Trends Audio PA-10 User manual

TrendsPA-10Tube
Headphone/Pre Amplifier
Version 1.0
USER GUIDE
CopyrightNotice
Copyright 2006 ITOK Media Limited,Allrightsreserved.
All rightsin thispublicationarereservedandno partmaybereproduced withoutthe
prior writtenpermissionofthe publisher.The contentsof thispublicationare believed
to becorrectatthe timeofgoingtopress,butany information,specifications,products
orservicesmentionedmay bemodified,supplementedor withdrawnwithout further
notice.
Trademarks
Trends,Trends Audio,and ITOK are the trademarks owned byITOK Media Limited
All other trademarks arethe property of theirrespective owners.
ITOKMediaLimited
UnitE,13/F,WorldTechCentre,
95 HowMingStreet,Kwun Tong, Hong Kong.
Tel:[phone]
Fax: [phone]
Email:[e-mail]
http://www.TrendsAudio.com

Table OfContents 3
T
Ta ab bl le e O Of f C Co on nt te en nt ts s
TABLE OFCONTENTS.................................................................................................3
1. SAFETYINSTRUCTIONS........................................................................................4
2. INTRODUCTION......................................................................................................4
3. FEATURES...............................................................................................................5
4. OVERVIEW...............................................................................................................6
5. HINTS&TIPS...........................................................................................................7
6. SPECIFICATION.......................................................................................................7
6.1 SpecificationofthePreAmplifierUnit...............................................................7
6.2 SpecificationoftheHeadphoneAmplifier Unit..................................................8
6.3 SpecificationoftheACAdaptor........................................................................8
7. TROUBLESHOOTING.............................................................................................9
8. ACCESSORIES........................................................................................................9
9. COMPARISON........................................................................................................10
10.TECHNICALNOTES(FOR PROFESSIONALUSER ONLY)...............................10
10.1Jumper Settingfor DifferentTube Series.....................................................10
10.2DCBias Voltage Tuning...............................................................................11
11. REGULATORYCOMPLIANCE..............................................................................12
12.CONTACTUS.........................................................................................................12
TrendsPA-10 User Guide
Section 1.SafetyInstructions /Section 2. Introduction 4
1
1. . S Sa af fe et ty y I In ns st tr ru uc ct ti io on ns s
Pleasetake notethefollowinginstructionsbeforeinstallingyour Trends PA-10Tube
Headphone/Pre Amplifier,theywillenable youto get thebestperformanceand
prolong thelife of the product.
This unitmustnot be exposedtodripping or splashingwater orother liquids. No
objectsfilledwith liquid,suchas vases, shallbeplaced ontheunit.In theevent, switch
offimmediately,disconnectfrom the mainsupplyand contact yourdealerorusfor
advice
Do notroute the powercableso that itcan bewalkeduponordamagedby otheritems
near it.
Electronicaudio componentshavearunninginperiodofaroundaweek (if used
severalhours per day). Thiswillallowthe newcomponentstosettle down;the sonic
properties willimproveoverthis time
If youdonotintendto usethis unitforalong periodoftime,unplug it from main socket
Tocleantheunit,wipe itscase withamoist,lint-freecloth.Donot useany cleaning
fluids containingalcohol,ammonia or abrasives. Do notsprayanaerosolatornear
TrendsPA-10.
Theseunitsarenotuserserviceable,never attempttorepair,disassembleor
reconstructtheinit ifthereseemstobe aproblem. Aseriouselectricshock couldresult
ifthis precautionary measureisignored.Inthe event of aproblem or failure, please
contact your dealer orus
2
2. . I In nt tr ro od du uc ct ti io on n
Thank youfor purchasingaTrends PA-10Tube Headphone/Preamplifier
TrendsPA-10Tube Headphone/PreAmplifier is aninnovative audio product and
providesallfunctionsofheadphoneamplifierandpre-amplifier.It includesthe
innovativecircuitdesignof lowvoltagehybrid(tube/transistor)pre-amptoprovide
audiophilequalitysound,compact size,and easy/safeDIYeraccessibility -pure
class-Acircuitto providethebest soundperformanceandhavefuntube rollingwith
this fantastic headphone/Preamplifier

TrendsPA-10 User Guide
Section 3. Features 5
3
3. . F Fe ea at tu ur re es s
ltheinnovativecircuit designoflowvoltage hybrid (tube/transistor)pre-ampto
provideaudiophilequality sound,compactsize, andeasy/safeDIYeraccessibility
lpureclass-Acircuitto provide thebest sound performance
lsupport both6DJ8/6922 seriesand12AU7 series tubes bysimplyswitchingthe
jumpers.DIYers caneasilychange theirboth series tubes toenjoy the fun.
