And, of course there's this one:
http://www.diyaudio.com/forums/showthread.php?s=&postid=16083&highlight=blocking+circuit#post16083
Gabe,
It is indeed intended to fit in series with the AC supply from the wall outlet, though I must reiterate Frank's comment on safety. There is potential for danger, if not engineered properly.
In the event of DC being superimposed on the AC mains, the diode bridges allow up to about 1.8v to be developed across each capacitor network.
IMO There is no point to having a network in each mains wire leg. If more DC offset needs to be catered for, simply put more bridges in series. After all, it's the caps that are a bind - big values, high current.
My above comment only applies to fdegrove's circuit. Mlloyd1's circuit depends on an electrolytic cap's tolerance to small amounts of reverse voltage.
The effectiveness of such circuits will depend on the type of transformer. Some, such as toroids are more susceptible to DC than others.
Cheers,
http://www.diyaudio.com/forums/showthread.php?s=&postid=16083&highlight=blocking+circuit#post16083
Gabe,
It is indeed intended to fit in series with the AC supply from the wall outlet, though I must reiterate Frank's comment on safety. There is potential for danger, if not engineered properly.
In the event of DC being superimposed on the AC mains, the diode bridges allow up to about 1.8v to be developed across each capacitor network.
IMO There is no point to having a network in each mains wire leg. If more DC offset needs to be catered for, simply put more bridges in series. After all, it's the caps that are a bind - big values, high current.
My above comment only applies to fdegrove's circuit. Mlloyd1's circuit depends on an electrolytic cap's tolerance to small amounts of reverse voltage.
The effectiveness of such circuits will depend on the type of transformer. Some, such as toroids are more susceptible to DC than others.
Cheers,
Hi Frank, Peter, Gabe, and John;
Thanks! I'll take a good look at each of those circuits later after I catch up on my sleep (it's about 3am here as I type away).
It's been a long day here since my 270DX showed up and I performed major surgery on my little 6BM8. The patient survived and is going through it's paces as I bang away at the keyboard. Sam Cooke sounds just fine!
So far (after about 4 hours of continuous operation) it looks like I bought myself 9 degrees C on the cooling issue (51C/46C depending on the part of the trafo you measure - hottest near the valves) as well as some extra 'oomph'. I upped the 820r dropper ('twixt the 100uF filter caps) to a 1k2r 25W dropper and as expected the B+ climbed to just over 260V. Sonically, the effect is a greater sense of dynamics as well as a little smoother overall sound (biggest diff at this B+ is that the triode input stage is drawing a bit more current). Overall I like the changes, though it would've been nice if it'd run cooler than this (*sigh* - I probably should've splurged and got the 270FX instead).
John, I'll answer your email after I get some sleep. I just checked my email (I've been drilling, cutting, soldering, occasionally cursing, and in general working like a maniac all day on my 6BM8/ECL82). ‚Ç‚¤‚à ‚·‚Ý‚Ü‚¹‚ñ for the delay!
Thanks again everyone!
All the best,
Morse
Thanks! I'll take a good look at each of those circuits later after I catch up on my sleep (it's about 3am here as I type away).
It's been a long day here since my 270DX showed up and I performed major surgery on my little 6BM8. The patient survived and is going through it's paces as I bang away at the keyboard. Sam Cooke sounds just fine!
So far (after about 4 hours of continuous operation) it looks like I bought myself 9 degrees C on the cooling issue (51C/46C depending on the part of the trafo you measure - hottest near the valves) as well as some extra 'oomph'. I upped the 820r dropper ('twixt the 100uF filter caps) to a 1k2r 25W dropper and as expected the B+ climbed to just over 260V. Sonically, the effect is a greater sense of dynamics as well as a little smoother overall sound (biggest diff at this B+ is that the triode input stage is drawing a bit more current). Overall I like the changes, though it would've been nice if it'd run cooler than this (*sigh* - I probably should've splurged and got the 270FX instead).
John, I'll answer your email after I get some sleep. I just checked my email (I've been drilling, cutting, soldering, occasionally cursing, and in general working like a maniac all day on my 6BM8/ECL82). ‚Ç‚¤‚à ‚·‚Ý‚Ü‚¹‚ñ for the delay!
Thanks again everyone!
All the best,
Morse
Night dreaming?
Hi,
Could somebody explain to me why my amp sounds excellent at 4:00 a.m. and just ok in the daytime?
Puzzled....anyway i'm lucky here for i go to bed when most are beginning to wake up.
Now that i know how my amp behaves i wait until 2a.m. to begin my listenings....i am spoiled....it makes a REAL difference!
What i want to know if this is a subjective impression or not. Has anybody noticed?
Hi,
Could somebody explain to me why my amp sounds excellent at 4:00 a.m. and just ok in the daytime?
Puzzled....anyway i'm lucky here for i go to bed when most are beginning to wake up.
Now that i know how my amp behaves i wait until 2a.m. to begin my listenings....i am spoiled....it makes a REAL difference!
