It is an audio manufacturer that we handle. The sound of both amplifiers is well-established and a popular manufacturer.
Each has a different appearance, and has its own characteristics from the chassis construction to the internal circuitry. The sound that is played back also has the characteristics of each manufacturer, so this time I would like to talk about the characteristics of each manufacturer and the differences in sound from a personal perspective.
Bakun Products
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https://www.exclusive-audio.jp/shop/products/list.php?category_id=17
It is the only manufacturer listed here that does not use vacuum tubes. It is an audio manufacturer headquartered in Kumamoto, which has recently been acclaimed by audio magazines such as MJ. In addition to home audio, we also make amplifiers and microphones for professional use.
The feature is Bakun Products' proprietary SATRI circuit. There is almost no distortion (EX specification 0.05% / UL specification 0.007%), enabling ultra-high-precision amplification.
SATRI-IC, which was created with the aim of faithfully reproducing recorded sound sources, enables ultra-high-precision amplification with almost no distortion (distortion rate 0.05%~0.007%). Under the leadership of genius developer Nagai, the series has now evolved to the fourth generation. From the MK4 series, a newly developed HIBIKI circuit has been added to achieve even higher definition and higher precision sound. The cloudless transparency of a single point from the high frequency range to the low frequency range stands out due to the high SN and the very quiet background. Since it is sharp and has clear outlines, it conveys the delicate and faint background sound that may or may not be heard, and the slight lip movement of the emotional vocals. The reproduced sound, which has no color or decoration at all, and no emphasis on high and low frequencies, reproduces the atmosphere and scene of the recording site as it is. However, since it is faithful to the sound source, owners who focus on low frequencies such as deep bass may want a little more low frequencies.
And speaking of Bakun Products, it is a SATRI-LINK connection that uses a current output that sets it apart from other companies along with the SATRI circuit. By connecting Bakun devices via SATRI-LINK, it is possible to carry music signals with a much larger amount of information due to a large current of direct current, with almost no noise than the normal connection method (voltage connection). The overwhelming amount of information that is not missing and the music signal with almost no distortion or noise coupled with the SATRI circuit is the true essence of the Bakun sound.
On the other hand, it has a high affinity and can be combined with other companies' amplifiers without difficulty. If the tube amplifier is not the CAP series, there is a lot of pocket that you can enjoy without killing the characteristics of the tube amplifier you use.
The appearance is a matter of preference. The contrast between the orange logo and knobs on the black body is actually the same color scheme as the majority of speakers and wooden racks, etc., and has a high affinity and blends in comfortably.
The orange knob is made of a high-grade material called Bakelite. The chassis is made of aluminum. The reason is that the sound is distorted with iron, and to avoid that, copper is used or shielded with another material is heavy and costly, so we do not use it. In addition, aluminum is lightweight and contributes to compactness, so it may be a big advantage that there is no difficulty in installation. The transformer uses an R-core or toroidal core with low leakage flux, so the influence of magnetism is not a level to worry about. Also, the speakers are not a problem. However, since the magnetic force of the drive system used by the player is strong, it is safer to keep a slight distance, or if installing them in a stack, it is safer to leave a little distance by leaving one unit in between, such as with a preamplifier in between.
Astro Electronics Planning
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https://www.exclusive-audio.jp/shop/products/list.php?category_id=18
It is a manufacturer of audio equipment centered on tube amplifiers, which has been highly praised by Audio Magazine for its robust chassis construction and sound.
The feature of Astro Electronics is the construction of a robust chassis. The high-end model is made of 2 mm or 3 mm thick bent stainless steel (duralumin for medium-sized models), and it is a high grade with a higher purity than the one used in stainless steel cutlery, which is quite expensive, and the touch of the hand is slightly higher than that of familiar tableware. This chassis alone weighs a lot. The inside is further reinforced with stainless steel or oxygen-free copper. The mirrored exterior with almost no seams or rivets is solid and cold, but it shows a high degree of perfection. The reflection of the gentle light of the vacuum tube under the warm light gives it a very atmospheric appearance.
In common with all models, the front panel is made of an extra-thick aluminum plate of 10 mm to reinforce the tightening of the entire chassis and to design Astro Electronic Products. The heavy, gutsy chassis that Bakun Products did not choose has been selected to shut out vibrations and noise. In addition, the vacuum tube mounting port has a double structure with heat dissipation and vibration countermeasures. The power amplifier has an independent volume on the left and right, so it is useful for a little balancing, and it is possible to listen to music other than records without a preamplifier.
The transformers are made mainly by Hashimoto Electric and are custom-made products specified by Astro Electronics, and the capacitors and volumes are all carefully selected and assembled by hand wiring. Almost all the assembly work is done by one veteran amplifier craftsman, so the materials used are different, but the quality of the product is the same regardless of the price, so the low-priced model may be quite a bargain. The sound created from a well-thought-out and well-crafted chassis, excellent transformers, and high-capacity condensers is not as warm and soft as the image of a tube amp. The sound is crystal clear and bright. The sound image is solid and three-dimensional, and the mid and low frequencies are rich and generous. The mid-to-high-end preamps further enhance the extension of the high frequencies, clear contours, and rich musical expression throughout the entire range. Basically, it is faithful to the original sound source, so the sharp and uncolored sound may seem clear and cool for a tube amp, but it reproduces the sound source clearly, powerfully, and expressively in detail.
