Introducere:

Dupa o lunga asteptare si nenumarate zvonuri, player-ul portabil FiiO X3 vede lumina soarelui, fiind lansat oficial chiar luna aceasta. Pretul pentru Europa este de 200 Euro. Din fericire am fost unul dintre cei alesi de Fiio sa testeze un model din pre-productie si astfel va pot impartasi parerile mele, rodul a mai bine de trei saptamani de utilizare zilnica.

X3 este primul player portabil al companiei FiiO avand standarde destul de ridicate  si sper sa nu se opreasca aici, deoarece ultimele trei saptamani au fost frumoase, am ascultat muzica pe strada, in travai sau in metrou la o calitate dupa care tanjeam de mult timp.

X3 este aparatul la care FiiO si-a concentrat toate energiile din ultimul an, avand dorinta declarata de a lansa un produs competitiv,  un atac direct la o nisa restransa de branduri audiofile. Concurenta lui X3 nu sunt playerele Apple, Sony, Cowon sau Sandisk, ci mai degraba nume ca iBasso, HifiMan, Astell&Kern (iRiver). Din pacate nu am avut un alt player de acelasi calibru ca brandurile mentionate mai sus, de aceea l-am putut compara doar cu micul Sandisk Sansa Clip+ si cu un iPod Nano.

X3 este simplu de folosit, are meniul foarte usor si intuitiv, nu este complicat, playerul este plug&play, nu are nevoie de drivere sau soft dedicat, muzica se copiaza prin copy/paste, mai simplu de atat nu se poate.

Constructia sa este in totalitate din aluminiu, mai putin plasticul din jurul ecranului, calitatea constructiei este una buna, insa grosimea metalului difera fata de E17 sau E07K, este mai subtire, probabil o reducere de greutate si costuri. Display-ul este maricel, rezolutie decenta, din pacate unghiul de vizibilitate nu este unul foarte bun, display-ul isi face treaba cu brio, nu am avut probleme, insa nu este de calitatea unui iPhone 5, sau a unui Galaxy S3/S4. Daca totusi ne gandim playerul nu a fost gandit pentru vizionare de poze sau nu stiu ce continut multimedia, tinta a fost calitatea audio si nimic mai mult.

X3 are 3 iesiri: o iesire amplificata 3.5mm, o iesire line-out neamplificata (ca sa putem conecta alte amp-uri portabile) si o iesire coaxiala. Da, o iesire coaxiala! Adica poate fi folosit si ca un transport audio pentru un DAC de calitate. Am incercat iesirea de coax si a functionat de minune cu Burson Conductor, astfel pot scoate PC-ul din ecuatie complet.

Playerul are 8 Gb memorie interna si mai poate folosi carduri microSD de pana la 64 Gb, eu am folosit unul de 32 Gb si a mers fara probleme.

La prima privire butoanele de navigare meniu par un pic ciudate, dar dupa 30 min de joaca prin meniu devine simplu de navigat. Mentionez ca playerul nu are absolut nici o functie suplimentara cu exceptia celei de a reda muzica, deci fara radio, inregistrare voce, browser sau alte chestii inutile (pentru mine cel putin), doar muzica si iar muzica.

Playerul reda toate tipurile de fisiere lossless pana la 24 bit 192 Khz!!

Adica stie FLAC, APE, ALAC, WAV cat si restul formatelor lossy MP3, OGG si WMA. In prezent sunt multe DAC-uri daca nu suporta fisiere 24 bit, dar micutul player le reda pe toate.

Playerul foloseste practic aceleasi componente interne ca si in cazul DAC/Amp-ului E17 (DAC Wolfson 8740 si op-amp de amplificare AD8397) si pot spune ca ambele suna foarte apropiat.

Performanta audio:

Ca si sunet playerul suna foarte apropiat cu E17 si semnificativ mai bine decat playerele cu care l-am comparat.

Punctul forte al playerului fata de concurenta a fost redarea scenei, nivelul de detaliu si lichiditatea sunetului. Din cele 3 cu care l-am comparat, iPod-ul a sunat cel mai digital si uscat, Sansa Clip+ a avut sunetul mai in fata si un pic incetosat, X3 in schimb a fost cel care a sunat bine din toate punctele de vedere.

De exemplu pe folk-ul balcanic Gothart, folosind X3 cuplat la o pereche de Sennheiser Amperior, mergand pe strada, am avut impresia ca stau si-mi ascult sistemul de acasa. Aglomeratia muzicii pe care o poseda toate playerele portabile a disparut, sunetul a devenit mai aerisit, scena a devenit mai mare, fiecare instrument pluteste intr-un spatiu vid propriu. Totul pare mult mai realist si natural. Pentru comparatii am folosit un switcher simplu prin care comutam toate cele 3 playere dintr-un singur click. De aceea compararea celor 3 playere a fost floare la ureche. Stand asa cu ochii inchisi in momentul in care comutam pe X3 sunetul devenea mai amplu si parca un pic mai distant, de parca muzica ar veni undeva de afara si nu din casti, un efect placut si interesant. De asemenea am observant ca macrodetaliile nu dispar deloc pe Fiio X3, aud nuantele ascunse, chiar si majoritatea microdetaliilor care le aud numai acasa. Playerul de asemenea are un caracter mai natural, mai moale si mai cald. Nu are un sunet super netru sau liniar, este un pic mai muzical si mai placut urechii fata de restul playerelor. X3 sta bine si la capitolul dinamica, datorita amplificatorului potent care il detine, playerul suna rapid, controlat si tine pasul cu muzica. Muzica clasica suna lent si dulce, iar muzica mainstream suna dinamic, rapid si cu mult nerv.

