pinkmouse said:
Chassis ground and power ground need NOT be common. In some instances that can make things worse.
Don't yell at me, I'm just the messenger.
So long thread....
" Building effectivity " of this amp is similar to his working class - very low....😀 ... Too much space for own creativity = neverending story.... 😉... ( but BB is watching you ...
)
" Building effectivity " of this amp is similar to his working class - very low....😀 ... Too much space for own creativity = neverending story.... 😉... ( but BB is watching you ...
)
rabstg said:
If you separate power ground from chassis ground then what is it connected to? Not signal ground surely...
In all the amps I have built, I have always connected the two and never had any problems.
Pavel, give us one of your circuits and we will play for months with that as well! 😉
I'm preparing that, Al... 😉 ...but space for own improvement will be there very small 😉 - it will be made by "... take it or leave it... ", all will be strictly specifed...
Hi Joey,
as Pink says
as Rab says
Do not do this
The four black wires from the cap commons and the rectifier commons form a PSU ground. DO NOT use this as a central star ground.
Form a central star ground separate from and isolated from the chassis.
If needed, run a wire from chassis ground (safety earth) to Chassis ground terminal. Leave provision to add a separation network into the chassis ground connection wire. This network can consist of any combination of the following:- resistor//shorting switch//side by side diode pair//ceramic capacitor. The switch is a ground lift switch.
Sorry this comes so late but I always seem to be off line when the big discussions happen on this thread. Something to do with all that water between us.
as Pink says
as Rab says
Do not do this
The four black wires from the cap commons and the rectifier commons form a PSU ground. DO NOT use this as a central star ground.
This can be next to the mains input socket or next to the transformer's mains connection terminal block.
Form a central star ground separate from and isolated from the chassis.
Now run a wire from PSU common to PSU ground terminal.
If needed, run a wire from chassis ground (safety earth) to Chassis ground terminal. Leave provision to add a separation network into the chassis ground connection wire. This network can consist of any combination of the following:- resistor//shorting switch//side by side diode pair//ceramic capacitor. The switch is a ground lift switch.
Sorry this comes so late but I always seem to be off line when the big discussions happen on this thread. Something to do with all that water between us.
Hi Pink,
bigger water.
Although when the ice cap melts you might be under it.
I'm safe at 310m AOD.
bigger water.
Although when the ice cap melts you might be under it.
I'm safe at 310m AOD.
To quote the Muppets
-Ocean? Ocean?
- Yes, you know... The big blue wet thing!
- Ahh
I wonder if my other 112 posts have been as enlightening...
-Ocean? Ocean?
- Yes, you know... The big blue wet thing!
- Ahh
I wonder if my other 112 posts have been as enlightening...
Any damage to shipments?
Ok, I mailed out all the kits and heat sinks.
Anyone have damage or issues?
I have 1 pair left to ship but they are paid and addressed and I "should" be DONE.
That concludes this trip to hell and back.
I am a man of my word, and I can promise if I ever do another GB of any sort it will go better. As some of you may remember the first GB on the Jan PCB's wasn't bad at all. But the stuffing parts for 2 PCB's that were Soooooo close was VERY stressful.
Now time to start constructing my own amps.
I have All my "stuff", now to just start slipping in time between work and working on the house to sell it.
I don't idolized Mr. Pass, but he has demonstrated solid knowledge. I do agree with his current grounding scheme of Earth ground tied to the chassis, and pwr ground tied to the chassis via a CL-60.
Upupa- May I ask your thoughts on earth ground and power ground?
Not to exclude other great people, but those are the two people who's ORIGINAL designs I have seen / studied and am amazed with.
Mr. Pass is a study in effective simplicity; Pavel is a study in state of the art and beauty in execution.
Ok time to stop blowing smoke up their ***** and get back to work, but man I think it is an incredible honor to sit here and read the thoughts / chat with world renowned masters of their trade.
Ok, I mailed out all the kits and heat sinks.
Anyone have damage or issues?
I have 1 pair left to ship but they are paid and addressed and I "should" be DONE.
That concludes this trip to hell and back.
I am a man of my word, and I can promise if I ever do another GB of any sort it will go better. As some of you may remember the first GB on the Jan PCB's wasn't bad at all. But the stuffing parts for 2 PCB's that were Soooooo close was VERY stressful.
Now time to start constructing my own amps.
I have All my "stuff", now to just start slipping in time between work and working on the house to sell it.
I don't idolized Mr. Pass, but he has demonstrated solid knowledge. I do agree with his current grounding scheme of Earth ground tied to the chassis, and pwr ground tied to the chassis via a CL-60.
Upupa- May I ask your thoughts on earth ground and power ground?
Not to exclude other great people, but those are the two people who's ORIGINAL designs I have seen / studied and am amazed with.
Mr. Pass is a study in effective simplicity; Pavel is a study in state of the art and beauty in execution.
Ok time to stop blowing smoke up their ***** and get back to work, but man I think it is an incredible honor to sit here and read the thoughts / chat with world renowned masters of their trade.
Troy asked:
My packages arrived fine / AOK
Thanks again for a great job. Good Luck. I hope things go well for you in the "transition".
My packages arrived fine / AOK
Thanks again for a great job. Good Luck. I hope things go well for you in the "transition".
