SOUNDBOXES VII: GRACE, POWER AND THE VINYL SOUND OF COMPACT DISCS – THE WONDERS OF THE SANSUI AU919 INTEGRATED AMPLIFIER

How can one review the legendary SANSUI AU919 when there are so many superlative labels attached to it already out there on the Web? My take on it: hear it through one’s favourite music. An orchestra should combine power and grace – checked that box with the AU919! A jazz combo should dominate and project an intimate stage – checked that box with the AU919! Crooners and songstresses of the golden era of song should be standing virtually a few feet away from your sweet spot in front of the Hi Fi array – checked that box with the AU919 again! The AU919 brings out all these features on every recording and retrieves – dare I say – the vinyl secrets out of CD! I am not exaggerating. Those of you who are prepared to hear your entire CD collection through Sansui amplifiers will realize that this format has yet to reach the limits of refinement. CDs are not declining, period – thanks to the ‘magical powers’ of vintage Sansui!

 

A Few Technical Highlights Before the Music

Some technical aspects of the AU919 deserve a quick tour in, hopefully, accessible language. As the top model of the AU117-819 series, the AU919 boasts what looks like two separate gigantic transformers (see picture below), one each for the preamplifier, and the power amplifier. That two-in-one-box solution literally generates the illusion that this single amplifier is practically a two box set up intended for the very high end audiophile. This largesse of power certainly takes care of any load your recordings throw at it!

Next, the capacitors. The first photo (left) was taken off a friend’s un-restored, ‘very original’ AU919 showing off the famous Nichicon oval shaped black cap capacitors. Now look at the second picture (below) : four pairs of (tall and short) cylindrical towers (like fuel tanks) arrayed in a row beside the transformers in place of the oval Nichicons. These are the Elna Silmic IIs from what I can see.  This is the version I am reviewing here, and which currently drives my venerable PATHOS FRONTIERS PRIME speakers. Let me quote the original paragraph from the eBay seller (estore.us) who sold it to me:

The unit has all new capacitors on them. All the "Black Flag" troublesome caps were taken out and replaced with a better non flammable high temp ceramic type. All the transistors were checked and replaced where needed. The original output transistors were checked and left in because of their high frequency design for sound. Also, all the resistors were checked for value and were replaced if needed along with all other components. A new speaker relay was installed. New thermal pads were installed on all transistors needing them. All the electrolytic capacitors and main filter caps on this entire unit were replaced with Audio grade capacitors. New audio grade Elna Silmic II audio capacitors filter the main amps the 4 main filter caps were replaced with new Nichicon KG and Super Through Audio capacitors and in the secondary power supply with Elna Silmic II and Nichicon  FG audio capacitors. All the controls were cleaned with Deoxit and work excellent. The bias has been set to the original factory mV settings. (estore.us)

Some skeptics would say that these upgrades might be put in to restore the amplifier BUT at the expense of the sound. To me the truth is the complete reverse! The restored AU919 sounds better than ever! My friend’s ‘original’ set required the ‘Tone Defeat’ to be put on for 90% of the recordings. The bass and treble controls often ‘lowered’ the volume when activated, and occasionally degraded the body of the music. Moreover, the volume had to be turned up to somewhere between the 8 and 9 o’clock positions – this is would be rock concert ‘loud’ to say the least.

My upgraded and restored set rarely required listening at 9 o’clock. The norm was between the 7 and 8 o’clock positions. When tone controls were engaged, there was very little difference in quality from ‘tone defeat’, especially when you engage bass and treble in the ‘+1’ and ‘+2’ regions. Beyond that the treble and bass really kick in – but I don’t really need that since I am not a huge fan of rock music. I’d like to engage the bass in the ‘-1’ and ‘-2’ positions since I am listening in an apartment and do not wish to harass the neighbours in the night with thumping bass up and down the block. But the Elna Silmics and Nichicon KG do their work by adding that deft touch of grace with power.

What about the ‘Jump’ feature in place of the traditional ‘loudness’ button on the vast majority of Sansuis? According to the manual, its simply allows the music to be reproduced from the shortest signal path as shown in this diagram :

I suppose when listening to certain LPs, the Jump function may prove useful in fetching the purity of the music – but unhelpful when listening to Radio (both free to air and streaming) and CD.