Playerul are doua setari de gain (low si high) si de asemenea doua setari de EQ (bas si inalte). Pe Sennheiser Amperior a fost suficient jumatatea volumului pe low gain, am incercat playerul chiar si pe Sennheiser HD800 cat si pe Audeze LCD-3. Pe high gain si cu volumul la 80% a sunat decent ca volum, insa s-a pierdut multicel din dinamica. Pe casti grele recomand un amplificator portabil adaugat pe iesirea de line-out (un E12 de exemplu), pe casti de impedanta joasa spre medie playerul nu are problem de amplificare, avand cam aceeasi iesire de putere ca si in cazul E17.

Mi-a placut redarea basului si mediilor pe acest player. Basul a sunat autoritar si bine definit. M-am delectat cu niste The Prodigy, Chemical Brothers si Infected Mushroom pe care X3 a sunat rapid, avand o buna lovitura si un ritm rapid. Zambetul de pe fata si topaitul piciorului drept au fost primele semne ca playerul stie sa faca din sunet – muzica si sa-mi creeze o stare de bunadispozitie.

EQ-ul este bine implementat, am testat ajustarea basului si a inaltelor si nu modifica si restul frecventlor audio cum o fac alte playere. Pentru un bas mai cutremurator +5 dB este suficient, chiar si pentru maniacii de bas, setarea de inalte face acelasi lucru. Eu am preferat insa setarile stoc, totul pe zero. Dupa cum spuneam si mai sus, chiar neatingand nici o setare playerul nu suna foarte liniar sau super tehnic, este mai mult gandit spre un caracter analogic. Este lipsit de sibilanta sau de inalte taioase, iar frecventele medii nu sunt deloc uscate sau fara substanta ca si in cazul iPod-ului.

Am apreciat si imaginea stereo centrata si delimitarea usoara a fiecarui instrument audio din piesele preferate. Muzica aglomerata nu mai suna ca un terci de ovaz fara gust si culoare, dar mai mult ca o salata de fructe, colorata, dulce si plina de gust.

Am folosit si cateva fisiere hi-rez de 96 cat si 192 kHz. Sunt redate fara distorsiuni, fluid, fara poticneli. Nu sunt adeptul muzicii hi-rez, sunt prea putine albumele bune si de aceea nu am testat prea cu fisiere mari. Este bine de stiut insa ca daca aveti albume in 24 bit, se poate asculta fara probleme si pe X3 fara a fi nevoie vreo conversie catre 16 bit.

Am remarcat lipsa hiss-ului pe casti de impedanta foarte joasa. Folosind cascutele custom US 3D pe low gain, la volumul maxim la care am putut rezista nu am auzit hiss sau zgomot de fundal, playerul demonstrand ca are un fundal negru si este lipsit de distorsiuni.

Iesirea coaxiala este interesanta si daca vreti sa scoateti PC-ul din lantul audio pentru a alimenta DAC-ul din dotare cu fisiere lossless Fiio X3 poate face acelasi lucru, desigur nu suna ca un transport scump de inalta calitate sau ca o interfata S/PDIF bine pusa la punct insa isi face treaba si nu suna deloc rau. Ca sa va faceti o idee am testat X3 vs Logitech Squeezebox pe iesirile spdif si a fost meci egal.

Ca un tot intreg cred ca playerul are un caracter fun, vioi, rapid si dinamic. Nu suna deloc lenes sau dat pe spate (laid back) , blurat sau nefocusat.

Performanta sa este comparabila cu cea a multor DAC-uri din zona entry level spre zona de mijloc si sunt sigur ca suna mai bine decat majoritatea placilor audio interne dedicate pentru calculatorul personal si totul intr-o cutie de dimensiunile unui telefon mobil.

Ar fi interesanta si o comparatie cu playerele mai scumpe ale concurentilor aprigi din acest segment de playere portabile, poate la urmatoare recenzie, cu o alta ocazie.

Concluzii:

Placerea de a asculta muzica pe strada in fiecare zi pana la servici si inapoi m-a facut sa apreciez enorm micutul player. Mi-a intrecut asteptarile in ceea ce priveste performanta audio, calitatile sale amintind de perfomanta unor scule de casa. Calitatea constructiei nu este de nivelul unui iPod si nici display-ul nu este unul de top, dar daca trecem peste aceste neajunsuri avem un produs care satisfice nevoile audiofilulu roman cu buzunarele mai putin adanci. Pretul mi se pare unul corect, ba chiar ieftinut pentru ceea ce ofera si ce poate.

Primeste recomandarea mea pentru cine doreste o calitate superioara a redarii muzicii pe strada comparativ cu restul playerelor comercializate in Romania.

Pro:

– Suportul deplin al tuturor fisierelor lossless pana la 24 bit
– Suportul cardurilor microSD pana la max 64 Gb – more music, more fun!
– Are 3 iesiri! (doua analog, una digitala)
– Scena larga, imagine stereo precisa
– Macro si microdetalii definite, sunet aerisit
– Naturalete, dinamica ridicata, caracter vioi
– Pretul bun pentru performanta oferita

Contra:

– Finisajul nu este chiar milimetric, display-ul slabut
– Nu este liniar sau neutru ca sunet

Experimentul lui Savu:

Am avut o mare curiozitate. Ce poate face X3 cuplat la un amplificator E12 asa ca am decis sa pun cele doua aparate impreuna si sa folosesc niste Audeze LCD2. Pentru senzatii tari am plecat pur si simplu pe strada, cu uriasele Audeze pe cap. Pentru putina sare si piper am dat o raita printr-o statie de autobuz unde lumea se uita la mine discret, da vadit interesata.

