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)
- RE: Becoming a believer in dc for filaments ...... - twystd 12:25:50 11/01/16 (0)
- it was a Momma Mia moment... - vinnie2 04:45:14 10/28/16 (13)
- RE: it was a Momma Mia moment... - Tre' 14:30:02 10/28/16 (12)
- RE: it was a Momma Mia moment... - vinnie2 15:20:49 10/28/16 (11)
- RE: it was a Momma Mia moment... - Tre' 15:57:31 10/28/16 (10)
- RE: it was a Momma Mia moment... - vinnie2 17:21:39 10/28/16 (9)
- RE: it was a Momma Mia moment... - SteveBrown 06:25:58 10/29/16 (6)
- RE: it was a Momma Mia moment... - vinnie2 08:13:06 10/29/16 (5)
- RE: it was a Momma Mia moment... - SteveBrown 08:15:56 10/29/16 (4)
- RE: it was a Momma Mia moment... - vinnie2 08:40:07 10/29/16 (3)
- RE: it was a Momma Mia moment... - PakProtector 06:55:58 10/31/16 (2)
- RE: it was a Momma Mia moment... - vinnie2 10:38:31 10/31/16 (1)
- RE: it was a Momma Mia moment... - PakProtector 06:28:06 11/07/16 (0)
- Wow, the wonder you are having buzz and hum issues... - Cougar 18:31:10 10/28/16 (1)
- RE: Wow, the wonder you are having buzz and hum issues... - vinnie2 18:45:42 10/28/16 (0)
- Put that project in a proper chassis/enclosure.... - Cougar 09:16:30 10/27/16 (56)
- DC on the Mains - Triode_Kingdom 13:57:45 10/27/16 (54)
- Neutral to Ground voltage? - Chip647 14:48:05 10/27/16 (53)
- I called my Electrician buddy today.... - Cougar 20:19:22 10/27/16 (51)
- RE: I called my Electrician buddy today.... - Triode_Kingdom 20:53:31 10/27/16 (50)
- But wait. - Michael Samra 03:57:07 10/28/16 (49)
- RE: But wait. - Triode_Kingdom 07:50:59 10/28/16 (48)
- RE: But wait. - Steve O 11:31:53 10/28/16 (47)
- RE: But wait. - Triode_Kingdom 13:30:36 10/28/16 (46)
- RE: But wait. - Steve O 14:37:29 10/28/16 (45)
- RE: But wait. - Triode_Kingdom 20:34:52 10/28/16 (44)
- RE: But wait. - Steve O 07:57:38 10/29/16 (43)
- RE: But wait. - Triode_Kingdom 15:52:16 10/29/16 (42)
- RE: But wait. - cpotl 17:48:02 10/29/16 (40)
- RE: But wait. - Steve O 19:05:09 10/29/16 (39)
- RE: But wait. - cpotl 04:46:52 10/30/16 (36)
- RE: But wait. - Steve O 05:29:53 10/30/16 (35)
- RE: But wait. - cpotl 08:49:29 10/30/16 (34)
- No fair using a filter :) - Triode_Kingdom 13:57:10 10/30/16 (32)
- RE: No fair using a filter :) - cpotl 15:02:44 10/30/16 (31)
- Still Not Valid - Triode_Kingdom 21:29:23 10/30/16 (29)
- RE: Still Not Valid - dave slagle 06:37:15 10/31/16 (1)
- RE: Still Not Valid - cpotl 10:58:46 10/31/16 (0)
- RE: Still Not Valid - cpotl 03:08:21 10/31/16 (26)
- RE: Still Not Valid - Triode_Kingdom 12:03:04 10/31/16 (1)
- RE: Still Not Valid - cpotl 14:34:03 10/31/16 (0)
- Another nice analysis... - Steve O 11:13:13 10/31/16 (23)
- RE: Another nice analysis... - dave slagle 14:31:44 10/31/16 (22)
- RE: Another nice analysis... - cpotl 07:47:09 11/01/16 (0)
- RE: Another nice analysis... - Steve O 16:15:31 10/31/16 (20)
- RE: Another nice analysis... - dave slagle 08:42:27 11/01/16 (18)
