Explorations in Audio

Karsten Hein

Are you ready to Explore?

In 'Explorations in Audio' I aim to share some practical insights on setting up and optimising an affordable HiFi system. Although one would think that, really, all has been said about HiFi, some surprisingly simple questions still remain, e.g.: 'Is digital superior to analogue?' 'Do cables matter?' 'Can digital cables pick up interference?' 'Should speakers be placed on spikes?' 'Has evolution in HiFi made older gear obsolete?' 'Where should I place my sub?' 'Which room correction works best?' - On the other hand: 'Are these really the right questions?' - We shall see.

What’s new in eiaudio?

While the entries in this blog are divided into the three distinct categories above, you will find a mixed listing of the most recent postings below. The most recent article is shown first. If this is not your first time visiting, the listing below is a good place to quickly check if anything is new.

Your input is more than welcome, as long as you follow the basic audiophile rule of ‘ear over mind’. This means that you do not comment based on what you think you know, but only on the basis of your own listening experience. Please feel free to suggest gear for testing as well as leave comments on the descriptions provided here.

  • Turntable Cover Restoration

    Turntable Cover Restoration


    Author: Karsten Hein

    Category: Explorations

    Tag(s): Restoration, Turntables

    We might as well face it: Turntable covers have always been little more than a necessary evil. It seems that manufacturers—while suffering great pains in designing their beloved machines—were unable to think of anything more exciting than simply slapping a semi-translucent dustcover on top. And, typically, this cover was made of some easily scratched acrylic compound. For those of us searching for or selling vintage turntables these days, a scratched dustcover often meant a substantial degradation, not only in terms of attractiveness, but also in price.

    Since the non-profit nature of my eiaudio testing series had made me rather price-conscious myself, I could not help but wonder just how much effort it would take to restore a scratched dustcover to its original splendour. The idea of being able to do so myself did seem attractive to the explorer in me. After all, this would enable me to take advantage of the potential price discount granted on the scratched cover, while being able to do the restoration myself. Hence, I contacted a friend, who also happened to be a specialist in automobile restoration, to help me find the best strategy for my project. Thomas was intrigued by the idea of restoring acrylic plastic and took the badly scratched dustcover of our Thorens TD 320, a turntable I had purchased some weeks earlier, to his repair shop.

    Thomas returned the cover to me in mint condition just two days later and informed me which equipment I would need to purchase in order to complete this type of restoration by myself. I took note of his advice and placed my order on the same day.

    Inventory Needed

    • orbital sanding machine
    • sanding paper, grades 240 - 3000 (240 / 320 / 400 / 600 / 800 / 1000 / 1500 / 2000 / 3000)
    • orbital polishing machine
    • polishing pastes in grades fine & extra fine (e.g. 3M ‘Green cap’ / 3M ‘Yellow cap’)
    • one large microfibre cloth

    The total tab would have set me back around 300.00 EUR, but, since we already had an orbital sander in the household, I only needed to purchase the various grades of paper and the polisher with the corresponding pastes and cloth. Thomas thankfully offered to keep me company during my first sanding attempt. On his advice, we took our little sanding project outside. This gave us cleaner air to breathe and protected our household furniture from the fine sanding dust.

    The dustcover to be restored was of a 1978 Dual CS 721 turntable. Next to the typical house cleaning scratches, it also showed two lines of approximately 1mm in depth and 20cm length which had most likely come from piling other items on top of the unit during its years of storage. We discussed the most appropriate choice of sanding grain and decided to start from 320. If the scratches had been any deeper, we would have probably started from grain 240 to be on the safe side.

    We positioned the turntable cover on an even non-slip surface and placed the sander firmly on top of it. The speed dial was set to medium revolutions in order to keep the temperature low during the process. If the temperature became too high, the cover could easily become stained or deformed. The sander was placed on the surface with the motor turned off, and it was turned on only when securely in place. This way, there was less chance of the paper’s sharp edges accidentally cutting new scratches into the surface.

    Thomas explained to me that the machine would need to evenly sand the whole surface until reaching a ‘level 320 sanding result’. (Note: Be sure to keep your fingers away from the paper edge, as this can indeed be quite sharp and easily cut into flesh.) Starting from grain level 320, the turntable cover did become opaque at an instance, and we knew that it would take some time for it to become translucent again. On the positive side, we could watch the deep scratches gradually disappear. We had peeled the Dual logo off with a screwdriver before sanding, and we made a point not to polish the edges of the small cavity where the logo had originally been placed.

    Thomas insisted that we take the time to fully complete each step of the sanding process, thus working our way up from 320, to 400, and then to 600, until all the steps to 3000 had been completed. At each level, we made sure that the surface was fully restored to the level characteristic of that grain. We stayed out of the sun and took breaks to keep the material temperature low. At grain level 3000, the surface started to become translucent once again. We inspected the final result by wiping the surface with the large microfibre cloth.