 Sunetul a fost surprinzator de bun, nu-mi imaginam ca doua jucarii portabile pot pilota niste casti atat de dificile. Am obtinut cel mai bun rezultat pe low-gain (la E12), volumul a fost o idee sub ce mi-as fi dorit, mai ales ca eram pe strada cu mult zgomot ambiental, dar a fost foarte bine. Pe high-gain volumul este mai mult decat pot eu suporta dar apare un anumit zgomot de fond, este clar ca undeva trebuia sa existe o limitare.

Concluzia finala: Audeze trebuie sa scoata musai si niste casti de strada!

Sennheiser anunta anul trecut  primele sale amplificatoare de casti dedicate HDVA600 si HDVD800, identice pe partea de amplificare dar diferite prin convertorul D/A integrat in modelul mai scump.

Ei..nu sunt chiar primele amplificatoare Sennheiser daca luam in calcul si HEV90 lansat in anii ’90 sau mai tarziu in anii 2000 modelul HEV60, ambele dedicate electrostaticelor HE90 si respectiv HE60 dar acestea sunt mai mult legende decat lucruri palpabile. Ambele modele au fost ultra rare si foarte putini sunt cei care le-au ascultat macar o data.

Avand in vedere ca Sennheiser inca nu a produs nici un amplificator pentru castile sale dinamice, anuntul de anul trecut cu privire la iminenta lor lansare a pus capat unei lungi perioade de asteptari din partea fanilor.

Eu cred ca este o decizie destul de intarziata, avand in vedere ca HD800 au fost lansate in 2009 si fiecare posesor de HD800 detine deja cel putin un DAC si un amplificator decent. Oare va putea noul HDVD800 interesa posesorii de HD800 si sa se reorienteze la aceasta solutie all-in-one  fata de aparatura care deja o detin? Nu stiu..insa insir impresiile mele dupa o ascultare minutioasa de aproape 3 saptamani, timp in care am intors HDVD800 pe toate partile.

Expresia de “German Engeneering” des intalnita la multe produse Made in Germany nu este folosita aleatoriu. Chiar de la prima privire si atingere iti poti da seama ce au vrut sa transmita teutonii prin aceasta expresie. Gadgetul audiofil este construit cu o precizie uluitoare, milimetrica chiar. Desi greutatea si volumul nu impresioneaza, sare in ochi finisajul frumos, si atentia la detalii, arata chiar un pic futurist, un design ce se combina frumos cu HD800.

Aparatul este relativ usor (~2kg) insa specificatiile impresioneaza:  balansat 100% cap coada, intrari analogice RCA cat si XLR balansate, intrari digitale USB, coaxial, optic si AES/EBU, iesire de DAC XRL si iesiri de casti 6.5mm cat si XLR balansate, DAC chip TI Burr-Brown 1792. Potentiometrul este de calitate superioara, 10KDX4 de la Alps.

Personal imi place lumina albastra a butonului de power si geamul deasupra prin care se vad o parte din circuitele interne si rotita de volum foarte lina si placuta la atingere.

Amplificatorul din pacate nu are un comutator de gain pentru casti de diferite impedante si sensibilitati.

HDVD800 l-am folosit obligatoriu impreuna cu HD800, dar am incercat din curiozitate si LCD-3 pe el, la ambele am avut disponibil si cablu balansat.

Aparatul a fost supus unui burn-in de peste 100 de ore inainte de a fi testat cu cea mai mare atentie.

Muzica devorata a fost:

Alternosfera – Epizodia

Django Reinhardt – The Best of Django Reinhardt

Gothart – Cabaret

Hans Zimmer – Man of Steel OST

Led Zeppelin – Mothership

Eluveitie – The Arcane Dominion

Vita de Vie – Acustic

Sha’s Banryu – Volume One

Probabil ca deja va ganditi de ce pentru niste casti asa ca HD800 am folosit asa mult rock, folk si muzica jazz. Acest model este cunoscut ca fiind mai putin potent pe aceste genuri muzicale, mai ales pe rock. Ei, am ales aceasta muzica pentru ca HDVD800 transforma aceste casti radical, fiind o combinatie cu totul speciala.

Performanta audio:

Chiar de la prima auditie, mi-am dat seama usor ca DAC/Amp-ul a fost gandit si dezvoltat folosind HD800, nu este nici un dubiu in acest sens.

Nu pot vorbi despre topologia amplificatorului sau ce fel de cirucuite, respectiv componente au fost folosite, insa un lucru e sigur, cu el HD800 isi ia zborul…

Detinand HD800 mai mult de 3 ani, le stiu bine caracterul, punctele lor forte  si slabiciunile. Dupa vechile mele recenzii se observa ca m-am reorientat mai mult catre planar magneticele LCD-2 si apoi catre LCD-3 datorita sunetului mai pentru sufletul meu. Mereu am simtit ca HD800 le lipseste tonalitatea corecta a unui instrument din lemn, greutatea unui contrabass sau emotiile care ti le lasa piesele preferate. Inaltele de multe ori pentru mine erau abrazive si zgaraiecioase si astfel cu timpul le-am folosit din ce in ce mai rar.

