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.

  • Jamie Saft, Loneliness Road

    Jamie Saft, Loneliness Road


    Author: Karsten Hein

    Category: Audiophile Music

    Tag(s): Jazz

    For his 2017 album "Loneliness Road”, Jamie Saft teamed up with bassist and composer Steve Swallow, drummer and composer Bobby Previte, and singer-songwriter Iggy Pop, to arrange a unique and, in many ways, unexpected combination of talents. The challenge was to merge the distinct musical personas of the three artists into one cohesive work of art. While the concept seemed intriguing to me at first, I quickly found that the style and mood of the vocal tracks are noticeably disjunct from the instrumental passages, which only serves to highlight the more general lack of cohesion that the album suffers from.

    While many of the tracks of “Loneliness Road” may work quite well on their own, I would have preferred to see a build-up of suspense to a climax that spans more than a single song. I guess, I would have expected the fusion of Iggy Pop's raw and energetic rock with Saft and Swallow's Jazz expertise to make for some really interesting dynamics. However, the execution often feels forced and uneasy. The transitions between the different genres and musical styles are simply too abrupt and awkward, leaving me with a sense of disconnection from the overall composition of the album.

    Another notable issue is the inconsistency in the vocal performances by Iggy Pop. While his distinctive voice has been a defining element of his career, I find that it does not blend all too well with the Jazz-infused instrumentals provided by Saft and Swallow. Iggy Pop's vocals often come across as out-of-place and strained, lacking the necessary nuance and subtlety that is required to navigate the Jazz landscape effectively. This mismatch between vocal delivery and musical arrangement further adds to the disjointed nature of the album.

    That said, there are some redeeming qualities to be found on the album. The instrumental performances by Jamie Saft and Steve Swallow serve well to showcase their musical proficiency and creative abilities. Their interplay and improvisational moments offer glimpses of masterful synergy that I would have preferred to see throughout the album. 

    Additionally, some of the lyrical content on "Loneliness Road" displays flashes of poetic introspection and emotional depth. Iggy Pop's lyrics, although sometimes overshadowed by the mismatched vocal delivery, touch upon themes of longing, isolation, and the human condition. In moments where the lyrics are given space to breathe and take center stage, they provide a glimpse of the album's potential to connect on a deeper emotional level.

    Some critics have suggested that the production quality of “Loneliness Road” was not on par with similar Jazz productions and could seem muddy and congested, which made it challenging for some listeners to discern individual instruments and appreciate their contributions fully. While this may or may not be true for the vinyl record, it is a trait that I have not been able to detect or reproduce on our HiFi systems when working with the album on CD. In fact, the excellent recording quality and mastering is the very reason for me to include the album in my list of audiophile choices. Instruments appear live and life-like with lots of space around them, making this a decent CD album to pull out of the shelf when it comes to the task of representing natural instruments and vocal timbre.

    From an audiophile perspective, I would have preferred the piano to be positioned centre stage, as is mostly the case with music recordings these days. "Loneliness Road” instead places Steve Swallow’s drum set at the centre of the stage with the piano being positioned far off to the right hand side. This placement gives Swallow’s performance as a drummer lots of attention, but it also requires the listener to tolerate long passages during which the harmonic weight of the music appears off-centre. In the very beginning, I found myself repeatedly checking speaker position and balance to confirm that the fault was not caused by some accidental flaw in my HiFi setup.

    In conclusion, I must confess—to those who have not detected this already—that I have a love-hate relationship with this particular Jazz album. I pull it out whenever I am tired of the ordinary, smooth, and predictable, and when I am in the mood for the unconventional and unexpected, the raw and the unfinished. On such days, I tend not to mind the slight irritation from the off-centre placement of the piano or the lack of cohesion among the songs. Occasionally, I enjoy the feeling of being teased and of not getting exactly what I want, especially, when the people who are teasing me are music professionals at such an advanced level of the game.

    Jörg Hegemann
  • 2. Imaging

    2. Imaging


    Author: Karsten Hein

    Category: High Fidelity

    Imaging describes the ability of a specific HiFi stereo system or a headphone setup to accurately localise individual sounds within the soundstage. Good imaging provides a clear and precise placement of instruments and vocals. For audiophile listeners, it is often a phenomenon that fellow human beings can readily tell when a visual image is warped, distroted, cluttered, or hazy, yet are completely oblivious to the same characteristics in sound. The following expressions are used to describe imaging:

    Describes the ability of an audio system to precisely locate and position individual sound sources in the stereo field.

    Refers to the ability of an audio system to present different instruments or voices at different depths within the soundstage, creating a sense of depth and dimension.

    Sonic separation
    Describes the degree to which individual sound elements are distinct and well-defined within the audio presentation, allowing for easy differentiation and identification.

