or those in the marketfor a top quality DAC,Audiolabl M-DAC hasbeen the go-to productfor many years. Unlovely inappearance, it was lovely in

sound quality - and affordable.Thenew M-DAC+ is even less lovely inappearance, but it addresses weakpoints in the original M-DAC, to giveeven better sound. And it remainsaffordable, carryinS a price lag of justf850.

Otherwise much remains thesame, since you don't want to chanSea successful formula for the sake of it

and in any case there wasn't muchleewat to change aq.thingi Arrdiolabgot it mostly ritht in the first place.

The original M-DAC scoredby using the best DAC (Digital-to-AnaloSue Convertor) chip available atthe time. the ESS ES90l8 from theirSabre32 series, put into a box with a

set of unique digital filters - no lessthan seven of them.

DAC chips are technologicallyvery complex devices, and alsorequire lar8e investment tomanufacture.50 the DAC that liesat the heart of all digital players(e-9. CD players) and external hi-fiDACs like the M-DAC comes froman outside specialist supplier: thinkTexas lnstruments (USA),Wolhon(UK),Asahi Kasei (lapan). Choice islimited and chip manuhcturers seek!o leapfrog each other in order !ocorner the tlobal market.

ln 2008 ESS of Milpitas, California,introduced the Sabre32 seriesDAC chips that have an as@nishintperformance, way beyond all else:people soon took notice. One ofthose people was UK designerJohn Westlake, who isn't aversero complexity, and he based theAudiolab M-DAC around ESS! topquality ES90l8, Sabre32 series DACchip, adding those filters I mentionedin the process.

And that explains how and why

A[diolab's new M-DAC+ hrings bettelquality to CD and hlgh resolutlon digltel,iloel lGwood says.

the first M-DAC was different tomost others.lt was one of the firstto use what proved to be one ofthe best sounding (and measurint)DAC chips on the market at thetime - and ever since, with the sintleexception of Chord Electronicsunique rival DAC, from designer Rob

I hope this tives you some ideaof where top-quality hi-fi DACScome from, how they are designedand what - inevitably - are thelimitations of choice seen by hi-fimanufacturers, lt sets the stage forthe M-DAC+ here, shining light intothe commercial bacllground fromwhence it came.And from where allothers - Chord Electronics excluded

come,These dq/s, rivals using the

ES90l8 chip are popping up all overthe place, includinS price rivals suchas the Northern Fidelity DAC-384 at{650 we reviewed in the January 2016issue - competition is geftin8 fierce.

JUNE 2016 15

The big physical difterencebetween |4-DAC and IY-DAC+ is

that the latter has its power supplybuih in, so comes as a single unit.|1-DAC relied upon an externalswitch-mode power unit connectedby cable terminaEd in a multi-pinDIN slyle plug.The advantage wasno hum - and switch mode powersupplies are more numerous thanducks in China, where this DAC is

made, meaning lhey are cheap.Afterrepeated and fairly heavy use at ourhands thouth, the pins in the powercable plug started to bend and I havehad to apply corrective surgeD/, usinSsnipe-nosed pliers and matnitinStlass. Our usage doesn't mirrorthat of the outside world since weconstanlly pluS and unplug equipment- causing weak connector"s to fail. Butit does suggest where M-DAC had

And then there is the poorreputation of switch-mode suPplieswith regard to sound quality, not tomention the intervention of a cableand connectors between supplyand DAC to degrade sound quality.

Japanese audio companies commonlyplay up the superior sonic results ofconventional linear power supplies

- and along came Oppo with theirBDP- 105D Blu-ray player withES90l8 DAC chip and internal linearsupplies to underline the messaSe: tolinear if you want good sound.

So this is whatAudiolab havenow done. M-DAC+ has a highquality on-board linear power supply,mains power being applied throughthe usual IEC mains plug.

Another new feature of the M-DAC+ is the abilirt to process DSDdigital code, in addition to normalPCM.All modern DAC chips canprocess DSD because it is simpleto do so but enabling this provisionhasn'! been so common becauseDSD files are rare and difficult tolransmit over a USB computerconnection. No point in addingcomplexity and cost when no onewill use it, the thinkint goes.

Yet DSq as originally lsed inSACD (Super Audio Compact Disc),sounds more fluid and natural thanstandard digital (PCM) and has gainedwide respect for this alone.As a

resuh DSD recordinSs have movedour of being an interesting rarilyand into the mainslream - helpedby continued support from Sonywho developed DSD long ago as anarchiving medium. Labels like BlueCoast Records (California) promoteDSD and have a DSD Guide on-line

if you are interested in knowintmore.They are supported directly bySony I found, when visiting them atthe CaliforniaAudio Show, so there!no tack of activity here and thenew M-DAC+ can now handle DSDrecordinSs, up to quad-DSD (DSD2s6).