Folosind HDVD800 imi vine sa sterg ultimele 2 fraze scrise despre aceste casti si sa inversez totul.

Este destul de uimitor cum au tunat Sennheiser acest aparat si cat de serios s-au gandit sa modifice HD800 in ceea ce probabil au vrut sa faca de la inceput, fara sa le iasa asa cum si-au dorit.

Destul de remarcabil este basul la HDVD800. Basul este autoritar, bine definit, precis, se aud cele mai joase octave fara a ma zgribuli la fata ca sa le aud. Da, este adevarat, aparatul nu este unul neutru sau liniar dar nici nu se vrea a fi unul. Basul a fost intentionat ajustat pentru ultimele 2 modele de top lansate: HD800 si HD700. Daca pe alte amplificatorare (exceptie Soloist si Conductor) basul a fost anemic, rusinos si pe planul doi, pe HDVD800 el este bine definit si destul de greoi si agresiv. Am ascultat rock pe HD800 de parca eram la un mini concert.

Fecventele medii am simtit ca nu prea au fost atinse, dar nici nu prea era nevoie. Se stie deja ca HD800 pot reda voci cat si instrumente pe corzi, pian si alte instrumente in zona medie a spectrului de frecvente cu o precizie foarte buna. Am simtit usor de tot o rotunjire, a fost adaugat un gram de muzicalitate, un strop de dulceaza in cana cu apa pura.

Folk-ul balcan Gothart a sunat sublim! Am reascultat albumul de mai multe ori si de fiecare data am ramas socat de lejeritatea sunetelor care curg si de limpezimea lor iar focusarea a fost foarte usoara catre orice instrument.

Mi-a placut la fel de mult si albumul Acustic al celor de la Vita de Vie, a sunat  emotionant, plin de metafore si de sensuri ascunse, viu si natural, nici o urma de sibilanta sau de dinamica cheala. Prestia a fost una energica si naturala, iar HD800 si-au aratat adevaratul potential.

Pe frecventele inalte a fost usor simtita o schimbare de atitudine, o taiere al inaltelor de sus (de la 15 khz in sus) – cred ca fost facuta intentionat pentru a recapata mai mult fani in randul posesorilor de HD800. Inatele au fost redate foarte usor la ureche, neagresiv, de parca iti gadila urechea in loc sa o sfasie. O combinatie aproape perfecta pentru HD800.

Remarc ca am ascultat HD800 conectate in mod XLR si impresiile de mai sus sunt toate formate in contextul conexiunii balansate.

Pe iesirea de 6.5mm s-a observant ca scena s-a micsorat considerabil, instrumentele au devenit mai aglomerate, iar dinamica a avut de suferit.

Are logica, pe iesirea balansata de casti, HDVD800 pompeaza de doua ori mai mult current si voltaj iar in acelasi timp ofera si o distorsiune armonica mai joasa. De aceea daca deja va ganditi la HDVD800 atunci va sugerez si un cablu balansat, combo-ul HDVD800 + HD800 doar asa ar trebui ascultat.

Bine..toate bune si frumoase cu HD800, dar din curiozitate am incercat si LCD-3 pe aceasta minunatie de amplificator si…surpriza!

Dinamica a disparut, viteza a disparut, totul a devenit nefocusat, iar basul a devenit lent si de tip “butoi gol de bere” 🙂

Ce s-a intamplat, cui se datoreaza acest lucru, am stricat LCD-3?

Nu am stricat nimic, dupa o cercetare mai minutioasa se pare ca inginerii Sennheiser au decis ca iesirea de casti sa aiba o impedanta de 47 de Ohmi…Fapt care si imi explica acum de ce este o idee proasta spre foarte proasta in a folosi HDVD800 pentru casti de impedanta joasa spre medie.

O idee proasta din punctual meu de vedere, toata bucuria care am avut-o cu HD800 a fost complet distrusa pe Audeze. De aceea nu consider HDVD800 un DAC/Amp universal cum ar fi Burson Conductor sau cum mai sunt si altele care folosesc zero ohmi la iesirea de casti. Nici macar cascutele mici de tip IEM sau CIEM sunt o combinatie proasta folosind HDVD800, adica adio Sennheiser IE80 si IE800 pe acest aparat.

Am avut ocazia sa compar amplificatorul cat si DAC-ul intern cu cel al lui Burson Conductor.

Performanta DAC-ului din HDVD800 a fost inferioara aparatului australian. Pe HDVD au lipsit unele microdetalii (cea mai mare diferenta) si sunetul a fost putin mai aglomerat si mai nefocusat. De asemenea a avut de suferit si rafinamentul ultimativ cat si liniaritatea mai reala pe Burson.

Amplificarea in schimb a fost ca un cameleon, pe HD800 suna sublim, insa pe alte braduri de casti poate suna complet opus si fara nici o sinergie. Conductor suna la fel pe toate castile, de orice impedanta si pe orice producator de casti.

Daca HD800 sunt unicele casti care va intereseaza sau care le doriti, atunci cred ca HDVD800 ar fi printre cea mai buna alegere. Dupa mine HDVD800 este in primul rand un amplificator de casti si apoi un DAC. DAC-ul intern nu se ridica la nivelul performantei amplificatorului. Mentionez ca daca deja detineti un DAC care va place cum suna, atunci mai bine salvati niste bani si optati pentru HDV600 (un HDVD800 fara DAC) care este identic in ceea ce priveste amplificarea. Nu prea recomand si nu vad rostul folosirii HDVD800 ca DAC pentru alte sisteme audio din casa, performanta DAC-ului este buna, dar nu stralucitoare.

