This is repetition, but to be clear: the power supply ripple in the stock design is sufficiently low that it is not present in the output above the broadband output noise of the op amp itself. There will no no audible hum or buzz, just a hiss sound at high volumes. Decreasing the ripple further by increasing capacitance / adding filter stages serves no useful purpose - if you hear hum at the VSPS output it is not from power line noise on the op amp power pins - it is being picked up from other places. Hum in these circuits is the result of noise pickup, shielding, layout, or grounding errors, not excess ripple on the power supply rails.
RJM, I understand what you say, but also because I read from the beginning "all" from the beginning the post twice.
The issue as I mentioned preamplifier built maybe I've done something wrong and if you have an audible Humm with half volume. and disappeared with the addition of RCR filter box PSU.
I do not realize what has been the error.
Maybe a faulty bridge rectifier or other component. Later I will try to replace the bridges or filter capacitors on the plate, of course removing the filter RC R. Regards, Joseph.
Anyway, I congratulate you on the result of this preamplifier. Is very good .
The issue as I mentioned preamplifier built maybe I've done something wrong and if you have an audible Humm with half volume. and disappeared with the addition of RCR filter box PSU.
I do not realize what has been the error.
Maybe a faulty bridge rectifier or other component. Later I will try to replace the bridges or filter capacitors on the plate, of course removing the filter RC R. Regards, Joseph.
Anyway, I congratulate you on the result of this preamplifier. Is very good .
It's likely that the ripple on the V++ and V-- "leaked" into the output because of poor layout or shielding. So by removing the ripple on the V++ V-- by increasing the filtering, the ripple on the output was removed also.
This is like solving a hum problem by switching to batteries: no hum in the power supply, no hum in the output. Problem solved. But it isn't addressing the real cause, which is poor layout/shielding.
This is like solving a hum problem by switching to batteries: no hum in the power supply, no hum in the output. Problem solved. But it isn't addressing the real cause, which is poor layout/shielding.
Hello. RJM agree that there is something wrong, and I have calmed "fever but have not cured the disease."
Show a picture where you see only the ground wiring and connections.
I wonder where I made mistake; where is the ground loop.
Clarify that the entrance and exit of the plates have not drawn CONNECTION not to confuse, but the masses are isolated and out of the chassis.
Greetings and I hope I can help.
Anyway, it sounds spectacular, even just calming the "fever" with RCR filter in the PSU, but I want to do things right, as correspond.
Regards.
Show a picture where you see only the ground wiring and connections.
I wonder where I made mistake; where is the ground loop.
Clarify that the entrance and exit of the plates have not drawn CONNECTION not to confuse, but the masses are isolated and out of the chassis.
Greetings and I hope I can help.
Anyway, it sounds spectacular, even just calming the "fever" with RCR filter in the PSU, but I want to do things right, as correspond.
Regards.
Attachments
It's not a trick. It's basic. The chassis is the enclosing screen. It is there to prevent interference affecting the "internal" circuits.
But the Chassis of ClassI equipment must be connected to PE.
If one has exposed conductive parts, then those should be connected to the protected chassis. There is no rule that says the "internal" circuits must, or need to, be connected to the enclosing screen/chassis.
But the Chassis of ClassI equipment must be connected to PE.
If one has exposed conductive parts, then those should be connected to the protected chassis. There is no rule that says the "internal" circuits must, or need to, be connected to the enclosing screen/chassis.
AndrewT, my English is not very good and so sometimes I do not interpret some things.
For example "But the Chassis of classi equipment must be connected to PE" and "There is no rule says That the" internal "must circuits, or need to, be connected to the enclosing screen / chassis."
I have no doubt that the armed've made some mistakes that lead to hear a Hummm.
This has gone so adding a filter on the PSU RCR as disconnecting the end of the umbilical cord mesh on the side of the preamplifier.
No foundation because I am an "owner" of circuits with very little working knowledge of them. Greetings and please aclarame things not understood. Joseph.
For example "But the Chassis of classi equipment must be connected to PE" and "There is no rule says That the" internal "must circuits, or need to, be connected to the enclosing screen / chassis."
