"SATYA" E55L Monotube headphone amplifier

SATYA is the most extreme offer from Clinamen as far as headphones amplifiers are concerned. We are positive that it is the top of the range of headphones amps. Its architecture is as simple as it is outstanding and it is built around only one valve – the E55L.

It is a pentode with a magnoval base, a professional valve with a guaranteed life of 10,000 hours. Its electrical parameters are exceptional - 30 fold gain with an internal resistance of only 650 ohms at the chosen operating point. One of these parameters stands out; its trans-conductance of no less than 45mA/V…these numbers are well beyond the ones usually found in the Hi-end sector. Of course we use it connected to a triode achieving the maximum power of 0.8 Watts rms with a distortion below 1% WITHOUT ANY FEEDBACK WHATSOEVER. This valve claims to have a 10,000 hours life span; it uses outstanding technology and in our operating point it is used at 60% of its anodic dissipation; therefore the lifespan of the valve is the least of your worries.

In the image below you can appreciate the extraordinary linearity of the E55L connected to a triode mode. Even with values of anodic current of 30 mA the coefficient of amplification stays consistent at 30 and the internal resistance well below 1,000 ohms.

The high trans-conductance of the E55L has another outstanding effect: the extra quietness of the active device. In a headphone amplifier this is an absolute must.

The study of the resting point of the valves was aimed at favoring the linearity without stressing the valve unnecessarily. Indeed we have a power exceeding half a Watt, which we consider more than enough for headphones listening. Below there are some examples of the resting points examined. Please note here, too, the extreme linearity of the curves (equal spacing between them when the grid tension varies).


The circuit is extremely simple and for this reason it uses custom components of absolute outstanding quality. A transformer with Vacoperm nucleus that works as a tension shifter and decoupler; a resistive circuit potentiometer with 24 settings and a Custom Clinamen output transformer also made of Vacoperm. Obviously, again, no feedback. The custom Clinamen output transformer has two secondaries that allow it to set the output impedance on the standard 32 ohms or on 128 ohms, thus covering a wide range of usage of headphones. The switch can be operated by the user and it allows them to set it on MUTE as well.

On the front there are two millivoltmeters which, thanks to the inside calibration show the mA reading of the polarization (resting current) of each valve. We chose them instead of the standard milliameters because voltmeters are connected in parallel and therefore they are not crossed by the signal current; the result is a better sound and more reliability. As well as being quite dramatic looking, they are also perfect indicators of the good working order of the circuit or the efficiency of the final valves. Their reading must be between 40 and 50 mV.

The filaments of the E55L are fed by continuous current through two independent stabilized power supplies.

There are three available inputs commutable through a front selector, which through a transmission stick controls the Palazzo commutator just behind the RCA connectors. This shortens the journey of the signal and minimizes the disturbance pick up.

The power supply is built exclusively with condensers made of cork cushioned polypropylene, in order to have the best dynamics and correspondence to the musical signal, with an absence of timbral hues, reliability and endless life span

The rectification of the alternate tension is carried out with EZ81 vacuum diodes and we have no less than three inductances to filter the anodic tension to perfection. Clearly the cabling is end-to-end using annealed silver plated OFC with Teflon insulation. Soldering with WBT 4% silver content solder.

The chassis is made of 3mm anticorodal painted metallic Venus grey with laser screen printing. The logo Clinamen and the name SATYA are very clear thanks to the CNC machine process and a backlight that through an opaline material shines the light of two orange LEDs (this color has been chosen to match the valves’ filaments). The instruments are backlit by blue LEDs. 


Price:  5990 euro

Custom painting : 150 euro

Coupling ERGAL  Clinamen feets : 200 euro


  • Class A triode  zero feedback design
  • mono-tube amplifier, with super high trans-conductance E55L ( triode connection) coupled to output with Vacoperm custom Clinamen transformer 
  • Tubes: 1 x EZ81/6CA4. 2 x E55L
  • Custom Clinamen input step up transformer ( RATIO 1:2) , with Ultra large Vacoperm cores. 
  • Power output ( with THD less of 1% ) --> 500 mWatt rms
  • Maximum output power (THD around 4% ) --> 800 mWatt RMS
  • Input sensitivity ( for power output of 500 mW rms) --> 900 mVolt rms
  • Switchable output impedance : 32 or 128 ohm
  • 3 RCA (unbalanced) input, switchable with rotatory selector
  • Mute
  • Bandwith at -1 dB : 16 Hz -->67 KHz
  • zero feedback design
  • DC stabilized filaments power supply, one for every tubes
  • Raddrizzamento a valvola con EZ81
  • Inductive anode filtering with individual L-C decoupling for the two channels
  • Polyprpylene Anode Capacitor, damping with cork
  • Residual noise: 0,20 mVrms
  • Power consumption: 37 Watt
  • Dimension: ( including front Knobs ): L:50cm D: 28 cm H:20 cm
  • Weight : 12 Kg