lONE bi-triode6DJ8/6922 or 12AU7 tubeas voltageamplificationandTWO
MOSFETsasoutputdriverwhichperformthewarm,comfortable tubesoundandin
addition,guaranteethehigh fidelity&sufficientdriving powerto thenextpower
amplifierstage.
lprovideallfunctions of headphone amplifier andpre-amplifier
lprovideTWOsetsofswitchable audioinputs.Besidesthe normalCDinput, the
PC/iProd inputwith higher gainisprovidedfor smalloutputphonoamplifieror
PC/Mac/iPod.
lBesides the normal audio output intheback panel,ONEheadphoneoutputinthe
fronttodriveeven high-impedance audiophile-grade headphones
lcompact design (mini-size &lightweight), suitablefor hi-firoom, living room,
sleepingroomor even rightbeside your laptop computer.
lTWOprecise screw-driving potentiometers for professionalaudiophilestoadjust
the tube sbias voltage toguarantee thebest workingpoint fordifferent tubes.
lrequire justasingle +24VpowersupplyONLY,besides the bundled ACadaptor,
audiophilescanapplyallother power supplywiththesame spec.,e.g.lead-acid
batteries.
laspeciallydesignedAC poweradaptorwithextra lowripple &noiseforHi-Fi
deviceisbundledfor continuouspowersupply
lseparate pre-amp unit &poweradaptortominimize interferenceandflexibleto
applyotherpower sources,e.g. lead-acidbattery.
lallaudiophile-graded partsand components
lthestylishaluminiumcaseprovidesoutstandingshielding&groundingcapability to
keeps the backgroundsilentand maximize theS/Nratio.
TrendsPA-10 User Guide
Section 4.Overview 6
4
4. . O Ov ve er rv vi ie ew w
Front View
1. Headphone Socket
2. Volume Controller –TurnAnti-clockwiseto minimizethe volumelevel and vice
versa.
Back View
3. PC/iPod –Input from PC/Mac/iPodwithhigher gain usingaudiocable
(2RCA-2RCA)
4. CD/DAC- Input from CD/DAC usingaudiocable (2RCA-2RCA)
5. Input –Selection for CD/DACor PC/iPodinput. Thedefault is CD/DAC input
6. Output –Toanyline levelinput on youramplifierusingaudio cable(2RCA-2RCA)
7. PowerON/OFF switch –pull upto poweron thePA-10andpulldowntopower
off.
8. PowerSupplySocket –Plug thebundledACAdaptortothis socketto supply
power.

TrendsPA-10 User Guide
Section 5.Hints &Tips/Section 6. Specification 7
5
5. . H Hi in nt ts s & & T Ti ip ps s
lTry to have a soft workarea incaseyou dropthetube.
lUsecloth gloveor baggietohold the tubes, wipeoff any fingerprintsonglass
portion oftube with asoft cloth.Fingerprints canlead toprematuretube failure
lTry not putexcess forceontheglassofthe tube thiscan(rarely) causetheseal
betweenthe glass and base toleakthe vacuum.
ldo not leave TrendsPA-10unattendedforlonglengthsof time duringthe 22
hourinitialburn-in
lThesound ofTrendsPA-10 willopenupafter about5minutes ofwarm-up.At
least half anhourof warm-up, if youaredoing someaudiophilelistening
lAlways waitat least5minutespriortoturningTrends PA-10 backonafter
turning it off.
6
6. . S Sp pe ec ci if fi ic ca at ti io on n
6.1 Specification ofthe Pre AmplifierUnit
VacuumTube 6DJ8/6922series or12AU7series (exchangeable)
OutputStage MOSFETx2
Amplification Gain x3(forAudioCD/DACIN)
x6(forAudioPC/iPodIN)
Signal-to-Noise Ratio(SNR) 92dB
DynamicRange 92dB
THD+Noise 0.05%@10k ohm
0.15%@33 ohm
Input AudioCD/DACIN RCA(Left/Right)x1[3Vpp max.]
AudioPC/iPodINRCA(Left/Right) x1[0.55Vpp max.]
PowerSocket (5.5mm/2.1mm) x1
Output AudioOUT RCA(Left/Right)x1
Headphone OUT(3.5mm) x1
OtherSwitch&Knob AudioINselectionswitch x1
PowerON/OFFswitchx1
PowerIndicator (BlueLED underTubeSocket)x1
Volume Knob x1
Power Supply DC 24V-26.5V(max.)
