Thank you for sharing your knowledge about mains. Here in the USA, it varies from 120VAC: where I live is 125 to sometimes 127VAC. Having equipment designed for 115VAC makes me concerned about life expectancy of the trannies, so much so been mulling over in the back of my head for months how to add resistors or regulators in a clean and neat manner. Have even considered using regulator valves, but require more space than solid state, plus, require modifying the circuit, as I understand only can regulate DC. Cheers, Adriel
@@adrielrowley if the gear is modern it will most likely be designed to cope with a wide range of mains voltages. Tubes in particular are very flexible as to what their operating voltages are. So long as you are within 10% of what the amp was designed for you should be fine - IF the gear was properly designed. However it can become a problem with much older electronics that were designed for 110vac, in that case you can run it on a variac and dial down the voltage or bring it to a certified technician and get them to upgrade the applicable components. In particular the filter capacitors.
@@tubelab194, thank you so very much for the reply! 😁 The console uses an EZ81, rather not push it to the limit since be running long periods, NLA, and expensive if can find one. The M-100 has a dropping resistor from the factory, so that one is easy. Are you saying a rheostat rather then a dropping resistor? I am the technician, certified technicians no longer exist, at least in the States it seems. I have a healthy respect for electricity, both from experiencing paternal great uncle's shocking machine using a telephone generator (made for teaching his daughters about electricity) and when 10 installing a ceiling fan doing a final inspection thinking was being careful, which threw me off of the ladder, thankfully without injury (bio mother wouldn't have cared). But, about a month ago got zapped by an ignition coil, thankfully despite just checking the carburetor, remembered to keep my hand behind me. Because teaching myself, why appreciate folks like this channel sharing information. 😃 The console needs all 'lytics and waxies to be replaced with quality PP caps. The amplifier carbons are way out so need replacing, radio also has a few. I been spending months on researching inductance's impact on RF circuits, finding nothing, so have to stick carbons (with limited values now no longer manufactured) or non-inductive resistors in the receiver. Once have her all sorted, then will be interesting tuning the cans without any instructions or schematics. But, challenges are fun. Cheers, Adriel
@@adrielrowley a variac is a mains voltage variable transformer designed to plug in between your wall plug and equipment, modern ones (don't buy a vintage one they aren't up to modern safety build specs) are typically rared for 10A and all come with a crappy voltage meter which you should replace with a good mini digital one (lots available on AliExpress). Once installed you can dial in your mains voltage from 0v to ~140vac. Caution! Variacs have no (zero) isolation.
@@tubelab194, yes, aware they are not isolating, what an isolating transformer is for. Concerned might mean that, was saying built in, rather then having to find space internally, which is limited. Used of eBay are very expensive for someone on a fixed income of $600 a month in SSI (I am "disabled" aka Autistic), so where is a less expensive source? Say under $15 to $20? Thank you, Adriel PS Taken me months to save the $100 to electrically restore the organ, sans valves, still got a couple projects, then be her turn.
@@adrielrowley when it comes to electrical safety, never cut corners, if you need to wait till the money is available for what you need, then it is best to wait. Caution! Failing to follow proper safety procedures or cut corners with modifications and or operating equipment at excessive mains voltage can be dangerous and could potentially kill you and or start a fire. So be conservative and cautious, do your research and only follow professional advice.
@@TrueAudio "Bad Boys" are one of the most famous 6SN7's ever made. Sylvania built them from about 1942 to 1952. They are a tall elevated T plate design, with plates set back to back, bottom foil getter and waste chrome. They made 6SN7GT and 12SN7GT (6v and 12v filament). Caution! They are 1st generation 6SN7 with much lower specs than the later GTA and GTB. As a result they can't be safely played in most modern equipment. This is one big reason why we designed the Universal 6or12SN7 Kit Preamp, to not only safely play all 6SN7's ever made, but also 12v version that is still available NOS (new old stock).