    Once we were happy with the sanding result, we exchanged our sander with the polisher. Thomas explained that it was best only to use small amounts of polishing paste, as this would otherwise splash about in a circle. As we had done during sanding, we turned the machine on and off while it was in contact with the turntable cover. Thomas showed me how to apply even pressure in order to achieve a uniform result over the whole surface. I saw that one small scratch we had missed in the early stages of sanding also managed to survive all the stages of further treatment. To me, this only highlighted the importance of a very thorough first sanding.

    We checked the polishing result from time to time, until no further progress could be made using the '3M Green' cap paste. It was only then that we changed to the '3M Yellow' cap paste for that final high-gloss polish. Pleased with the result of our work, we found ourselves ready to tidy up the scene of the action approximately one hour after we had started. One hour’s work is probably a good estimate for anyone doing this the second or third time around. I was lucky that I had the help of my professional friend who had made sure I took the correct time and followed all the steps necessary. First time polishers would probably be best off to calculate with 2-3 hours of manual labour.

    I hope you will find this account of events helpful in your own restoration project, even if it is only to help you better appreciate the prices charged by professional restorers. Do feel free to leave a personal comment below. With 'Hyvor Talk', we have recently made social engagement on this platform far easier. — Enjoy.

    Click here to see the full video

    Jörg Hegemann
  • Epicure EPI 500

    Epicure EPI 500


    Author: Karsten Hein

    Category: Gear & Review

    Tag(s): Loudspeakers

    Although the brand has largely been forgotten by today’s Hi-Fi enthusiasts, there are few names in vintage Hi-Fi that make the audiophile heart grow fonder than that of Epicure. The company’s focus in loudspeaker design was on providing natural tonality and imaging, and it often went to great lengths in the pursuit of this aim. Its founder, Winslow Burhoe (a former apprentice at Audio Research), had originally set out from a 2-way speaker design, which he named ‘the module’, and designed a whole range of loudspeakers around this. The Epicure 'Model 20', for instance, used two sets of 'the module', which were positioned invertedly to form a dipole and resemble live-stage characteristics. The idea was to incorporate the listening room’s front wall for acoustics effect. A similar design was also used in the EPI 'M 201' loudspeakers. These early specimen were well-received by the audio world and aimed at the higher end of the market.

    The EPI 500 were among the first Epicure loudspeakers to break with the traditional module design. Instead of being based on Epicure’s tested 2-way principle, the EPI 500 were a classic 3-way tower speaker featuring specialist drivers to cover: the high notes, the critical midrange, and the bass frequencies. While essentially being of a closed-cabinet design, the EPI 500 extended their cabinet volume with the help two passive radiators, one placed on each of the speakers' side walls. These served to absorb the woofer’s inward energy and also supported it in the area of low-frequency extension. (Passive ratiators have again become attractive in modern times, in the sense that they provide considerable bass extension to Bluetooth convenience gadgets made by JBL, Bose, etc.) The Epicure's top-end was based on their signature inverted-dome gold ring tweeter. Where other high frequency drivers would have their domes facing outwards, Winslow Burhoe had made a name for himself using an inverted face-plate design, which gave the tweeter some horn-like compression characteristics. The tweeter on our specimen was of the second generation air-cushioned, oil-dampened design, a fact that would have placed the most likely construction year of our pair in the mid to end 1970s.

    I purchased our EPI 500s from a private vendor in Nürnberg, who had in turn bought them a few years earlier in order to listen to his extensive vinyl collection. Having had troubles with the engine of our car on the way to Nurnberg, I arrived there in some disarray, kept wondering about my risky journey home, and therefore found it rather difficult to focus on the music. We listened to two or three songs, I held my ear on the drivers to check for potential noises that should not have been there, and concluded that they worked just fine. I did notice that one of the midrange drivers showed a slight smell of burnt coil-resin, but since I could not detect any scraping sounds emenating from it, I decided to trust the seller’s own verdict that he had not noticed any faults with the speakers himself. Epicure speakers were well known to stand the test of time, unless they had been over-driven for extended periods. The 40-something year-old woofers looked as though they had been re-coned, and I was relieved to see that the work had been done with care.

    While heaving them into the car for my ride back to Frankfurt, I noticed that—despite their modest size for tower speakers—they were surprisingly heavy, and I was grateful for the helping hand offered by their previous owner. 250 kilometres distance could seem long when seen from the perspective of a broken car that was blowing black diesel fumes out its back. As one might imagine, I made good use of my time going through different scenarios of having the car and speakers toed home that day. Lucky enough, I managed to make the journey back with the engine in its last twitches and unloaded the speakers before finally taking our vehicle to be serviced. This was commitment to the cause all the way through, of course. But then again, I was confident that the Epicures deserved no less.

