Violectric DHA V226 User manual

HEADPHONE AMPLIFIER
with D/A onverter
Violectric DHA V226
USER´s MANUAL

2User´s Manual DHA V226, November 2021, F. Reim

User´s Manual DHA V226, November 2021, F. Reim 3
Content
Theme Page
About 4
Safety Instructions 6
The Earth / Grounding Concept 8
General 10
Block Circuitry 13
Operation: Power , Inputs 14
D/A Converters 16
About PRE-GAIN 16
Volume, Outputs 19
Headphone Connectors 20
Line Outputs, Pre / Post Setting 21
Error Reporting 22
Things to Know 22
Disposal 27
Technical Data 28
Dismantling, Jumper Settings 29
Conformity Statement 30
Warranty 31
CAUTION !!
THE HIGH OUTPUT LEVELS ACHIEVABLE
WITH THIS UNIT MAY
DAMAGE YOUR HEARING OR THE
HEADPHONES

4User´s Manual DHA V226, November 2021, F. Reim
Cordial thanks for your decision in favour
of a product !
is a trademark and product line of Lake People
electronic GmbH. Lake People electronic GmbH develops,
manufactures and distributes products in the professional range, for
broadcast, television, airports, exhibition halls, festival venues,
theatres, large-scale installations, private studios and more. In the
private sector as well, Lake People products become increasingly
popular due to their outstanding quality.
The trademark and product line is specially intended
to supply the Hi-Fi and High-End market with its specific
requirements.
Who develops equipment ?
The devices are exclusively developed in Germany by the engineers
of Lake People electronic GmbH. In doing so, the team of developers
can draw on over thirty years of experience and countless products
for the pro-audio domain.
Among others, the first German-made 20-Bit A/D and D/A
converters were developed by Lake People in the early nineties of
the past century.
Who manufactures equipment ?
The devices are exclusively manufactured in Germany by Lake
People electronic GmbH or contractors in the company's vicinity.
- put highLake People - and by association
emphasis on domestic manufacturing. As well, all component
suppliers are chosen in order to achieve the main part of added value
inland.

User´s Manual DHA V226, November 2021, F. Reim 5
How do devices get to the customer ?
The devices can be obtained from respective specialist suppliers. If
there is none such accessible regionally, the customer is supported
by transregional distribution partners (google may help...) and, of
course, by on-line shop.
…and if it doesn't work like it should ?
devices are covered by a 5-years warranty. In case of
any malfunction during this period, they can be shipped to the
manufacturer directly. Of course, the client will benefit from the full
technical support even when warranty has expired. Any technical
questions or need for advice is welcome.
is a subsidiary of
LAKE PEOPLE electronic GmbH
Turmstrasse 7a
D-78467 Konstanz
Fon [phone]
Fax [phone]
Mail: [email protected]
www.violectric.de www.violectric.com
www.lake-people.de www.lake-people.com

6User´s Manual DHA V226, November 2021, F. Reim
WARNING
For your protection, please read the following:
Water, Liquids, Moisture:
This appliance should not be used near water or other sources of
liquids. Care should be taken so that objects do not fall and liquids are
not spilled into the enclosure through openings.
Power Sources:
The appliance should be connected to a power supply only of the type
described in the operating instructions or as marked on the appliance.
Grounding:
Care should be taken that this appliance is operated with proper
grounding only.
Power Cord:
Power supply cords should be routed so that they are not likely to be
walked on or pinched by items placed upon or against them, paying
particular attention to cords at plugs, convenience receptacles, and
the point where they exit from the appliance.
This unit is equipped with a 3-pole mains cable with German 3-pin
mains plug.
In some countries this unit must be operated with a mains adaptor,
supplied by the owner.
Please refer to the table below to connect a mains plug:
U.K. Mains Plug Warning:
A moulded mains plug that has been cut off from the cord is unsafe.
Discard the mains plug at a suitable disposal facility.
OVERVIEW: POWER CORD FUNCTION AND COLORS
CONDUCTOR COLOR Alternativ
LLIVE BROWN BLACK
NNEUTRAL BLUE WHITE
E PROTECTIVE EARTH GREEN+YELLOW GREEN

User´s Manual DHA V226, November 2021, F. Reim 7
Mains Fuse:
The mains fuse of this appliance is soldered in place and accessible
from the inside only!!
A blown fuse may indicate an internal problem and should be
replaced during qualified servicing or repair work!
Switchable Power Supply:
Connect this unit to the power source indicated on the equipment
rear panel only to ensure safe operation!
This unit is provided with an internally settable mains supply
for 230 or 115 V AC.
Service / Repair:
To reduce the risk of fire or electric shock, the user should not
attempt to service the appliance beyond the measures described in
the operating manual. All other servicing or repair should be referred
to qualified personnel!
Electromagnetic Compatibility
This unit conforms to the Product Specifications noted as
Declaration of Conformity at the end of this manual. Operation is
subject to the following conditions:
- this device may not cause harmful interferences
- this device must accept any interference received,
including interference that may cause undesired operation
- this device must not be operated within significant
electromagnetic field
VOR DEM ÖFFNEN NETZSTECKER
ZIEHEN!! PULL MAINS BEFORE
OPENING!! AVANT D´OUVRIER
RETIREZ LA FICHE MALE!!