In incheiere:

Un aparat foarte interesant si o adevarata mana cereasca pentru posesorii de HD800 sau de restul gamei Sennheiser de top (HD700, HD650) si mai putin interesant pentru alte casti de top. Nu exclud posibilitatea ca modelele cu impedanta mare de la Bayedynamic (T1 sau DT880) sa fie foarte potrivite cu HDVD 800, din pacate acestea nu au fost disponibile in momentul testului.

Calitatea constructiei este una foarte buna, chiar nimic de reprosat la acest capitol. Aparatul este bine finisat si facut cu mare grija. Design-ul futurist este in rand cu moda (aka HD800).

Prestatia sonora impreuna cu HD800 este la cel mai inalt nivel si un combo de invidiat avand in vedere sinergia intre cele doua. Cautati un combo DAC/Amplif care se impaca de minune cu HD800? Daca da, atunci HDVD800 primeste recomandarea mea maxima.

Pro:

– Calitatea constructiei impecabila, design futurist
– Conectica foarte buna
– Dinamica ridicata, transienti rapizi
– Sunet detaliat, foarte usor la ureche, neabraziv
– Tunat in special pentru HD800, o sinergie perfecta
– Convenienta de a conecta simultan 4 perechi de casti, amplificator balansat potent

Contra:

– DAC-ul nu se ridica la performanta amplificatorului
– Sinergie slaba impreuna cu alte casti de impedanta mica, nu este universal
– Costul cam piperat

Echipamente folosite pentru recenzie:

Sennheiser HDVD800, HD800, Amperior, Audeze LCD-3, Burson Conductor, cabluri Audioquest.

INTRO:

Most of computer motherboards to date come with standard audio ports & although the output leaves much to desire, it appears they suffice for most users. There are also different kind of people, owners of quality audio systems, people for whom music means more than some bare sounds without flavor. Dedicated to these people, Asus created Xonar range, which dominates with authority this market segment. Essence ST/STX model is the current pinnacle of soundcards for computers, a product which left Asus competition’ without reply until to date. All the praise goes to this achievement, but since nothing in this world is perfect, this soundcard has also its limitations, being foremost exclusively designed for desktop users. The notebooks’ market has become dominant these years & its users had no other option than to go to Essence One model, much powerful, but twice as much as expensive.

To cover this void in their lineup, Asus has focused its efforts & they had launched Xonar Essence STU, which at a price of approximately 250€ is at half distance, price wise, between Essence One and Essence ST/STX models.

 PRESENTATION:

As you can see, we have a soundcard with asynchronous USB, a little sister of the world renowned Xonar Essence One. At a quick view of its internal components, one can notice easily that we’re talking about an external version of the exquisite Essence STX, to which we can add the advantages of an external solution regarding the dedicated power supply & the avoidance of the electromagnetic fields generated by various PC components inside a case. Let’s have a look at what is exactly under the metallic hood:

– DAC BurrBrown PCM1792, present in both STU & STX variants, is a performance chip from Texas Instruments & it can be seen in top audio devices, like CD-player Primare CD22 which has a retail price above 1.200€.

– headphone amplifier 6120A2, same one used with STX or Xonar Xense.

– OPAMP: 2x JR06ABE3 LME  & 1x JR12ACE3 LM 4562NA from National Semiconductors. These are operational circuits which can also be found in top of the line product Essence One. They are socketed & as such, they can be replaced at users’ whim.

– asynchronous USB is based on chip CM6631A from C-Media, same solution being used in case of its elder sister, Essence One. This chip is able of up sampling rates until 24bit/192KHz.

– audiophile grade Nichicon Fine Gold & Wima FKP2 condensers. These condensers are to be found in many expensive audio products, being specially designed for this kind of electronic products.

On the front panel we can found the jack for headphones, in size of 6.3mm, two volume potentiometers, one for the headphone output & the other one for RCA out. The consumer side of this product can be seen in the potentiometers used, entry model A100k coming from Taiwanese company Alpha. On this chapter we can see the two buttons, for on / off & for choosing the desired digital entry being used. In the rear we can see the digital input for toslink, usb & coaxial & RCA analogic outputs. Here we can find the switch in two steps to control gain for headphones output.

RCA outputs can be fixed or variable by using a jumper on the motherboard, its default position being that of a preamplifier already active. There is a global trend lately so that the function of preamplifier to be integrated in the digital to analog converters. I’ve tested many types of equipment with this solution & the results were not convincing, especially when we talk about entry level hardware.

TESTING METHODOLOGY:

For the headphone output I have used two Sennheiser headsets, one being more accessible than the other – HD558 versus the exclusive HD700. Using the latter I tried to test the integrated headphone amplifier.

For the stereo music I have used my new amplifier Simaudio Moon 340i DPX, together with the academic bookshelves Dynaudio Focus 160. Although this system can appear quite expensive relating to the sound card Xonar Essence STU, I’ve chosen this system because I know it very well. With this configuration I can sense very easy any change & thus it’s easier for me to notice the differences.

I have used the latest iteration of Foobar2000 together with Asio, the plugin being included in the driver of Xonar Essence STU. This is the reason why the “bit-perfect” led lightens on the frontal panel during its use.