Re: Any damage to shipments?
Whilst I share your admiration for Nelson, I have to say he probably uses that method simply because he cannot control what the punter will plug into his amps, and so has to err on the side of caution regarding ground loops and hum. We, as diyers, however, do have that control. 😉
rabstg said:
Whilst I share your admiration for Nelson, I have to say he probably uses that method simply because he cannot control what the punter will plug into his amps, and so has to err on the side of caution regarding ground loops and hum. We, as diyers, however, do have that control. 😉
Thanks for your kind words, Troy... 🙂 But about earthing / grounding ... Earthing is safety " protection " against hazardous condition inside machine, for example against loose connection of line wire, which fall at chassis. Connection of earthed chassis and " working ground " aren't neccessary and at most of cases bring problems ( ground loops ) - you can build amp " at desk top " ( which is insulated ) and it will be operate with any problems... 😉 So if you can design own amp, I'm ready to help you... 😉
Parts
Troy,
My parts kits and sinks arrived today in good shape....thank you! Those sinks will be perfect for a chip amp project I am starting soon.
What was the source for the R504...etc. output board 0R68 10W resistors? I would like to replace the Yageos I used on my first set of boards with similar ones.
Robert
Troy,
My parts kits and sinks arrived today in good shape....thank you! Those sinks will be perfect for a chip amp project I am starting soon.
What was the source for the R504...etc. output board 0R68 10W resistors? I would like to replace the Yageos I used on my first set of boards with similar ones.
Robert
Re: Parts
Robert-
Those sinks will carry a Krell KSA-50 clone just fine. If you don't feel confident with them for the Krell I will gladly refund your money.
As for the 0r68 resistors they were "stuart specials".... I have a few left, and he may have some also.
rjkdivin said:
Robert-
Those sinks will carry a Krell KSA-50 clone just fine. If you don't feel confident with them for the Krell I will gladly refund your money.
As for the 0r68 resistors they were "stuart specials".... I have a few left, and he may have some also.
Re: Re: Parts
I have some larger sinks for my Krell.....
but yours will be great for my other project. You can also see the Yageos I would like to replace on my output boards.
Would you happen to have 12 of the resistors left? And Stuart, if you are listening do you have any available?
Robert
rabstg said:
I have some larger sinks for my Krell.....
An externally hosted image should be here but it was not working when we last tested it.
but yours will be great for my other project. You can also see the Yageos I would like to replace on my output boards.
Would you happen to have 12 of the resistors left? And Stuart, if you are listening do you have any available?
Robert
"Would you happen to have 12 of the resistors left? "
Suuure, one Miillllllion dollars. EACH.
Joking. Pay shipping and they are yours for a buck...
Suuure, one Miillllllion dollars. EACH.
Joking. Pay shipping and they are yours for a buck...
I believe those or 63,000 or 68,000uF @ 50
Looks like the Steve @ Apex.jr caps. If they are he got a good deal 😉 .
I have several of those myself. I am still on the fence on wether to use those or a pair of the BrianGT pwr supply boards (1 per channel)..
Looks like the Steve @ Apex.jr caps. If they are he got a good deal 😉 .
I have several of those myself. I am still on the fence on wether to use those or a pair of the BrianGT pwr supply boards (1 per channel)..
Hi,
seeing all that capacitance for the smoothing of a pair ClassA amps prompts a question.
Starting from what we see, 6 * 60mF caps.
Is it better to have all six set up as +-180mF shared between the two channels, or to split the capacitance using two sets of bridge diodes and run just one pair of +-60mF per channel?
Less total capacitance in return for less interaction between the channels.
Has anyone compared this trade off?
Which is more likely to sound best?
seeing all that capacitance for the smoothing of a pair ClassA amps prompts a question.
Starting from what we see, 6 * 60mF caps.
Is it better to have all six set up as +-180mF shared between the two channels, or to split the capacitance using two sets of bridge diodes and run just one pair of +-60mF per channel?
Less total capacitance in return for less interaction between the channels.
Has anyone compared this trade off?
Which is more likely to sound best?
Re: Re: Parts
Hi Tony,
Have you built a KSA50 with those sinks yet? Are you planning to use two per channel. I'm not sure that one per channel will handle it. I used similar sized sinks on my second amp and they had twice the number of fins and I definitely need to run a fan.
Hi Andrew,
On my first KSA Clone I used a single 30-0-30 500vA transformer and 6x15,000uf filter caps in a CRC configuration set up like this.
On my second one I used two 28-0-28 500va transformers with 6x18,000uf per channel in a CRCRC. I have not measured them but they sound the same. I can't hear any improvement with the second one over the first.
Blessings, Terry
rabstg said:
Hi Tony,
Have you built a KSA50 with those sinks yet? Are you planning to use two per channel. I'm not sure that one per channel will handle it. I used similar sized sinks on my second amp and they had twice the number of fins and I definitely need to run a fan.
AndrewT said:
Hi Andrew,
On my first KSA Clone I used a single 30-0-30 500vA transformer and 6x15,000uf filter caps in a CRC configuration set up like this.
On my second one I used two 28-0-28 500va transformers with 6x18,000uf per channel in a CRCRC. I have not measured them but they sound the same. I can't hear any improvement with the second one over the first.
Blessings, Terry