8User´s Manual DHA V226, November 2021, F. Reim
The Earth / Grounding Concept

User´s Manual DHA V226, November 2021, F. Reim 9
General GROUND-LIFT Jumper
(Accessible from the inside. Mind the SECURITY INSTRUCTIONS):
Ex-works this jumper is set to the LIFT position.
The internal ground potential is “lifted”by means of this jumper.
As a result, the interconnection for DC voltages and lower
frequencies (< 150 Hz) will be cut.
Higher frequencies will be bled off to earth potential through the RC
filter. The LIFT position is helpful in case of hum or jitter caused by
different ground/earth potentials. Of course, full electrical protection
is granted as the case is always connected to ground/earth
potential!
Electrical safety is always ensured, since the earth conductor is
permanently connected to the enclosure!
Please note that with jumpers not in the ex-works
position EMC emission might occur,
for which the user is responsible only!
So, only change these settings when you
know what you are doing!

10 User´s Manual DHA V226, November 2021, F. Reim
GENERAL INFORMATION
VIOLECTRIC DHA V226 contains an excellent D/A Converter, a first-
class Preamplifier and a high-grade stereo balanced Headphone
Amplifier designed to drive low-, medium- and high-Z loads
(16...600 ohms) as usually represented by high-quality headphones.
Because of its four built-in amplifiers and both front mounted
balanced headphone sockets (4-pin XLR and 4.4 mm Pentaconn) it is
a real balanced amplifier and the balanced socket are not only a
convenience feature.
Due to its specific, highly variable, low-noise and low distortion
circuit design especially optimised for dynamic and orthodynamic
headphones, DHA V226 fulfils even highest demands.
Features:
-2 analogue Stereo Inputs,
unbalanced via RCA sockets, gold plated
-1 digitale Input
USB-C, PCM, 32 Bit, 384 kHz, DSD 64 - 256
-all inputs switchable from the front
-LED displays for the activated input, PCM or DSD data
-32 Bit / 384 kHz CS43131 Digital-Analogue converter
-PRE-GAIN = 7-fold switchable gain/attenuation
-18 / -12 / -6 / 0 / +6 / +12 / +18 dBr
-Headphone amp with 4 discret-design power amps
with 16 transistors per channel
-extremly low output impedance
-1 x 4-pol XLR connector, Neutrik, balanced, gold plated
-1 x 4,4 mm Pentaconn, balanced, gold plated
-1 x 6,3 mm (1/4“) phone jack, Neutrik, unsymmetrisch
-Unbalanced stereo line output via RCA, gold plated
-Line output pre/post switchable
(fixed/variable –with / without volume control)

User´s Manual DHA V226, November 2021, F. Reim 11
-RK 27 volume attenuator
-Output management:
Headphones active / Line out active / none active (OFF/Mute)
-Display of the active output and „OFF“via LEDs
-Hochwertige MKP Kondensatoren im Signalweg
-High-grade MKP capacitors in the signal path
-0,1 % und 1 % Metallfilm resistors
-Large filter capacity > 22.000 uF
-delayed relay-based headphone output during power on
-instant cut-off for power off
-Protective circuits for DC and frequency range
-toroidal transformer 15 W
-Rugged Aluminum case, black anodized
-5 mm massive Aluminum front panel
With its dimensions, the VIOLECTRIC DHA V226 ensures optimum
flexibility combined with high output power. During design, high
emphasis was put on operational safety even when the unit is
operated inappropriately.
DHA V226 is equipped with safety circuitry and internal filters to
prevent damage to the connected headphones due to DC voltages
at the outputs and high-frequency overload beyond the audible
range
THE CASE
of VIOLECTRIC DHA V226 is made of 4 mm Aluminum and a thick 5
mm aluminum front panel. This choice of material ensures high
mechanical stability and resistance whilst maintaining a high
optical and haptic quality.

