How is 30 V pk-pk 30 W?

28.125W, my bad Mr. Literal.

Quit mixing subscripts.

Not sure I like your attitude.

 

Wrong again.

Your failing to use the most basic of things, proper subscripts. I didn't even do the calculation because of that failure. Rest assured, I would have IF you had properly used the subscripts.

28.125W is not correct either.

 

subscripts

What subscripts? Instead of being an a**hole for the sake of it, how bout being helpful.

28.125W is not correct either.

How so? It says right on the screen. 15v phase peak across 8 ohms = 1.875A or 28.125W. Ohms law.
Although I am a bit confused on why the displayed dissipation isn't accounting for both phases, I expected double.

 

I see nothing when I search LTspice and subscript into google.
If you mean spice directive I'm using
.OPTIONS plotwinsize=0
.OPTIONS numdgt=7.
.four 1khz 9 i(r30)

 

Instead of being an a**hole for the sake of it, how bout being helpful.

You are in the back of a very long line of those who called me that. Now that you asked for help on this specific item, here goes:

Since the beginning, just the letter indicates rms when talking alternating waves. If your using pk or pk-pk, your answer must have that subscript.

Therefore, 15V pk^2 / 8 ohms = 28.125 W pk.

15 volts peak = 10.605 V. 10.605V^2 / 8 ohms = 14.058 W roughly.

The option you are required to use is your brain.

You need to compare like kinds. You want to enter in a certain marketplace but you don't want to produce a document that people can compare your design with those currently available to make a good choice. Like I said ... good luck with your future endeavors.

Your document would whet their appetite to want to hear your design.

You got a winner when I compared the specifications. It's always nice to compare apples to oranges.

 

Since the beginning, just the letter indicates rms when talking alternating waves. If your using pk or pk-pk, your answer must have that subscript.

Therefore, 15V pk^2 / 8 ohms = 28.125 W pk.

15 volts peak = 10.605 V. 10.605V^2 / 8 ohms = 14.058 W roughly.

The option you are required to use is your brain.

I have a difficult time understanding the way you speak, I'm going to assume english is not your first language.
I see what you're saying though.
My understanding is that 30v p-p or 10.6v rms, however you want to spin it, is sufficient to drive most 8 ohm speakers very loudly. If I'm wrong let me know.

 

There is 28.125W of power being dissipated into the 8 ohm load that I've shown above, therefore the amplifier is outputting 28.125W of power.

There are 28.125 Watts peak delivered to the load, NOT 28.125 Watts.

English is my primary language and since you have no location listed, I don't have a clue where you reside nor what you consider your primary language.

I am not arguing 14.058 Watts is not loud, on the contrary, it is loud. However, if you bothered to open the satirical specification sheet I posted, you will see what that amplifier can do and what the customer who gets it repaired wants in returned to do.

If you want to succeed, you need to speak in a manner that people can do an honest comparison of your claims to equipment, from the past, or contemporary equipment.

You may want to review the eBooks here to brush up.

 

There are 28.125 Watts peak delivered to the load, NOT 28.125 Watts.

Yeah I get it now, updated my previous post. I wasn't sure how people classified output power exactly, it's never really been an point of interest for me.

However, if you bothered to open the satirical specification sheet I posted, you will see what that amplifier can do and what the customer who gets it repaired wants in returned to do

I did read the spec sheet. I don't understand why any amplifier needs to pump out that much power. What uses that much power, ribbons maybe?

Here's my same design putting out 30v p-p into 2 ohms

As expected the distortion barely moves. There's some harmonics starting to peak out but the design is not optimized at all so I can probably iron those out, not that it would matter, it's still below 0.000000%.

 

8.125W, my bad Mr. Literal.

It's not being literal, it's being accurate.
You are welcome to you own opinion, but not your own facts.

Not sure I like your attitude.

You seem to be the one with the crappy arrogant attitude.

 

Anyway I gave a speaker amp more thought and this is the result
30vp-p into 8 ohms or about 30W.

The FFT plot in post #57 doesn't seem to square with those figures. The peak is at 0dB.

 

I challenge you to find anything that approaches that performance anywhere at that power level, or at any power level.

How about this?

This compares favourably with your post #57 plot. A ~20dB lower noise floor. As you'll appreciate, the circuit is confidential .

 

It's not being literal, it's being accurate.
You are welcome to you own opinion, but not your own facts.

I said it was "about" 30W. This implies not exactly 30W. The difference was not big enough for me to care.

You seem to be the one with the crappy arrogant attitude.

You seem to be imagining things.

This compares favourably with your post #57 plot. A ~20dB lower noise floor. As you'll appreciate, the circuit is confidential .

Very nice. Respect.

 

The FFT plot in post #57 doesn't seem to square with those figures. The peak is at 0dB.

Seems right to me. It was working in unity @ 30vp-p. I only whipped up that design for a quick demonstration, haven't managed to get it stable @ 30x gain yet, it's far from being optimized. It's designed to cancel its own distortion so I expect barely any, if any change in distortion when get it functioning @ 30x gain.
Yours is less than 0db so I assume it is also being used as a power buffer. What are the signal and load conditions for the test?

 

What are the signal and load conditions for the test?

1W peak in a 1Ω load.
Here's the FFT for 60V pk-pk and 8Ω load :

 

Well that's kind of apples and oranges. 1W into 1 ohm is 1v, 28 times less power than in post #57. The noise floor of my circuit goes down with decreasing power as demonstrated, but I guess the terms of my challenge were technically "at any power level" although I kind of meant it as rhetorical. My circuit is unstable into 1 ohm and the circuit is far too complex for me to bother solving that now so touche

 

Here's the FFT for 60V pk-pk and 8Ω load :

Touche again, very nice.

 

Yeah my design as is starts getting messy @ 60v p-p. Would need think more carefully about optimizations in order to get your performance without resorting to using global NFB. Very nice indeed

 

Alright, here's my best shot without redesigning the output stage or using Gnfb. Device noise in the output stage is preventing me from going any lower in noise floor.
60v p-p into 8 ohms

Noisefloor is -184db so around 10db off from yours. it's difficult to see your exact harmonics but by using a ruler to determine, you have a handful of harmonics within the audio range poking out between around -175db and -185db, and around -160db at higher frequencies. Mine is only barely better within the audio frequency range as I do have 2nd and third harmonic almost touching -180db but higher frequency performance is much better.
In any case, thanks for the challenge, I learned a few things

 

Here is your competition ... Or shall I say, just one opinion ... https://www.themasterswitch.com/best-stereo-amplifiers

On edit ... For the low sum of $57000, you could own this ... http://dandagostino.com/products/momentum-integrated.php. In the box you get a pair of white lifting gloves.

 

On edit ... For the low sum of $57000, you could own this ... http://dandagostino.com/products/momentum-integrated.php. In the box you get a pair of white lifting gloves.

How could you ever find speakers worthy of that?!