    Describes the ability of an audio system to reveal subtle nuances and intricacies within the music, allowing for a greater level of insight and engagement.

    Refers to the accuracy and precision with which sound sources are positioned within the stereo image, resulting in a highly defined and realistic soundstage.

    Instrument separation
    Describes the degree to which different instruments are presented as distinct entities within the soundstage, allowing for easy identification and tracking of individual instrument lines.

    Ambience retrieval
    Refers to the ability of an audio system to accurately reproduce the acoustic space and ambiance of a recording, providing a sense of the original recording environment.

    The expressions used to describe Soundstage and Imaging can overlap to some extent. Refer to my discussion of Soundstage for further vocabualry to describe music presentation.

    crossXculture Business Language Training
  • Boris Blank and Malia, Convergence

    Boris Blank and Malia, Convergence


    Author: Karsten Hein

    Category: Music & Talk

    Tag(s): Jazz

    In 2014, Boris Blank, the enigmatic musical genius and founding member of the influential Swiss electronic duo Yello, returned with his solo project, "Convergence." Known for his distinctive soundscapes and experimental approach to music, Blank's new album promised to be a captivating journey for audiophiles and electronic music enthusiasts alike. Vocals were recorded with the Malawian singer-songwriter Malia. However, while "Convergence" offered glimpses of brilliance, it also stumbled in some areas, making for an intriguing yet flawed listening experience.

    "Convergence" begins with "Prologue," an ambient and ethereal piece that immediately transports the listener into Blank's musically simple but sonically exploratory realm. The sparse instrumentation and haunting melodies create an atmosphere of mystery and anticipation. The attention to sonic detail and meticulous production are commendable, setting a high standard for what is to come. With the second song “Interference," Blank further showcases his knack for crafting intricate sonic textures. The pulsating beats, intertwined with ethereal synth pads, create a hypnotic groove that is hard to resist. However, despite the song's captivating qualities, it lacks a clear sense of direction and fails to fully engage the listener beyond the mere surface.

    "Euphoria" is undoubtedly one of the standout tracks on the album. Here, Blank demonstrates his mastery of sonic layering and manipulation. The lush synthesisers, coupled with intricate percussion and ethereal vocal samples, create a captivating sonic tapestry that envelops the listener. It is a true testament to Blank's ability to create otherworldly soundscapes. While "Fragmented" exhibits some interesting sonic ideas, it falls short in execution. The disjointed nature of the track, although intentional, results in a lack of cohesion that makes it difficult for the listener to fully engage with the music. The experimental elements overshadow the melody and structure, leaving the listener feeling disconnected and disoriented.

    "Resonance" again is a testament to Blank's ability to create immersive sonic experiences. His meticulous attention to detail in the production shines through, as the layers of instrumentation and atmospheric effects interplay with each other seamlessly. However, the track's extended duration feels unnecessary, and it could have benefited from more concise editing to maintain the listener's focus of attention. With "Metamorphosis," Blank ventures into more experimental territory, fusing unconventional sounds and rhythmic patterns. While the track displays a level of technical prowess, it lacks the emotional depth and resonance found in his best work. It feels like an intellectual exercise rather than an organic expression of musicality. The album concludes with "Epilogue," a somber and introspective piece. The delicate piano melodies, accompanied by atmospheric textures, evoke a sense of melancholy and reflection. It serves as a fitting ending, wrapping up the album thematically and leaving the listener with a lasting impression.

    Convergence is a testament to Boris Blank's boundless creativity and mastery of sound manipulation. The album's highlights, such as "Euphoria" and "Resonance," showcase his ability to create mesmerising sonic landscapes. However, the album suffers from occasional missteps, particularly in tracks like "Interference" and "Fragmented," where the experimental nature overshadows the melodic and structural elements. Despite these flaws, "Convergence" remains an intriguing release that will undoubtedly captivate fans of Blank's unique musical vision. 

    Note: In daily practice, I occasionally take this album off the shelf to demonstrate the sonic width of a given HiFi setup, especially when presenting to tech-minded listeners. It also serves well to determine how potent a system is in plying apart individual sonic events and looking beyond the samples. It is not a great album to choose for sonic cohesion as, except for Malia’s vocals, there are not many natural yard sticks that can be applied.

    80s night
  • Echle RR25-16

    Echle RR25-16


    Author: Karsten Hein

    Category: Gear & Review

    Tag(s): Loudspeakers

    Shortly after the turn of the century, some twenty years ago, the audio technician and car-Hifi store owner, Winfried Echle, came across the review of a Dynamic 16cm bass-to-midrange driver with Kevlar diaphragm when leafing through one of the last issues ever printed of the German electronics magazine ‘Funkschau’. The chassis was made in Thailand and, as it turned out, was difficult to obtain from a German supplier. This prompted Winfried to contact the Thai embassy in Frankfurt to establish direct contact with the producer in Thailand. When he finally received a response, it was to inform him that the minimum order quantity was at 100 pieces. Winfried took a deep breath and made the purchase. “I was feeling put under pressure, but what I should have done, would have been to place an order for 200 units instead.” he told me laughingly, “How could I have foreseen how successful these little drivers would become.”

