OAD Ultrafidelity Padma User manual

Owner’s Manual
OAD
Ultradelity
Padma
Stereo Control Preamplier

Secon Page No.
Introducon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Venlaon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Interconnect Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Remote Control Operaon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Powering Up or Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Selecng an Input Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Adjusng Volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Mute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Idencaon of Connecons & Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3, 4
Descripon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Main Power On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Operang Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4, 5
Standby Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Balance Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Line Stage Specicaons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Contents

1
Introducon
Thank you for choosing the Padma to be a part of your high performance music listening system. Each
Padma is handcraed, using the very latest, no compromise, cung edge technology and componentry.
This ensures the best possible sound reproducon currently available and guarantees many years of
listening enjoyment.
We understand that you are eager to begin listening; however, please take a few minutes to read through
this guide for useful informaon concerning the operaon of your new preamplier. OAD Ultradelity
equipment takes a considerable me to run in before it performs at its best. The duraon varies, but
under some condions the sound may connue to improve for over a month. Beer and more consistent
performance will be achieved if the system is le switched on for long periods. It is worth remembering
however that equipment le connected to the mains can be damaged by lightning.
Aer reading this manual, if you have any further quesons regarding your preamplier, contact your
dealer or OAD Ultradelity customer service – they will be happy to help you to make the most of your
new component.
Happy Listening!
Warnings
• To prevent re, or shock hazard, do not expose your Padma to rain or moisture.
• Do not place objects containing water on top of this unit.
• This unit contains voltages which can cause serious injury or death.
• Do not operate with covers removed. Refer servicing to your authorized OAD Ultradelity dealer or
service personnel.
• A power cord is shipped with your Padma that meets the required safety standards. It is important for
both safety and performance that the standard cable supplied is not modied.
• A switch at the rear of the Padma must be accessible in case of emergency power disconnect. The
power buon on the front touch display panel of this unit, when o, does not disconnect all power
from this unit. This unit is in standby mode when not on. For connued protecon against re hazard,
replace the fuse only with the same type and rang (see page 8 for fuse informaon).
• Your hi- system, including the Padma, can be damaged by lightning and should be turned o and
disconnected from the mains when there is risk of lightning strike.
• We recommend that all connecons to the Padma are made with either the mains power cord
disconnected or the rear mains switch le in the ‘0’ (OFF) posion. When all connecons are made
and checked, move the rear mains switch to ‘1’ (ON) posion.
Venlaon
Due to its highly sophiscated numerous power supplies, the Padma will run slightly warm when not in
standby. You must allow for this in installaon, by providing for free air circulaon around the product.
Never block any venlaon openings. Allow at least 50 mm of clearance around these products for proper
venlaon. Electronics should not be subjected to sources of excessive radiant heat. Excessive heat can
shorten the life of the product.
Packaging
Save all packaging in a dry place away from re hazard. Your Padma is a precision electronic instrument
and should be properly boxed any me shipment is made. It is very unlikely that you will have to return
your unit to the factory for service, but if that should prove necessary, the original packaging will protect
your Padma from unnecessary damage or delay.

2
Interconnect Cables
XLR(Balanced) & RCA(Phono) Interconnect plugs and sockets should be kept clean and free from corrosion.
The Padma is ed with gold plated input and output sockets that may tarnish over me.
If you wish to clean the connectors, switch o the equipment, pull the plugs out of their sockets, and push
them back in again. Contact cleaners and “enhancers” should not be used as the lm they deposit may
leave a deposit and degrade the sound.
POWER
SOURCE
VOLUME
MUTE
IR Remote Control Operaon
When operang the remote control the RED LED will blink
repeatedly to show that an IR signal has been sent. If the LED
does not light when any of the buons are pressed then the
baery will need to be replaced by unscrewing the lower two
screws on the remote control rear.
Powering Up and Down
So long as mains power is applied the remote control can be
used to power up or down the Padma. The last preset you have
used will be engaged (as indicated by the LED above the buon).
Selecng an Input Source
The group of six source input buons on the front panel can be
selected using the remote control buons. Pushing the source
up or down buon will engage the associated input.
Adjusng Volume
The volume up/down buons operate as they do anywhere else.
The LED on the volume knob will come on to provide easy visual
feedback of the volume seng. Volume steps in 0.5dB steps.
Mute
The boom buon toggles the mute funcon. In mute mode
the volume knob LED will ash every 3 seconds.

