Headphone SE amplifier

[Toxicguy]

Hello

At first I would like to give thanks to George for his excellent projects which he shares to the enthusiasts wishing to repeat this or that scheme of the tube amplifier. About two years ago I have repeated his SSE amplifier. I used TAD KT88 tubes and Hammond 1628SEA output transformers. There are some pictures of it. I am very happy with result. The quality of sound has appeared above my expectations.

Now after reading this article Headphone Amp | Tubelab I'm thinking abou build of headphone SE amplifier. Well, for these purpose I have found this output transformer TRANSFORMERS FOR HEADPHONE AMPLIFIERS - model 9351. My headphones are with 250 Ohm impedance.

Unfortunately I'm not so good with schematic calculating, that's why I ask your help:

1. Is this transformer approaching to original diagram without any changes?
2. Using for example 2A3 output tubes, is it possible to reduce B+ voltage to reach less power for headphones output? 100k volume control also will be added.
3. I asked already about Sharp PQ5EV5 voltage regulator. DigiKey is not the best option for me. So, is this regulator ok for general SE project MIC29752 - Linear Regulators - Microcontrollers and Processors ?

Thank you in advance!

 

[Toxicguy]

As I understood correctly the theory, bigger load impedance of output transformer also reduce the power and at same time improves distortion factor. If I'm right, probably 10k transformer (model 8988) is better for my built?

 

[Toxicguy]

One more question - if I want B+ voltage below 300 V for 2A3 tubes (275 V for example), which values of R14 and R25 should I use?

 

[adason]

If you want to use tube amp you already have with headphones, i recomment little dividing network, just two resistors.
I built headphone jack into small box with resistors, and short cable leads go directly to speaker outlet. This way noise and hum is supressed too, and normal volume settings are used.
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