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Commentator: Srajan Ebaen
Financial Interests: click
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Component retail: €40.000/pr


As the absence of the usual equipment listing gives away, this is not a formal review. It's simply a 'they exist' feature. It's about a pair of very expensive utterly exclusive amplifiers. Only one pair currently exists on the planet. While I will provide casual listening impressions in the system of my friend who commissioned them, the main purpose today is to revitalize a notion. Have audiophiles approach gifted designers with custom commissions. This helps such individuals to advance their respective state of the art outside the usual commercial limitations. During the Renaissance it was counts and duchesses who commissioned composers and painters for masterworks we enjoy until today. With hifi even people of more modest means can become patrons to the arts. All it takes is an idea, desire and approaching the right designer.



Vilobha is Sanskrit for seduction. When my friend Dan heard Sasa Cokic's very affordable Trafomatic Audio Aries integrated in his system—I occasionally bring review loaners to Dan for an impromptu session—he spontaneously asked whether I thought Sasa capable of designing a truly world-class SET amplifier around his favorite triode, the Eimac 75TL.


Having previously owned such an amplifier from Josh Stippich of Electronluv, Dan had fond memories of its sound, less fond ones of finicky mercury vapor rectifiers and noise. Dan of course knew of my custom Kaivalya amps which I'd commissioned from Sasa the year previous. When I confirmed that the Serbian auteur had already collaborated with a US valve maniac on 250TL and 450TL triode amps where Sasa's custom transformers support 4000 volts on the rails, Dan approached the Trafomatic man with a proposition.


The amps he wanted would have to be ultra quiet to drive his 100dB Voxativ Ampeggios. They had to have sufficient power for his new Aries Cerat Gladius which was being built in Cyprus. And most importantly they had to sound stunning.


Translating this into a circuit and matching cosmetics was left to Sasa. After three months of non-stop involvement, seven very complex output transformer prototypes and sundry detours, the finalized amps arrived at Dan's house December 10th. Sasa, his partner Milorad Despotovic and assembler/wiring man Goran Blazic would be in Switzerland on the 12th for the maiden audition. I was invited to attend.


To prepare for the occasion, I asked Sasa to call me for a run-down of the circuit highlights. Since he and Dan had entrusted me with christening the amps, I'd revisited the Sanskrit origins of my Kaivalya to suggest 'seduction' which Dan and Sasa liked enough to adopt.


The Vilobha monos are paralleled single-ended 20-watt amplifiers. Their signal path consists of a C3m input pentode in triode connection which is direct-coupled to an EML 45 driver that's interstage-coupled to two paralleled 75TL. One EZ81 rectifier supplies the input tube, two 6D225 act as 15-second high voltage delays.


For onboard iron there's a grid choke to bias the C3m with an LED bypass; two 10H choke filters for the high-voltage supply; two 10H 100mA choke filters for the low-voltage supply; one double C-core transformer with separate windings for the high/low voltage supplies; one double C-core transformer with separate windings for all the tube heaters; and one double C-core output transformer that's claimed to be flat to 70kHz.



The lateral heat sinks couple to the heater stabilizers for all tubes on deck. The tube covers combine aluminum and acrylic and the letters on front of each chassis were CNC-machined, then sand-blasted and finally bonded to the enclosure.


"The output transformers took me a long time to get right due to the high impedance of the 75TL. Where a 300B presents a 2K output impedance, this triode has 14K. Paralleled that still equates to 7.000 ohms which is a lot.


"Unlike with your push/pull Kaivalya monos, here I needed absolutely no feedback through the interstage transformer to tweak the THD behavior. The 45 drives the output triodes with such low harmonic distortion that no correction was required at all. There is a local feedback loop between the 75TLs and binding posts but it's a mere 0.5dB through the output transformer. Noise on my 100dB Rethm Saadhanas is nil so Dan should have no issue on his Ampeggios. I put the input sensitivity at 2 volts to allow good control for any of his preamplifiers. I run the output tubes at 1.100 volts and bias them at 45mA. This not only made for the best sound but safe long-term operating parameters."

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