12 User´s Manual DHA V226, November 2021, F. Reim
GROUND AND PROTECTIVE EARTH
The case of VIOLECTRIC DHA V226 is connected to protective earth.
POWER SUPPLY
Mains power is provided via a three-pin IEC/CEE socket and mating
"cold-appliance" mains cord with Schuko-type plug for units
purchased in middle Europe.
The device is set to 230V mains, whereas the actual voltage may
vary between 190 and 240 volts for flawless operation.
The mains voltage may be altered to 115 V AC supply inside the unit
with the aid of a mains voltage selector. In this case stable operation
is granted in a range of 85 to 120 V (see page 30).
A toroidal transformer with 15 Watt is providing the internal
operating voltages of +/-25 V. Out of these voltages some more
operating voltages are generated.
MAINS FUSE
The 0.5A time-lag fuse is soldered in place on the circuit board. In
case, it must be replaced with a fuse of the same type only.

User´s Manual DHA V226, November 2021, F. Reim 13
Block circuitry VIOLECTRIC DHA V226

14 User´s Manual DHA V226, November 2021, F. Reim
THE POWER-SWITCH
The unit is put into operation by
means of the power switch.
The power-on procedure takes about
5 seconds.
During this time the “OFF”LED over
the “OUTPUT”switch lights red.
It turns off when all internal para-
meter are checked and found OK and
the “OUTPUT”switch is positioned to
"HEAD“or "LINE“position.
Any breakdown will cause the “OFF”LED to come up and the
outputs are muted.
THE ANALOGUE SIGNAL INPUTS
The unbalanced analogue sig-
nal inputs are situated on the
back of the unit. Gold plated
RCA sockets are provided.
They are labelled as "RCA IN L
1/2”and "RCA IN R 1/2".
The input impedance on all
analogue inputs is 10 kohms.
Maximum input level should not exceed +21 dBu. It is reduced to +3
dBu when PRE-GAIN +18 dB is engaged.
THE DIGITAL SIGNAL INPUT
is found on the unit's rear panel. The USB-C socket is specified
according to USB 2.0 - PCM signals up to 32 bit and up to 384 kHz as
well as DSD 64 –256 data is accepted here. The USB interface is in
no need of drivers for PCs Laptops, tables or smart phones.

User´s Manual DHA V226, November 2021, F. Reim 15
PRE-GAIN
These DIP-switches are situated
on the back of the unit inside the
field of the analogue inputs.
Settings can be made for the left
and right channel, they shall not
be different from each other.
With these switches an
additional gain or attenuation
may be set.
It is dependent on the output level of the input source and the
sensitivity of the headphones connected. By this measure it is
maintained to achieve lowest possible noise and maximum travel of
the volume attenuator.
The high gain/attenuation range of +/-18 dB (factor 64) ensures a
perfect match of any source with any headphone in the market.
Please see page 16 to learn more about:
“Too loud ? Too soft ? The PRE-GAIN method”
SELECTING / ACTIVATING AN INPUT
With the “INPUT“switch on the
front of VIOLECTRIC DHA V226 one
of two analogue inputs or the digital
input may be activated.
The corresponding LED is
illuminated.
Concerning the digital input, also
the “STATUS“LED displays green for
PCM signals or blue for DSD signals
as long as an appropriate digital signal was detected. When there is
no signal on these inputs or a non-valid signal, these LEDs will stay
dark and the outputs are muted.

16 User´s Manual DHA V226, November 2021, F. Reim
THE DIGITAL to ANALOGUE CONVERTER
(D/A Converter)
inside DHA V226 is the Cirrus Logic CS43131. It is a high performance
32-bit solution designed for Audiophile and Studio equipment
applications. PCM data up to 384 kHz and DSD 64 –256 is accepted.
The converter offers a typical dynamic range of 130 dB with THD+N
as low as -115 dB.
The internal frequency of the digital signal (and potential inter-
ference therein) is very high in comparison with the useful analogue
frequencies. Therefore, the subsequent analogue low-pass filters
have to meet less severe requirements in terms of high-frequency
roll-off and can be realized as "musical", discrete two-pole filters.
THE AMPLIFIER(S)
The input signals are fed to an amplifier stage especially designed for
this application, with 2 x eight transistors per channel. Because of
the true balanced operation VIOLECTRIC DHA V226 houses no less
than four of those! The channels are physically separated from each
other to ensure optimum crosstalk rejection.
The frequency range covers 5 Hz ... 250 kHz (-0.5 dB) in order to
ensure fully linear performance within the entire audible range.
Overall gain is set to +2 dB (unbalanced) or +8 dB respectively
(balanced) to ensure lowest self-generated noise.
Too loud ? Too soft ? The PRE-GAIN method
The VIOLECTRIC DHA V226 is specially designed to drive
headphones. To do so it is placed between up to three analogue or
one digital sources and the headphones. Headphones however can
present load impedances from 8 to 2000 ohms and efficiency ratios
from 85 to 115 dB per Milliwatt. The sources may have output levels
between 0.5 Volt up to 10 Volt. Thus, it can be quite tricky to fulfil all
demands, since...