Like many other models in this amplifier range, the AU919 offered a multi-voltage capability – some of which could be ‘wired’ accordingly by a good engineer. See this diagram below:    

The final technical detail I wish to highlight is the so-called DD or Diamond Differential circuit touted on the faceplate and in the operating manual. According to what I have read online across various sites such as Audiokarma, this Sansui patented circuit delivers moderate gain on the volume and improves signal clarity resulting in sharper definition of every reproduced note. My ears confirm to me that this is true when I compared the AU919 to its lower powered sibling, the AU717. The 717 grows massively loud the moment you turn the volume knob up just one notch while the 919 adjusts gently notch by notch reflecting carefully the gradations marked out on the volume dial. Unlike the AU717, the 919 came across as demonstrating the inexpressible ‘x factor’ in refinement in every musical item. So there you have it – my non-technical, not too scientific explanation of the DD circuit as opposed to the rest of the AU117-919 range of Sansui amplifiers produced in the 1970s.

Power output: 100 watts per channel into 8 Ohms (stereo) BUT the manual states that if only one pair of speakers is connected to the amplifier it can handle any speaker with impedance from 4 Ohms all the way to 16 Ohms. That just about covers every modern Hi Fi speaker available on the market!
Frequency response: 10Hz to 20kHz
Total harmonic distortion: 0.008%
Damping factor: 100
Input sensitivity: 0.1mV (MC), 2.5mV (MM), 150mV (line)
Signal to noise ratio: 74dB (MC), 90dB (MM), 100dB (line)
Channel separation: 75dB (MM), 70dB (MC), 80dB (line)
Output: 150mV (line), 1V (Pre out)
Speaker load impedance: 8 Ohms (minimum)
Dimensions: 430 x 168 x 428mm
Weight: 21.4kg
Year: 1978-9

The AU919 is being partnered in my ‘test’ with my venerable valve-equipped PATHOS DIGIT CD player and the ORACLE CD2500 CD ‘turntable’ player. Both players are fitted with SILTECH SPX-800 cables which are extremely compatible with high end CD players since they bring out the best dynamics and tightest bass. Interconnects are CRYSTAL CABLE Diamond Standard. Finally, the AU919 is fitted with CRYSTAL CABLE ULTRA DIAMOND for transparency. All the equipment were connected via a simple QRT/Q-Base four outlet US-type mains filter.

 

Smooching Encounters of Vinyl Quality: the AU919 interprets Readers Digest Analogue Remastered CDs

                If you’ve ever wondered what it feels like to ‘hear’ the sound of love sung from the heart, or how a younger version of a favourite singer truly sounded at the height of his or her recording career, you have found the right amplifier. The AU919 ‘answers’ all these questions and more. Those of you who follow my blog will realize by now I am a huge fan of Reader’s Digest music compilations. Tuck into any box set and you will quickly realize that the engineers and compilers behind them put in considerable effort to preserve the stereophonic authenticity of the Vinyl originals in their digital remasters. For this review, I sampled the following tracks from the 1993 British compilation A LOVELY WAY TO SPEND AN EVENING (complete track list available here: http://rdboxsets.blogspot.sg/2014/03/a-lovely-way-to-spend-evening.html) :