3
OAD Preamp Rear Panel Hole Cutouts
Date: 26 Oct 2020
Rev:1
10.0
4.0 R2.0
R2.0 Ø22.0
Ø3.2
19.8
19.8
Rounded Rectangle
XLR
Input 1 Input 2 Input 3 Input 4 Input 5 Input 6 HT
Outputs
Main
Outputs
BAL
SE
Remote
Outputs
OAD Ultrafidelity P/L Padma Preamplifier Designed and Handcrafted in Australia
R
L
BAL
SE
BAL
SE
!
Risk of Electric Shock
Do Not Open
CAUTION
Idencaon of Connecons & Controls REAR PANEL
1 AC MAINS INPUT
• The Padma comes supplied with a detachable mains power cord. Connect corresponding end of the
mains power cord to the AC mains input of Padma and the plug connected to a mains power source.
• Always disconnect the mains power plug from the mains power source rst, before disconnecng the
cable from the Padma’s AC Mains input socket.
2 POWER SWITCH
• Supplies the AC mains power to the Padma.
• When the POWER switch is set to ON (1) posion, the Padma will run through its calibraon procedure
and within 60 sec will be ready to play.
• If you do not intend to use the Padma for long periods of me (such as when on holidays), switch o
(0) the POWER switch. With POWER switched o, the remote control’s power buon cannot acvate
the Padma.
3 FUSE HOLDER
• Your Padma is ed with a fuse. If it needs to be replaced you must use the same type and rang.
Installing an incorrect fuse may cause damage and this will void the warranty of your Padma.
4 AUDIO OUT
• The main outputs that connects the Padma to the corresponding audio inputs of external power
ampliers. Both single-ended (SE) and balanced (BAL) outputs are provided.
5 AUDIO IN
• Use single-ended or balanced analog audio input for sources (CD Player, tuner, DAC or other applicable
devices). Inputs 1, 2 and 6 have SE and BAL opons, whereas Inputs 3, 4 and 5 have only SE inputs.
•
6 SE & BAL SELECTION
• Depending on whether you choose SE or BAL, set the toggle switch to the corresponding input.
7 HOME THEATRE OUTPUTS
• Connect a source that you wish to use for both your Stereo and Home Theatre to Input 6. Either SE
or BAL inputs are accepted. Connect the HT Outputs, either SE or BAL to your corresponding Home
Theatre amplier inputs. When the Padma is in operaon the HT Outputs are disconnected. When the
Padma is placed into standby the HT Outputs will connect the source inputs at Input 6 to your Home
Theatre amplier.
6
2 31
4
5
8
7

4
Idencaon of Connecons & Controls FRONT PANEL
8 REMOTE OUTPUTS
• The two trigger outputs can be used for various purposes. The most obvious one is making the power
amplier (stereo or mono) turn on and o with your preamplier. Any standard 3.5mm jack/jack
cable will do (mono or stereo). The factory seng is to make both outputs come on as soon as the
preamplier is turned on.
Volume Control
Source Selecon Buons
Source Selecon Indicator
Descripon
Mains power on
At power on the amplier enters a one-me calibraon and self-test roune. During this process none of
the front panel LEDs are illuminated. The calibraon and self-tests are for the volume knob mechanism.
The rst part nds the posion of the minimum and maximum end-stops and checks the range of moon.
The second part traverses the complete range of moon and calibrates the volume knob posion sensor.
The third part rotates the volume knob to the maximum volume posion and then visits each volume
posion performing a check on the sensor calibraon.
Should the power-on diagnoscs fail the knob will be powered o and all the front panel LED’s will ash.
At the end of power on self-test the volume knob will be at the minimum volume posion and the
amplier will come out of standby, powering up the power supplies, connecng input sources. The power-
up process takes approximately 30 seconds and when complete the front panel LED for channel 1 will be
illuminated. At this point the amplier is ready for use with input channel 1 selected at minimum volume
level and is in operang mode.
Operang mode
In operang mode, the owner can use the amplier as intended, enter standby mode or balance control
mode.
The input audio channel can be selected by either pressing the front panel input buon or by using the
channel up/down buons on the remote control. The current input channel will be indicated by the
front panel channel LED. The input channel change from the remote requires one buon press at a me
to increase or decrease the input channel. The channel change does not have an auto-repeat funcon.
When the input channel is 1 pressing channel down on the remote will not change the input to channel
6, i.e., it does not wrap round. The same is true when input channel 6 is selected and channel up is
pressed.