Dimensions (W)76mmx(H)46mmx(D)114mm
Weight 380g
TrendsPA-10 User Guide
Section 5.Hints &Tips/Section 6. Specification 8
6.2 Specification ofthe Headphone Amplifier Unit
VacuumTube 6DJ8/6922series or12AU7series (exchangeable)
OutputStage MOSFETx2
Amplification Gain x3(forAudioCD/DACIN)
x6(forAudioPC/iPodIN)
Signal-to-Noise Ratio(SNR) 92dB
Power Output: 3.0Wattsperchannelon 33Ohm Headphone
Frequencyresponse: 15Hz-100kHz-1db
InputImpedance: 100k Ohms
THD+Noise 0.05%@10k ohm
0.15%@33 ohm
Input AudioCD/DACIN RCA(Left/Right)x1[3Vpp max.]
AudioPC/iPodINRCA(Left/Right) x1[0.55Vpp max.]
PowerSocket (5.5mm/2.1mm) x1
Output AudioOUT RCA(Left/Right)x1
Headphone OUT(3.5mm) x1
OtherSwitch&Knob AudioINselectionswitch x1
PowerON/OFFswitchx1
PowerIndicator (BlueLED underTube Socket)x1
Volume Knob x1
Power Supply DC 24V-26.5V(max.)
Dimensions (W)76mmx(H)46mmx(D)114mm
Weight 380g
6.3 Specification ofthe AC Adaptor
ACInput UniversalAC100V-240V/50-60Hz
DCOutput DC 24V0.6A(15W)
DCPlug DC 2.1mm
Ripple&Noise <=25mV
Over-load Protection 105%-150%
Over-voltageProtection 115%-150%
Dimensions (L)78mm x(W)50mm x(H)33mm
Weight 150g
lTwo-Year limitedwarranty forTrends PA-10
lOne-Year limitedwarranty forthetube
lTocontinuously improveourproduct,wereservetherightstochangesome
specifications withoutfurther notice.

TrendsPA-10 User Guide
Section 7.Comparison/Section 8.Technical Notes 9
7
7. . T Tr ro ou ub bl le es sh ho oo ot ti in ng g
Ifyour machineisoutoforder,itmay notbevery serious.Before you callyourlocal
distributororus to repair,you are suggested tocheck the following:
Symptoms PossibleReasons HandlingMethods
powercordsnot properly
connected
properlyconnectthe power
cords
cannot power ON
indicator notbright
powerswitchisOFF switchON thepower
thevolumelevelistoo low turnvolume levelhigher
theaudiocablenot properly
connected
properlyconnectthe audio
cable
theaudiosource (e.g.CD
player) not started playing
start playing theaudiosource
wrong input isselected check inputselection
no sound atall
thespeakercables not
properlyconnected
properlyconnectthe speaker
cables
hum tube notfullypushedin insertTube securely
audioconnectorplug notfully
pushed in
insertplug securely
incorrect inputswitchposition
check thecorrespondinginput
switch
sound out(s)out loose connection check inputandoutput
connections.Whenall has
been double-checked reduce
volume andswitch unitback
on
8
8. . A Ac cc ce es ss so or ri ie es s
•Tube x1
•+24V powersupplyx1
•User Guide x1
•WarrantyCard x1
TrendsPA-10 User Guide
Section 9.Troubleshooting /Section10.Accessories 10
9
9. . C Co om mp pa ar ri is so on n
Model TrendsPA-10 Trends PA-10 SE*
TrendsPA-10 GE*
Tube Chinese 6N11 Russian 6H23n U.S.AGE 12AU7
Tube Types 6DJ8/6922series 6DJ8/6922series 12AU7series
Audiooutput Capacitor
10uF cap(Black) EVOXcap(White) EVOXcap(White)
Sound Quality Balance soundinfull
rangeand goodfidelity
Relative thicker &
heavier bassand good
onorchestral
Relative warmer mid
range and excellent
femalevocals
lTrends PA-10SE: Trends PA-10TubeHeadphone/PreAmplifier -Special Edition
lTrends PA-10GE:TrendsPA-10 Tube Headphone/PreAmplifier-GE Edition with
12AU7Tube series
1
10 0. . T Te ec ch hn ni ic ca al l N No ot te es s ( (f fo or r p pr ro of fe es ss si io on na al l u us se er r o on nl ly y) )
Trends Audio hasalready pre-set thejumpers andfine-tuned the DCbias voltageof
eachPA-10 withthe packagedvacuumtubebeforeshipping. However,changing
differenttubes totastefor differentsoundisthegreatfunformany audiophiles and
alsoagreat feature ofPA-10.There are some importantnotes shouldbe awarebefore
changing tubes.
