Linear Tube Audio Z10 Seriers User manual

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2345%5/6 For$safety,$the$cover$of$this$ampli3ier$should$be$secured$at$all$times.$DC$
voltages$as$high$as$450V$and$peak$AC$voltages$as$high$as$800V$are$present$inside.$The$
service$information$contained$in$this$manual$is$intended$only$for$trained$service$
personnel.$
The Linear Tube Audio Z10 Integrated, or Z10i, is a full size and function, high
quality, Class AB integrated preampli;ier, headphone and speaker ampli;ier utilizing
ZOTL (Zero-hysteresis Output Transformer-Less) technology. There are 5 inputs (4
single ended RCAs and 1 XLR Balanced), 2 preampli;ier outputs, a remote control
and front panel controls, and a front panel dimmable LED display. There will be an
optional phono preamp in the future.
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7:<(*$%&6 The unit operates in both 115V 60hz and 220-240V 50Hz, but has to be
con;igured at the factory. The unit should be wired for your country when you
receive your unit from the factory.
%&=0'.6 There are 5 inputs to the Z10 Integrated. Four are single ended RCA stereo
pairs. One is a true balanced dual XLR stereo pair. Connect your DAC, CD player,
Phono Preamp or other line level device to these inputs.
>+=($?:&1':*$%&$+&,$@0'6 Whatever Input (1 thru 5) is selected is always present at
the Tape Out connector. This is true even when listening to the Tape In. The Tape
Monitor switch selects whatever is being sent to the Tape In connector. This is
typically a Tape Recorder playback output, but can be used with any device’s line
level output.

Z10 Integrated User Guide
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The Z10 Integrated utilizes front panel switch controls and a remote control. The
menu functions can be accessed from the front panel switches or by using the
remote control. The power on-off and input selection can only be performed by
using the front panel switches.
7:<(*$B0'':&6 The ampli;ier is ;irst powered on by the Power switch on the rear of
the unit. Turning the rear power switch activates the power supply but not the
ampli;ier circuitry. The user then touches the front panel Power switch to activate
the ampli;ier. There is a 30 second warm up time for the tubes and the front panel
display will display a message “warming up”, which upon completion, displays the
current volume setting.
C:80D($9:&'*:86 The volume can be turned up or down by turning the ampli;ier’s
volume knob clockwise or counter-clockwise or pressing the up or down button on
the remote. There is a clicking sound when the volume is changing that comes from
the relays controlling the volume level. There are 99 levels of volume. Whenever the
volume is changed, the volume setting is saved. Each input independently saves the
last used volume setting.
%&=0'$9:&'*:86 The Input button is a touch button that toggles through each of the
inputs and displays which input is selected using the input LEDs on the front panel.
The remote right and left arrow buttons can be con;igured to perform the input
button function using the remote. The remote must be con;igured to operate this
way – see the front panel menu functions.
>+=($?:&1':*6$The tape monitor touch button toggles the tape in rear panel input
with the normal inputs 1 thru 5. When the tape in is on and being heard on the
ampli;ier output, the tape out rear panel connection is still outputting the selected 1
thru 5 input. The tape monitor LED is illuminated whenever the Tape In input is
selected.
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Z10 Integrated User Guide
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There are two headphone jack takes a standard ¼ inch stereo phone plug. One is
limited to about 1 watt and is labeled “Low” and the other is about 3 watts and is
labeled “High”.
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The front panel menu is accessed by selected by Menu button on the remote control.
There are several menu functions. The menu selections can be seen by using the up
and down remote buttons. When the desired menu function is displayed, use the
center button on the remote to enter the desired menu.
G+8+&;($9:&'*:86$The volume attenuator has 99 steps for each channel. Balance is
achieved by creating a numerical offset which is applied to the volume steps
between the channels. The offset is stored in memory so that the ampli;ier can
automatically apply the balance offset when the ampli;ier is next powered on.
To enter balance mode, press the Menu button on the remote control. Press the
remote control center button to enter Balance. While in balance mode, using the
right and left remote buttons. The front panel display will add a bar for each button
press that indicates the balance increase and channel increased. Only two bars lit
indicates the balance set to zero. The ampli;ier re;lects the balance change as it is
set. When the desired balance level is selected, press the remote control center
button to save the balance 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.
H1.=8+I$J(''1&)6 There are 16 levels of brightness the Front Panel Display can be set
to. The brightness levels are saved and recalled upon power on. Scroll through the
brightness levels and press the Select button or the remote center button to select
the desired brightness. A message should scroll by con;irming the level you selected.
E:D($>F(+'(*$?:,(6 Home Theater mode locks a selected input to a ;ixed volume
level. Once set the volume control is locked for that input. The expectation is the
user will connect their home theater receiver to adjust the volume level and to
expect a ;ixed volume level from the Z10 Integrated. Enter the Menu mode as above,
scroll down using the up and down arrow keys to the Home Theater selection. Use
the remote control center button to select Home Theater mode. Then select the
input desired to have a ;ixed volume. This setting is saved and the selected input will
henceforth be locked at that volume level until the Home Theater mode is removed
from that input.
