Agree with Zigzag 100%
Also keep in mind the resolution of your actual test rig. It’s not an audio precision.
Try to get get all your equipment to test-110dBV as best as possible as a target. Try to get the noise floor grass to be in the 120-130dBV range.
Once you get there, accept all the spikes in grass as “I don’t know what it is” because your setup can’t resolve that. Unless you want to spend a few $K.
Also keep in mind the resolution of your actual test rig. It’s not an audio precision.
Try to get get all your equipment to test-110dBV as best as possible as a target. Try to get the noise floor grass to be in the 120-130dBV range.
Once you get there, accept all the spikes in grass as “I don’t know what it is” because your setup can’t resolve that. Unless you want to spend a few $K.
So the time and care is taken to generate a perfect sinewave and then they completely flatten it to a straight line. 😆
Do not you think thats a bit misleading to make people believe amplifier power supplies can just handle line distortion?!!?
rschmitt100, no.
It think it has been well demonstrated that:
1. Conducted Line noise along with around 5% harmonic distortion can be expected due to modern electronic loads.
2. Commercial line filters as a general rule have little effect below 20KHz due to size limitations (post 10).
3. Proper power supply design and amplifier design with good PSRR will obviate any influence of line noise.
4. Ground loops suck.
This still leaves me with my second issue which is that I see extremely high (in relative terms) distortion when using an in-computer sound card generating an FFT of an external oscillator which is known to present a low noise, low distortion signal.
When using the same oscillator with a USB system (E-MU0404) the distortion is as expected.
I can expect an in system sound card to have a higher noise floor due to switcher noise, however I fail to see how it would produce higher distortion when in loop-back is shows very low distortion. (approximately 30dBfs difference in 2nd H).
It think it has been well demonstrated that:
1. Conducted Line noise along with around 5% harmonic distortion can be expected due to modern electronic loads.
2. Commercial line filters as a general rule have little effect below 20KHz due to size limitations (post 10).
3. Proper power supply design and amplifier design with good PSRR will obviate any influence of line noise.
4. Ground loops suck.
This still leaves me with my second issue which is that I see extremely high (in relative terms) distortion when using an in-computer sound card generating an FFT of an external oscillator which is known to present a low noise, low distortion signal.
When using the same oscillator with a USB system (E-MU0404) the distortion is as expected.
I can expect an in system sound card to have a higher noise floor due to switcher noise, however I fail to see how it would produce higher distortion when in loop-back is shows very low distortion. (approximately 30dBfs difference in 2nd H).
You are using Vacuum Tube Amplifiers, Right?
They are not "Green".
That is one reason why I like them.
Go out and purchase a Gasoline Powered Electric Generator, another non-"Green" idea.
If the "Green" people in Portland are so concerned about global warming, then why can I drive over the whole Portland, Oregon Metro Area and not see:
A single Solar Panel
A single Windmill
Portland's "Green" People need to fill their properties with solar panels, and windmills.
Or stop complaining about the rest of us.
Just my Amplified Opinion.
They are not "Green".
That is one reason why I like them.
Go out and purchase a Gasoline Powered Electric Generator, another non-"Green" idea.
If the "Green" people in Portland are so concerned about global warming, then why can I drive over the whole Portland, Oregon Metro Area and not see:
A single Solar Panel
A single Windmill
Portland's "Green" People need to fill their properties with solar panels, and windmills.
Or stop complaining about the rest of us.
Just my Amplified Opinion.
You people are dodging my point. Eventually you will understand that there is more to it than just measurements.
If you want to measure everything and intereperet it all as numbers, you will be disappointed, your ears will be disappointed too, you dont hear music through numbers, you hear music in an analog fashion!!! There is nothing more correct than that statement! lul
That is the problem with digital these days, and its very easy to notice.
If you want to measure everything and intereperet it all as numbers, you will be disappointed, your ears will be disappointed too, you dont hear music through numbers, you hear music in an analog fashion!!! There is nothing more correct than that statement! lul
That is the problem with digital these days, and its very easy to notice.
Designing a tube amplifier consists of using formulae, plots and math to calculate bias points.
Measurements confirm the operation of the amplifier, as tube specifications are "recommendations" not absolutes.
Listening tests confirm the measurements validated the design.
I am listening to Edie Brickell, Steve Martin and The Steep Canyon Rangers.
I saw the Steep Canyon Rangers live at the Paramount in Bristol TN last night.
I like what I hear from this amp.
Measurements confirm the operation of the amplifier, as tube specifications are "recommendations" not absolutes.
Listening tests confirm the measurements validated the design.
I am listening to Edie Brickell, Steve Martin and The Steep Canyon Rangers.
