Felicia Balanced Power Conditioner Website

[audioferret]

I am constructing the Felicia described and outlined in Audiocircle.com under "The Lab". The project was designed and tested by Occam and others.

http://www.audiocircle.com/circles/v...ic.php?t=18441

I noticed a need for more detailed construction plans, so I am building a website dedicated to the project. Hopefully, it will help others.

You can follow my progress at:

http://www.geocities.com/ghaunadaur9...o/felicia.html
and
http://www.geocities.com/ghaunadaur9.../felicia2.html

I will clean up the website after I finish the project, but will add pages as I complete each stage.

Enjoy! (And stop me if I am doing something that will electrocute myself!)

[ozone_stink]

I've been waiting for somebody to do this!!

Thank you!! I hope you don't light your hair on fire!!

Cheers,

-Matt.

[AndrewT]

Hi,
I have had a look at the audio circle link.
Why are the two 110Vac primaries connected in series from the 110Vac mains outlet?

Would it be easier to connect a 110Vac primary to 110Vac mains outlet?

I can see that the second transformer needs dual primaries to form the balanced output.

What is the purpose of reducing the intermediate coupling stage down to 12Vac? You are using 400V caps.

[audioferret]

Yes, the site is now annotated to show that the first transformer was wired incorrectly. I will post new photos soon.

http://www.geocities.com/ghaunadaur9.../felicia3.html

The filter in the middle simply works. The lower voltage "might" be used to keep the stress on the capacitors smaller, thus making their job easier with more headroom. (I am guessing here.)

This thing already sounds excellent!

[audioferret]

I have finished the project and posted my results to my web page.

Now, I need to refine it. I have a list of comments from Occam that I need to add (such as crediting the original designer, John Rish). I also need to add an index page overview and a pictoral parts list. Last, I will add navigation buttons to make surfing easier. For now, just change the number after 'felicia' from 1-8 in your HTML browser.

I need input from other readers as well, particularly ones who are not familiar with this kind of project. While this is not a project for the uninitiated, this is something that can be pretty tricky. (I learned the hard way)

As time goes by, I hope this web site serves as a good reference to help others.

http://www.geocities.com/ghaunadaur9.../felicia4.html
http://www.geocities.com/ghaunadaur9.../felicia5.html
http://www.geocities.com/ghaunadaur9.../felicia6.html
http://www.geocities.com/ghaunadaur9.../felicia7.html
http://www.geocities.com/ghaunadaur9.../felicia8.html

[ctviggen]

You could probably use voltages other than 12V. A 10:1 transformer is probably just easy to find and relatively inexpensive. The idea is to get rid of common mode noise.

[pmkap]

Originally posted by ctviggen
You could probably use voltages other than 12V. A 10:1 transformer is probably just easy to find and relatively inexpensive. The idea is to get rid of common mode noise.

Absolutely! The higher the voltage on the secondaries, the lower (all things being equal) the losses. The choices of the transformers was dictated by the availability of inexpensive, surplus, dual bobbin transformers. Dual bobbin transformers were chosen for their low bandwidth and minimal capacitive coupling between primary and secondary. Originally, 175va Signal A41 transformers were specified as they were available from BGMicro for $10ea. When they became unobtainium, the more expensive transformers from MPJA were suggested.
The purpose of those caps accross the transformers secondaries is to convert differential (transverse) noise to common mode allowing the transformer windings to do that vodoo that they do so well.... quashing common mode noise The split phase(balanced) output facilitates the cancellation of chassis reactive leakage currents.

Bob - I saw your comment that your betrothed actually participated in your subjective evaluations. She is definately a keeper. My wife refused any more involvement 20yrs ago.

Andrew - The input transformer doesn't require a dual primary as you've pointed out. But the benefit is only having to source one type of transformer and that if you feed it 220-240vac, you'll get the same at the output, balanced, without any changes to the schematic or wiring.

Audioferret - Very, very nice. I wish my Felicias looked as nice. Howzabout some some subjective comments on the changes wrought? (if such things are allowed here on DiyAudio)

Regards,
Paul (aka Occam)

[audioferret]

Paul,

Thanks for the detailed explanation. I will cite you on the website to help more advanced folks know what is going on. The specifics of how the conditioner works is still beyond my ability to explain.

The conditioner sounds excellent. My wife is a trained voice actress with 20 years experience in musical theatre, recording, and performing. She finally sat down just to listen to music...something I have not been able to do until now.
I played a few of her favorite recordings and she was really struck by the quality of the sound. She said that when she sang along, the resonances with her voice and the music really made her feel like she was singing WITH the artist.

For me, the conditioner has really brought my system to a point where I finally feel like the artists are in my house. The sense of THERENESS has really stood up. That is the best way that I can explain it without going into the thunderous lows, creamy mids, and velvety soft highs. Music has definitely improved.

This also made a nice impact on picture quality by feeding my DVD player and VCR. Noise was reduced, resulting in a clearer, less grainy image. Blacks were definitely blacker, particularly the bars at the top and bottom of widescreen presentations.

In my short, objective opinion, this thing ROCKS!

[ozone_stink]

Would any of you generous types list some Digikey part numbers that would work as transformers for this project?

Thanks for your help!!

[audioferret]

I will post a page with a complete parts list, part numbers, and links...it is on my to-do list. I need to conduct more tests on its power capacity for Paul (Occam)...that will be done tomorrow.

more to follow...

- AF