    When I finally returned home to further investigate the EPI 500, I noticed that they had one additional feature that I had noticed in the very beginning of my research and then somehow forgotten about: There was a wooden base screwed in place that formed a closed acoustic frame underneath the cabinet. This raised each speaker off the ground by about 8.6 cm. The base was needed to elevate the tweeter to ear-level, but it also prevented the speaker terminals from touching the ground. There may have been a number of reasons for positioning the terminals underneath the loudspeaker, e.g.: to make the back of the speakers look cleaner; to allow for the attachment of invisible sub-floor cabling; or simply to make unobstructed use of the cabinet's resonances. Holding my hand to the side and rear walls of the EPI 500, I could feel that this cabinet had been designed to naturally incorporate resonances with its sound signature, instead of bracing against internal and external vibrations in the way modern speaker designs would.

    Understanding how the EPI 500 dealt with inherent resonances would be vital to finding the correct placement and integration in the room. However, with the whole cabinet and passive radiators set in motion at once, I also saw that success would not come easy. I would have to put myself in the position of the designers and imagine the most probable environment that they had envisaged for their speakers to perform in. This, of course, was likely to have looked and sounded differently from our sleek office with white high-gloss furniture and scant carpeting. Luckily, the underlying architecture of our building itself was not all too different from the typical American home of the 1970s and 80s, in the sense that our room was located under the roof of the building and of poorly insulated wooden beams that were planked with gypsum and plywood boards. This would most likely help to absorb some of the excess bass energy, if needed. I also discussed the matter with my audiophile friend Luigi who reminded me that the base had probably been designed with American highfloor carpets in mind.

    The base of the EPI 500 had a small hole describing a semicircle towards the floor through which one was to run the speaker cable. To keep the base from touching the ground, some previous owners had glued small rubber pads of 1mm thickness and 20mm width into all four corners. I did not know, if this had been found a good idea and decided to listen to the speakers in this condition first. Our testing system consisted of the Restek V1 preamplifier with upgraded Kassel power supply and the B&K ST-140 power amplifier. As sources, I used our Technics 1310 turntable and Marantz CD-17 player paired with Cambridge DAC. The interconnects were of solid core silver, and the speaker cable was our affordable but effective Belden 9497. This was a Hi-Fi setup that I could trust in terms of sonic integrity, having listened to each of the components in many different constellations. Naturally, I was intrigued to learn what the EPI 500 would add to or take away from the balance of sound.

    Perched on the hardwood floor with the 1mm thick rubber plates in place, the speakers sounded dull and lifeless. I felt compelled to visually inspect the tweeters just to see if they had perhaps been damaged during transport. They looked fine. I also noticed that the ground in our office was not perfectly even so that the base did not manage to press down firmly enough on all sides. As I had expected, the smallish pads could neither offer a defined coupling nor decoupling from the ground. They somehow did both, and this confusion was audible. To learn more about the situation, I scraped off the pads and placed the speakers directly on the floor. With wood piled ontop of wood, the whole floor was turned into a resonator, and the resulting sound was overly wooden and muddy. To experminet with the opposite direction, I then placed our ultra-hard metal ball Aucharm absorbers underneath the base. This did serve to accentuate treble, but, as a consequence, the EPI 500 now sounded overly analytical and were lacking bass.

    At this stage, I could already hear that the speakers had some potential, and that the optimum solution would need to provide the right mixture of dampening and stability. To make this possible, I lined the bottom of the base with felt towards the floor. This improved tonality, but I still had problems with imaging, possibly resulting from the slightly uneven floor. Thinking about how to address this issue, I added three 5mm-thick and 40mm-wide felt cushions: two on each side at the front, and one in the back. The hole for the speaker cable got in the way here, but I decided that a few centimetres off axis would not matter to the rear support. I then sat down to listen and was relieved to find that both soundstage and tonality had much improved. The EPI 500 produced a full and open sound that was also tonally rich. The double-bass on Diana Krall’s album “Turn up the quiet” now had lots of zest and dimension. I was not yet happy with the depiction of Diana's voice which was represented softer and less assertive than I was otherwise used to. Placing a second felt cushion on the other side of the speaker cable hole in the back went some way of solving issue. Possibly, the enhanced sound could be attributed to the improved balance in the support between the speaker's front and back.

    In positioning the speakers, I found them two work well with the mouth of their drivers at 109cm distance to the front wall of the listening room. This was a placement that should also be possible to achieve in most listening scenarios. The speakers were placed just under two meters apart, measured from axis to axis, and my listening position was similarly at around two meters distance measured in diagonal. I found the tweeters and midrange to work best with the tweeter’s output axis crossing at least one third behind the listening position, instead of being pointed directly towards the listener. I have found this to be the most enjoyable setup with many speakers, but this might just have to do with my own listening tastes.