I have no doubt that the armed've made some mistakes that lead to hear a Hummm.
This has gone so adding a filter on the PSU RCR as disconnecting the end of the umbilical cord mesh on the side of the preamplifier.
No foundation because I am an "owner" of circuits with very little working knowledge of them. Greetings and please aclarame things not understood. Joseph.
Not sure if I follow. Are you saying the way ALPUY drew it was formally correct, or the way I drew it?
I would have expected that the earthed chassis should be contiguous around the whole phono stage, but in practice the two box build seems to be less prone to problems when the amplifier chassis is not earthed but connected to circuit common and the TT ground. The power supply chassis is earthed but left disconnected from circuit common.
I would have expected that the earthed chassis should be contiguous around the whole phono stage, but in practice the two box build seems to be less prone to problems when the amplifier chassis is not earthed but connected to circuit common and the TT ground. The power supply chassis is earthed but left disconnected from circuit common.
Bibio thanks, I have checked the wiring turntable. Apparently the earth plate and arm are correct. I have the idea of changing the turntable cable for this.
Thank you.
Technics SL 1200 1210 Audio Phono Cable Lead Protex Black Neutrik Van Damme 1 2M | eBay
Thank you.
Technics SL 1200 1210 Audio Phono Cable Lead Protex Black Neutrik Van Damme 1 2M | eBay
dont waste your money on new leads is my answer.
get a multimeter and disconnect your cartridge tags taking care not to snap them off the wires (they are delicate, very delicate). next take a DMM and check each wire for continuity especially tonearm tube and the earth cable. if there is no continuity between the tube and the end of the earth cable then that's more than likely where your hum is coming from. next check between each cartridge tag and the phono connector appropriate contacts. DO NOT TRY AND TAKE A READING WITH THE CARTRIDGE ATTACHED TO THE TAGS.
if all works out then look for a PE (not earth) connected to the bottom of the tonearm if there is one then disconnect and try that.
if all above is fine and correct then start looking at the electronics side.
if the turnatble is an AC motor type and a moving magnet cartridge then it could be the actual cartridge picking up the mains hum and this will be evident as the more you swing the arm towards the centre of the platter the more hum you will pick up.
get a multimeter and disconnect your cartridge tags taking care not to snap them off the wires (they are delicate, very delicate). next take a DMM and check each wire for continuity especially tonearm tube and the earth cable. if there is no continuity between the tube and the end of the earth cable then that's more than likely where your hum is coming from. next check between each cartridge tag and the phono connector appropriate contacts. DO NOT TRY AND TAKE A READING WITH THE CARTRIDGE ATTACHED TO THE TAGS.
if all works out then look for a PE (not earth) connected to the bottom of the tonearm if there is one then disconnect and try that.
if all above is fine and correct then start looking at the electronics side.
if the turnatble is an AC motor type and a moving magnet cartridge then it could be the actual cartridge picking up the mains hum and this will be evident as the more you swing the arm towards the centre of the platter the more hum you will pick up.
Has anyone tried using something like the Emotiva control freak between the VSPS and the power amp? I'm considering this as a volume control vs. building it into the VSPS itself. But also considering building a true line-stage with a proper buffer...
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A 10k stereo potentiometer, with captive cables, and a custom formed case. Ok, but it's only $40 so the price blunts any serious criticism. You don't need to ask if anyone has tried it, it is a simple volume control just like any other.
I recommend instead putting a 10k volume control in the VSPS and using a couple of b-board buffers (or whatever) to buffer the output. You might also add some line inputs, a input selector switch, and a mute switch while you go about it. Voila! Preamplifier!
I recommend instead putting a 10k volume control in the VSPS and using a couple of b-board buffers (or whatever) to buffer the output. You might also add some line inputs, a input selector switch, and a mute switch while you go about it. Voila! Preamplifier!
Indeed. I'm considering the amb sigma 24 line stage so I can also take both se and balanced inputs and output both to balanced to my ncores. Do you think there would be any issue powering them from the same psu? I'd have the rectifiers feed his sigma 25 psu ahead of the line stage but they don't draw all that much current (i think 25ma per channel) so I'm guessing its OK.