Aries Cerat Collatio Single Ended OTL tube amplifier

Stavros from Aries Cerat just send me the info about Collatio Single Ended OTL tube amplifier...

Welcome to the world of the first True Single Ended, True Class A, output-transformer-less te amplifier, and forever change the way you listen to your speakers.

All tube OTL amplifiers use SEPP, cyclotron or Mr. Futterman’s variations. All these are push-pull amplification stages. They can claim single ended, but they are push pull topologies. Feedback is mandatory in this designs to cancel out the artifacts generated by the problems of not true complimentary driving of the signal, and of course cross-over distortion. Some clever variations have been presented on the market during recent years, but they are nevertheless push pull topologies with many dbs of negative feedback, some of them use up to 60db of degenerative feedback. Of course, these amplifiers are not Class A devices.

Almost all of these ideas were implemented in our lab, trying to create a State of the Art OTL amplifier, but we would always want more, going the extra mile (or two).

After years of testing and lots of prototypes, the Collation amplifier is ready to give another meaning to the words signal transparency.

Our amplifier uses our own proprietary design, and it is in fact a transconductance amplifier, i.e. a current amplifier. Current amplifiers have their own technical and sonic advantages, and if especially matched with highly efficient horn speakers, are simply unmatched.

The output stage is a reactor loaded , parafeed stage, which is consisted of sixteen 6c19p tubes per channel. This small envelope tube, is a very low internal resistance tube, capable of large current swings and was much preferred over the usual OTL tube candidates in terms of bass slam and timbre. Also it is very cheap tube to resplace. A full 32 tube changeover costs far less than a single high quality 845 tube.

The tube bank is biased at 2.3A! For reference, any OTL on the marker giving 25W, is biased at around 200~300mA. The output stage is a true single ended power gain stage and thus can only operate in Class A.No global or local feedbck is used.

Output is provided by a highest quality film capacitor, which is rated for continuous 80A peaks without distortion or heating. This creates a bullet proof shield between your expensive drivers and any mishap you can throw at the amplifier.

Voltage gain and driver stage, is also of unique design. Our proprietary tube stage is a inverted-direct coupled choke loaded Siemens E280F tube, giving a driver bandwidth of over 150Khz, with very large linear voltage swing,highest slew rate and minimum distortion.

Highest quality power supply is half a story told in an OTL amplifier, especially
in a SE one.

We use 5 toroid transformers power supply.Filaments, have their own separate transformer, as well as the driver stage and bias supplies.All power supplies are choke regulated,even the filaments supplies.A total of 16 chokes are uses for filtering and loading, along with very high speed/very high current capacitors from Vishay and Nichicon.

The power supply is biuilt without any compromises, and resulted in this extremely
heavy audio machine. It would be not a hyperbole to state that this is the most robust power supply in the tube market today.

The Collatio amplifier is a truly unique design and is a real highest performanceaudio machine.

• Power Rating: 20W
• Full power Sensitivity: 0.5Vrms
• Power Bandwidth: 15Hz ~ 110Khz
• Noise floor: < -110db
• Tube list: 32 x 6C19P, 2 x Siemens E280F
Dimensions: 460 mm W x 560 mm D x 460 mm H
Weight is 110Kg each, unpacked.

Matej Isak Mono and Stereo ultra high end audio magazine All rights reserved, 2012 None of the original text, pictures, links or files can be re-pritend or used in any way without prior permission!