Thar! new M-DAC+ describedin outline, and what the + monikermeans.Audiolab thankfully haventstripped out any of the originalfeatures that made the unit soflexible- l! still has a high-resolutiondigital volume control that can beswitched ou! if desired, this beingintrinsic ro the 9018 DAC chip.Whatit means is the unit can drive poweramplifiers direct - no preamp needed.The small remote control has volumeUp and Down buftons, as well as

Mute, so volume can be adiustedfrom the selteq the main unit has arotary volume control should Youprefer it (or lose the remote).

The optical S/PDIF diSital inputnow handles l92kHz sample ratePCl4 so it will accept output froman Astell&Kern portable hi-resplayer and not fall silent when a 192file is played, something I suffered

The small remote conttolunit provides all functions,including volume, mute andfifter selection,

continually and found irrilating on theoriginal M-DAC!

There is also an AES/EBUbalanced S/PDIF digital input, thattives slighrly better results thanoptical or electrical inputs - wherean AES/EBU balanced source is

available; they are rare.And then there! a USB B 'uni-

directional' input for connection to a

computer. lt will accept up to 384kHzsample rate PCM, the limit of theES9ol8.You can set a Mac to oulputat this sample rate if you wish, but

BEVIEW

Multiple layers of circuit boards in the newer,high-profile caae of M-DAC+ reveal how complexit has become with on-board power supply andDSD p/ocess,ng,

it won't improve sound qualityi rcsmust have driver software installed.Audiolab include an 8cm miniCDwith necessary software, so you donthave to download it.There! now alsoan iPhone/iPad USB A input.

As before, M-DAC+ has bothunbalanced phono socke! audiooulputs and balanced XLR outputs.Fleasurement showed the XLRS rundirect from the DAC (which hasbalanced output only), tiving the9018's full l25dB dynamic range, butthe unbalanced has been bufferedand has 7dB lower dynamic rangedue to noise in lhe buffer.To set thisinto perspective, at I lTdB it! stillhas the dynamic range of most hithquality DACS but it is a sitnificantshortfall on what is amilable from thebalanced XLR outputs, so obviouslyM-DAC+ is best connected via XLR.

As before, M-DAC+ has a fullsized (l/4 in) headphone output onthe front panel so i! can be used todrive phones from a computer viaUSB.

To play DSD use Foobar 2000for PC Audiolab suggest,AudirvanaPlus for DSD from Mac ({58) orPure Music Player for Mac that worksin coniunction with iTunes,

The seven filters Audiolab havedesigned around the Sabre32 DACchip are impressively effective.Theycan impose quite large changes uponthe sound qlality of CD but theirimpact is less obvious at higher

@

IFal@

oudiolob

JUNE 20,I6 17

REVIEW

sampling rates where the filtercharacteristic effectively moves uP infrequency.

ln essence, three filters are'fast'- Sharp roll off, optimal Spectrumand lYinimum phase.Three are'slow' - opdmal transient, oPtimaltransient XD and OPtimal transientDD.Then lhere's the seventh odd-man-out that is a comPromisebetween fast and slow being calledSlow.

The three fast filters are whatyou get in most di8ital devices, whilstthe three slow filters are mostcertainly not.That\ because they rolloff hith frequencies quite stronSlyand dont offer the best performancefigures, being drastic enough to makeCD sound obviously warm. However,

, Running M-DAC+ on mY

computer desk as a headPhoneamplifler, fed from a Mac via USB, all

worked well. Until, that is, I decidedto load test files from the samecomputer onto mY iPhone via USBcable: iTunes would not see thephone. I had to physically disconnectM-DAC+ before the phone iconaPPeared in i'Iunes.

With test files loaded, the iPhoneplayed via M-DAC+'s USB A input,then all of a sudden it stoPPeddoing so and would not see thephone - even though all else workedproperly and so did the Phone. M-DAC+ needed a re-boot to clear this,meaninS switch-off of mains Powerand removal of IEC Plu8. HaPPily thisdid not happen often.

Xl headphones the overridint qualitywas a sense of massive low endpower, delivered with suPPle ease.

The Darkness 'Growing on Me' (a

CD rip) fairly blew the PhiliPs Fidelioheadphones off my head, the hugerhythmic lead line stretched out wideand solid, underpinned bY enormolsheft.There was a sense of warmth tothe sound that didnt suit the OPPos,that in themselves are a tad laid backup top, so I gravitated to the Xls.The messate here beint that thesmooth, easy sound of this DAC suitsnormal to briSht headphones but less

so those lhat veer the other way.

