The Shangri-La electrostatic earphones with a complete tube OTL amplifier on direct glow triodes have become famous in the individual sound market, perhaps the only development that could compete with the Japanese company STAX in the relatively close serial market of electrostats. Today we will talk about isodynamic headphones, devices with less pathos positioning, which at the same time are practically inferior to electrostats in quality.
A Brief History of Isodynamic Headphones
Headphones appeared at the end of the XIX century and were intended, with rare exceptions, for professional tasks, for example, telephone exchange operators, sound recordings and radio broadcasts. There were also rare, in-channel options for listening to music on the phone, however, they did not gain wide popularity, and closer to the 20th they all forgot about them.
The mass production of household stereo headphones began in the second half of the 20th century, about a year after the first commercial stereo records appeared. The intense search for optimal acoustic solutions for this form factor has led to the emergence of isodynamic headphones. The ID1 serial isodynamic headphones were created in 1972 by Wharfedale from the UK.
Let me remind you that the isodynamic is a variant of the classic electrodynamic emitter, which is close in design to tape tweeters. In it, a meanand-like conductive path, acting as a coil, which interacts with rod magnets, is deposited on a thin membrane. Due to the long track length, it is possible to increase the resistance to acceptable values. Which differs significantly from a similar tape emitter, where, due to the low resistance, a matching transformer is needed.
Ananda BT, as the next stage of evolution
So, the device that caught my attention is Ananda BT, created by HiFiMan. Audiophiles-old believers will immediately pay attention to the presence of a wireless interface and will probably distort faces in a grimace of disgust. After all, wireless headphones are “not true”. Therefore, for starters, we’ll quickly look at the ability of Bluetooth to wirelessly transmit audio with relatively high fidelity.
Indeed, the early versions of the Bluetooth wireless protocol were born about 20 years ago, and it was problematic to use them for high-quality audio transmission. Meanwhile, after September 7, 2016, when the seventh iPhone appeared without the usual 3.5 mm jack, it became increasingly difficult to do without it.
It is known that audiophiles-old-phages usually don’t listen to music from the phone. At the same time, what do other music lovers who are not ready to sacrifice quality at the same time for the sake of convenience and convenience for the sake of quality? Today, various codecs are widespread, which, according to manufacturers, are able to bring the quality of wireless transmission closer to the quality of CD and hi-res. These codecs usually include aptX HD, LDAC and HWA (which is equipped with a monitored gadget).
Also, the good old SBC is not as bad as is commonly believed. On a habr more than once raised a question about real possibilities of this codec and found out that it is close in characteristics to the ones listed above, especially if software restrictions are eliminated, as described here. All the described options are available in monitored headphones, which satisfies the requests of those who are willing to slightly upgrade SBC, and those who rely on publicized commercial codecs.
Further directly about the headphones. The model was announced back in 2019, and according to information from last year, it became clear that we are talking about a fully active version of the Ananda model. Accordingly, connection to the source will be possible using a digital interface, analog switching is not provided at all. Also, there are no familiar controls, such as volume controls, rewind buttons and answer calls. The latter is explained by the fact that the headphones, in principle, were not conceived as a telephone headset and do not have a built-in microphone.
The kit includes an external remote microphone, which is attached to the cases of the right earphone. It is quite suitable for transforming Ananda BT into a headset for gamers, but it will hardly look like an adequate option on the street. This modest functionality is a controversial decision, but it is far from always a drawback, because many people don’t use headsets for talking, and the gadget is positioned primarily as a device for music.
The wired predecessor of the device weighed 400 g, which is logical, given the massive permanent magnets that provide impressive amplitude capabilities (and, consequently, volume). In the Bluetooth version, the mass is also affected by a high-capacity battery, a DAC with an amplifier, and also a digital signal reception module. At the same time, the engineers managed to fit all this within a half-kilogram critical mark. For wearing something heavier on the head (without a cervical exoskeleton or collar splint) for many seems to be, if not a serious economic problem, then something akin to a kind of exercise machine for the neck muscles.
The package includes a standard USB cable, as well as a case for transportation. The headphones are equipped with a double adjustable headband that can be easily sized to fit. The ear pads are made of leather and textile, their shape repeats the anatomically shaped oval shape of the cups. The acoustic design is open, which may not appeal to fans of “intimate listening”, but, in my opinion, is optimal from an acoustic point of view.
The device charges for two hours and thirty minutes, after which it works autonomously for 10 hours. For 2020, this is far from a record, but perhaps it is worth considering the presence of high-performance DACs and balanced amplifiers, independent for each of the drivers. Headphones can receive and decode digital signals up to 24/192 kHz via USB cable and 24/96 via Bluetooth. Detailed specifications are available. here.
For everyone who is familiar with the characteristic features of playback using isodynamics, there will be no “revelations” in the sound. This is exactly the “same” honest sound, which significantly surpasses most traditional dynamic headphones in terms of frequency response unevenness. Using the wireless model, you subconsciously expect compromises and notable digital artifacts. In my subjective experience, they are not. In this case, we are talking about full-fledged isodynamic headphones (with a relatively flat frequency response), excellent dynamic capabilities and what audiophiles are called “high detail”.
A characteristic feature of isodynamic drivers is listening without fatigue, even with prolonged use and high volume. If there is a difference with the wired version, then it can most likely be determined in measurements, it is invisible by ear. Perhaps people with Golden Ears, having set a goal, will be able to identify it in blind tests. However, if you resort to a trivial comparison, then determining it is extremely difficult, if at all possible.
In my opinion, with the help of Ananda BT you can listen to music with pleasure, it can be done with equal success in two ways – by wire and without. For other purposes, they are not very suitable. This is not the cheapest solution, but for this money the user gets not only headphones, but also an amplifier, DAC and freedom from wires.
In our catalog you will find headphones presented in the review, as well as many other modern electronics. With us you can easily find acoustic systems, headphones, amplifiers, soundbars, and other useful devices. The assortment includes warm lamps, vinyl and other joys for lovers of technoarchaics. We did not forget about cold transistors and very frosty digital devices.