Many high-end audio brands may have many models, different grades of front and rear amplifiers or speaker models, but perhaps you have also found that they often only have a cartridge amplifier, so that players who like this brand have no choice, but if the level of player demand is different, maybe you can only choose someone else. The author suspects that the reason may be that the owners of this part of the brand are not specialized in the field of vinyl, or they may not pay much attention to this market.
In fact, for the vinyl system, there is no doubt that the phono is a very important part, we all know that the signal level output by the cartridge is very low, MM dynamic cartridge in mV millivolts, MC dynamic cartridge in 0.x mV. 1mV is 1/1000V (volts), such a low-level signal needs to go through a high-magnification amplification line to cross the input sensitivity of the conventional pre-stage, and this process also needs to make accurate RIAA equalization, and maintain a very high signal-to-noise ratio, which can be very high for the design of the line, the general designer may know that the op amp can solve the problem more simply, but this is equivalent to getting good sound? Obviously, it is not so simple, the record and amp line from the power supply, the RIAA equalization line, as well as the high-gain amplification stage, and even the shielding and shock absorption of the chassis, every link is quite exquisite. To use a metaphor, a ten-dollar electronic watch can also be timed, so what is the difference between it and a mechanical watch of tens of thousands or even hundreds of thousands? Usable and extremely exquisite, not at all on one level.
Obviously, Mr. Volker Bohlmeier, who has experienced the golden age of analog recording and is a professional sound engineer, his understanding of vinyl replay is much higher than that of ordinary sound designers, and he set the goal of being as close as possible to the original sound of the scene, so that the vinyl sound “comes alive”, rather than simply pursuing the sound effect, which is confirmed by the Einstein Einstein brand he founded. Because Einstein has and is now a large number of cartridge models, it is rare in the audio circle, and the products range from Hi-Fi entry level to Hi-End level, and only a handful of professional vinyl product brands in the market can match it.
Einstein’s past and current record and amp models include: The Little Big Phono, which provides 68dB (2500x) gain and only 0.18% total harmonic distortion in a small size; The Turntable’s Choice also has a gain of 68dB (2500x), a total harmonic distortion of less than 0.03%, and an output voltage of up to 10V, which is already a very ideal specification; The flagship split design The Phonoamp, completely physically isolates the power supply and audio lines, thereby minimizing the interference of vibration and electromagnetic waves, with a gain of up to 72dB, which can be adapted to most low-output MC cartridges, with a signal-to-noise ratio of 82dB, and the advantages of the split power supply design, the distortion rate is less than 0.04%, which is perfect from every aspect; The Phonostage, the protagonist of this article, adopts an integrated design with built-in power supply, which can actually be regarded as an integrated version of the flagship split The Phonoamp, with a gain of 68dB (2500 times), a signal-to-noise ratio of 80dB, an output voltage of 7V, and a distortion rate of less than 0.05%, which is also good but has a higher cost performance. Do you know? The Phonostage is priced at about a third of the flagship’s.
The Phonostage’s exterior design is actually no different from the flagship The Phonoamp’s main unit, with mirrored stainless steel bent panels and top covers, and a black acrylic panel mounted on the panel, simple but noble. There is only a blue LED power indicator in the middle of the panel, but after turning on, there is a light shining downward under the panel, and the atmosphere is quite romantic. Turning to the back of the machine, The Phonoamp provides one set of RCA input and one output terminal, and the grounding terminal is designed with a large design, which is very comfortable to handle. In addition, the load terminal at the bottom is not used to connect signals, but for input impedance matching adjustment. How to adjust it? Unlike the common way of matching lines in the machine with piano switches, Einstein’s research showed that such switches would cause additional signal loss, so they creatively reserved a set of RCA terminals and adjusted the impedance load at the phono input by building a high-precision resistor into the RCA plug. At the same time, Einstein equipped The Phonostage with two pairs of matching resistor accessories, 100 ohms and 300 ohms, which players can choose according to the characteristics of the cartridge.
Opening the top panel of the chassis, it can be seen that although The Phonostage is an integrated design of built-in power supply, it is also optimized in a targeted layout to avoid interference as much as possible. For example, the toroidal power transformer and the audio line are placed at opposite angles in the machine, and the transformer is wrapped with a shielding cover to reduce magnetic leakage and impact. This is not enough, including the transformer and the power line, are mounted on a separate overhead floor, and the vibration interference is further isolated by means of damping pads on the overhead struts. The signal lines with completely independent left and right channels are installed erectly on the backplane, and are also isolated by metal partitions. Therefore, although The Phonostage is a one-piece design, in fact, the interior is very elaborate isolation shielding, and the effect of split design is pursued as much as possible.
The choice of core technology and materials is, of course, the focus of the album, and The Phonostage maintains the highest standards of the factory. The power input socket uses a filter socket from Schutte to avoid power noise entering the machine; The toroidal power transformer does not blindly pursue high power, and the selected 20VA capacity ensures sufficient power supply while avoiding more vibration and magnetic leakage interference. The design of the power circuit board is very spectacular, in addition to the use of symmetrical independent lines of the left and right channels, great attention is paid to the stability and purity of voltage, so up to 18 35V2200μF electrolytic capacitors composed of “large pond” as power filter, multi-stage voltage regulator tube is dissipated by a large area of heat sink to ensure long-term stable work.
The two fully independent audio lines are designed with the shortest signal path concept, so all inputs, outputs and Load terminals are soldered directly to the board. The key RIAA equalization line adopts a combination of high frequency passive and mid frequency active. The signal amplification stage uses a combination of selected transistors and OPA op amps, and the performance characteristics of the two channel circuit boards are strictly tested and paired to control the error within 0.3dB, so as to obtain excellent sound field and image positioning effect.