96 - Moonglow - Doris Day

97 - Dream - Dean Martin

98 - Bewitched - Jack Jones

99 - Stardust - Roger Whittaker

100 - Quiet Nights Of Quiet Stars - Doris Day

101 - Stranger In Paradise - Johnny Mathis

102 - Stars Fell On Alabama - Vera Lynn

103 - A Nightingale Sang In Berkeley Square - Perry Como

104 - Stella By Starlight - Tony Bennett

105 - Somewhere - Andy Williams

106 - When You Wish Upon A Star - Matt Monro

107 - Reach For The Stars - Shirley Bassey

Doris Day’s sultriness epitomizes the mood in ‘mood music’ after you’ve heard the above on the AU919. Her voicing of the lyrics is sincere, teasing and sexy, all essential ingredients in making a classic love song. Vera Lynn’s diction is delectable and worth putting on repeat! Johnny Mathis’ vocals alone demonstrate a silky orchestral feat that rivals his instrumental backing. Tony Bennett conveys his Italian panache in singing extravagantly extended notes, while Matt Monro brings a new aura to stereo with his nasally inflected style of rendering ballads. The biggest surprise is perhaps Shirley Bassey who sounds like a totally different persona in these ‘younger’ recordings. There is an audible silky edge to her tone that one does not hear on her later recordings from the 1970s onward. It might be due to her age, or the techniques of recording changing from decade to decade, but certainly the original vinyl on which these tracks were first cut does not lie – at least not to me. Switch to the American Reader’s Digest compilation from 1996 titled SENTIMENTAL SONGS THAT WILL LIVE FOREVER and once again the AU919 astounds you with its audio revelations of the quality of the vocals from the 1950s and 1960s of the calibre of the Pete King Chorale, Helen Forrest, Vaughn Monroe, Ed Ames, Margaret Whiting, Jo Stafford, Ken Barrie, the Roland Shaw Orchestra and chorus and other stalwarts of ‘the golden age of song’. There is something evergreen about these voices that make you want to listen to them again and again – on the AU919. These fine performers command the lyrics and convey them to you with sincerity on every word. For good measure, I added one other favourite singer to the test queue: Rosemary Clooney’s BRAZIL recorded in the early 2000s. I wouldn’t describe her voice as silky or velvety but it was an indescribable poignancy that tugs at your sonic heartstrings. Every note Rosemary sings seemed inspired through the window she was metaphorically gazing out from high above the night lights of Rio de Janeiro. The AU919 evokes that sort of ‘magic’.  

                I dabbled with two more ‘stars’ from my blog of classic orchestras: Henry Mancini’s MARTINIS WITH MANCINI, a BMG/RCA compilation from 1997 and Paul Mauriat’s Japanese remasters of the LPs PREVAILING AIRS and LES TEMPS DES FLEURS on the PHILIPS Japan label. The AU919 confirmed to my ears’ delight that it was indeed the master interpreter of original analogue recordings. MARTINIS WITH MANCINI was a compilation of 60s style Latin-infused lounge tracks for formal dinner parties set up around syncopated percussive rhythms and prolonged solos by saxaphones, pianos, trumpets, harpsichords and xylophones. It was meant to be an intimate sort of party music. Through the AU919, one hears everything in place – the insistent, tightly scripted congas, drums, accordions, cymbals etc. – laid over with assorted soloists invited by Mancini to perform the sonic equivalent of a cha cha, samba rock, the occasional rhumba and twist and so forth. Music indeed to put you in the mood to take to the dance floor or sip martinis while watching the crowd. Paul Mauriat came alive in the virtual studio on both Japanese remasters. The bass on ‘L a Pioggia’, ‘Oh Happy Day’, ‘Sweet Charity’ were spot on and redolent of the exuberance of pop styles in the late 1960s. The only complaint – albeit a minor one – was that the track ‘Say a Little Prayer’ was over the top with the bass if left uncontrolled. For this one, Tone ‘On’ was absolutely necessary with bass adjusted to ‘-1’ on any setting on the bass knob. Other than that, Mauriat’s arrangements exhibited their flamboyant movement and dynamics as they were expected to – track after track. The theme from ‘Chitty Chitty Bang Bang’ showed off how Mauriat could pull off a Philip Sousa-like March and make it his own ‘hit’. Other revelations include the carefree ‘summery’ ambience of ‘Try to Remember’ with its distinctive piano lead, and the sensitive ‘Valse D’Ete’ and ‘Irresistiblemente’. In short, the AU919 more than does credit to these original stars of Vinyl EZ listening.

AU919 – the Classical Maestro? Airs and Living Presences Aplenty

                Finally, I put on music in the genre of the Classical/Opera as the ultimate test. The vast majority of classical recordings available in the market were made ‘live’ or ‘unplugged’ from the 1980s onwards. Moreover, European music composed in the period 1500s to 1800s were meant to be played in one’s physical presence. Witness for instance, the opulent music rooms in preserved palaces in England, Spain, France, Austria, Italy, Denmark and Germany etc. So logically, one’s ears should be hearing an authentic replica of a live performance.

                I tried the gentle tones of Luigi Boccherini’s Guitar Quintets Volume One (Naxos label) first. The result coming out from the PATHOS speakers was very convincing: the intimate ambience of a Baroque performance was extremely inviting. I was not committed to this composer’s works beforehand but I wanted to hear every note just to indulge in the purity of sound reproduced in my living room over and over again. I switched to a mixed instrumental and vocal classical music compilation – A LOVE SO BEAUTIFUL 2 on a Sony-BMG-Universal exclusive release to THAT CD shop in Singapore – and the results were equally sublime. Peter Aronsky’s innovative reinterpretation of Mozart’s Piano Concerto No.21 was uplifting and haunting by turns with its soprano-choir-piano arrangements. Lesley Garrett’s ‘Greensleeves’ was filled with mirth and coyness in equal measure. The Celtic Tenors piqued one’s sentimentality with ‘Love of my Life’ with vocal catharsis going into overdrive! And this was not even a ‘standard’ operatic aria. I next tried Placido Domingo’s FROM MY LATIN SOUL from 2004 and the sonic revelation was no less intense. In fact, I was half expecting a blast from Domingo’s tenor on the scale of a Bocelli or Pavarotti, but the AU919 conveyed his voice differently. Domingo was in his own vocal limelight: his was a voice you’d like to hear emitting local colour in Buenos Aires, Bogota, Puerto Rico or Mexico City. It was warm, with a slight touch of warble to the tone, in a very good way. In fact, Domingo’s entire album was a veritable tour of Latin America through one finely tuned voice.