    In this setup, I found the EPI 500 to offer a highly natural and informative mid-band. Their ability to reveal lots of nuance and layering in this tonal segment would have made them an instant darling with audiophile listeners. More generally speaking, the Epicure’s ability to incorporate thei cabinet's resonances and passive radiators into the music output made them an excellent companion for natural instruments as found in Jazz, Folk, Country Music, etc. However, I found that the obvious strengths of the mid-band did not automatically translate into an outstanding depiction of voices. From my own perspective, our more modern Tannoy XT8F managed to offer the tiniest bit more in terms of believability in the midrange. I would have had to run further tests to learn if voices could be improved by adding solid steel plates in between the base structure and the felt pads in order to increase stability. I had a strong feeling that structural instability towards the ground might have been the culprit here.

    Going through forums, I had read that some people suffering from tinitus were complaining about listening fatigue in connection with Epicure speakers. This phenomenon may have had to do with faulty coupling to the ground, with high feequency infiltration, but also with the shape of the inverted-dome tweeter itself. I noticed that this could produce a slight compression effect and thereby make the music seem quite dense in the treble. I also noticed that I tended to listen to music louder than I would have done with our other speakers. It was easy to get carried away while listening to these speakers, as I found out when putting on our 2009 pressing of Fleetwood Mac's 1977 album "Rumours". I simply enjoyed listening to the intense tonal richness that I had sometimes missed before.

    In comparison to my first experiments with the EPI 500, bass performance had tripled, thus providing me with the realistically full sound and satisfying punch of an excellent tower speaker. Imaging was excellent, with a naturally wide and unconstrained center image. The music was well-spaced: from front to back and from left to right. Voices were still a touch on the sweet and soft side, but we would need to see about this aspect in the long run. From my experience, the EPI 500 should be easy to drive from a 20 watts tube amp, as well as a beefy solid state amp. They took some time in setting up properly, but the additional effort was well-worth it. Perhaps the aspect that I enjoyed most about them, was their ability to provide a Jazz club atmosphere with freely breathing natural bass, but without the smell of cold cigarettes and stale beer.


    • Type: 3-way dynamic speaker
    • Design: closed cabinet with passive radiators
    • Impedance: 4 Ohms
    • Power handling: 250 watts (max.)
    • Frequency range: 45 Hz - 20,000 Hz (+/-3dB)
    • Tweeter: EPI gold ring (2nd generation)
    • Tweeter principle: 2.6cm invert-dome, air-cushioned, oil-dampened
    • Midrange driver: 10.5cm, paper cone (1st generation)
    • Bass driver: 25.4cm, paper cone
    • Passive radiators: 30.4cm
    • Crossover freq.: 750-3,000 Hz
    • Cabinet finish: walnut
    • Dimensions: (H) 91.44 cm, (W) 30.48 cm, (D) 35.56 cm
    • Weight: 28.12 kg (each) 
    • Country of manufacture: U.S.A.
    • Year(s): 1973 - 1981

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  • Fase Performance 1.0

    Fase Performance 1.0


    Author: Karsten Hein

    Category: Gear & Review

    Tag(s): Integrated Amplifiers

    For far too long, I had harboured the suspicion that integrated amplifiers were ill equipped to captivate our imagination to the same extent that separate units could. However, I must confess that this was mostly true in the years before I had ever heard a well-constructed integrated amplifier at work. Perhaps my misguided opinion had originated from the fact that I had mostly known integrated amplifiers from the run-of-the-mill gear sold by electronics superstores or your average online discounters. Since this had mostly been price-driven equipment of the kind that followed current market trends, audiophile pleasures were hard to come by.

    Luckily, the sleek-looking Italian amplifier that is the subject of this review had an utterly different story to tell. Instead of having been a mass-market product, the Performance 1.0 was designed and manufactured by Fase Evoluzione Audio in Italy, towards the end of the 1990s. It was to a great extent based on the craftsmanship and engineering philosophy of Fabio Serblin. Fabio himself was the nephew of the legendary Sonos Faber founder Franco Serblin and had previously designed the rather successful QUID amplifier for the Sonos brand. Fase Audio products, too, were created for the audiophile market, manufactured in small numbers, and of higher than average quality.

    The Performance 1.0 was based on a simple circuit board design that was in keeping with the audiophile 'less-is-more' philosophy. The unit’s 60 watts per channel came from a decent-size low-noise toroidal transformer and four high-quality Phillips capacitors. The pair of power transistors per channel were of the Mexico-made Motorola 'MJ15022' type. The unit's front panel featured input and recording selectors, as well as a high-quality Japan-made Alps 'Blue Series' potentiometer for volume adjustment. The Performance 1.0 offered excellent RIAA correction for phono and was even capable of handling higher output MC cartridges. The rear panel featured solid speaker terminals for spades or bananas, a convenient IEC power socket, and a ground-lift switch that could come in handy in case of humming or similar grounding issues in connection with other equipment.