    His first serious bookshelf-size loudspeaker was of a two-way design, with a front-ventilated bass port that was placed in one corner right next to the tweeter. The passive crossover cut the tweeter off at 1,500 Hz and at a 6dB slope per octave. Early models featured a 2.5cm Peerless soft-dome tweeter, which Winfried ended up replacing with a Vifa XT-300/K4 ring radiator on later models. The ring radiator did not play as loud as the soft-dome tweeter, but it introduced a new sweetness to the sound and offered a more pleasant drop-off in the treble. The crossover parts, internal wiring, and wire terminals were of a high quality, and the pass port was fine-tuned to be as linear as possible, preferring tight control to the usual 60 Hz hump. Winfried spent some time listening, measuring, and adjusting the crossover parts and bass port until he was pleased with the result.

    Showing his new prototype speakers to friends and visitors to his shop, some of whom were industry specialists themselves, Winfried received excellent feedback on his design and ended up selling over one hundred of these bookshelf speakers. In fact, he sold more speakers in the given price category than the local HiFi shop did at the same time. To the owner of the HiFi shop, this did not come as much of a surprise, as Winfried’s unique price-performance ratio even impressed his friends at Hessischer Rundfunk who bought two pairs of speakers for proper installation in their broadcast vehicles. But, was this just a lucky punch, or a replicable show of skills? Listening to the story made me curious, and I just had to find out for myself.

    Ever since hearing about his monitor speakers for the first time, I was tempted to take them home with me for a trial run. But it was not until our impending relocation from Frankfurt am Main to Marne, Schleswig-Holstein, and when our weekly meetings in Aschaffenburg were slowly coming to an end, he let me know that he would actually be honoured if I still found the time to write a review. Of course, I did not have to think twice about this and brought along a large Eurobox for transport, into which the pair fit perfectly. On my drive back home, I contemplated which amplifier to test them with and decided that I would go with our Dynavox VR-70 tube amplifier, unless this would prove to be problematic due to some unforseen mismatch in capacitance or resistance.

    I gave our EPI 500 floor-standing speakers a good listen and then set up Echle’s bookshelf speakers in that same position. The DIY stands I used had originally been designed for our KEF iQ series speakers, and they were made of sturdy PDF boards perched on spikes with coasters that were in turn placed on felt cushions for decoupling towards the ground. The finished stands weighed about as much as the speakers themselves and gave them a firm position while preserving their ability to sufficiently free themselves from the floor not to excite ghastly resonances. With the Vifa tweeter being mounted off axis, I was puzzled for a bit whether to have the tweeters on the inside towards the listening position or to rather have them on the outside, away from the listening position with the bass port on the inside. I decided to listen to the set with the tweeters on the inside first.

    The resulting musical image was accurate yet somewhat thin-sounding. The center image was super sharp, and voices seemed slightly thickened and throaty with an alluring touch. There was lots of bass texture, even if low-bass extension was not great. The speakers performed in a well-behaved manner with a sensible top-end. The midrange was insightful and homogenous. Piano keys sounded warm enough but were lacking some of the treble bite and bass punch. On occasion, I noticed a little time-smear and could sense more than the usual sibilance. Looking at my setup, with the vertical radiation axis of the speakers merging about 50cm behind my head, I could see that I had brought the tweeter coils relatively closer to my ears than the woofer coils.

    Since the woofer coils were usually positioned deeper inside the speaker cabinets than the tweeter coils, swapping the left and right speakers to position the treble outward would help to correct this issue by increasing the distance between the tweeter and the ears. The result was less time-smear and sibilance and an increase in stage width. The midrange remained the strong point with accurate tonality. The initial lightness of sound had disappeared. The result was vocal credibility and a kind of no-fuss reporting of musical events. The term understatement came to mind, an impression that was even enhanced by their their ample use of build-depth rather than height or width.

    From Nick Cave’s live-album ‘Idiot Prayer’ I then changed to Boris Blank’s studio album ‘Convergence’. I also turned up the volume from Cave’s natural-sounding voice to moderate disco. Boris Blank has been a long-time favourite among tech-minded people, and on its basis the speakers could show their ability to keep the separate layers of samples apart. I was impressed with the insightful positioning of bass-events from left to right and from top to bottom as well as the lack of tweeter aggressiveness I would normally have expected from smallish speakers playing loud music. I did notice, however, that the higher excursion of the woofer of +/- 8mm did lead to to a certain breathiness in the treble. I am not convinced that the Doppler effect would have been as pronounced if the bass port had not also been positioned between the tweeter and the listening position.