RIAA is an abbreviation for Recording Industry Association of America, and the RIAA equilibrium curve is a quantitative specification for vinyl records developed by the Recording Industry Association. The reason for this standard is that if the entire frequency band is engraved with a completely linear amplitude when the LP record master is engraved, the engraving groove will change very much, the higher the frequency of the signal texture is shallower and narrower, the lower frequency the signal is deeper and wider, which will not only make the stylus difficult to trace, but also greatly reduce the capacity time, and even make it impossible to record ultra-low frequencies (such as early 78-rpm records). Therefore, the RIAA developed a frequency equalization curve standard, and when making records, the curve of greatly attenuating low frequencies and increasing high frequencies was used to make plates, so that the record could contain more content; When replaying, the opposite curve is used to restore the correct balance. Since the RIAA equalization circuit attenuates the high frequencies during playback, the high-frequency noise floor of the record is also attenuated at the same time, resulting in a higher signal-to-noise ratio. Then, the accuracy of this reduction curve is the lifeblood of singing and amplification.
After years of technical exploration, there are several popular RIAA reduction curve line technologies, such as active filters (negative feedback types), passive filters (CR types), hybrid filters (both CR and negative feedback types), and LCR filters. Obviously, The Phonostage uses a hybrid filter that combines CR and negative feedback types. The CR type passive filter is used for high-frequency reduction, filtering the frequency through a complex capacitor-resistor network by varying the amount of attenuation at different frequencies to comply with the RIAA specification. This technique does not cause voltage overload, because there is no feedback, it can achieve purer sound quality reproduction than other types, and the RIAA compensation is more accurate. To solve the problem of not providing gain, Einstein solved the impedance matching problem with optional Load optional external resistors. For the replay of low and medium frequencies, negative feedback type active filters are used, and different amounts of negative feedback are applied, with deeper feedback to high frequencies and shallow feedback to low frequencies, thereby improving the signal-to-noise ratio and stability.
Listen to The Phonostage singing and amplification, the best match is of course Einstein’s The Pic Up high-output cartridge with the same price (39,800 yuan), with an output voltage of 0.4mV, which is undoubtedly a Tian Xian match. However, due to the limited conditions, this audition is paired with the flagship Ethos from the British Goldring, this MC cartridge internal resistance 4 ohms, output level 0.5mV±1dB, the factory’s recommended load impedance is 100Ω, which is also consistent with the effect of comparing the experience of Load during audition, the most balanced sound when using 100Ω, the fineness and low-frequency clarity are better than 300Ω. In addition, it may be the use of full transistor design, coupled with the chassis is relatively large, the reason for better heat dissipation, The Phonostage even if it is powered on for a long time, 7×24 hours without turning off is only a slightly warm state, so you can safely turn on the long cooker and always keep it in the best working condition.
The focus is, of course, on sound performance, and the first impression of The Phonostage is that the overall balance, sound quality purity and detail analysis are all very good. For example, listening to Emil Gilels Emil Gilles Emile Gilliers’ “Beethoven Piano Sonata”, in which the slow movement of “Pathétic” is a “song like a song”, although the tune is sad and melancholy, but it is so calm and calm. The Phonostage presents an intoxicating effect, although the performance is a bit slow, but this is more testing the details of the audio equipment, air sense and micro-dynamics and other aspects of the quality, in the past heard some singing and playing this sound is not very active, but this time The Phonostage will not have this situation. The piano statement is bright and there is no shortage of subtle “expressions” of the performer’s fingers gently undulating, and the musical form, although relatively restrained, is completely in line with the style of DG recording. Especially in the replay of “Moonlight”, The Phonostage vividly expresses the glorious interpretation, the poetry, tranquility and sadness in the music, as well as the changes of relaxation, superb piano skills, majestic and powerful performance, the perfect touch effect brought by the powerful performance are accurately presented. Listening to this interpretation, perhaps I have a deeper understanding of Beethoven’s world.
Another example is listening to Ruiming Records’ “Moon in the Deserted City”, which uses special instruments such as shakuhachi, lute, shamisen, and taiko to interpret music that spans thousands of years of time and space, and completes the recording in Japan. The Phonostage is characterized by rich detail and good sense of space, especially the sense of breath and plucked strings of these instruments, and the rich analog sound makes the sound quite vivid, and the soft, delicate sound quality is reverie. There is also a taiko effect in this record to test the performance of dynamics and low-frequency speed, you have not heard it with your own ears, you may not believe that the low frequency of the vinyl system is much better than the same level of CD players, especially The Phonostage’s low frequency has quality and quantity, clear and powerful low-frequency transient response is fast without dragging, and even shows the strength and ruthlessness of the drumstick’s hitting the drum skin, and the exact position of the taiko drum in the recording space, which is as shocking as ever. It can be seen that The Phonostage’s low-frequency performance is very good. I have heard of many vinyl systems in the past, either weak in dynamics or bursting with blurred lines, and the contrast is superior.
In addition, listening to string orchestras with The Phonostage is also desirable, such as replaying the DG version of Karajan’s Dvořák Cello Concerto with the Berliner Philharmoniker, with Rostopovich for solo cello. The conductor, soloist and orchestra are all top performers. Recorded in 1969, the concerto is melody with ease, and the sound quality is typical of Einstein. Karajan’s conductor is authoritative and full of tension, spreading out the momentum and scene of the music, while the cello under Rostopović’s bow is balanced and graceful, and the melody is exciting. Hearing this, it is already difficult to analyze and describe from the perspective of high, medium and low frequency performance, this kind of overall sense of strength, music emotional rich sound characteristics, it is easy to forget the task of auditioning the sound, the heart has followed the ups and downs of the music floating “outside the nine clouds”.