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In my post above I have mention that Srajan is in a way a brainless parrot that repeats the heard and has no ability of desire to understand what was the noise about. His comments that 6E5P and E810F are “close electrical” is a good indication how it works: a manufacture passes wind from behind and an idiot-reviewer runs around him and screams “Hurricane!”

Anyhow, mentioning that Thorens used my 6E5P in out stage I think that it would be deceives to truth if I would not correct another factual error that Srajan used in his article as selling point. Here are two paragraphs from Srajan write up:

The output valves' input capacitance is lower than the power amp's Mosfets by a factor of 1000 of course. Far more importantly, their output current is 30mA. And their output impedance 0.67 ohms. That latter is a shockingly low figure for a direct-coupled tube circuit. It means phenomenal drive over even endless interconnects. Or 600-ohm load happiness as active pro monitors present. Yousa! And for the really curious, yes, the 6E5P's close electrical -- but not pin-compatible -- cousin is the E810F which has a higher transconductance but less anode power dissipation. This preamp circuit would be capable of swinging an ungodly max +/- 60V but is naturally limited by the input signal. A standard 2V input signal translates into roughly a voltage swing of 10 (gain is 16dB). That means overkill headroom for true dynamics. And an unconditional incapacity for clipping the output stage. Ever. It's really a power amp wolf in preamp sheep skin. Blöhbaum runs his original TEP 3800 prototype [lower rights] to drive AKG K-1000 headphones with. Those are beastly inefficient and usually coupled speaker-level to amplifiers putting out 10 watts.

"I know you've lived abroad for half your life and are probably only now discovering much of the hifi scene in your native Germany. It might interest you then to know that both German print magazines and arch rivals at that already published reviews on the TEP 3800. Quite out of character, they agreed with each other and rated it among the best if not the best preamp they ever tested. It's good to observe both the Stereo and Stereoplay tests. The Stereoplay test bench delivered a graph of harmonic spectra depending on output amplitude. This graph shows why this preamp is praised for its transparency. There is no change of the relation between each specific harmonic and each other from the low end of just perceptible whispers to ear-cracking levels. The absolute value of distortion is extremely low. The measured figures of Stereo magazine show 0.0002% @ 1V output. Most high-end people believe that such low distortion will end up in anemic, cold, clinical sound. It's remarkable that especially Stereo magazine -- which is known for favoring some voodoo tricks and beliefs -- praised the musicality of the TEP 3800. Also look at the other values like channel separation of 73dB. Stereo measures that at 10kHz! One footnote: The measured output impedance of 56 ohm is for cinch. The XLR has a stunning 0.67 Ohm output impedance. "

Srajan  said that TEP 3800 uses 6E5P in output stage and I do not exactly understand how the 6E5P might be use in direct-coupling with preamp’s load, what would block DC? Does Frank Blöhbaum in this preamp uses a SS follower after 6E5P?  The most important: where is the 0.67 Ohm output impedance came from? It is obviously that 0.67 Ohm is nether 6E5P anode nether 6E5P cathode. With output current of 30mA that Srajan mentioned the 6E5P has a little bit sub 1kOhm on anode, it is very low but it is not even near 0.67R, unless it run a huge feedback. So, praising the 6E5P as out stage for TEP 3800 preamp I need to say that if the preamp do have 0.67 Ohm output impedance then it has absolutely nothing to do with 6E5P. It would be interesting to chat with Frank Blöhbaum about what he did in there. I would particularly be interested to know what he was trying to accomplish by running 6C19P in a copper chimney. However, it looks like via Srajan interpretation it as much plausible as to have a conversation with a porcupine about the Global Warming.

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