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Becoming a believer in dc for filaments ......

I have always believed that it was better to have ac on the filaments where possible because it sounded better, but at least for this 26/813/813 set amp I have bread boarded, I am finding that hard to prove to my ears. I started out by going to dc on the 813 tubes because using ac on them is almost impossible with out hum. I used a homemade ac to dc rig consisting of a 25A bridge, a 10k uf/16v cap a 1 ohm resistor, a 15k uf cap, and a small choke. I put one on each of the 10v filament trans for the two 813's in the one channel breadboard.That worked well and I was not able to hear a difference in the overall sound of the amp. I left the 26 input tube on an ac filament.
It still had a low hum, too much hum for my liking, so this morning I threw in the towel and put another of the ac to dc rigs on the filament supply for the 26. No more hum. The surprising part to me is that after about an hour of listening to various types of music and switching back and forth a couple of time between ac and dc for the filament, I really could not hear any difference. So at least for this amp, the dc stays on all filaments. Now if I can jut get rid of that pesky little buzzzz .....



Edits: 10/27/16

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Topic - Becoming a believer in dc for filaments ...... - vinnie2 05:30:25 10/27/16 (86)

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