User´s Manual DHA V226, November 2021, F. Reim 17
…owners of high-efficiency headphones will rarely set the volume
control higher than 9 o'clock in order to exclude hearing damage,
while
... the maximum setting may still be too soft for low-efficiency
headphones, but
…all users expect highest quality at lowest noise and distortion.
Thus, the circuitry must adapt itself - as the headphones won't do
and the sources will seldom do!
WE CALL THE SOLUTION TO THIS PROBLEM PRE-GAIN
A single amp of DHA V226 has only little gain (gain = +2,5 dB = factor
1,25). In case a balanced headphone is connected two amps are
active with a combined gain of +8 dB (factor 2,5).
By this measure the amps will produce an extremely low self-
generated noise which can hardly been heard even with highest
sensitive in-ear-monitors (IEM).
On the other hand, the amps of DHA V226 with very powerful
transformers and with their high operating voltage are able to drive
low efficiency or high impedance headphone to the full with ease.
You will hardly find a headphone driving DHA V226 to its limits. This
effortless action will save your precious headphones as they will
never see a distorted signal from the amp.
The alignment between amplifier and headphone is provided by the
preamp stage, which can boost or attenuate the input signal in seven
steps of -18 / -12 / -6 / 0 / +6 / +12 / +18 dBr. (Factor 64 !!) For this
purpose, two switching devices are located on the rear panel for left
and right channel individually.
HOW TO OPTIMIZE THE PRE-GAIN SETTING:
Connect your source to VIOLECTRIC DHA V226 and plug in your
headphones.

18 User´s Manual DHA V226, November 2021, F. Reim
Listen !!
Your amp is adjusted best by the individual PRE-GAIN setting when
the volume control for “normal”listening is positioned around
12 o´clock.
So it is provided, that there is enough attenuator travel to boost the
signal through lower level passages or to listen with higher volume.
On the other hand, the attenuator travel is optimized to reduce the
self-generated noise from the amp.
THE HEADPHONE AMP PRE-GAIN SETTING
Ex works all switches are in the lower position: 0 dB gain.
In case you cannot reach the 12 o´clock position because the input
signal is too loud, feel free to reduce the signal with the PRE-GAIN
steps -6 / -12 / -18 dBr (factor 0,5 / 0,25 / 0,125).
In case the signal is too soft even with volume settings above 12
o´clock please use the PRE-GAIN settings +6 / +12 / +18 dB to
achieve more gain (factor 2 / 4 / 8).
Other than the above settings are not useful but harmless.

User´s Manual DHA V226, November 2021, F. Reim 19
CAUTION
To avoid unwanted level leaps the settings should be altered under
the following conditions only:
-The "VOLUME" control should be set to minimum or the head-
phone outputs shall be deactivated using the “OUTPUT“switch.
-Left and right channel settings should be the same
unless you want to settle the amp for different hearing abilities.
Ex-factory, all switches are set to their lowest position - i. e. 0 dB
PRE-GAIN - which should be sufficient for most applications.
THE VOLUME
ATTENUATOR
is to set the desired volume
for the left and right channel
simultaneously.
DE /ACTIVATING THE
OUTPUTS
The "OUTPUT" switch offers
three positions.
Moving the "OUTPUT" switch to the "HEAD"
position will activate the headphone
outputs. The white LED shows the
activated state.
Moving the "OUTPUT" switch to the "LINE" position will activate the
rear line outputs. The white LED shows the activated state.
Moving the "OUTPUT" switch to the middle position will deactivate
all outputs (mute). The red LED shows this state.

20 User´s Manual DHA V226, November 2021, F. Reim
HINT:
To protect the headphones from interferences during powering
on/off the outputs are cut during powering on. This procedure takes
about five seconds, shown by the red LED over the “OUTPUT”
switch. When powering off the outputs are cut instantly.
BALANCED HEADPHONE OUTPUT CONNECTORS
DHA V226 offers two
dedicated headphone
outputs to connect
balanced headphones.
The outputs are
situated on the front
panel and come as a
4.4 mm Pentaconn
and a gold plated
4-pin XLR socket.
5-pol Pentaconn TRRRS Socket:
T (Tip) (+) Left channel
R1 (Ring 1) (-) Left channel
R2 (Ring 2) (+) Right channel
R3 (Ring 3) (-) Right channel
S (Sleeve) Ground
4-pin XLR Socket:
Pin 1 (+) Left channel
Pin 2 (-) Left channel
Pin 3 (+) Right channel
Pin 4 (-) Right channel