Remote Arrows: There are two functions that can be selected
for the Left-Right Arrow buttons as follows:
Off – the remote Left-Right arrow buttons are deactivated.
BAL – the remote Left-Right arrow buttons will control the balance.
Inp – the remote Left-Right arrow buttons will select the input.

Power-On Override: When activated, the unit powers on when the
AC power is turned on without needing push the front panel
power button.
Reset to Default: The amplifier controls are set to Balance = 0,
Display Timeout = Off, Home Theater Mode = None, and Display
Brightness = 8, and Remote Left-Right Arrow buttons set to Not
Active.
Tubes
The Z10i is supplied with selected vintage tubes. The tubes operate
at low current, which allows them to have an extended life.
Changing tubes:
EL84: The power tubes are self-biasing and do not need to be
matched for gain.
12AT7: The 12AT7s should be a matched pair.
12AU7: These are used in the preamp section (the smaller circuit
board) and in the power amp section. In both cases, the 12AU7s
should be matched pairs and each individual tube should have
both of its triode sections matched as well.
The sockets are tight, so gently rock the tube pins until you are
able to remove the tubes. We use high-quality ceramic tube
sockets with gold pins which are designed in such a way that the
white ceramic part may shift slightly. This is an intentional design;
the tube socket is very secure.
Before changing tubes, turn off the amplifier and wait at least 10
minutes to allow the stored power to discharge. Avoid touching
any of the components on the circuit board, especially the
vertical circuit boards.

Note on using 7062 tubes:
The 7062 is often used as a replacement for the 12AT7. This is
usually not a problem, but they do require slightly more heater
current than a standard 12AT7, which in turn requires slightly less
current than a standard 12AU7. If you want to use 7062 tubes in
the power amp section, you’ll need to replace both the 12AT7s
and the 12AU7s with 7062s in order to ensure that all tubes receive
adequate heater current. You can use 7062s in the preamp
section without changing any of the other tubes.
Fuses
There are two 5x20mm 4A Slow Blow fuses in the IEC inlet of the
Power Supply.
For more information and FAQs, please visit
www.lineartubeaudio.com or contact us at
[email protected].

NOTES