Output coil on power amp...

[Christer]

Is there any theoretical reason or just any hypothesis why the coil should affect the sound? Or is it only (nothing negative intended) a subjective empirical observation?

 

[john curl]

Not that I have found.

 

[Iyremenko]

We, high enders, have found that the coil changes the sound for the worse, and we have developed ways of making the amp unconditionally stable without it.

High Enders

 

[Bob Cordell]

We, high enders, have found that the coil changes the sound for the worse, and we have developed ways of making the amp unconditionally stable without it. (at least most of us have).

Hi John,

Can you share with us, in general terms, what those ways are? I respect your need to keep some things close to the vest, but if there are a lot of "we" people doing it, there may be some aspects that are not proprietary.

Thanks,
Bob

 

[TOINO]

My way.

 

[lumanauw]

Hi, Toino,

Your attachment seems to be CFP output stage with gain. Is this output stage topology can always skip the output coil?

 

[kASD]

CFP stages are attractive if designed with intellect

Hi, Toino,

Your attachment seems to be CFP output stage with gain. Is this output stage topology can always skip the output coil?

Hi David,
Conditions apply, such as Gain factor, Phase margin, compensation involved. I have implemented various types of CFP stages which are free from oscillation, very fast recovery from clipping, virtually free from saturation no matter how hard you drive them,Full powerbandwidth exceeding 50KHz,no output coil needed.
regards
Kanwar

 

[TOINO]

Is this output stage topology can always skip the output coil?

Hi lumanauw

Certanly not!

The trick is in the C+R network on local feedback loop.
In my case I have achieved 40V/uS slew rate unconditionally stable.
10KHz square is not problem for 2uF capacitor on output, except that it triggers the
short circuit protection above a certain level.

And they are no rigging on the output squarewave with the capacitor connected.
With and without is almost the same.

 

[GK]

Is there any theoretical reason or just any hypothesis why the coil should affect the sound?

Ringing, silly.

 

[Hartono]

with music ? how ?

 

[TOINO]

Ringing, silly.

See my flag?
I have some trouble with the English, sorry…

 

[TOINO]

And yes.
Maybe that could explain why the coil affects the sound.

 

[GK]

And yes.
Maybe that could explain why the coil affects the sound.

????????????

 

[TOINO]

Well… it is just a suggestion…
The truth is that, in the scope, the squarewave signal is clean with heavy capacitive load.

 

[TOINO]

Much worse is that I don’t understand how your Avatar could stand.
Their gravity center seems too much in front…

It doesn’t suffer lumbar pains?

Besides I have some trouble reading your posts, because it is difficult to take my yes out of him…

 

[AKSA]

Toino,

Perhaps that is because any phase shift between voltage and current at the load is much reduced by the essentially resistive feedback of a CFP with gain? (I am not talking centre of gravity here!!)

This configuration would work even better if you could guarantee that the inactive device never completely switched off....

Hugh

 

[TOINO]

Toino,
This configuration would work even better if you could guarantee that the inactive device never completely switched off....
Hugh

I now AKSA, but that is another story...

 

[kASD]

Toino,
This configuration would work even better if you could guarantee that the inactive device never completely switched off....

Hugh

Just achieved in CFP,100% NO SWITCH OFF

Cheers,
Kanwar

 

[TOINO]

Just achieved in CFP,100% NO SWITCH OFF

Hi Workhorse
What are you talking about?

 

[kASD]

Hi Workhorse
What are you talking about?

NON Switching CFP Class-AB...