Founded in 1994, Pathos Acoustics is the brainchild of three Italian hi-fi enthusiasts: Gaetano Zanini, Gianni Borinato and Paolo Andriolo. Pathos electronics combine exceptional design and high-end construction. The trio?s approach to music restitution involves breaking free from any type of precept in order to focus on an audiophile ideal: to deliver music in the most authentic way possible. This approach gave birth to InPol technology (Inseguitore Pompa Lineare), patented by the Italian manufacturer. This hybrid tube amplification technology is the guarantee of high-fidelity music reproduction.
Italian design
The Pathos Inpol Ear headphone amplifier inherits the brand’s traditional esthetic features while showcasing a daring design, if not to say extravagant. With its 12kg of mass and generous size, the Italian device is hard to miss. Its heavy, steel body houses meticulously selected components and a large power transformer. Boasting a slick, glossy finish, the Pathos Inpol Ear is fitted with two massive aluminum ears which, bearing the shape of the manufacturer’s name, act as heat sinks. The 6922 Electro-Harmonix tubes can be seen through two holes on the top panel. The tubes are protected from shock by a system consisting of three aluminium plates. The front panel, which presents a simple and clean design, includes an aluminum volume potentiometer.
Extensive range of connections
The lower part of the front panel includes a power button, a source selector and an LCD display. The red characters indicate the selected source as well as the sound level. A USB port (Type A) and three headphone outputs (6.35 mm and two XLR) are also located on the lower front panel. In addition, two preamplified outputs (RCA and XLR), give the Pathos Inpol Ear?s the ability to be used as a stereo preamplifier when combined with a power amplifier and a pair speakers.
High-efficiency DAC
When fitted with the optional HiDac EVO, the Pathos Inpol Ear headphone amplifier benefits from a high-end DAC, the famous ESS Sabre 9018K2M. This device can thus handle 32bits/384kHz PCM audio stream read from a USB or network storage device via its S/PDIF digital inputs. Once connected to a computer via its USB port, it can also decode DSD64 and DSD128 files. The amplifier can be connected to the local network using an Ethernet connector or a WiFi network (WiFi USB module included). In addition to giving the Pathos device access to all the audio files shared on the local network (NAS, connected PC), this also allows the amplifier to stream music wirelessly from an iPod, iPhone or iPad using the AirPlay protocol. An iOS and Android compatible control app allows you to easily manage playback using your smartphone or tablet.
InPol technology
The Pathos Inpol Ear headphone amplifier adopts a fully symmetrical double Inpol design. The InPol hybrid amplification technology it implements uses a circuit fully balanced in Class A, without any counter-reaction. The tension of the input signal is amplified entirely by tubes in order to protect its harmonic integrity. The transistor is in follower configuration and delivers enough power to supply the transducers with gain = 1, producing the same effect as if the headphones were directly driven by the tubes. In addition to the fact that it offers an extremely faithful restitution of the original signal, this configuration allows the manufacturer to obtain an input level 25 to 50% superior to that of a traditional class A conception. All of this while maintaining a low output impedance to optimize the damping factor – a guarantee of perfect control over the headphone?s transducers. The attack of each note is more lively, low frequencies have a real impact without becoming muddy, and fade outs are better controlled.
Appropriate for all types of headphones
The Pathos Inpol Ear headphone amplifier?s specs sheet is quite astonishing: the amplification power available is superior to 500 mW into 600 Ohms via the jack output, and can reach up to 10 Watts into 32 Ohms, while ensuring a very low harmonic distortion rate. Suffice it to say that this amplifier can easily power any type of headphones available on the market. Moreover, the Italian manufacturer announced a notably extensive frequency response ranging from 2 Hz to 200 kHz with a difference of +/- 0.5dB between highs and lows. As such, all the conditions for an optimal listening experience with high-resolution audio files are met. it is important to note that the two Texas Instruments Burr Brown PGA2310 volume controllers used for this amplifier offer extremely precise sound increments. This is the reason why the Pathos Inpol Ear uses an impulse volume potentiometer instead of a rotational model, as it allows the user to increase or decrease the volume by one increment by moving the potentiometer to the right or left. With 180 increments of 0.5dB each, it is possible to adjust the volume with perfect precision.
Test conditions
In order to review the Pathos Inpol Ear headphone amplifier, we called upon no other than the Focal Utopia headphones. This flagship of the French manufacturer?s headphone range is an open back over-ears model featuring pure Beryllium M dome Focal transducers. The manufacturer spent several months designing a driver optimized for close-range listening sessions. In order to comply with unique constraints which differ from those associated with a speaker driver, Focal designed a brand new cone – named M – here composed of pure Beryllium, like the tweeters of the Utopia speakers. This extremely rigid metal ensures an outstanding rise in frequencies and a significant decrease in distortion.
Once we had these headphones in hand, the first surprising thing was their weight (490 g), despite the use of carbon fiber for the headband. While we thought that a prolonged listening session would be tiring, we were quickly reassured: once we placed the Utopia on our head, we found its headband and thick memory foam earpads – covered with leather – very comfortable. The earcups are wide and the pressure applied to the head and temples is evenly dispersed. The most surprising part is the sensation of not even wearing headphones, as everything around is clearly audible. A quick look inside the earcups allows you to see their internal structure, which lets air flow around and behind the transducers. These headphones are completely open and should therefore be used in a quiet environment.
Once connected to a computer via the USB B port, we used the Pathos InPol Ear headphones amplifier to listen to online streaming services as well as CD-quality and HD audio files. The connection to the local network allows you to use the AirPlay protocol and gives you access to the audio files shared on a local network using the dedicated app.
Listening impressions
We might as well say it straight away, the Pathos-Focal combination does not aim for an exaggerated restitution. No raucous bass, deliberately boosted mediums, or flashy highs here. To the point that the listening experience may be disappointing to some. Nevertheless, basing your opinion on this first impression would be missing the point: this pair delivers music accurately, precisely, and honestly. This last point is especially important as we never noticed any sound coloration during our listening sessions. Each vocal inflection, each touch of a string, each brush of a cymbal is delivered with its proper intensity, in full compliance with the original intention. Some would mistake this neutrality for a lack of character. Listening more closely reveals that the small additions offered by other amplifiers and headphones are, in fact, too much. With the Pathos amplifier in charge, the lows are deep and refined, but never burdensome or out of place. The vocals easily stand out from the instrumental background, and the tone and articulation are perfect. The higher range of the spectrum shines without excessive brightness and is both clear and soft. Each of the soundstage?s elements is right where it should be – nothing is forgotten, nothing is added. The music is expressive and surrounds the listener, so much so that we?d forget we were using headphones. This Pathos-Focal pair works for the music with a benevolent neutrality: all the music, only the music.