TrendsPA-10supportstwomajortubeseries: (1)6DJ8, 6922, 6N11,6H23n,ECC88,
E88CC, etc ,and (2)12AU7, 5963,5814, ECC82,etc Ifyou changethe tube
withinthe same series,it needs to re-tune the DCbias voltagesONLY.Ifyou change
thetube from anotherseries, it needsbothtore-tune theDC biasvoltages andre-set
thejumpers. Otherwise,the tube maybe burnt out.
10.1 Jumper Setting forDifferent Tube Series
You cansimplyconfiguretheamplifiertosupport the twodifferent tubeseries by
resettingthejumpers inJ3,J4,J5inthePCBasfollows.(RemembertopowerOFF
themachinebefore setting)
6DJ8 series 12AU7series
J3
O O O
O O O
OO O
OO O
J4
O O O OO O
J5
O O O OO O

TrendsPA-10 User Guide
Section 9.Troubleshooting /Section10.Accessories 11
10.2 DC Bias Voltage Tuning
Since each tubemay derivate abit in parameters, especiallyfrom different series,it
needstore-tunetheDC biasvoltagestoguaranteethemachineis workinginthebest
point andperformingthebest sound quality.
Therearetwoblue preciseadjustable potentiometers (R3,R13) fortuningtheDCbias
voltage ofeachchannel.TheDCbias hasbeentuned infactory.Butafterrun-in for a
period orchanged another tube, it would be deviatedthat the fine-tuning isneeded.
Beforeyoutune these,youneedascrewdriver (take offthe case),asmallscrewdriver
(turn the screwofthepotentiometer)anda (digital)multi-meter to detecttheDCbias
voltage.
1. Use screwdriver totakeout thetwoupper levelscrewsinthefront panel&
another twoscrewsinthe back panel.Then,opentheuppercase.
2. PowerONthe machine with no audio signalinput.
3. Waitatleast5minutes for the machine torun in.
4. Use the multi-metertodetectthe DCvoltagebetweenthe testpoint A(L) [red]in
thePCB&the GND [black] (e.g. the ringofthe power switch or theouterringof
thoseRCAsockets) ofthe LEFTchannel.
5. Turnthe screwonthetopof the R3 potentiometer byasmall screwdriver
clockwise oranticlockwiseuntil thevoltage as closeasto +16.5V.
6. Then, repeatstep4and 5for the RIGHTchannel by changingthe testpointto
A(R) [red] andturning the screw on the top of the R13 potentiometer.
7. PowerOFFthe amplifier.
8. Cover backthe upper caseandtightenthe screws.
TrendsPA-10 User Guide
Section 11.RegulatoryCompliance/Section12. Contact Us 12
1
11 1. . R Re eg gu ul la at to or ry y C Co om mp pl li ia an nc ce e
This device complieswithPart15oftheFCCRules. Operationissubjecttothe
followingtwoconditions:
(1) this devicemaynot cause harmfulinterference,and
(2) thisdevicemustaccept anyinterference received, including interferencethatmay
causeundesired operation.
Warning: Changes ormodifications to thisunit not expressly approvedby theparty
responsibleforcompliance could voidtheuser's authorityto operatetheequipment.
NOTE:This equipment has beentestedand foundtocomplywith the limitsforaClassB
digitaldevice,pursuant toPart15of theFCCRules. Theselimitsare designed toprovide
reasonable protection againstharmfulinterferenceinaresidentialinstallation.This
equipmentgenerates,uses andcanradiateradio frequency energyand, ifnotinstalled
and used in accordance withthe instructions, maycause harmfulinterference toradio
communications.
However,thereisnoguaranteethatinterferencewill notoccur inaparticular installation.
Ifthis equipment doescauseharmfulinterference toradioor televisionreception,which
canbe determinedbyturning the equipmentoffandon,the userisencouraged totry to
correctthe interference byone or moreofthe followingmeasures:
- Reorientor relocate thereceiving antenna.
- Increasetheseparation betweentheequipmentand receiver.
- Connect theequipment into anoutletonacircuitdifferent fromthattowhichthe
receiver is connected.
- Consultthedealer or anexperienced radio/TV technicianfor help.
1
12 2. . C Co on nt ta ac ct t U Us s
ITOKMediaLimited (Trends Audio)
Address: Unit E, 13/F., World TechCentre,
95HowMingStreet, KwunTong,Kowloon, HongKong
Phone: [phone](9am-6pm, HKGTime)
Fax: [phone]
Email: [e-mail] (Sales)
[e-mail] (Support)
Web:http://www.TrendsAudio.com