H1.=8+I$>1D(:0'6 The Display and the Input LEDs can be set to turn off after 10
seconds, and then will come back on if a button on the remote control is pressed or
the volume knob or front panel switch is changed. There are 3 settings:
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Z10 Integrated User Guide
Display Only - where the Display times out, but not the Input LEDs
Both - where both the Display and Input LEDs timeout, or
None - where the Display and Input LEDs are always on
4(.('$':$H(K+08'6 The ampli;ier 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.
4(D:'($L(K'M41)F'$3**:<$G0'':&.6$ 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. Prevents
accidental selection
Balance – the remote Left-Right arrow buttons will control the balance
4(D:'($7+1*1&)6 The unit uses the Apple TV remote commercially available through
Apple and their distribution. The remote sent with the unit will already be paired to
the unit and this function does not need to be performed. In the event that the user
wants to use a different Apple TV remote, it can be paired by holding down the
remote control Play button for approximately 30 seconds until a message appears
on the display indication the remote is now paired to the ampli;ier.
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Z10 Integrated User Guide
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There are two modes, the normal operation mode and the Menu mode, when
con;iguring your unit inside the Menu functions:
The buttons are as follows:
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-=$+&,$H:<&$G0'':&.6 These normally function as Volume Up and Volume Down.
They can be held down or used in a single step mode. In Menu mode, they function
to move up and down in the menu as displayed on the operator display.
L(K'$+&,$41)F'$G0'':&.6 In the normal operation mode these do not do anything.
They can be con;igured in the Left-Right Remote Button Menu to function as the
Balance control. In the Menu mode, the Right button is Select and the Left button is
Back.
9(&'(*$G0'':&6 This normally functions as a Mute function. When the unit is muted,
there are two Xs on the display. The Center button is a Mute toggle. When in Menu
Mode, the Center button functions as a Select button.
?(&0$G0'':&6 When in normal operation, selects the Menu Mode.
78+IN7+0.($G0'':&6$ When in normal operation the Play/Pause button toggles
through the Inputs. When in Menu mode, it also has no function assigned. Holding
the Play/Pause button for 30 seconds will pair a new Apple remote to the unit, but
this is only done in the event of replacing the remote.
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Z10 Integrated User Guide
>0B($9:D=8(D(&'6 The Z10 Integratedutilizes, and is shipped with, two 12AT7
input tubes and two 12AU7s and four EL-84 power tubes or equivalents.
>0B($4(=8+;(D(&'$+&,$>0B($4:881&)6 The Z10 Integrated utilizes the ZOTL
technology which operates the tubes at 1/3 the heat than other tube ampli;iers and
subsequently the tube life is typically 3 times as long as other ampli;iers. Unused
tubes will typically last 10,000 hours of operation.
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;:O(*$(&.0*($'F($=:<(*$;:*,$1.$,1.;:&&(;'(,P$$G($(Q'*(D(8I$;+*(K08$':$(&.0*($
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NOS (New old stock) tubes are available and almost always sound better than
Russian or Chinese tubes in current production. However, where these tubes have
been for the last 50 years is never certain, so sometimes they can fail or become
noisy (static or rushing sounds), and require replacement. And of course, one can
develop an af;liction known as “tube rolling”. As the ampli;ier sound will change to
re;lect the quality and “tone” of the tubes installed in it, some are often changing
between different brands to optimize the sound to their taste. In extreme cases,
adapter sockets are utilized to use exotic tubes not directly electrically compatible.
The ampli;ier has a powerful autobias circuitry, which means the ampli;ier
automatically adjusts to the optimal levels for the tubes and no adjustments are
required.
When replacing the tubes, the two labeled 12AT7 ones are the input tubes. They
must be matched so that the gain of each channel is the same (you could possibly
correct for unmatched tubes using the balance control).
The power tubes typically do not have to be matched in gain.
For the input tubes, any 12xxx equivalent tube can be used. Typically 12AT7s are
used (they have a gain of 60). There are many variants like 6201s, 5751s, 5814s, etc.
that all work well and if one set of tubes sounds better, use it. Note,$we$often$ship$
from$the$factory$with$4$7062$tubes$in$the$12AU7$and$the$12AT7$position.$If$you$want$to$
change$one$set$to$12AU7$and$12AT7s,$you$must$remove$all$four$7062s.$The$7062s$
cannot$be$intermixed$with$12AU7s$or$12AT7s.$
When$removing$the$tubes,$use$a$gentle$rocking$motion$as$you$pull$out$the$tube.$$When$
replacing$in$the$socket,$make$sure$the$pins$are$straight$and$aligned$correctly$with$the$
hole$pattern.$
Tubes sometimes develop tube noise. With no input to the ampli;ier connected, you
should not hear any static or rushing sounds. Sometimes tubes will make a little
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Z10 Integrated User Guide
noise as they warm up, as this is normal, but should disappear after a couple of
minutes.