SOUND:

As I expected, the sound exercise of Xonar Essence STU is close to that of our older           acquaintance, Xonar STX. Having small variations in one direction or the other, models Xonar STX, D2, Xense, Phoebus or STU give approximately same sound quality & I think that it doesn’t pay to change one version for another, expect in particular situations.

Compared to the sound cards aforementioned, Essence STU comes with a little advantage in the scene presentation chapter, this one being much more extended & enveloping. Because I was in the mood for hearing some parts for my personal pleasure than to analyze their sound, I have played the album Erdelezi of Goran Bregovic in its entirety. I was moved by the performance of STU versus STX, for example in play Death I was much better a part of the atmosphere, the sound positions being more natural & having as a final result a much deeper satisfaction. The differences aren’t huge, but in the audio system I own, to which I know to the extreme all its qualities & its flaws, wasn’t difficult to identify them.

Besides what’s already stated above, I’ve also found in Xonar Essence STU all the qualities that have made Essence STX soundcard a formidable commercial success: a level of details & micro details without match in the world of soundcards for computers, a clear & well defined bass, without the typical exaggerations of cheap PC solutions & a nice, relaxed presentation of medium frequencies. The voice of Diana Navarro from Imaginando has caressed my hearing with delicacy, reproduction being extremely feminine & with crystal clarity.

Having finished with Goran Bregovic, I felt the need for something romantic, so I have called upon one of my wife’s favorite albums: Dean Martin – Italian Love Songs. Well, this old album from 1962 has brought back into my memory the biggest quality of the soundcards in the Essence series, fully present at the STU version. The sound is fluid, it flows smoothly & it tickles the eardrums delicately. This is a feature impossible to find in the cheap products, be it on-board solutions or entry-level soundcards. To put it simply, these sound poor timbre & dry, as if the sound information is not a whole & is being presented scarcely. Comparing directly Xonar Ds & STU, the latter wins hands on, instruments being better positioned in space, the scene is more believable in front of the listener, this one being much better immersed into the atmosphere.

Being relaxed after hearing Dean Martin, I felt the need for something more rhythm, so I came back in full force with AC/DC – Thunderstruck and Back to Black, Guns n’ Roses – Welcome to the Jungle and Metallica – Enter Sandman. Although the audition itself was a pleasure, especially since I’ve used some very good recordings (Metallica was in 24bit / 96KHz format), I would’ve liked a bit of aggressiveness from STU. The tone was too soft for this kind of music, the high frequencies being a tad too dutiful, intro from Enter Sandman losing its charm.

Rock music brought up a negative point for this card: as the scene grows more crowded, as many instruments play simultaneous in front-raw, the things tend to mix. I forced a bit the situation & I have listened to an album a bit special: Oue: Stravinsky – The Song Of The Nightingale, The Firebird, Rite of Spring (88kHz / 24bit). A reference recording which puts to the wall very expensive DACs & audio systems with good references, this album highlighted some weakness in right distribution of sounds in time & space for the STU. As a comparison, the combo made from M2Tech Young & Palmer (with a street price of around 2.000€) exhibits evidently more details, the sound climbs higher & upper and the level of satisfaction is bigger. In return, bass on Asus is at a very good level, with heavy impact, meaty & well defined.

I’ve continued the listening experience with Maria Maria for the sound of “hot lamp” so specific to Carlos Santana. Listening on STU I had the impression that the hands of the artist don’t touch the strings smoothly, lacking that sensation of real thing, that analogic tone which I found in Muses Edition or in other more expensive DACs; in return, the rhythm was good, since I didn’t experience the congestion of sounds like was the case with the rock music. The acoustic guitar on Xonar STU doesn’t give one goose bumps like in the case of Chord QuteHD (1.200€ retail price), without mentioning the fact that the system used is several times more expensive than the soundcard itself. On a sound system less resolute, these fine details will be missed, like the differences between Burson Conductor & Xonar STU on the Sennheiser HD555 headphones are too small & it doesn’t justify the huge price difference between the two.

I took advantage of the presence of its elder sister Essence One Muses Edition & I’ve made some experiments with the opamps Muses 01. The modification has brought a slight plus in resolution & a better delimitation of the scene’s instruments. If on the top model the difference was bigger, between the stock opamps & those in Muses variant, on the Essence STU, the difference was smaller. Probably the topology of the STU variant limits the potential of the exotic opamps Muses 01 (which cost 50€ apiece).

The headphone amplifier can cope decently with the HD700 model, without bringing this expensive headset to its maximum potential. It doesn’t have the refinement or the raw power offered by exclusive products, such as those from Burson Audio or Sennheiser HDVD 800, but it represents an important asset for those who will use Essence STU with a pair of headphones.

CONCLUSIONS:

Asus Xonar Essence STU is a product which follows in the footsteps of the older model STX, probably the best internal soundcard in the desktop domain. It is not an important upgrade compared to it, but comes with the advantages offered by an external solution, whilst keeping the qualities of the original model. It is worth buying by those who desire a soundcard with real audiophile qualities and top notch facilities & they’re not willing to pay more for the flagship Essence One or pay very much on a dedicated top audiophile DAC.

PRO:

• Good sound presence, a bit above Essence ST/STX series.
• Well made with quality parts.
• Versatility, diversified connectivity.
• Headphone amplifier included.

AGAINST:

• Quite steep price for the consumer segment of the market.
• It doesn’t show up the rate of sampling for the signal received.
• Lack of refinement in some circumstances.