What i want to know if this is a subjective impression or not. Has anybody noticed?
I'd suspect your mains
Unless a person's physiology listens differently in the wee hours or some factor like temperature or humidity is causing a change, it seems to me the variable factor causing the change is the quality of your mains electricity. Mains quality has not been well addressed, IME, by the audio community. I've heard substantial differences in my system using various forms and combinations of passive (usually transformer based) and active mains regulation. That difference is perhaps of equal or similar magnitude to the difference you are hearing.
Unless a person's physiology listens differently in the wee hours or some factor like temperature or humidity is causing a change, it seems to me the variable factor causing the change is the quality of your mains electricity. Mains quality has not been well addressed, IME, by the audio community. I've heard substantial differences in my system using various forms and combinations of passive (usually transformer based) and active mains regulation. That difference is perhaps of equal or similar magnitude to the difference you are hearing.
Thanks for the insights, well i have just read an interesting article which may be a bit esoteric but explains my late night experiences. Here's the link in case anyone is interested:
http://www.decware.com/newsite/mainmenu.htm
Sharp senses... not really alcohol...try another
http://www.decware.com/newsite/mainmenu.htm
Sharp senses... not really alcohol...try another
I have merged these 2 similar threads.
Mains noise
What are the sources of mains noise? Doesn't every electrical component drawing electricity from the mains contribute some form of noise---and not only every component drawing electricity in my house/apartment, but every component drawing electricity from the sub-transformer feeding my house/apartment and all my neighbours' houses/apartments? And why stop at the subtransformer?
What are the sources of mains noise? Doesn't every electrical component drawing electricity from the mains contribute some form of noise---and not only every component drawing electricity in my house/apartment, but every component drawing electricity from the sub-transformer feeding my house/apartment and all my neighbours' houses/apartments? And why stop at the subtransformer?
Firstly everything contributes noise to your power distribution.
Even the actual wiring of your house /and/ the miles and miles of interconnected super-powered Antenna system which we call a "Power grid".
From a simple resistive load like a street light to your Computer or Fridge or Hot-water system...
I personally have been listening to audio for the past 3 years after 12 AM and apart from the very large drop off in ambient noise I think tiredness plays an extremely important part in making things sound 'better', I believe when you are tired you become emotionally enravelled in the music and because you /know/ everyone else is asleep you can feel completely alone with the music!!
I've been doing this for 3 years and just recently I've managed to schedule my sleeping pattern so I go to sleep at 6PM so I can wake up at 1AM in the morning, however, now that I get a full nights sleep something strange happens, I am no longer tired therefore I am no longer interested in the music!
Conclusion:
The music maybe the most perfect representation of the original performance in the world but it is all based upon EMOTIONS.
Yes I believe also that Line noise plays a good deal in sound quality, thats why I have re-designed my KT88 amp's PSU with E core trafos and heavy capacitance through the usual choke arrangement.
I wouldn't be surprised one bit that DC Battery-fed Filaments are much more stable than AC line fed filaments simply because of unregulation of the AC mains, however, I believe the 50hz 'radio-wave' operation of a filament plays a very large part in keeping it at optimatum.
Has anyone done reports on filament operation at AC and DC and does it affect way the tube works? Is there more saturation?
Would it be beneficial to run the entire amplifier and source devices off remote-controlled Generator power? Generators are becoming incredibly cheap nowdays, so why not?, As long as acoustical isolation is taken care of...?
Even the actual wiring of your house /and/ the miles and miles of interconnected super-powered Antenna system which we call a "Power grid".
From a simple resistive load like a street light to your Computer or Fridge or Hot-water system...
I personally have been listening to audio for the past 3 years after 12 AM and apart from the very large drop off in ambient noise I think tiredness plays an extremely important part in making things sound 'better', I believe when you are tired you become emotionally enravelled in the music and because you /know/ everyone else is asleep you can feel completely alone with the music!!
I've been doing this for 3 years and just recently I've managed to schedule my sleeping pattern so I go to sleep at 6PM so I can wake up at 1AM in the morning, however, now that I get a full nights sleep something strange happens, I am no longer tired therefore I am no longer interested in the music!
Conclusion:
The music maybe the most perfect representation of the original performance in the world but it is all based upon EMOTIONS.
Yes I believe also that Line noise plays a good deal in sound quality, thats why I have re-designed my KT88 amp's PSU with E core trafos and heavy capacitance through the usual choke arrangement.
I wouldn't be surprised one bit that DC Battery-fed Filaments are much more stable than AC line fed filaments simply because of unregulation of the AC mains, however, I believe the 50hz 'radio-wave' operation of a filament plays a very large part in keeping it at optimatum.
Has anyone done reports on filament operation at AC and DC and does it affect way the tube works? Is there more saturation?
Would it be beneficial to run the entire amplifier and source devices off remote-controlled Generator power? Generators are becoming incredibly cheap nowdays, so why not?, As long as acoustical isolation is taken care of...?
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