The AU919 as a Classic in its Own Right & Other Comparisons

                Simply put, the AU919 is the all rounded integrated amplifier that I (and perhaps you the reader) have always been looking for. While this review may have been enhanced with the use of CRYSTAL CABLE power cords and interconnects, and some very high end CD players, it was worth it. This review was based on the principle of musical transparency: the amplifier should reproduce what the best sources can! Indeed it has convinced me this is an amplifier one should consider keeping for life. It is also to the credit of PATHOS ACOUSTICS of Italy that they have manufactured such a dynamic set of loudspeakers that match the rich sound of the SANSUI. In case you are curious, this is the FRONTIERS PRIME model that is capable of tri-wired cable connections.

                An additional question that some readers might ask is : how does the 919 compare with the lower numbered AU717 boasting 85 Watts? If you have both, and have the space for both, keep them! The AU717 was my first taste of the series.[Note the 717's double transformers in the picture below.] As I had stated earlier, the 717 comes across as the ‘higher volume gain’ amplifier when you adjust the volume upwards. The 919 is much more precise in its volume rates. The loudness of its output does not jump significantly from one rating to another, it is gentle and gradual. If you need the sound to rock the room, or a fairly large hall, at slightly higher than normal volumes while still enjoying tight bass, the 717 may appeal slightly more to your tastes. Comparing the same vocals tested above, the 919 was much more refined after some attentive listening. The 717 conveys room filling nostalgia with almost immediate sensation, so you might not notice anything amiss with a blast of volume, while the 919 requires tuning the volume carefully before you smile to yourself and say ‘this is it’. For the majority of instrumentals, the 919 was always slightly ahead in ‘scrubbing’ (if I may use such a term) the original recording of any colouring due to age or other technical drawbacks. But both the 717 and 919 sound equally warm and full bodied in reproducing music, exactly as vinyl recordings should. They are like two different versions of a fine wine from the same brand.    

                What about the other two derivatives in between, i.e. the AU719 and AU819? Both are ‘descendants’ of the Diamond Differential (DD) circuitry premiered in the AU919 but boasting slightly lower power i.e. less than 100 Watts. Additionally, both offer SANSUI’s characteristic loudness switch perfect for enhancing bass at low listening levels. The AU919 does not have this – and I feel it does not need this given its finely crafted volume gain. I have not physically listened to the AU719, but I have had a passing encounter with the AU819 in my usual second hand hi fi shop in Singapore. The AU819 was demonstrated to a customer while being matched to a pair of moderately easy to drive FOCUS AUDIO MT-1 loudspeakers. I noticed that its volume knob needed to be  turned up to somewhere between the 10 and 11 o’clock position while I have hardly turned the AU919 volume beyond the 8 o’clock position. Maybe it was a difference in speaker qualities, but then the SANSUIs have never been known to lack power in any set up. This sample of the AU819 was completely original and boasted 90 watts. Then again, it could be the case that it did not have two transformers – unlike the AU919 – but it was a hefty single transformer. The unit was also unrestored and the capacitors – I am told by some very reliable engineers – could indeed be showing their age.

                All in all, one can’t possibly go wrong in extracting jaw-dropping vinyl-like sounds from CD with the AU717, AU719, AU819 or the AU919. In its heyday, SANSUI never stopped experimenting with circuitry and kept perfecting different versions of their most popular amplifiers. Even their oldest models have some kind of ‘edge’ in their vintage which their later cousins will never quite possess. If I have the time, and money, I would definitely like to sample something from every one of their product lines….But, coming back to reality, the best point to remember is to buy them restored in order to hear them in as pristine and optimal a condition as possible. And they should last at least 30-40 years – this is true vintage.

ALAN

April 2016