Astro Electronics prefers to use 12AU7 and 12AX7 for the amplifier tubes and KT88 series and 300B for the output tubes, not only because of the good sound, but also because they are compatible and widely available and easy to obtain. As you know, even if the vacuum tube has the same model number, the sound is different depending on the manufacturer, so we dare to choose a ball that is easy to obtain so that you can easily replace the taste of the owner and the compatible vacuum tube and enjoy music. Therefore, except for some high-end systems, all but one can be used interchangeably without bias adjustment. Yamamoto: It's a slightly different approach from amps that dare to use vacuum tubes, which are hard to come by, and enjoy the sound.
Yamamoto Acoustic Crafts
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https://www.exclusive-audio.jp/shop/products/list.php?category_id=13
Yamamoto Acoustic Crafts develops a variety of audio accessories. Yamamoto Acoustics' amplifier is a combination of natural wood and brass with a beautiful grain made by utilizing excellent woodworking technology, and the appearance has a warm impression that is different from the above two companies. The wooden chassis, which has a smooth surface and beautifully treated curves, enhances the presence of Yamamoto Acoustics' amplifiers, perhaps because of the woodworking that people have been familiar with since childhood, and the appearance satisfaction is quite high. The charm of wood is a mysterious thing, and people always want to touch any wooden product and try its feel.
The use of cherry wood and ebony, which claim to have a good sound, should also be expected to have a vibration damping effect due to moderate hardness and flexibility, contributing to sound quality. We are working to improve reliability and sound quality by using carefully selected components both in Japan and overseas, such as Yamamoto Acoustics' original products and independently processed capacitors. In addition, non-magnetic brass covers and Teflon material insulation measures are also shrewdly applied.
Yamamoto Acoustic Crafts uses specific vintage tubes such as Western Electronic and Emission Lab for the vacuum tubes used, and creates a dedicated amplifier that allows you to enjoy music that makes the most of the charm of the vacuum tubes. It can be said that it is for those who want to enjoy music to their heart's content with their longed-for vintage tubes. It is a different way to enjoy Astro Electronic Planning by using vacuum tubes that are easy to obtain, increasing the owner's taste and freedom.
The impression of the sound of Yamamoto Acoustic Crafts is softer and gentler than that of the above two manufacturers, as shown by the soft appearance of wood, and you can feel the warmth of a tube amplifier. It can be said that it retains the characteristics of vacuum tubes. I feel like I'm properly deriving the individuality of the vintage tubes I use, and seasoning the sound in a good way. All power amplifiers are of the single type. There is a good outline in the softness, and there is no ambiguity. It also expresses the delicate sound of a single. It is a rich musical expression centered on the high and mid ranges, but the low frequency range is a little more mature. Since it is a single amp, the output is only a few watts. If you want to enjoy the sound to the fullest, highly efficient speakers are ideal.
Yoshishiba Acoustic Industry
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https://www.exclusive-audio.jp/shop/products/list.php?category_id=42
Mr. Yoshishiba, who is the chairman of the executive committee of the Vacuum Tube Audio Fair held in Akihabara every year, is the representative of Yoshishiba Acoustics. It may be the most unique of the four companies. Yoshishiba Acoustics' amplifiers do not have a so-called easy-to-see brand design, and there is not much sense of unity. What they have in common is nostalgia, a retro feel. Each amplifier created by Mr. Yoshishiba has a different and unique design. Mr. Yoshishiba's temperament is more like an artist than a technical craftsman, which is strongly reflected in the design.
It's the same with sound creation, and the idea is completely different from that of manufacturers who faithfully reproduce modern original sound sources, and the sound of tube amps would have been like this in the Showa era. The sound of the amp I longed for in the past was even better than it is now. After all, I want to make the low frequencies feel good, so I am always thinking about how to listen to music comfortably and how to immerse myself in the emotion of listening to music, and I am working hard day and night to research to improve the sound quality of amplifiers. In particular, whether it is a single amplifier or a monaural amplifier, the mid and low frequencies come out firmly, and the sound that appeals to the emotion comfortably when listening is colorful. The key to creating this sound is Yoshishiba Acoustics' original transformer. It is a hand-wound transformer that takes time and effort to arrive at through trial and error. And it is a state-of-the-art technology that we have experience and greedily research on a daily basis to create the ideal sound.
Yoshishiba Acoustics is strongly aware of the sound of European and American amplifiers. I feel that the sound of long-established Western tube amp manufacturers is fundamentally different from that of Japan tube amps, and in order to create a sound that exceeds that, I thoroughly investigate old Western amplifiers from wiring diagrams and components, compare and study them, and utilize them in the sound of Yoshishiba Acoustics.
It is the way of thinking and approach to the sound of the four companies.