- RE: Another nice analysis... - Steve O 09:46:25 11/01/16 (0)
- RE: Another nice analysis... - cpotl 09:32:44 11/01/16 (16)
- RE: Another nice analysis... - dave slagle 11:52:26 11/01/16 (15)
- RE: Another nice analysis... - cpotl 12:33:47 11/01/16 (14)
- RE: Another nice analysis... - dave slagle 14:27:15 11/01/16 (13)
- RE: Another nice analysis... - cpotl 15:27:08 11/01/16 (12)
- RE: Another nice analysis... - dave slagle 20:20:50 11/01/16 (11)
- RE: Another nice analysis... - Steve O 21:13:15 11/01/16 (10)
- RE: Another nice analysis... - dave slagle 05:31:37 11/02/16 (9)
- RE: Another nice analysis... - Steve O 06:34:39 11/02/16 (8)
- RE: Update...Another nice analysis... - Steve O 10:01:15 11/02/16 (7)
- RE: Update...Another nice analysis... - dave slagle 06:35:20 11/03/16 (6)
- RE: Update...Another nice analysis... - Steve O 08:04:49 11/03/16 (2)
- RE: Update...Another nice analysis... - dave slagle 09:32:13 11/03/16 (1)
- RE: Update...Another nice analysis... - Steve O 09:44:16 11/03/16 (0)
- RE: Update...Another nice analysis... - cpotl 07:44:45 11/03/16 (2)
- RE: Update...Another nice analysis... - dave slagle 09:27:09 11/03/16 (1)
- RE: Update...Another nice analysis... - cpotl 07:05:22 11/04/16 (0)
- RE: Another nice analysis... - cpotl 19:40:08 10/31/16 (0)
- Nice analysis: Right on the mark IMO (nt) - Steve O 17:19:35 10/30/16 (0)
- Independent duplication of the phenomenon is a good thing (nt) - Steve O 13:15:36 10/30/16 (0)
- Measurement - Triode_Kingdom 21:04:48 10/29/16 (1)
- RE: Measurement - Steve O 05:57:52 10/30/16 (0)
- RE: But wait. - Steve O 17:40:00 10/29/16 (0)
- RE: Ground issues? - deafbykhorns 15:38:50 10/27/16 (0)
- RE: Put that project in a proper chassis/enclosure.... - vinnie2 11:56:51 10/27/16 (0)
- RE: Becoming a believer in dc for filaments ...... - deathtube 667 06:58:08 10/27/16 (1)
- RE: Becoming a believer in dc for filaments ...... - vinnie2 07:37:21 10/27/16 (0)
- RE: Becoming a believer in dc for filaments ...... - Triode_Kingdom 06:50:24 10/27/16 (5)
- RE: Becoming a believer in dc for filaments ...... - vinnie2 07:34:09 10/27/16 (1)
- RE: Becoming a believer in dc for filaments ...... - deafbykhorns 15:29:42 10/27/16 (0)
- RE: Becoming a believer in dc for filaments ...... - used-hifi 07:08:03 10/27/16 (2)
- Ultrasonic Supply - Triode_Kingdom 08:08:34 10/27/16 (1)
- RE: Ultrasonic Supply - used-hifi 09:32:37 10/27/16 (0)
- Yep - now become a believer in chokes! - andy evans 06:07:06 10/27/16 (5)
- RE: Yep - now become a believer in chokes! - Paul Joppa 11:08:48 10/27/16 (2)
- do you know of any product that might work in it's place? - vinnie2 12:14:02 10/27/16 (1)
- RE: do you know of any product that might work in it's place? - Paul Joppa 15:45:10 10/27/16 (0)
- RE: Yep - now become a believer in chokes! - vinnie2 07:30:59 10/27/16 (1)
- My 01A preamp filament supply/PSU - andy evans 07:45:58 10/27/16 (0)