    The unit’s sides were tastefully flanked by solid wood panels, a measure taken to dampen the effect of transformer humming on the electronics and housing. The overall design was of Italian understatement and crude simplicity. For example, the screws that secured the top and bottom of the cabinet were visible from all sides. Even the wooden panels themselves had visible screw heads peeking through. Perhaps this was done with the aim of highlighting a Bauhaus 'design-follows-function' philosophy, or it was simply to keep production costs during the assembly in Italy down. Even when I was not listening, I could not help but glance over to the position where the Performance 1.0 was standing from time to time, wondering what Fabio Serblin had been contemplating when he designed this unit. And so it happened. I had finally come across an integrated amplifier that did captivate my imagination

    I would have normally started my listening journeys with CD as source and then turned to phono once I had developed a feeling for the dynamics and dimensions. However, this time around, I started out by connecting our trusty Dual CS 505-3 to the Performance 1.0. The Dual, with original Ulm cartridge, had just been revised and fitted with cinch/RCA connectors, improved isolating feet, and new drive belt. I loved this simple Dual player for the no-frills attitude with which it presented music and really did not expect too much from the Performance 1.0. All the more, I was surprised how well the little amp highlighted the Dual’s inherent strengths by contributing to its clean and honest sound. If at all, the Dual seemed a little smoother than before, and it also seemed to pack more punch. Despite its modest dimensions, the Italian did not sound tiny or frail at all. It presented its music with great tonal richness. Bass was full, perhaps a little more on the thumping side than deeply extended, but nevertheless instantly amiable.

    Katie Melua’s “Album No. 9” was presented with a slightly fuller voice than I was otherwise used to. This actually served to make the sometimes overly revealing and at times even harsh and sibilant recording more enjoyable. On the downside, vocals did sound less alive, realistic and airy. Bass notes had a slight thickness to them and were more soothing to the ears and body than analytical to mind. This effect may have been accentuated and accumulated by our choice of low-capacitance silver solid-core interconnects and Belden 9497 speaker cables or by the resistance combinations of the devices. In and of themselves our Tannoy XT8f speakers and Dual CS 505-3 turntable were not known to be lacking in top-end or transients.

    The impression of a mild top-end congestion, perhaps for the sake of reaching a fuller sound, remained unchanged when I made the transition from vinyl to CD. One thing struck me as particularly odd: On our current testing system, we were running a Cambridge DacMagic 100 in conjunction with a Marantz CD-17. All connections were based on solid-core silver cables. The DacMagic had an output impedance of 50 Ohms, and this simply did not match the Fase Audio’s expectations. Taking the DAC out of the equation, I was able to raise output resistance to 250 Ohms. The improvement was instantly noticable, however, I made the mistake of also changing from our silver solid-core interconnects to an older pair of Fast Audio interconnects. For direct comparison, I should have just changed on thing at a time. Finally, changing back to our silver interconnects, I found that this created an even more natural top-end with vastly improved transients. The result was highly enjoyable, although I now noticed that the stage still seemed a little flatter and more recessed than I was used to. Such is the nature of our hobby that when one phenomenon is understood and put aside, the next one pops up from underneath, thus presenting another riddle to be solved.

    However, further exploration will have to wait for another day. This particular Italian is going to play its tunes at Landon's house. Landon has been doing the proofreading for eiaudio and has been waiting for a proper amp to power his system for the longest time. Given some further exploration and clever matching, I can see the Performance 1.0 becoming the trusted heart of a passionate home Hi-Fi setup. With four line inputs and one very capable phono input, as well as lots of cross-recording functions, the elegant Italian offers the looks, power, and tonal richness that one would expect to result from a family production that has long since become royalty in Italian Hi-Fi. And although Fase Evoluzione Audio closed its doors some years ago, Fabio continues to manufacture Hi-Fi equipment under the brand of Serblin & Son. His uncle Franco of Sonos Faber died in 2013 leaving behind a flourishing loudspeaker manufacturing business. His life and achievements are commemorated by Serblin and Son’s through their current range of Hi-Fi equipment that is simply called — ‘Frankie’.

    Note: Before handing the Performance 1.0 to Landon, I had the chance to test it on our newly aquired vintage Epicure EPI 500 loudspeakers. Playing in conjunction with the 4 Ohms EPIs, the Fase Audio seemed instantly more at ease and was able to drive them with superior tonal balance. The formerly punchy bass blended more seemlessly into the music. Following this experience, I would personally give preference to a 4 Ohm speaker to reach the Performance 1.0's full potential.


    • Type: integrated MOSFET amplifier
    • Signal to noise ratio (line): 98 dB
    • Signal to noise ratio (MM): 70 dB
    • Signal to noise ratio (MC): 65 dB
    • No. of input(s): 4x line; 1x phono
    • Volume control: Alps ‘Blue Series’
    • Outputs: 1 pair speaker terminals (bananas or spades)
    • Power output (8 Ohms): 60 WPC
    • Power output (4 Ohms): 100 WPC
    • Features: ground lift switch
    • Dimensions: (W)42.5 x (H)7,5 x (D)32 cm
    • Country of manufacture: Italy
    • Weight: 7.5 kg
    • Year(s): 1995-1997

    80s night
  • Pioneer SX 850

    Pioneer SX 850


    Author: Karsten Hein

    Category: Gear & Review

    Tag(s): Receivers

    Paionia Kabushiki-gaisha, a Japanese company henceforth referred to as Pioneer, has evolved to be the heir of a long legacy of outstanding professional and domestic electronics. And although receivers made up only a small fraction of the company’s success story, they did serve to promote the Pioneer brand in Europe and the USA. Pioneer is sometimes said to have spawned the infamous ‘Receiver Wars’ during the Golden Age of audio in the decade spanning from 1971 to 1981.