Intro:

Bakoon Products International it is a South Korean company founded in 2009 in Seoul.  It was derived from Bakoon Products Co. Ltd that was established in 1991 in Japan and till 2009 company’s products were selling only on Asian territories. Bakoon Products International was founded to broaden the horizon for promoting products outside Asia, while the products had a face lift and slightly modified circuits.

This article will be dedicated to the headphone amplifier Bakoon HPA-21, the newest product of the company and most interesting one (for me) that they have.

An interesting thing that caught my attention is the topology used in this amplifier. Conventional amplifiers are using as the amplification factor – power in watts. HPA-21 has two headphone outputs, one is a conventional one (voltage output) and the other one is the current output – it uses only current as the amplification factor.

To this day it is the only headphone amplifier that is present on the European market that uses this interesting topology.

Just to make an idea what means SATRI circuit (current amplification is patented and named SATRI) I will try to enumerate few significant advantages:

• Zero distortion from zero negative feedback
• Gain control by the ratio of input resistor R and output resistor RL
• Fixed operating point
• Wide frequency range
• Reliable and stable operation
• Selectable invert or non-invert phase output
• Less than 1/4 in size compared to discrete type designs
• Can be implemented in various circuit designs from amplifiers to measurement instruments

The manufacturer tries to help understand how its SATRI circuit is working by adding this key points on their website:

“The input voltage signal is converted to the input current signal by the input resistor. As the input impedance of the SATRI-IC is close to 0 Ohms, the voltage signal is converted preciously into the current signal.
Then the input current signal goes into the SATRI-IC, from which the output impedance of the signal is converted to above 100 M Ohms, while the current signal itself remains the same. As the output impedance is very high now, the output current signal goes into the output resistor without any loss. By this output resistor, the current signal is converted back to the voltage signal.
Summing up this procedure, the SATRI Circuit’s formula of the overall gain level can be just simplified, meaning that the amplification involves two resistors only. As a result, the circuit is now perfectly linear without uses of any other complicated unnecessary circuits, which would only distort and introduce more noise source in the circuit.”

I can say that in practice advantages of this kind of amplification were noticed immediately. I tried to listen to as many tracks as my time would provide, many of them I didn’t even listed. For nearly two weeks I listened to music of all kinds to make a strong impression about its performance.

Few of the albums listened were:

Gothart – Cabaret, Rakija´n´Roll

Led Zeppelin – Mothership

Luna Amara – Pietre in Alb

Dire Straits – Brothers in Arms

Django Reinhardt – The Best of Django Reinhardt

Silent Strike – 3AM

Trigon – Seven Steps

The amplifier is built as a whole from aluminum with an astounding accuracy, it has two inputs – a SATRI-LINK input (for the DAC that it is in development and for future SATRI sources) and a conventional RCA input.

Build quality is very good, nothing to complain about. The amp is pretty heavy for its size, this being due to Its internal batteries from whom it only can operate. Recharge time is approximately 6 hours and listening time is somewhere between 6 and 8 hours, depending on the volume and the headphones used. Volume wheel is nice to the touch and seems very well built, it works pretty smoothly, it is not a stepped one.

Amplification by current, only battery powered and its price tag of 3000 USD, respectively 3000 EUR brings the product to high-end ranks and in the rows of the top of the line headphone amplifiers at this moment.

Audio performance:

After first minutes of auditioning it was clear to me that it sounds very different compared to what I have listened to this moment. The sound it makes is so different to the traditional amplifiers heard till now that it took me a lot of time to find its weak spots and to make sure that what I am hearing is true.

First and foremost it impresses with the level of detail and its airiness absolutely unmatched by any other amplifier. It doesn’t matter how loud I am listening, the amplifier is distortion free of any kind – a remarkable achievement.

I also want to add that from tens of headphone amps that I tested in the past time the difference in detail presentation of all those amps was pretty small, big differences were in the general audio performance, in dynamics, soundstage, stereo image or background but not so much in the detail department. It’s the first time when I hear so much more information from just changing the amplifier and not the DAC, it’s quite shocking. Sure enough I also did a small comparison to my own benchmark – Burson Conductor.

With Bakoon HPA-21 I felt the limits of the Chord QBD76 HDSD and Burson Conductor DACs, it is quite difficult to express with words the difference between this two amps. To this moment I thought that the amp part of the Conductor doesn’t add any kind of veil and doesn’t hide details because it was among the best to this very moment. When I connected HPA-21 it was like the last layer of veil was lifted from the music I was listening.

The biggest difference between these two amps it’s the level of detail rendered, the size of soundstage and the background. In all those three crucial points I give maximum credits to HPA-21.

With this superior level of detail, that empty space between instruments that I speak of in almost every review became so big that I hear a distinctive pause between every sound, I can easily hear the start and the finish of every sound, that I can firmly say that it has the most contoured sound. It is very revealing, the differences are of course from track to track, one that it is very well recorded will sound excellent with very small differences between both amps, but on a poor recorded track the difference is obvious.

This new wave of information thrown to the listener doesn’t also add a layer of sibilance or fatigue to the music. The music is becoming smooth, liquid, sounds are closely linked, everything sounds distinctive as a whole.

Once with an extreme detail comes also a clear stereo image, to this day it is the only amp that I can give the highest mark in terms of stereo image, I don’t need to close my eyes anymore to see the placement of instruments floating in midair around me, I can clearly hear every audio instrument, where it is coming from and its distance to the listener.

Led Zeppelin doesn’t have exceptionally well recorded albums, but on Bakoon I had an impression that I am listening to a modern recording, without many flaws. The size of the stage and stereo image are going great on this amplifier.