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Z10 Integrated User Guide
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The ampli;ier is self-biasing, and has no adjustments.
The ampli;ier operates the tubes in a manner that maximize tube life, typically 3
times tube ampli;iers that do not have ZOTL technology. The tubes are expected to
give 10 to 20 years of service based on several hours of use per day. See the section
on Vacuum Tube Replacement.
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The Z10 Integrated has two fuses of the 5x20mm type slowblow, rated at 4A, in the
AC power input assembly.
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The ampli;ier comes with high quality tubes. Changing or “rolling” the tubes must be
done carefully so as not to damage your ampli;ier. If you choose to change the tubes,
be extremely careful to ensure the unit is off for at least 5 minutes to allow voltages
to dissipate. Avoid touching the board, as high voltages may still be present even if
the unit is off. Ensure the pins of the tubes are aligned with the tube socket. The
ampli;ier is self-biasing, so there are no adjustments necessary. Any damage caused
by changing the tubes is not under warranty.
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If the amp is not turning on immediately after going into protection, turn it off and
wait 30-45 minutes before trying again. Occasionally the circuit takes longer.
If you’re experiencing distortion immediately and cannot identify the source, look
for components in the source chain that may be leaking DC, such as power supplies.
The Z10 Integrated does not have a capacitor at the input to ;ilter DC (in order to not
compromise audio quality), so is susceptible to such leaks. If you do identify
something that is leaking DC (when taken out of the chain, the distortion should
disappear) and would prefer to keep it, we can install a capacitor at the input of your
Z10 Integrated.
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In 1996 David Berning developed a new and technically advanced vacuum tube
architecture designated as ZOTL. ZOTL stands for Zero-Hysteresis Output-
Transformer-Less ampli;iers. The ZOTL architecture eliminated the problematic
sound quality issues that audio-output transformers caused, as well as provides
many other advantages such as better frequency response and accuracy, longer tube
life, less tube heat and far better coupling from the tube to the output device.
The ZOTL ampli;ier uses radio frequency to change the voltage-current transfer
characteristics of the output tube from its normal impedance plane to one suitable
for driving a dynamic loudspeaker (or headphones and power ampli;iers). The
radio-frequency remapping is implemented using special high-frequency power-
conversion techniques. The high-voltage, low-current tube impedance plane is
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Z10 Integrated User Guide
remapped to the high-current speaker impedance plane through special
transformers operating at a constant RF carrier frequency of 250kHz. Because the
audio signal is riding on a carrier, it is not subject to parasitic elements of the
transformer that would distort the audio signal. Unlike the conventional audio-
output transformer, this impedance transformation operates on both the ac and dc
components of the signal.
In the transformer-coupled ampli;ier, the turns ratio of the output transformer
determines the impedance matching between the output tube(s) and the speaker.
With output transformers, there are practical limits to how large this ratio can be
made because of the parasitic elements of the windings, and it is dif;icult to make an
output transformer with more than a 25:1 ratio.
With the ZOTL technology, the impedance matching is determined by the effective
turns ratio of the RF converter transformers (called impedance converters). Without
the parasitics to affect the audio, these impedance converters can have much higher
effective ratios, opening the door to using various tubes under unusual operating
conditions that cannot be implemented with output transformers.
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Z10 Integrated User Guide
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Specifications (Typical Performance Values)
• Sensitivity: 1.2V RMS for 12 watts output
• Inputs – 4 Stereo Pairs Single Ended RCA, 1 Stereo Pair of 3 pin XLR balanced inputs
(true balanced)
• Outputs One set of speaker outputs, one Tape Monitor output, 2 Headphone Outputs
(High 3 watts, and Low 1 watt)
• Output impedance 1.2 ohms
• Input impedance: 50k
• 110V-120V / 220-240V operation: factory configured
• Hum and noise: 94dB below full output (measured at 20Hz-20kHz)
• Carrier: -50dB
• Power output with 4-ohm load: 13W, 0.5% THD
• Power output with 8-ohm load: 12W, 0.5% THD
• Frequency response (8-ohm load): 6Hz to 60kHz, +0, -.5dB
• Amplifier class: Push-pull Class AB
• Voltage gain (8-ohm load): 18dB
• Size: 17 inches (33.2 cm) wide, 5.25 inches (13.4 cm) tall, 14.4 inches (36.5 cm)
deep (including connectors)
• Net weight: 13 lbs. or 5.9 kg
• Finish: Aluminum case
• Tube complement: two 12AT7s, two 12AU7s, and four EL-84s or equivalent
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