    The ‘Golden Age’ of audio is sometimes referred to as such, because consumers in this era were willing to spend a considerable portion of their income on advances in Hi-Fi, thereby giving manufacturers the financial resources to incorporate long-lasting quality components, and the freedom to conduct intensive research in order to build the best devices they possibly could. In those days, the market was still dominated by privately owned and research-driven companies that were fighting for pole position in the newly emerging Hi-Fi magazines.

    Pioneer was a case in point. Owned and operated by the Matsumoto family, the company already had a thirty-year history in manufacturing audio electronics by they launched the SX 850. The concept of an all-in-one control unit that included tuner, preamp, and power amplifier had originally been invented by the American Harman Kardon corporation during the 50s. However, Japanese manufacturers, such as Marantz, Sansui, and Pioneer, followed suit and soon rivalled Harman Kardon in terms of quality, performance, and especially cost.

    Despite having established a strong manufacturing base in Japan, Hi-Fi receivers continued to be mostly manufactured for and sold in the United States and Europe, as Japanese audio enthusiasts preferred the sound and versatility of separate units over the combined package. Customers in western countries, on the other hand, enjoyed the fact that they could get very close to the performance of separate units while having to put up with less than half the fuss. It may have also helped sales that most receivers featured large illuminated scales and fancy looking front-panel designs that increased the wife-acceptance-factor.

    On the downside, receivers usually offered less power than separate amplifiers. Or at least this was the case before Pioneer, staying true to their name, released the world’s first genuine 100 watts per channel receiver. This was even certified by the United States Federal Trade Commission (FTC) that had started to regulate the audio market, due to an increase in false promises on the side of manufacturers. Released in 1974, the SX-1010 was Pioneer’s (then) flagship receiver and out-performed the competition by almost 40 watts per channel. Unfortunately, the glory turned out to be short-lived. In August of that same year, the Japanese Marantz corporation followed suit with their legendary 2325 model that boasted 125 watts per channel. The receiver wars had officially begun, with each manufacturer aiming to out-perform the competition in terms of sound quality and power output.

    Although the SX 850 fell into this time period, its moderate 65 WPC into 8 Ohms indicated that it was not a contender in the on-going war effort. This, however, could just as well be seen as a plus, because not all monster receivers turned out to be well-equipped for audiophile usage or were in it for the long-haul. In a real-world scenario, 65 honest watts into eight Ohms (and 85 watts into four Ohms) were perfectly capable of driving most conventional 2-way or 3-way speakers on the market. And, while the Receiver Wars did go on to produce true monsters capable of powering even electrostatic speakers and other unruly designs, the SX 850 was most fitting for dynamic speakers of medium to high sensitivity from 4-8 Ohms.

    The specimen shown here had been restored to its original splendour in the weeks prior to our listening tests. Its switches had been cleaned in an ultrasound bath, the capacitors had been checked and replaced where necessary. The relays had been cleaned, and the offset calibrated according to factory standard. The original lamps (that were prone to failing) had been replaced with longer lasting LED lights. The real-wood case had been freed from scratches and re-polished to its original shine. To improve connectivity, an IEC socket had been installed that replaced the original US cord, and four banana/spade terminals had been added in position of speaker output “A”. The SX 850 had been restored to better than NOS condition. Its look and feel made it seem as if no time had passed since 1976.

    The SX 850’s impressive width and weight would have served to give it a noticeably prominent position on any Hi-Fi rack or piece of furniture. And working on the buttons and switches felt more like operating the control panel of a submarine than those of a common household radio. In fact, I was so surprised by the Pioneer’s weight and haptics that I felt compelled to open the unit in order to see where this impression originated from. However, in my explorations I could neither confirm the large transformer nor the wooden casing or chassis to be the sole cause of its weight and solid feel. It was rather the sum of all quality choices that in the end led to this unit’s close to 20 kilograms of weight and its superb rigidity. The 850 was seven impressive kilos heavier than even the twin-powered Harman Kardon 730.

    Recently refurbished units often had a tendency of sounding a bit stale until the new components had been sufficiently run-in to become part of the greater scheme. And it was difficult for me to say in which phase of the running-in process our specimen really was and how much of my sonic impression was affected by this condition. However, having been present during the break-in of many devices, I felt sufficiently knowledgeable to identify areas of potential. If some units will feel a bit light-footed and short-winded during the first couple of weeks, this particular receiver greeted me with a huge sound stage spanning from far left to far right, a solid and dependable center image, and a thick and musky sound. It was as if it was painting with a broad brush.