5
Operang mode cont.
Volume control can be performed by either moving the physical volume knob by hand or by using the
volume up/down buons on the remote control. A single press of the volume up/down buon will increase
or decrease the volume by 0.5dB. Pressing and holding the volume buons will inially change the volume
by 0.5dB and aer holding the buon for greater than 1 second will cause the volume to connuously
increase or decrease for as long as the buon is held down. Volume change by hand or by IR will cause the
indicator LED in the knob to light for 1.2 seconds.
The volume knob has detents at each of the 144 volume posions. The detents are performed in soware.
The volume can be muted using the mute buon on the remote control. Each buon press toggles mute
on and o. There is no provision for applying mute from the front panel. When mute is acve the knob
LED ashes briey once every 3 seconds. In mute the IR volume change is inhibited however the volume
can be changed by physically moving the knob and when exing mute, the volume will correspond to the
physical knob posion.
Standby mode
Standby mode is acvated by pressing the power buon on the remote control. In standby mode the front
panel LEDs are turned o, input relays disconnected and power supplies turned o. In standby mode the
unit does not respond to any IR commands other than the power buon. The front panel channel select
buons are also inacve. The volume knob can sll be moved by hand in standby mode and if it is, when
the amplier comes out of standby the volume level will be whatever corresponds to the posion of the
volume knob. The state of mute is remembered and the mute state is remembered and restored on exit
from mute.
Standby mode is exited by pressing the IR power buon. This will start the power up sequence which takes
a while. During the power up sequence all front panel LED are on unl operang mode is reached.
Balance mode
Balance seng mode is acvated by pressing and holding the CURRENT selected input channel buon for
3 seconds. During balance seng mode the volume knob becomes the balance seng indicator. The knob
will rotate to the posion corresponding to the current balance seng. 12’oclock is centre balance. 6dB
le is at 9’ockock. 6dB right is at 3’oclock.
When the knob has reached the current balance posion the knob LED will illuminate and remain on.
Balance can be changed by manually moving the volume knob. Detents at each balance posion are
provided by soware. Should the knob be moved past the 9’oclock to 3’oclock posion no more detents
will be felt and the knob will apply a connuous torque back to the 3’oclock or 9’oclock posions.
IR CHUP/CHDN change the balance in 0.5dB steps. VOLUP/VOLDN change the volume in 0.5dB increments
and holding down the volume buon for more than 1 second will acvate volume autorepeat. A change
in balance or volume will be indicated by the knob LED ashing o briey. During volume autorepeat the
LED remains o for the duraon.
IR mute applies mute. When muted, IR volume up/down is inacve. In mute the knob LED blinks o briey
every 3 seconds.
Any front panel buon or IR POW will exit balance mode back to operang mode.
At exit of balance mode the balance seng is stored in EEPROM so the seng is remembered across
power cycles.

6
Line Stage Specicaons
Input Sensiviy: 80mV
Main Output Level (SE): 0.775V
Main Output Level (BAL): 1.55V
Maximum Output: >20V RMS or 28.2 dBu
Frequency Response: 0 - 650kHz -3dB @ 1.8VRMS Output
0 - 280kHz -3dB @ 20VRMS Output
Input impedance: 20k Ohms
Output impedance: (SE) < 47 Ohms and (BAL) < 100 Ohms
Total Harmonic Distoron: < 0.001% @ 100mV output 20Hz -20kHz
Signal to Noise Rao: >110dB A-weighted input shorted
Overload Margins: 40dB (all inputs all audio frequencies)
Gain Range: -62dB to +10dB
Gain Resoluon: 0.5dB
Mains Fuse: Model 220-240V 1A/250V an surge (T) M205
Model 100-120V 2A/250V an surge (T) M205
Weight .................................. 13 kg (15.5 lbs)
Shipping Weight ................. 14.6kg (18.96 lbs)
Dimensions .......................... 126(H) x 438(W) x 353(D)mm (4.96” x 17.25” x 13.9”)
Shipping Dimensions ........... 235 (H) x 570 (W) x 500 (D) mm (9.25” x 22.44” x 19.68”)
Mains Supply ....................... 110-120V or 220-240V, 50/60Hz
Warranty
OAD Ultradelity products are covered by a 3-Year Limited Warranty. This Limited Warranty iniates from
the date of purchase, and is limited to the original purchaser. Outside Australia, the authorized imporng
retailer or distributor has accepted the responsibility for warranty of OAD Ultradelity products sold by
them. The specic terms and remedies for fullment of the Limited Warranty may vary from country to
country. Warranty service should normally be obtained from the imporng retailer or distributor from whom
the product was purchased. In the unlikely event that technical service beyond the ability of the importer
is required, OAD Ultradelity will full the terms and condions of the Limited Warranty. Such product
must be returned at the purchaser’s expense to the OAD Ultradelity factory, along with a photocopy
of the dated purchase receipt for the product, a wrien descripon of the problem(s) encountered, and
any informaon necessary for return shipment. The cost of return shipment is the responsibility of the
purchaser.
All technical specicaons are subject to change without prior nocaon.

7
This Page Intenonally Le Blank

OAD
ultradelity
www.openaudiodesigns.com