I confirm the companys statement that the amp is the only one that accepts and plays the widest frequency range without any loss. On crowded music I hear new information and new small microdetails that I didn’t know existed, it is quite shockingly to hear them when you think that you listened to those tracks more than a decade. I was listening late at night and when I was hearing something new, I was wincing and started checking if the door is not closed or if something happened around me, I wanted to think it’s a sound in the house, but it was a new sound in the track I was playing. I checked again the tracks and indeed new details reappeared.

Words of praise for the level of detail, wide soundstage and stereo image can go on forever, simply because there is nothing to reproach in this respect.

If at many amps I was telling that the background is black enough, here I can say that it completely does not exist, I just cannot hear it. The lack of a background noise and a very airy presentation are making sounds simply flowing into my face, as if all music played is a river that flows over me.

In terms of general audio performance and if it has a particular coloration, I can say that it is completely neutral and very linear. Listening to HPA-21 It is easy to realize the coloration that other headphone amplifiers have. For me HPA-21 is like a tool to me, like the very best lens of a photographer, like the best tool of an engineer or the best nib/pen of a writer.

Linearity that it is taken to extremes of this amp evidently has a lot of pluses but also minuses, if you are familiar with this kind of sound. People that prefer a more palpable, soft and slow or vivid sound will need to search something different. This one is not colored, meaty, sibilant or very alive, it is precise and doesn’t want to emphasize anything, it is a bit polite and accurately reproduces the signal without adding anything to it. I think it is first amp to which I can attribute motto “wire with gain”. Burson Conductor is different, it colors the music, it cuts a bit of the mistakes in the mastering hiding few microdetails, adding a drop of life and soul to some tracks, it is master of control but it is not as honest as Bakoon.

Speaking about control, HPA-21 has it in spades too. Using LCD-3 on high gain current output I obtained a remarkable sense of control over the drivers. Volume wheel is situated on 09:00 o’clock and I feel already that I cannot go any higher than that.

The difference between low and high gain it is pretty big and this aspect should be taken very carefully. This thing bothered me a little, if on orthodynamics it made a pretty big difference, on dynamic headphones it was an even bigger difference. Just to make yourselves an idea using Sennheiser HD800 on high gain I cannot go louder than 10% of the volume because my ears will start bleeding. On low gain however I can go up to 50% of volume no problem. That is why when headphones are being inserted we should take care about the gain selected. Manufacturer informed me that high gain will be readjusted and 6 dB will be cut from it.

I will speak briefly also about frequency spectrum.

For the bass test I used autochthonous song Elephunk from Silent Strike band. The interesting contrast between electronica and jazz music is very appealing, bass notes sounded precise and airy. It lacked a little impact and weight that Burson Conductor has, but on HPA-21 bass sounded as it had more layers of it. On HPA-21 bass is more precise and clear and not so deep and blurry as on Burson. For electronica and deep bass lovers probably this is not the best choice.

Mid frequencies were rendered accurately and easy on the ear. On the songs of Gothart stringed instruments and the voices sounded warm and pleasant to the ear, strings vibration was accurate without any trace of distortion. On female voices however it still lacked a little warmth and natural vibration of the vocal cords, it loses a bit at naturalness on the mids.

The amp is not part of those warm, slow and nonaggressive sounding amps, this is mostly because of low and mid frequencies that are not projected on the forefront. Although HPA-21 is not aggressive at all, it is neither warm or cold sounding, it is exactly in the middle, trying not to get the attention to itself, trying to completely disappear from the audio chain. It certainly impressed me with its almost invisible audio performance.

Highs were exactly on their places, very well defined, but not sharp or sibilant. The highs were exactly how I would like them to be. The lack of an abrasive sound and its extra detailed presentation that it has on all frequency range makes it a very good choice for instrumental music and all its sub-branches.

A delight for jazz, classical, folk or rock music, I would want a little more energy on bass, but unfortunately you cannot have them all.

Outro:

I was very impressed by the creation of Bakoon Products Internation team. I never expected that a new topology can bring so many benefits and change the presentation of the perceived detail retrieval so much. The difference besides traditional amplifiers is not a small one and from first minutes of listening it is pretty clear that the amp is part of another class. In regards to detail rendering, to stereo image, to soundstage and to absence of a background noise I think that to this moment it doesn’t have a direct rival.

Build quality is top notch, its dimensions are relatively small, design is simple, industrial even, nothing to complain about.

Price is premium, personally I would love to see also a DAC in the same case at this price, but considering the performance, value is justified. If you want the best then this is it.

I thank Soo In Chae this way for trust, amiability and professionalism shown. I’m sure that I will miss the sound of this amp very soon.

Bakoon HPA-21 can be ordered directly from the parent company or from the European distributor Klutz Design

Pros:

–          Details and micro details never heard before

–          Excellent soundstage scale and stereo image

–          Nonexistent background noise, it cannot be blacker than that

–          Fine amplification factor, big power reserve

–          Extreme linearity and neutrality

–          Very good build quality, neat design

–          Battery powered all the time

Cons:

–          Extreme linearity attenuates a bit of musicality

–          Big difference in sound levels between low and high gain

–          Asking price

Gear used for the review:

Bakoon HPA-21, Chord QBD76 HDSD, Burson Conductor, Sennheiser HD800, Audeze LCD-2, Audeze LCD-3, AudioQuest NRG4, AudioQuest Niagara.