'Time' from the Pink Floyd(24196) came over as rich andsmooth, with a sense of deeP

seParation between instrumentsacross a wide soundstage - and again

power behind drums and lhe laconicbass line.

Headphone lislening apart,l used1"1-DAC+ fed by a digitally linkedAstell&Kern AKl20 portable playerdriving a Naim NAP 200DR poweramplifier direct, hooked uP to hugeSpendor SP 200 loudspeakers (twol2in bass units no lessl).

These 'speakers have bass

resolution big style and this madeit absolutely clear to me that M-DAC+ has an altogether larger, moremuscular sound than the oriSinal.M-DAC+ is very, very un-CD like -

The rear panel carries phono and balanced XLR analogue audio outputs'At right is an XLR socket for balanced (AES/EBU) digital input, alongsideetectricat and opticat digital SlPDIF inputs. There is also a USB B inputfor computer connection, and USB A for iPhone connection,

months aPart.The little remote was superb I

thought;easy to hold, no sPuriousbuttons and yet able to do it all,including chante fllters.

SOU]ID QUAUTYI started listening to M-DAC+ as aheadphone amplifiei to check its USBbehaviour and iPhone comPatibility.With Oppo PM I and PhiliPs Fidelio

more so than the orisinal model.With The EaSles 'Too Busy

Beint Fabulous' (CD rip) whichusually sounds somewhat messY andharshly bright, 14-DAC+ discardedthe muddle and focussed on theinstruments instead, puttinS definitioninto the bass line, setting the drumsinto their own space whilst clearingthe air around Don Henleyt vocals.A sense of order and clarity were

"a sense of order and claritywere irnposed on the track andit sounded quite different to theway I know it,'they eliminate pre and post ringintin lhe time domain,tiving suPeriortransient performance and, in myexperience, after a while I find I

prefer them, offering an easier andmore relaxed sound,

For those who want this well_damped time domain response butalso some high treble sparkle fromCD there is the Slow filter that is acompromise - and a very good oneunder measurement, if not obviouslyso when listening, but it does dePendupon programme material I find

Filter selection is achieved bY

pushing in the Select knob, rotating itto the filter wanted and pushing again

simple.DSD fllters are included in the

ES90l8 chip and implemented in the1.4-DAC+, so you also 8et three filtershere, but they are simple analotuefilters to reduce the suPersonic noiseone-bit DSD produces and liftleaffect sound quality.

M-DAC may not look lovelY, atleast in the black finish we had, butit is sturdily built. Measuring 247mmwide, I l4mm high and 292mm deeP,

the unit will slot into most sPaces. lt!a neat bit of packagint in fact becauselinear power supplies are bit andthey radiate hum unless yo! use aheavily screened toroidal transformer.Audiolab say there are no fewer thaneight different supply lines and diSitaland analogue are kept separate.

I' e come across obscureApple problems like this before andthey're usually linked to the constantchanges being made byApPle intheir software;heavens l've loadedMavericks,Yosemite and El CaPitan

JUNE2016,: : ':j 1g

REVIEW

imposed on the track and it soundedquile different to the way I know it,being a classic Rock test track usedoften.Just be aware that l'4-DAC+comes over as creamy smooth withrhe sort of warmth associated withanalogue LP rather than anythinSdigital, so it changes what is going on.

With well recorded and balancedRock tracks like Fleetwood l'lac's'GoYour Own Way' (24196) therewas strong dynamic punch to l'1ickFleetwood\ drums. the SP200sdriving our room with gusto. Cymbalsrang with strength here, with the XDfilter giving a well solidified ima8e.

With the Minnesota Orchestraplaying Rimsky KorsakovyDance oftheTumblers' (24196) bowed stingswere lusciously smooth, forming a

caressing backdrop to the solo flute,whilst kettle drum stril<es shook ourlistening room with confident ease.With classical in general, orchestrashad rnassive presence and power;lwas inevitably pummelled by theLSO playing'l4ars' from the Planets(24148), the attressive closinSorchestral sequences having bothforward thrust and sharp timint.

