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On this page you will find detailed test results. Many manufacturers avoid giving detailed technical info and they have a good reason - tube amplifiers, in general, do not have impressive specs, especially compared to modern semiconductor amplifiers. You should always keep an open mind and try to hear an amplifier before deciding if that's something you like or not. Do not get discouraged with numbers, because very often you'll be surprised by what your ears tell you. 

The Model 1 is an experimenter's unit and it is our policy to give you an adequate, meaningful and complete information, so you know exactly what is your starting point for future experiments.

The results are presented as they were measured, we did not apply any "makeup" to have them look better than they are.  Notice that square wave oscillograms are taken at relatively high voltage, 8 Volts peak-to-peak (unlike many others that show this waveform at 2.5Vpp or so).  

The measurements are taken with the lowest cost transformer. You can expect to improve performances if you invest in higher quality transformers. Using more expensive transformers will significantly increase price of the unit. We are satisfied with the $$/quality ratio and believe that many of you will be too. Once you are ready to move forward, you can easily upgrade. We are working to offer you high quality transformers at an affordable price, but we do not have a qualified source just yet.

But, first, make sure to follow the golden rule - before making any changes, spend considerable time with the amplifier in its basic configuration. This will allow the tubes to burn-in for maximum performance and you will "learn" the sound of the amplifier, which will serve as a good reference for future endeavors. 


1. Triode mode, square wave response:

1.1. open loop, 1kHz, 8Vpp:


1.2. open loop, 10kHz, 8Vpp:


1.3. negative feedback, 1kHz, 8Vpp:


1.4. negative feedback, 10kHz, 8Vpp:


2. Pentode mode, square wave response:

2.1. open loop, 1kHz, 8Vpp:


2.2. open loop, 10kHz, 8Vpp:


2.3. negative feedback, square wave, 1kHz, 8Vpp


2.4. negative feedback, 10kHz, 8Vpp:


3. Output harmonic content, fundamental frequency 200Hz, power 1W:

We reserve the right to change the specification at any time and without any advance notice. Feel free to contact us for the latest available info.

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