@@kenwuesq noise on the AC mains can be almost anything and will vary depending on your location, time of day, what's running in your home, your neighbors, local industry etc etc. An example of this would be a large industrial machine that cycles on and off rapidly, this would create drops and surges on the mains voltage for everyone attached nearby. Or in our case we live fairly close to a submarine base and they're constantly broadcasting on specific frequencies that subs can hear under water, some of that is in the air as EMI but some probably lands on the mains wires. So it's a composite of electrical noise and interference.
I don’t think pure power sine waves matter that much for property designed power supply circuits. As long as the voltage is within the target +/- 10%, the smoothing circuit takes care of business.
@@el_arte thinking and knowing are two completely different things. In our case we know the noisy mains voltage is a problem, because we can see it on our circuits when we scope them. Even very well designed multi stage filter circuits can have a hard time eliminating all the noise present on a particularly noisy AC mains line. And yes the power supply filters take care of much of the noise, and yes you are correct a small voltage variation isn't a problem. But when you are talking about a high gain preamp circuit like a phono preamp, tape head preamp or mic preamp in which the output is 2 to 5 millivolts (1000mV = 1vrms = line voltage), now even the smallest noise from the power supply gets amplified many times making for a problem further in the circuit. A low noise mains supply will make for lower noise equipment that will most likely sound better.
@@tubelab194 We can’t agree about everything. And I said “thinking” not to be too blunt. But I admit phono preamps are susceptible. I know I have tried many power conditioners, filters and regenerators…never heard any difference, but maybe the sine on the scope looked cleaner. Amir at ASR tested several as well, and quite a few of them actually made things worse, particularly a model from PS Audio.
@@el_arte I agree placing a power conditioner "in line" with the AC mains most likely will degrade the power supply. Our development will be centred around a power station designed to generate a clean mains supply.
As I’m building my GU50 amps, I watched the transformer episode just yesterday and did check my AC voltage, which is 123VAC.
Thank you for sharing your knowledge about mains. Here in the USA, it varies from 120VAC: where I live is 125 to sometimes 127VAC. Having equipment designed for 115VAC makes me concerned about life expectancy of the trannies, so much so been mulling over in the back of my head for months how to add resistors or regulators in a clean and neat manner. Have even considered using regulator valves, but require more space than solid state, plus, require modifying the circuit, as I understand only can regulate DC.
Cheers,
Adriel
@@adrielrowley if the gear is modern it will most likely be designed to cope with a wide range of mains voltages. Tubes in particular are very flexible as to what their operating voltages are. So long as you are within 10% of what the amp was designed for you should be fine - IF the gear was properly designed. However it can become a problem with much older electronics that were designed for 110vac, in that case you can run it on a variac and dial down the voltage or bring it to a certified technician and get them to upgrade the applicable components. In particular the filter capacitors.
@@tubelab194, thank you so very much for the reply! 😁
The console uses an EZ81, rather not push it to the limit since be running long periods, NLA, and expensive if can find one. The M-100 has a dropping resistor from the factory, so that one is easy.
Are you saying a rheostat rather then a dropping resistor?
I am the technician, certified technicians no longer exist, at least in the States it seems. I have a healthy respect for electricity, both from experiencing paternal great uncle's shocking machine using a telephone generator (made for teaching his daughters about electricity) and when 10 installing a ceiling fan doing a final inspection thinking was being careful, which threw me off of the ladder, thankfully without injury (bio mother wouldn't have cared). But, about a month ago got zapped by an ignition coil, thankfully despite just checking the carburetor, remembered to keep my hand behind me.
Because teaching myself, why appreciate folks like this channel sharing information. 😃
The console needs all 'lytics and waxies to be replaced with quality PP caps. The amplifier carbons are way out so need replacing, radio also has a few. I been spending months on researching inductance's impact on RF circuits, finding nothing, so have to stick carbons (with limited values now no longer manufactured) or non-inductive resistors in the receiver.
Once have her all sorted, then will be interesting tuning the cans without any instructions or schematics. But, challenges are fun.
