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Old 7th May 2012, 08:55 PM   #81
tim614 is offline tim614  United States
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Thanks allot guys!
as for LOAD LINE i need to learn how to do that.
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Old 7th May 2012, 08:58 PM   #82
tim614 is offline tim614  United States
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as of now with the 4v on the cathode, i like the sound allot better, just that i wanted to see if i have room to tweak it, ive read that these 6n6p like to be run hotter.
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Old 8th May 2012, 04:51 AM   #83
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I only use led's in my amplifer gain stages, cathode follower stages, phase inverter stages, and biasing for power tubes.... Been doing it I believe before it really started to catch on...I have saved many threads written by others who used to flame me for doing it.....
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Old 11th September 2012, 02:20 AM   #84
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Quote:
Originally Posted by Osvaldo de Banfield View Post
I believe it degrades audio quality adding semiconductor alinearities and destroying tube sound. Also, I strongly dislikes mixing tubes and semiconductors in a set. Bit it is only personal taste.
I agree completely, ANY semiconductor in a tube circuit/PSU will kill the sound. I tried semiconductors in the PSU, cathode, anode etc. Don't do it. I know there are some "gurus" out there telling us "no, no, you will not hear any semiconductor nastiness with my CCS" oh please...

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Old 11th September 2012, 02:24 AM   #85
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Quote:
Originally Posted by HornTube View Post
I agree completely, ANY semiconductor in a tube circuit/PSU will kill the sound. I tried semiconductors in the PSU, cathode, anode etc. Don't do it. I know there are some "gurus" out there telling us "no, no, you will not hear any semiconductor nastiness with my CCS" oh please...
what a sweeping statement, care to explain as to why?
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Old 11th September 2012, 03:13 AM   #86
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Cool it guys, note that the next person who attempts to circumvent the auto-censor will get points. Keep the posts respectful in tone or this thread has breathed its last.
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Old 16th October 2012, 02:12 AM   #87
Pano is online now Pano  United States
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I've been using LED bias with good results, but was wondering if NFB could be added there as it is with resistors. Apparently it can be, reading posts 62 & 63.

So if one wanted to add NFB at the cathode as shown in Fig. 1 (classic), it can be done as shown in Fig. 2, right? Just use a low value resistor below the LED.
(Yes, I left out a few parts)
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Old 16th October 2012, 02:17 AM   #88
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Quote:
Originally Posted by Pano View Post
So if one wanted to add NFB at the cathode as shown in Fig. 1 (classic), it can be done as shown in Fig. 2, right? Just use a low value resistor below the LED.
Right.
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Old 16th October 2012, 02:44 AM   #89
Bigun is offline Bigun  Canada
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Quote:
Originally Posted by Pano View Post
Just use a low value resistor below the LED.
(Yes, I left out a few parts)
Is one of the parts you left out a capacitor ? just wondering if without a bypass capacitor you are now going to have a.c. across the diode. And we know what that means...
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Old 16th October 2012, 02:54 AM   #90
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Quote:
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Is one of the parts you left out a capacitor ? just wondering if without a bypass capacitor you are now going to have a.c. across the diode. And we know what that means...
That means almost nothing, look at curves for LED on working cathode currents. If still worries, provide some additional current through resistor from B+.
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