Sarasvati 2A3 integrated amplifier

 

  

 

Etymology of name 


Sarasvatī is worshipped as the goddess of knowledge and the arts such as literature, music, painting and poetry, but also of truth, forgiveness, healing and births.

 

 

 

Sarasvati is a stereo amplifier with an output triode 2A3 MESH EMISSION LABS, inductive coupling, one gain stage/driver, made with high trans-conductance triode and input transformer Clinamen translator/insulator. All the Clinamen techniques based on the natural path of sound are used; viz. the simplest possible design methods which exploits the intrinsic linearity of the active components enhanced by magnetic elements of outstanding class. We can mention, for example, the ‘Electrolytic Less’ technology, the fixed bias and the plate triodes with metal mesh.

We have been able to obtain an integrated amplifier with great musicality which honors the name it bears; great aesthetic taste and an overall compact size.


 


But let’s analyze the circuit topology in detail.

 

The scheme develops on a single-ended circuit, zero feedback, with polarization of the stages all with fixed bias. As usual for Clinamen the active stages are the minimum required to achieve the result, thus only one driver stage built around an EC8010, high trans-conductance triode with unidirectional plate.

 

 

The power supplied to EC8010 is stabilized via a gas-charged valve, therefore with no feedback system. The anodic coil of the EC8010 is made of an ultra-large nucleus Custom Clinamen Permalloy coil, geometrically symmetrical in order to avoid picking up induced noises.


On the advantages of the inductive anodic load as opposed to the resistive one a lot has already been said; this is not the place to go back to it. I will just mention that on an electrical level it allows us to push the final triode in class A2, thus having a greater power transfer, an instantaneous recovery from overload and exploiting as much as possible the trans-conductance of the valve. On the sound it translates into greater micro and macro dynamics, smaller nuances and a much greater sense of realism, especially when the coils are built with high permeability quality materials, such as the Custom Clinamen.

In input we have a Vacoperm transformer, also with ultra-large nucleus and symmetrical design. It is shielded by a Mu-metal container for maximum noiselessness.

The gain in tension offered by the input transformer allows a good sensitivity of the amplifier, which is 400mV for the maximum power.

 

Speaking of power supply, we can say that the 50 Hz network sinusoid is converted in a 100 Hz sawtooth through a direct heating diode 5U4G. The levelling of the sawtooth is carried out through a DOUBLE inductive filter, implemented with only polypropylene condensers (Electrolytic Less). The quality of such power supply is crucial to achieve the performance of which Sarasvati is capable.

 

 

Incredibly low is the output noise, lower than 0.6 mV RMS, result of an advanced masses layout.

 

The wiring is point to point, made with  silver plated copper and Teflon insulation cables; the soldering is implemented with 4% Silver WBT.

 

 

The structure is a 30mm Padouk wood frame, CNC made to allow the insertion of carbon fiber lining which supports RCA and network socket. The upper plate is made from 3mm carbon fiber, which guarantees resistance, beauty and excellent sound. All the drilling is carried out with our CNC machine. The frame is thoroughly impregnated with natural shellac to feed the wood and enhance its natural grain. The finishing is implemented with natural wax.

 


 

Sarasvati can drive speakers with a sensitivity of 90 dB/w/m and above with great dynamics and emotion. The coupling with all Clinamen speakers is particularly successful.

 

It is a listening experience to be made…along the natural path of Sound.

 

 

 

 

 

  

Technical data


  • Integrated stereo amplifier, Single ended with 2 A 3 output tubes
  • 0 feedback ( ne totale ne locale) , single stage high transconductance driver /voltage gain ( EC8010 tube)
  • INPUT : two switchable stereo input RCA
  • Power output 3 watt RMS  A1 class.  5 watt RMS  A2 class
  • Distorsion THD% :  1 watt 0,7% .  3 Watt 1,2% .  4,5 Watt 3,4%
  • Bandwidth  -1 dB : 12 Hz to 50 Khz
  • Input sensitivity: 400mV RMS for 3 watt output . 520 mV RMS for 4,5 watt output power.
  • Residual noise: less of 0,6 mV RMS
  • Power consumption = 110 Watt
  • Fuse : 800 mA delayed. 5x20 mm type.
  • Tubes: 2 x 2 A 3-S Emission LABS ; 2 x EC8010 NOS ; 2 x 0D3 NOS; 1 x 0A3 NOS; 1 x 5U4G 
  • Available with extra charge 5u4G mesh Emission labs
  • Topologia circuitale : 2 stadi attivi single ended 0 feedback. Trasformatori di ingresso Custom Clinamenaudio in Vacoperm . Triodo driver ad alta transconduttanza accoppiato alla finale in maniera induttiva con bobina Custom Clinamen in Vacoperm
  • Trasformatori di segnale a costruzione simmetrica schermati magneticamente in mumetal
  • Bias fisso stabilizzato regolabile con circuito proprietario Clinamen sullo stadio finale e bias fisso anche sugli stadi driver
  • Stabilizzazione "naturale" della tensione di alimentazione degli stadi driver con valvole a gas
  • Alimentazione con diodo a vuoto e doppio stadio di filtraggio induttivo.
  • Power Supply “Electrolytic Less”, per la massima velocità e minima colorazione timbrica
  • Telaio perimetrale in legno massello nobile,   piastra superiore in fibra di carbonio da 3mm di spessore
  • Piastra inferiore di chiusura in ardesia, con funzione di smorzamento di vibrazioni,  con fregi (chiavi di violino)
  • Telaio lucidato a cera 
  • Prezzo 8700 euro con triodi di uscita 2A3 S EMISSION LAB 

NB:  Starting from the next Sarasvati SN3 we will have two 5U4G rectifiers to lower the internal impedance of the power supply and have even more dynamic and articulation in the low register; we will also add a 20mm slate base finely carved with G-clef friezes. As well as being beautiful, this new base helps a lot in the damping of vibrations.









MEASURES

Below are the measurements performed on Sarasvati. The load is 6.8 ohm resistive. The sinusoids related to the powers of 1 Watt RMS, 3 Watts RMS (border of the class A1) and 4.5 Watts RMS (class A2 thrust) are reported. The Fourier analyzes of harmonic distortion are also reported with respect to these power levels. We emphasize the very low distortion rate, if we consider the nature single ended 0 feedback with small triode of power implemented. Then follow the answers to the square wave, also these really excellent if we consider that two signal transformers plus an inductive coupling are crossed. Finally the sinusoid is reported at 20 Hz at 3 Watts, which highlights the goodness and the dimensioning of the output transformer (waveform distortions are not seen).



Sinusoide 1KHz ad 1Watt RMS 
 

FFT a 1 KHz 1 Watt RMS.

THD totale= 0,7% 

   Sinusoide 1KHz ad 3Watt RMS
 

 FFT a 1 KHz 3 Watt RMS.

THD totale= 1,2% 

  Sinusoide 1KHz ad 4,5 Watt RMS 
 

 FFT a 1 KHz 4,5 Watt RMS.

THD totale= 3,4%

   Sinusoide 20 Hz ad 3 Watt RMS 
   FFT 30 Hz 1 Watt RMS
  Square Wave 1 KHz 
  Square wave 10 KHz