Cheers,
Adriel
@@adrielrowley a variac is a mains voltage variable transformer designed to plug in between your wall plug and equipment, modern ones (don't buy a vintage one they aren't up to modern safety build specs) are typically rared for 10A and all come with a crappy voltage meter which you should replace with a good mini digital one (lots available on AliExpress). Once installed you can dial in your mains voltage from 0v to ~140vac. Caution! Variacs have no (zero) isolation.
@@tubelab194, yes, aware they are not isolating, what an isolating transformer is for.
Concerned might mean that, was saying built in, rather then having to find space internally, which is limited.
Used of eBay are very expensive for someone on a fixed income of $600 a month in SSI (I am "disabled" aka Autistic), so where is a less expensive source? Say under $15 to $20?
Thank you,
Adriel
PS Taken me months to save the $100 to electrically restore the organ, sans valves, still got a couple projects, then be her turn.
@@adrielrowley when it comes to electrical safety, never cut corners, if you need to wait till the money is available for what you need, then it is best to wait. Caution! Failing to follow proper safety procedures or cut corners with modifications and or operating equipment at excessive mains voltage can be dangerous and could potentially kill you and or start a fire. So be conservative and cautious, do your research and only follow professional advice.
what is 'bad boys' ?
@@TrueAudio "Bad Boys" are one of the most famous 6SN7's ever made. Sylvania built them from about 1942 to 1952. They are a tall elevated T plate design, with plates set back to back, bottom foil getter and waste chrome. They made 6SN7GT and 12SN7GT (6v and 12v filament). Caution! They are 1st generation 6SN7 with much lower specs than the later GTA and GTB. As a result they can't be safely played in most modern equipment. This is one big reason why we designed the Universal 6or12SN7 Kit Preamp, to not only safely play all 6SN7's ever made, but also 12v version that is still available NOS (new old stock).
Can you be more specific about what to listen for when you use the word “noise”? Is it hiss? Buzz? Hum?
@@kenwuesq noise on the AC mains can be almost anything and will vary depending on your location, time of day, what's running in your home, your neighbors, local industry etc etc. An example of this would be a large industrial machine that cycles on and off rapidly, this would create drops and surges on the mains voltage for everyone attached nearby. Or in our case we live fairly close to a submarine base and they're constantly broadcasting on specific frequencies that subs can hear under water, some of that is in the air as EMI but some probably lands on the mains wires. So it's a composite of electrical noise and interference.
Noise is any unwanted interference (just to be clear even under or above normal hearing as the 2nd and 3rd harmonics are critical)...
You need a full cycle to read frequency.
@@byronwatkins2565 yup
I don’t think pure power sine waves matter that much for property designed power supply circuits. As long as the voltage is within the target +/- 10%, the smoothing circuit takes care of business.
@@el_arte thinking and knowing are two completely different things. In our case we know the noisy mains voltage is a problem, because we can see it on our circuits when we scope them. Even very well designed multi stage filter circuits can have a hard time eliminating all the noise present on a particularly noisy AC mains line. And yes the power supply filters take care of much of the noise, and yes you are correct a small voltage variation isn't a problem. But when you are talking about a high gain preamp circuit like a phono preamp, tape head preamp or mic preamp in which the output is 2 to 5 millivolts (1000mV = 1vrms = line voltage), now even the smallest noise from the power supply gets amplified many times making for a problem further in the circuit. A low noise mains supply will make for lower noise equipment that will most likely sound better.
@@tubelab194 We can’t agree about everything. And I said “thinking” not to be too blunt. But I admit phono preamps are susceptible. I know I have tried many power conditioners, filters and regenerators…never heard any difference, but maybe the sine on the scope looked cleaner. Amir at ASR tested several as well, and quite a few of them actually made things worse, particularly a model from PS Audio.
@@el_arte I agree placing a power conditioner "in line" with the AC mains most likely will degrade the power supply. Our development will be centred around a power station designed to generate a clean mains supply.
@@tubelab194 100%