    Even coming from our Restek V1 and Becker ST-200 separates, I could not help but be drawn in by the SX 850’s colourful and engaging sound. Similar to the Becker, the Pioneer was more about the sensation of listening to musicians playing their instruments live than it was about being present in the highly accurate mastering room of a recording studio, especially during passages of instrumental Jazz. Brushes sounded convincingly metallic and still had a pleasant softness about them. I enjoyed this quality a lot on Tony Bennett & Diana Krall’s album “Love is here to stay”. Similarly, both nylon and steel guitars had a natural timbre with a pleasantly soft top-end, as I experienced listening to José González album “Local Valley”.

    The SX 850 certainly understood about music and, in connection with our silver solid core interconnects and Belden speaker wires, offered the stomping and airy bass presence of a live venue. While bass was perhaps not nuanced, multi-layered, or controlled, I personally preferred this type of 'musical' bass to the sterile impression left by some more recent amp designs with damping factors well above 200. In its current state, the Pioneer was perfectly suitable for extended listening sessions, even for listeners who have high expectations regarding their choice of audio entertainment.

    Both male and female vocals sounded lush and full-bodied with an aura of slight restraint. There was just not as much air and space around the singers as I was used to from our Restek & Becker combination. When it came to vocals, I could not shake the feeling that I was sitting in a recording studio. This is not to say that there was anything unpleasant in the way vocals were depicted, they simply sounded less live and had less of a physical aura than (strangely enough) the instruments did. It seems that the mid-band was not able to breathe as freely (yet) as some of the higher and lower spectrum. This may have been a result of the still ongoing running-in phase, but it could also have been caused by the unit's design. In the end it does not matter too much, because, if we consider that my benchmark was my favoured combination of separate audiophile units, the SX 850 already put up a formidable performance.

    For audiophiles in search of a classic solution for their second or third system who do not shy away from the cost of a (by now necessary) refurbishment, Pioneer sure has some worthwhile receivers from the Golden Age to consider. And the SX 850 was certainly a specimen that I could personally grow attached to. Its colourful and engaging sound, its superb musicality and impressive stage width made it an endearing companion for long and joyful audio sessions any day. Equipped with two MM phono inputs with excellent RIAA correction, two tape monitors, a microphone input and headphone output jack, it is well suitable for most applications. It even features a very convenient -20dB muting switch by which the volume dial can be adjusted to accomodate high input devices, high sensitivity speakers, or both.

    Pioneer Company History

    The world famous electronics company was founded by the Japanese inventor and entrepreneur Nozomu Matsumoto. Born in 1905, the son of a Kobe missionary family showed an early interest in electronics and was among the first to recognise the potential of recorded music in the context of addressing people’s emotions and felt that this could aid the promotion of the Christian faith.

    Therefore, in 1936, he started what was to be the precursor to Pioneer, the “Fukui Denki Shokai Seisakusho”, which translates into the “Gospel Electric Works” in English. His small company took up operations in his hometown Osaka and specialised in the research and development of dynamic loudspeakers.

    Matsumoto’s inspiration had come from western companies that still held the lead in entertainment electronics and shipped them over to Japan. However, Matsumoto had a vision of making this a Japanese technology and, in 1937, his early experiments came to fruition with the introduction of the A-8. It was the company’s first large series speaker driver and Matsumoto referred to it as the “Pioneer”. This speaker was the first to feature the ‘omega sign and tuning fork’ that were later to become the company’s trademark.

    In 1938, Fukui Denki Shokai Seisakusho moved its operations from Osaka to Tokyo where the growing family business specialised in the construction and repair of loudspeakers. Nozomu Matsumoto made sure to involve his family in the operations and was fully supported in this by his wife Chiyo and his two sons Seiya and Kanya. Following his university studies, Seiya took over Marketing and Sales and went on to become the president of Pioneer in 1982.

    The company with the long and difficult Japanese name changed its brand to “Pioneer” in 1962 in an effort to create stronger international brand awareness and went on to become one of the world’s leading developers of first audio and later also video equipment. Pioneer made major contributions in the research and development of loudspeakers, was the driving force behind the development of the laser disk, and next to Sony and Marantz, was one of the first companies to manufacture CD players.

    Pioneer stayed true to Matsumoto’s initial mission statement which had been to develop and manufacture audio products that would speak to and captivate people’s emotions. Perhaps it was this deep focus on the true essence of listening that has earned the company a loyal base of followers until this day.