I saw the Steep Canyon Rangers live at the Paramount in Bristol TN last night.
I like what I hear from this amp.
Sure, when optimizing materials to have them work at desired gain, distortion levels and wattages, there is a place for math and calculations.
Its one way to mitigate losses.
You can quantitatively and qualitatively evaluate and improve systems of any type.
That said, amplifier listening is like a rehearsal or play. practice makes perfect.
Concerts and jam sessions are like sex and drugs, where emotions and passions are flowing at a very high level.
Its not too many times Ive experienced great music, but a several times it was with friends, in nature, and in very old concert halls and churches. Its something that happens in the moment. It is the something thats missing. I found analog class a, germanium and tube amplifiers imitate those feelings.
And isolation transformers and ps audio power dodads dont.
Its one way to mitigate losses.
You can quantitatively and qualitatively evaluate and improve systems of any type.
That said, amplifier listening is like a rehearsal or play. practice makes perfect.
Concerts and jam sessions are like sex and drugs, where emotions and passions are flowing at a very high level.
Its not too many times Ive experienced great music, but a several times it was with friends, in nature, and in very old concert halls and churches. Its something that happens in the moment. It is the something thats missing. I found analog class a, germanium and tube amplifiers imitate those feelings.
And isolation transformers and ps audio power dodads dont.
A computer Has a Switching Power Supply (for the computer's micro processors, clocks, and sound cards, etc.).
Switching interference, common mode, and differential mode can get out of any conductors: power cord, monitor cable, keyboard cable, Mouse cable, LAN cable, and sound card signal cables in & out.; etc.
And, the same Switching Power Supply interference can be Magnetically and Capacitively radiated too.
A wireless Mouse and a wireless keyboard create the other kind of interference . . . Radiated.
EMI - A regulation that computers and other electronic devices must pass.
Those high amplitude level regulations, are high so that we do not have to pay $1,000 of dollars extra to make them pass.
EMI regulations do not guarantee that . . . EMC will occur.
What is EMC?
EMC = Electro Magnetic Compatibility . . . the biggest Oxymoron of the last few decades.
Interoperability is another oxymoron.
It means all intentional radiators and intentional receivers will all operate in the same space, all on at once.
Bluetooth, wireless LAN, wireless printers, wireless thermostats, digital TV transmitters, cell phones, wireless home phones, electronics in stoves, dishwashers, microwave ovens, LED lighting, FM stations, AM stations, US Navy 1.5 Megawatt transmitters, home welders, electric car chargers, etc.
That is the price we pay for "convenience".
Switching interference, common mode, and differential mode can get out of any conductors: power cord, monitor cable, keyboard cable, Mouse cable, LAN cable, and sound card signal cables in & out.; etc.
And, the same Switching Power Supply interference can be Magnetically and Capacitively radiated too.
A wireless Mouse and a wireless keyboard create the other kind of interference . . . Radiated.
EMI - A regulation that computers and other electronic devices must pass.
Those high amplitude level regulations, are high so that we do not have to pay $1,000 of dollars extra to make them pass.
EMI regulations do not guarantee that . . . EMC will occur.
What is EMC?
EMC = Electro Magnetic Compatibility . . . the biggest Oxymoron of the last few decades.
Interoperability is another oxymoron.
It means all intentional radiators and intentional receivers will all operate in the same space, all on at once.
Bluetooth, wireless LAN, wireless printers, wireless thermostats, digital TV transmitters, cell phones, wireless home phones, electronics in stoves, dishwashers, microwave ovens, LED lighting, FM stations, AM stations, US Navy 1.5 Megawatt transmitters, home welders, electric car chargers, etc.
That is the price we pay for "convenience".
When it comes to Analog Ears, that is true.
But every ear has A/D convertors.
The ear sends Pulses to your brain for 'digital' analysis.
And, our brains are good analyzers.
Just my opinion
But every ear has A/D convertors.
The ear sends Pulses to your brain for 'digital' analysis.
And, our brains are good analyzers.
Just my opinion
Isn't live music the ultimate reference? Emotions aside, it is what we strive to recreate.
I have always enjoyed live music, whether it is a large concert of just a bunch of buddies with banjos, guitars, etc around a fire pit singing Stanton Station and passing around a quart of clear stuff. Yea, and we can't sing for S*&#t.
I have always enjoyed live music, whether it is a large concert of just a bunch of buddies with banjos, guitars, etc around a fire pit singing Stanton Station and passing around a quart of clear stuff. Yea, and we can't sing for S*&#t.
