hum
I use BC546 for driving relay.
My System : Player<->DC B1-with shuntreg<->Gainclone 3886.
There is no hum when GC power ON and DC B1 still OFF, but after DC B1 ON and relay still OFF, i heard hum loudly.
tq
Sorry for late response.
I use BC546 for driving relay.
My System : Player<->DC B1-with shuntreg<->Gainclone 3886.
There is no hum when GC power ON and DC B1 still OFF, but after DC B1 ON and relay still OFF, i heard hum loudly.
tq
You need BC517 in case you hear any strange mechanical noises from the relay.
The solution for you is in the pages 177-178. Do that grounded cross mod and it will not interact again.
But the steady recommendation for any system from stadium PA to home, is we turn on the power amp last and we shut it down first. To turn on/off any device before it when power's on is risky anyway. So when you will do that Oenboek's mod don't forget and go on/off all the time with the power amp on just because there will be no tell tale noises.
The solution for you is in the pages 177-178. Do that grounded cross mod and it will not interact again.
But the steady recommendation for any system from stadium PA to home, is we turn on the power amp last and we shut it down first. To turn on/off any device before it when power's on is risky anyway. So when you will do that Oenboek's mod don't forget and go on/off all the time with the power amp on just because there will be no tell tale noises.
Ok, so I dropped the output impedance of the DCB1 to 470R from the 1K as the 1K was just a little too flat (the amp input impedance is 7k). While I was at at I decided to put in the 3.5ohm resistors. I measured for current and got 177mA/215mA. Any idea why this would be? I checked last night and then again this morning. The resistors are definitely 3.5 Eagle...
One side of LEDs (negative) is definitely brighter than the other now.
One side of LEDs (negative) is definitely brighter than the other now.
Disregard idiot statement above. I was still dividing by the 10ohm value. The current is ~505/614mA. It pays to be awake when you do math.
It does get a bit hot, but since the whole enclosure is the heatsink I think it will be manageable. However, I will probably drill a hole and power a fan with a wall wart since the classdaudio amp also gets quite hot with its heatsink.
That said, based on listening last night and this morning, this is the best my DCB1 has sounded. Will evaluate further tonight, but with increased current beyond 250mA, perhaps the returns aren't quite as diminished after all...
It does get a bit hot, but since the whole enclosure is the heatsink I think it will be manageable. However, I will probably drill a hole and power a fan with a wall wart since the classdaudio amp also gets quite hot with its heatsink.
That said, based on listening last night and this morning, this is the best my DCB1 has sounded. Will evaluate further tonight, but with increased current beyond 250mA, perhaps the returns aren't quite as diminished after all...
hum
Last night i try upgrade grounding system of power source (line) and suddenly everything is quite just like "coffins ".
Thanks salas,
Last night i try upgrade grounding system of power source (line) and suddenly everything is quite just like "coffins ".
Whatever. I did not experience it myself either nor it was picked up by the numerous proto testers. Something in some systems must be exaggerating it. Maybe grounding too as you say. Keep in mind the solution mod if it appears again with some other partner equipment though. Thanks for reporting.
Just want to report, that i have been runnning the dcb1 for a couple of days now since i did the grounded cross mod, and everything is fine, there are no problems to report with this mod, so if anyone is experiencing hum(buzz) when powering down the dcb1 while the poweramp is on, then as Salas say "The solution for you is in the pages 177-178" plus you get the advantage that it takes the relay out of the signal path 
Would it be too much to ask for Post #s instead of Page #s - some folks elect to have more posts per page.
Thanks,
Just want to say that I spent more time listening to the 'really-damn-hot-rod' (or maybe 'hell-rod'?) last night. It just sounds better to my ears. Much better. Although I did change the output resistors down to 470, the difference in overall clarity, smoothness, etc. was not heard in the 220R or 1k. So unless I luckily hit some sort of sweet spot, the improvement is worth the extra heat. Hope someone else gives it a go to compare.
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Just want to say that I spent more time listening to the 'really-damn-hot-rod' (or maybe 'hell-rod'?) last night. It just sounds better to my ears. Much better. Although I did change the output resistors down to 470, the difference in overall clarity, smoothness, etc. was not heard in the 220R or 1k. So unless I luckily hit some sort of sweet spot, the improvement is worth the extra heat. Hope someone else gives it a go to compare.
Glo-Rod
Just want to say that I spent more time listening to the 'really-damn-hot-rod' (or maybe 'hell-rod'?) last night. It just sounds better to my ears. Much better. Although I did change the output resistors down to 470, the difference in overall clarity, smoothness, etc. was not heard in the 220R or 1k. So unless I luckily hit some sort of sweet spot, the improvement is worth the extra heat. Hope someone else gives it a go to compare.
Its not your imagination. That is why we aimed Blue will be more ready for extreme sports users.
Its not your imagination. That is why we aimed Blue will be more ready for extreme sports users.
Ahhh.
Speaking of which, is the fact that I only have 2x4700uf - versus the 4x on the Blue Board - an issue with this mod?
There is strong PSRR and stability in the regs, filtering not an issue as such. Its some users unavoidably will want it all out and far out so its good to be able to experiment with more filtering and TO-220 diode types because there will be anti polar bear energy consumption policies most likely.