Then I moved to another systementirely for a different view - andspecifically to use the lY-DAC'Sbalanced output, which of{ers a step

up in per{ormance over unbalanced(i.e. phono socket) output.ACreek Evolution l00A amplifierwas switched to straitht-through(i.e. no volume control) from itsbalanced input, and connected torevealinS Quadral Auram l'4egan Vlllloudspeakers.This system soundedextraordinary, even with CD.A senseof immaculate grip and razor sharPtiming became apparent, transientsfrom Terry Evan's steel strinSedguitar coming across with lacerativepower, in GetYour Lies Straitht. Hisgruff trumblinS about his woman,and backSround rumbling pickedup by ihe microphone in this bluespiece all had electric presence.lnfact, I was so taken aback b), thispedormance and all others thatfollowed, I would declare it is thebest lhave ever heard from CD.Thebasic output of the ES90l8 Sabre32DAC is balanced (as it is with mostDAC chips), nor unbalanced - andwhat I was hearing here was the chipat its best in Audiolab's excellentsuPPort environment, now withlinear power supply.I preferred theAudiolab's Optimum lmpulse XDfiltei by the way;with CD its impactis quite noticeable, smoothing thesound and addinS body to mid-rangeinstruments, Extraordinary clarity,

enormous dynamic swings and a

deeply smooth, quiet backgroundgreered me from the balanced outputof the new M-DAC+: it was beyondimpressive, the best I have hearddigital yet.

C0NCl.USl0l'lThe new Audiolab lvl-DAC+ has beenusefully buffed up to keep it ahead ofthe pack. lf you want fablrlous soundquality from CD something theoriginal M-DAC provided in buckets,the new model manages even better.It is deep, open and spacious - butnow has even firmer bass and a

more broad-shouldered sound. Usebalanced output and it gets eversharper timed, forensically clean andclear, with more dynamic contrast,

You also get superb hires ofcolrse and a DAC that has few rivaiswhen hooked up to a computerthrough USB.And all for {850. Pay

much more as in the Resonessencelnvicta Mirus - and you may welltet just a little better. but you'll notget any$int as well designed andeffective under alk by a long margin.The |',1-DAC+ remains the place toto in my view if you're looking fora super high quality DAC.lt's greatpiece of design work and soundswonderful too. even breathtakinS.

MEASUREII PERFltRMANCEThe M'0AC+, at maximum volume on itsdisplay of +3d8, delivered 3.35V fromits phono sockets, and double that at6.7V from its balanced XLR sockets.

Atfull volume it was not in overload.so fullvolume is usable. What +3dBmeans is that output is above Philips Red

Book standard of 2V - that's all.

The higher output of XLR lifts musicfurther above noise and as a result give!improved dynamic range figures. The

best dynamic mnge value from M-DAC+was, surprisingly, from its USB computerconnection that delivered an impressiveI25dB via rhe balanced XLR outputs. Jhisis higher than the original M-DAC by zdBand reache$ Chord's lvlojo. Unfortunately,the uobalanced phono socketed outputdelivered 117d8 dvnamic range - quite a

shortfallon balanced. Although this is aqood result, it iso't exceptional.

All three digital S,PDIF inputsaccepted 192kHz satnple rate siqnal$,includinq optical, but where optical and

elect cal gave 124d8 dynamic range viaXLR out, the balanced AES,/EBU input wasobviolsly quieter the analyset showed,

sivins l25dB.Maximum analogue bandwidth

{68kHz, ldB) was achieved with the0ptimlm Spectrum filter at 192kHz

sample rate.With CD the Slow filter becomes

severe. rolling off treble sharply above

FFEQUEA'CY TESPO'VSE

5kHz, whilst optimum Transient rolls itoll slowly above skHz so both wil' have

quite an obvious audible affect upon CD,

but the other filters are more conventionalin behaviour, optimurn Spectrum giving

flat response to 21kHz for example.ovenll, the seven tilters give a wide

range of diflerinq results: three ofler bestimpulse response with least prelpost

time domain nging, two otfer widestfrequency spectrum and one - Slow

- offers a good compromise.Now with high-quality i0ternal linear

power supply, as well as DSD capability,the M-DAC + continues to offer fineresults all round, the onlY caveat beinqunexceptional dynamic ranqe from thephono socketed, unbalanced oulputs thatmost people use, NK

Frequcrcv response {-1 dB}CD 4Hz-68kHzDistortion (24bit -60dBl "1"0dB.60d8Soparation {tkHz}Noise {lEC A}Dynanic rcnge0utput

AUDIOLAB M.DAC+ f850@@@@@0UTSTANDING - amongstthe best.

VEBDICTA DAC that otfe6 the besrperformance today - andaffordable too. The new lvlDAC+ has it alllor f850: bestsound and the ability to do itall, almost.

FOR- sound quality- flexibilty- flter sel

AGAINST- appearance- dull display- phono dynarnic range

Audiolab UK+44 {0) 1480 447700

DISTORT'ON

0.0020.02

t lzdB.r24d8t25dB

3.4/8.7V

F

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