100W Ultimate Fidelity Amplifier

[olafk]

I do not know if I am asking for too much but can You repeat one square wave measurement on 8 r with small cap in parallel please ( someting like 0,47uf or similar)

Thanks

Here are the pictures (1 - 5 - 10 - 15 - 20 kHz).

regards Olaf

 

[olafk]

Sorry, forgotten - cap was 470nF.

regards

 

[borys]

Sorry, forgotten - cap was 470nF.

regards

Thank You very very much.
Amp looks rock solid construction. I am waiting for all parts arive to complete it.
Thanks again

 

[AndrewT]

post2041.
You really need to compare input signal to output signal using a dual beam or dual trace scope. (dual beam are quite rare).

 

[olafk]

post2041.
You really need to compare input signal to output signal using a dual beam or dual trace scope. (dual beam are quite rare).

The input signal is a pure exactly square wave with 0.8V approx. as shown in Fig. with 1kHz.
The differences in output are the slope with increasing frequency, and the small peaks at the corners (see picture).
What else can we see, phase shift?
I can do it again if required. The oscilloscop is for dual-measuring.

regards Olaf

 

[AndrewT]

Yes, you and we need to see the input signal to allow comparison with the output signal.

If the input has overshoot and this is mimicked in the output, but you don't show us the input, we could be mislead into thinking the amplifier is adding the overshoot.

You must be unbiased in how you present the information.

 

[olafk]

OK, you're right. I'm just a beginner. I'll get back in 20minutes.

 

[olafk]

OK, here are the new images.
I hope someone will explain what can be seen in the pictures. I can measure again, today is holiday in Germany ;-)
Compared to the original circuit, I use 220R instead 180R in CCS.

regards Olaf

 

[AndrewT]

The input has a slightly rounded corner to the squarewave and no evidence of overshoot that I can see.
The output clearly shows overshoot and slew rate.
Are your probes adjusted to show squarewaves correctly?

 

[olafk]

The input has a slightly rounded corner to the squarewave and no evidence of overshoot that I can see.
The output clearly shows overshoot and slew rate.
Are your probes adjusted to show squarewaves correctly?

This is input if Amp has no power. The peaks on input come from the amplifier.

 

[olafk]

Now I changed all 330p to 100p. Slew rate is better as expected.
(10 + 20kHz). I hope, the probes are correct, but 20cm wire.

regards

 

[apexaudio]

Now I changed all 330p to 100p. Slew rate is better as expected.
(10 + 20kHz). I hope, the probes are correct, but 20cm wire.

regards

Thank you for this measurements, result is very good.
Regards

 

[AndrewT]

This latest pic looks different from the previous input.
Have you swapped scope probes?
I ask again

Are your probes adjusted to show squarewaves correctly?

 

[olafk]

No, I did not swapped the probes. But I changed the Cap at input from 330 to 100p.
It looks like a better slew rate but a bit more overshoot. But I have no particular experience.

regards Olaf

 

[olafk]

Have you seen the input without amplifier? Looks good.
If amp is connected, input has peaks?!

reegards Olaf

 

[Denmas]

I like the Apex AX11, and this is not foreign to me because it is similar to the scheme Sansui AU217
Greetings Denmas.

 

[apexaudio]

AX11 with TO3 outputs

 

[apexaudio]

I like the Apex AX11, and this is not foreign to me because it is similar to the scheme Sansui AU217
Greetings Denmas.

Thanks for this info, yes it's same topology.
Regards

 

[PetruV]

What is the advantage of using to3 transistors

 

[AndrewT]

What have you blown up today?
To3 is more resistant to blowing up.
Maybe what you need to suit your building style: switch on and hope/pray/have faith.