Old Distortion Analyzer and Audio Analzyer

[walters]

For the Old Distortion Analyzer you had to "null" out the fundamental frequency how was this done?

How do i check the 2nd harmonic?

The audio Analzyers had a intermodulation analyer how do u use this please?

How do u do a Harmonic Distortion Test?

How to Measure the 2nd harmonic Distortion test?

 

[audioguru]

For the Old Distortion Analyzer you had to "null" out the fundamental frequency how was this done?

How do i check the 2nd harmonic?

The audio Analzyers had a intermodulation analyer how do u use this please?

How do u do a Harmonic Distortion Test?

How to Measure the 2nd harmonic Distortion test?

Yes. :lol: :lol:
It was lots of fun.

 

[walters]

i bet it seems hard

 

[audioguru]

Operating an old "null" distortion analyser wasn't hard, just time-consuming if you wanted to measure distortion at many frequencies. Modern FFT analysis shows nearly all distortion at a single glance.

 

[walters]

null" distortion analyser wasn't hard, just time-consuming if you wanted to measure distortion at many frequencies.

How did u have to "null" them out ?

Which harmonics did u have to null out?

How to measure the distortion?

 

[audioguru]

Walters,
You are asking questions about harmonic distortion without knowing anything about it. Try Google first before asking basic questions here.

You don't null harmonics, they are the distortion. You null the fundamental frequency.
An AC meter or 'scope showed the level of the harmonic distortion as a percentage of the level of the fundamental.

 

[walters]

You don't null harmonics, they are the distortion.

So Harmonics= Distortion?

Whats the different between Harmonics VS frequencys?

"You null the fundamental frequency"

WHy dou null the fundamental Frequency?

An AC meter or 'scope showed the level of the harmonic distortion as a percentage of the level of the fundamental.


On the Scope what does Harmonic Distortion look like?

What are good harmonic distortion VS bad harmonic distortion when view or looking on the oscilloscope please?

 

[audioguru]

Don't ask simple basic questions here, look in Google and learn it yourself.

 

[walters]

theses aren't simple basic questions

 

[audioguru]

theses aren't simple basic questions

They sure are simple basic questions. They show that you know nothing about distortion and a distortion analyser.
They show that you haven't bothered looking for the answers yourself.

You seem to be just reading the index or just looking at the pictures in a textbook without reading its articles. :cry:

 

[walters]

can u please help me out with this then because i don't know about
distortion and a distortion analyser and about harmonics and harmonic distiortion

1.) How do measure distortion?
2.) What is a Distortion Analyer?
3.) How to measure Harmonics?
4.) How to measure Harominc distortion?

What is the 2nd harmonic distortion? why is it not good ?

 

[audioguru]

Walters,
In Google I entered How To Measure Harmonic Distortion and links on the 1st page answered all your questions. Some are confusing so maybe a textbook is best.

2nd harmonic distortion is called even-harmonics distortion and usually includes all the other even-numbered harmonics in the total of its distortion. It is caused by a non-linear device passing a positive or negative part of a waveform more or less than the other, like a rectifier.

A Jimmy Hendricks "fuzz-face" circuit produces severe 2nd (and others) harmonic distortion.
An ordinary transistor without negative feedback produces 2nd (and others) harmonic distortion:

 

[walters]

Thanks for the help


"2nd harmonic distortion is called even-harmonics distortion and usually includes all the other even-numbered harmonics in the total of its distortion."

Is 2nd harmonic distortion comes from the silicon transitor or germanium transistor?

What causes the 2nd harmonic distortion?

I thought Tubes produced odd harmonics not even so tubes don't have 2nd harmonic distortion?


"It is caused by a non-linear device passing a positive or negative part of a waveform more or less than the other, like a rectifier"

This part i don't understand passing a positive or negative part of a wavefrom?

A rectifier has 2nd harmonic distortion?

A Jimmy Hendricks "fuzz-face" circuit produces severe 2nd (and others) harmonic distortion.

How and Why?

Why does negative feedback produce 2nd harmonic distortion?

"An ordinary transistor without negative feedback produces 2nd (and others) harmonic distortion"

with out negative feedback its still causes 2nd harmonic distortion Why and where? and how?

 

[_3iMaJ]

Why even bother anymore? Go to college.

 

[walters]

my college didn't or book didn't teach this stuff sorry

 

[audioguru]

Is 2nd harmonic distortion comes from the silicon transitor or germanium transistor?

Any class-A transistor or vacuum tube circuit without negative feedback causes 2nd harmonic distortion.

What causes the 2nd harmonic distortion?

I told you already and showed a distorted waveform. Look in Google.

I thought Tubes produced odd harmonics not even so tubes don't have 2nd harmonic distortion?

No. Any class-B transistor or vacuum tube circuit without negative feedback causes odd harmonics distortion. An amplifier that clips symmetrically produces odd harmonics distortion.

i don't understand

If the upper half of a waveform is amplified or reduced more or less than the lower half, then there is even-harmonics distortion because a transistor or vacuum tube is non-linear without negative feedback.

A rectifier has 2nd harmonic distortion?

That's what I said.

How and Why does a Jimmy Hendricks "fuzz-face" circuit produce severe 2nd (and others) harmonic distortion?

Because it doesn't have negative feedback and it is improperly biased so it produces severe distortion. It operates like a rectifier.

Why does negative feedback produce 2nd harmonic distortion?

You are backwards. Negative feedback reduces distortion.

 

[walters]

Thanks alot for the information and help

Quote:
A rectifier has 2nd harmonic distortion?

That's what I said.

But how does a rectifier have 2nd harmonic distortion i don't get it?

What causes the recifier to have 2nd harmonic distortion?

Quote:
How and Why does a Jimmy Hendricks "fuzz-face" circuit produce severe 2nd (and others) harmonic distortion?

Because it doesn't have negative feedback and it is improperly biased so it produces severe distortion. It operates like a rectifier.


How does the fuzz face operate like a rectifier ?

 

[audioguru]

But how does a rectifier have 2nd harmonic distortion i don't get it?

What causes the recifier to have 2nd harmonic distortion?

It passes only the upper or only the lower half of a waveform. Even harmonics are produced when the amplification or loss of the upper half and the lower half are different, caused by non-linearity.

How does the fuzz face operate like a rectifier ?

Because it doesn't have negative feedback and it is improperly biased.
Here is a sim of it playing a pure sine-wave. Notice how the lower part of the sine-wave is removed, like a rectifier:

 

[walters]

Thanks alot for the help

"Notice how the lower part of the sine-wave is removed, like a rectifier"

How does the fuzz face "Remove" the lower part like that ?

How does improperly biased circuit act like a rectifier?

If the face face had "negative feedback" would there be "more" or "less" 2nd harmonic distortion?

 

[audioguru]

"Notice how the lower part of the sine-wave is removed, like a rectifier"

How does the fuzz face "Remove" the lower part like that ?

How does improperly biased circuit act like a rectifier?

If the face face had "negative feedback" would there be "more" or "less" 2nd harmonic distortion?

Learn about how to properly bias transistors.
Negative feedback reduces distortion.