#26 has typically 7k6 plate impedance (135V, -10V, 5.5mA) so at least 30k anode load requiring.
If you want it as inductive load, at least 240H recommended.
My #26 preamp has active load (SS CCS, Low Z output) to drive parafeed mode 400H TVC!
If you want it as inductive load, at least 240H recommended.
My #26 preamp has active load (SS CCS, Low Z output) to drive parafeed mode 400H TVC!
With plate-to-line transformer, the plate load of 26 will be determined not by the transformer, but by what is connected to its secondary. Say with a power amp input of 100K, the load seen by 26 plate is practically infinite.
The way I can see the problem isn't the load if you use a line output tx 15k:600 the gain is very near a buffer or very low gain if you use vinyl as source, if you use CD, streaming or PC/laptop no problem at all.
Yes
BUT still You have to place couple of hundreds Henry-s in primary inductance
because of good LF band.
And if You want to keep amplification of the tube stage, You will have to put same amount of Hy in secondary
Ending with enormous number of turns not just in primary but in secondary too - leading in tremendous increase of capacitances and Ls. Final result will be total loss of H band and huge phase shift...
26 plate resistance at its best operating point is 7.3K. The primary of K-400 has Z of at least 15K at 20 Hz (signal level dependent), which results in about 1 dB roll-off at this frequency. It is in agreement with the data sheet. Frequency response graph of K-400 shows no HF anomalies; low capacitance winding technique has been used. HA-133 is -1 dB at 30 Hz and 40 kHz with 15K source; by extrapolation about -1 dB at 20-50,000 with 7.5 K source. K-400 and HA-133 are the pinnacles of this type of transformers.
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