Zero Feedback Impedance Amplifiers

[Brett]

Thanks for some excellent and informative posts Susan.
Congrats on the design, and don't let the baying twits ever put you off posting.

[mikeks]

Originally posted by Brett
.................don't let the baying twits ever put you off posting.

Thus spake the twit....

[PMA]

Originally posted by Susan-Parker


Phase coherance is accuratly preserved, and it is possible to hear the movement of a violinist as she/he sways about when playing.

Others might not be so tolerant of valve level distorsion but for me phase accuracy is very important, more so than for many other people perhaps.

How can you assure and evaluate the "phase accuracy"?

[Upupa Epops]

Gentleman, have you seen anytime how look signal comes through trafo ? Susan probably had build " musical instrument ", not high fidelity amp, I am sorry, I recomend to you get on the head bag with ice. " Easy to build, recomend for third world " - are you all mad ?

[till]

U pupa, this may be your experience, with czech trafos...

Susan, thanks for sharing your circuit!

[Upupa Epops]

To Till : Many so called " deutsche transformatoren" are made in Czech republic .

[Netlist]

Guys, lets keep this nice thread on topic.
You can whish each other goodnight here :
I just finished a nice bottle of Bourgogne with my dear wife.
See you tomorrow

/Hugo

[janneman]

...truste...

i gust finid a nge botlee of wife wit my trstad borgogne.,..

[Susan-Parker]

Originally posted by PMA

How can you assure and evaluate the "phase accuracy"?

Hi.

Good question.

And the answer is very simple (but not technical).

With my amplifier I can resolve a full stereo image in front of me and hear all the sounds with clarity and they are stable.

I can accuratly place the position of a sound - with a good recording I can hear the movement of the players.

I can also listen to one instrument or sound, and follow it even when it is all but hidden in amounst other louder sounds (the sound of brass cartridges hitting a marble floor within the roar of continious automatic fire for example - The Matrix, Lobby Sceen).

On Jean Michelle Jare's Concert's in China about the third track there is an auditary firework fizzing and moving from left to right and back again. My amp keeps the sound defined and I can track it constantly.

Any other amplifier I have listed to leaves a hole and everything is muddy and ill defined.

The big problem of course is that whilst we can all talk about this audio stuff we can't actually hear the result unless we build them or know someone who has one.

I built the amps in the form you see in the picture 10 years ago. Since then most people have derided my design, particually the experts - but none of those have actually listend to them.

I fully appreciate that there are a lot of very good amplifiers out there on the market and for people to build. And some will probably be considered better than mine.

However at the end it's my preferences and own hearing which is what I am comfortable with and like, and I fully accept that other people have other values and tastes.

Different strokes, etc.

Best wishes,
Susan.

===

I will reply seperatly to the other questions in the morning.

Meanwhile I thank everyone for their positive comments.

[johnnyx]

And BTW Susan, can we look forward to your line arrays in the "loudspeakers" forum?