    I enjoyed listening to these speakers being played loud, especially because their treble was a little more forgiving than on our other models. Michael Patrick Kelly’s live album “ID” came to mind, and the speakers did not disappoint in terms of speed, agility, and, to some extent, even dynamics. The kick drum sounded hard and firm. These loudspeakers would work equally well playing Rock music and Jazz, and that combination was not all too common. Rock music requires for the music to be kept together rather than taken apart, and this was certainly the case.

    To round off my exploration, I put on some Norah Jones. “Feels like home” was presented with musky vocals and amber keyboard notes. It sounded at once exciting and spacious as well as refined and well-proportioned. The soft top end that had served so well when playing the speakers louder here resulted in a slight lack of crispness in piano notes. In the end it seemed as though we cannot have it all, or at least not in the still affordable price categories. I wonder, how many of us would get up to tweak the sound coming from a real live event, if we were given the power to do so. As around speakers and for serious listening Winfried’s speakers were certainly able and enjoyable tools. When it came to mixing music and discerning listening, on the other hand, the somewhat relaxed treble presentation might make problems in this area seem less dramatic than they really were. For monitoring vocals, these speaker were truly excellent.


    • Type: 2-way bookshelf speaker
    • Speaker principle: vented cabinet
    • Crossover 1,500 Hz (@6dB per octave)
    • Application: entertainment, monitoring
    • Tweeter: 25mm Vifa XT-300/K4 (Tymphany)
    • Tweeter principle: ring radiator
    • Bass driver: 16cm dynamic, Kevlar diaphragm 
    • Dimensions: (H) 320mm, (D) 350mm, (W) 210mm
    • Country of manufacture: Germany
    • Designer: Winfried Echle
    • Year: 2002

    Digitising Records
  • 1. Soundstage

    1. Soundstage


    Author: Karsten Hein

    Category: High Fidelity

    Soundstage refers to the spatial representation of sound in an audio recording. It encompasses the width, depth, and height of the sound image. A good soundstage creates a sense of space and allows for precise localisation of instruments and vocals.

    Refers to a soundstage that extends far beyond the boundaries of the speakers, creating a spacious and expansive listening experience.

    Describes a soundstage that is tightly focused between the speakers, lacking width and breadth.

    Indicates a soundstage with significant depth, where the placement of instruments and vocals can be perceived as being in multiple layers reaching far behind the speakers.

    Opposite of deep, a shallow soundstage lacks depth dimension, giving the impression that the audio is closer to the listener and without also creating a sense of distance.

    Describes a soundstage that offers a realistic and immersive listening experience, where the placement of instruments and vocals can be perceived in three dimensions: width, height, and depth.

    Refers to a soundstage that lacks depth and height, giving the impression that the audio is positioned on a single plane between the speakers.

    Indicates a soundstage where the audio appears to be projected more towards the listener, creating a sense of intimacy and immediacy.

    Opposite of forward, a recessed soundstage gives the impression that the audio is positioned further away from the listener, creating a sense of distance and spaciousness.

    Describes a soundstage that exhibits exceptional imaging and precise placement of instruments and vocals, creating a lifelike and hologram-like listening experience.

    Indicates a soundstage where individual instruments and vocals are well-defined and distinct, without electronic haze or unrealistic time-delay, allowing for precise localisation within the audio image.

    Refers to a soundstage where the audio lacks precise localisation, with instruments and vocals appearing unnaturally spread out or blended together.

    Describes a soundstage where instruments and vocals can be perceived as occupying different layers or planes within the audio image, adding depth and separation.

    Indicates a soundstage where the various elements of the audio image are well-integrated, resulting in a seamless and unified presentation.

    Refers to a soundstage that feels crowded or dense, with a lack of separation between instruments and vocals, leading to a muddled or cluttered listening experience.

    Describes a soundstage with a sense of openness and space, where the audio seems to breathe and have room to expand.

    Indicates a soundstage that creates a close and personal listening experience, with instruments and vocals appearing to be in close proximity to the listener. Often, this is also associated with a warm midrange sound.

    Refers to a soundstage that is incredibly large and expansive, giving the impression of a sheer endless sonic landscape.

    Indicates a soundstage where the placement and distribution of instruments and vocals feel evenly spread and well-balanced, creating a sense of harmony and coherence.

    Describes a soundstage that captivates and draws the listener into the music, creating an engaging and immersive listening experience.

  • Let's explore together

    Let's explore together

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    If you happen to live in the greater Frankfurt / Rhine-Main area and own vintage Hi-Fi Stereo classics waiting to be explored and written about, I would be honoured to hear from you!

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    Audiophile greetings,