Live music, choir, instruments are reference if well played. There is nothing digital or analog in those settings, just sheer human will and beauty. If our brains were digital we'd be like china. Suicidal factory workers, constantly at war, always in debt, no way out, and ruined environments. Thats how they run the show there, and I will always cut off that damn tv, and work outside and improve things. That is how I am, that is how others should be. No way around it, unless you want things more convoluted and difficult.
Yeah, I cannot sing or play instruments either, but my sister CAN sing, I do my best to make amplifiers and speakers sing in that same sort of tune.
The oscilloscope will only get you within a set of parameters, but harmonizing amps and speakers takes practice, and clever solutions.
For all you guys looking to fix the distortion, batteries are probably the way to go. Its very green to run your amplifier off of 2 big 12v batteries, being charged by 2 panels all the time.
I have my bias set low, for an f5 at 40 watts, still sounds good at 20 watts bias too. Its a compromise I found works.
Just be careful, use some nice heavy duty blocking diodes for charging, use appropriate voltage panels. Wire it up permenaentely, or have a way to pass the wires through without problem.
Its the one solution we all have accessible. It checks the green box, the grid distortion box, its a general upgrade honestly, and it can be as cheap as having a toroidal transformer and large capacitor bank.
I paid 50 dollars for used 250w panels, it would take one of those to run it all the time, and then its just a matter of a didoe, a battery (long tractor batteries are cheap and last a long time).
SO yeah, that is my solution. Its definetly not propeur
Yeah, I cannot sing or play instruments either, but my sister CAN sing, I do my best to make amplifiers and speakers sing in that same sort of tune.
The oscilloscope will only get you within a set of parameters, but harmonizing amps and speakers takes practice, and clever solutions.
For all you guys looking to fix the distortion, batteries are probably the way to go. Its very green to run your amplifier off of 2 big 12v batteries, being charged by 2 panels all the time.
I have my bias set low, for an f5 at 40 watts, still sounds good at 20 watts bias too. Its a compromise I found works.
Just be careful, use some nice heavy duty blocking diodes for charging, use appropriate voltage panels. Wire it up permenaentely, or have a way to pass the wires through without problem.
Its the one solution we all have accessible. It checks the green box, the grid distortion box, its a general upgrade honestly, and it can be as cheap as having a toroidal transformer and large capacitor bank.
I paid 50 dollars for used 250w panels, it would take one of those to run it all the time, and then its just a matter of a didoe, a battery (long tractor batteries are cheap and last a long time).
SO yeah, that is my solution. Its definetly not propeur
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There is also the once you know it’s there effect! Once you hear or see something that you never did before it just slaps you in the face! Do yourself a favor and don’t worry about the little stuff and just enjoy what you have unless it is so bad that a deaf dog could hear it! Take care of the obvious easy stuff like ground loops and put EMI/RF filters on the lines and enjoy. Just the way I look at it. I’d rather enjoy than drive myself crazier than the world makes me as is.
How would DC power have distortion? If noise and garbage were somehow "leaking" through it would be immediately visible and measurable. My next test equipment purchase is going to be a HP 403 (or similar) AC volt meter. I never understood the point of these meters until a friend of mine explained it. They have a bandwidth of 10Mhz and use thermal conversion to measure the AC voltage. So harmonics and all are measured. Pretty handy if you want to look at power supply noise and ripple. Even good for switching supplies.
The whole dc power supply has its own characteristics. If you have for example two 50,000uf capacitor banks which should be considered sufficient, and change the diodes to 400a diodes or change the capacitor brands from shanglei to triads, or change preload resistors to wire wound or solid state you will hear the difference. Because all of it is tuned, even if you cannot measure its distortion. Best approach is hardiest parts.
The differences are losses and improvements in responsivity, like current delivery, transconduction on the silicon diode junctions, and resistances affecting frequencies, responding, and causing an effect on the signal transistors and output transistors of your amplifier.
I'm in the camp where if you dont start with high quality parts, dont bother measuring and tweaking.
Youll be bothered to measure if you perceive deficiency in your system. Others do their due diligence too. If its a well known circuit and you have ok parts, then there is no need to measure. The goal of electronics building is for it all to be very repeatable, ironically in the real world it is not.
The differences are losses and improvements in responsivity, like current delivery, transconduction on the silicon diode junctions, and resistances affecting frequencies, responding, and causing an effect on the signal transistors and output transistors of your amplifier.
I'm in the camp where if you dont start with high quality parts, dont bother measuring and tweaking.
Youll be bothered to measure if you perceive deficiency in your system. Others do their due diligence too. If its a well known circuit and you have ok parts, then there is no need to measure. The goal of electronics building is for it all to be very repeatable, ironically in the real world it is not.