    • Type: Post WWII AM/FM receiver
    • Tuning range: FM, MW, AM
    • Power output into 8 Ohms: 65 WPC
    • Power output into 4 Ohms: 85 WPC
    • Frequency response: 10 Hz to 50.000 Hz (+0 dB, -1 dB)
    • Total harmonic distortion: 0.1% @ 8 Ohms
    • Damping factor: 25
    • 2 Phono inputs: 2.5 mV, 50 kOhms (MM)
    • Input sensitivity: 150mV, 100 kOhms (line)
    • Microphone sensitivity: 6.5mV
    • Signal to noise ratio: 70dB (MM), 90dB (line)
    • Signal output: 150mV (line), 30mV (DIN), 1V (Pre out)
    • Bass control (100 Hz):  ±10 dB
    • Treble control (10 kHz):  ±10 dB
    • Speaker load impedance: 4 Ohms (minimum)
    • Semiconductors: 3 x FET, 3 x IC, 56 x transistors, 36 x diodes
    • Dimensions: (W) 52.7 cm x (H) 17.3 cm x (D) 41.15 cm
    • Weight: 19.1 kg
    • Accessories: FM T-type antenna
    • Country of manufacture: Japan
    • Year(s): 1976

    Digitising Records
  • 26. Does vinyl sound better than digital sources?

    26. Does vinyl sound better than digital sources?


    Author: Karsten Hein

    Category: High Fidelity

    The beginning of the 21st century saw an ever-increasing presence of compact and convenient digital technology in our households. Ever since the invention of the iPod, we have been able to fit an infinite amount of songs in our pockets. And streaming services such as Spotify, Tidal, and AmazonMusic, to name just a few, have provided universal access to a sheer endless selection of music at affordable prices.

    While some people enjoyed the ability to scroll through an abundant list of choices without having to make a personal commitment, others were feeling lost and started missing the mutual aspect of the relationship, the connection between a band and its fans, that music once was. It may have been a natural impulse for these people to start being nostalgic about the pre-digital age, in which musicians and record labels could manage to make a living with relative ease and where the incentive was high to continuously create lots of quality content, rather than churning out 1-hit wonders based on click-bait algorithms and predominantly similar-sounding tracks.

    Vinyl was a welcome refuge to those fleeing the effects of the digital madness. In fact, records stood for everything that streaming music did not: The medium was naturally limited in the number of songs that fit on each disc. During the reading of each track, the stylus followed a signal grove that contained a faithful analogue transcript of the acoustic event. Pauses between songs were visible as recurring patterns to the naked eye. To play a song or album, one had to physically get up from the sofa and choose one record from the available collection. And, in order to have quality music available, one had to become a discerning collector and strategically develop one’s taste in music.

    Putting the needle on the record produced a crackling sound even before playing the first song, and it was possible to visually follow, appreciate, and comprehend the process. Turntables are transparent about their method of reproducing music. Unlike most digital equipment, where the music reproduction comes from an invisible and practically unchangeable black box, turntables have a personal character and will perform better with increasing know-how of the person setting them up. Choosing components, understanding the mechanics, eliminating vibrations, managing the electrics, and improving the electronics — all these factors contribute to the quality of sound. Turntables practically invite their owners to care deeply and to begin a journey of exploration.

    Turntables that have been set up with proper care will sound very similar to CDs and other high quality sources, such as online streaming devices. They will not match the CD’s low noise floor, nor will they offer the dynamics available from modern digital formats. They will, however, produce a sound signature that is highly harmonious as well as a softer and more natural top-end that some listeners find to be more pleasant to the ears. Despite their intrinsically lower specifications, the technical abilities of turntables are perfectly sufficient for joyful listening sessions. Records that have been well-maintained will not produce lots of noise, either. Clicks and pops are rare and in any case secondary to the music signal. It is an urban legend that vinyl heads enjoy listening to record noise. If at all, they enjoy that last bit of unpredictability that the record has maintained.

    Turntable sound quality is mostly compromised by poorly pressed or mastered records. In my own experience, modern vinyl productions often cause problems, because the mastering engineer did not understand the medium well enough. This often leads to sibilance or other distortion. With the growing demand for analog recordings and only few experienced factories available, the quality of pressings can be pretty dismal. Discs arrive warped, out of centre, or poorly moulded. 180 grams records are no guarantee that the quality is better. While records produced during the 70s mostly offered excellent durability and quality, modern productions sometimes seem to use lower grade materials and production methods, causing 50-70% of all modern records to be of less than ideal quality. In this context, it seems unfair that media sellers will refuse to take records back, even if the pressing is of a low standard.

    Setting up a turntable to play music well is an art form comparable to fly-fishing. While it is surely cheaper and more effective to purchase fish from the deep freezer of a local supermarket, the sensation of accomplishment and the joy of consumption cannot be compared. Of the analog sources ranging from reel-to-reel via 8-tracks to compact cassettes, etc. only the turntable offers the optimum combination of longevity, convenience, and sound quality. And, while it certainly does not sound ‘better’ than digital sources, it will sound different from machine to machine and from owner to owner, thereby adding an exciting personal dimension to the otherwise arbitrary and perhaps even boring experience of canned music reproduction. Sophisticated turntable setups often say as much about their owners as they do about the quality of music.

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