[Occam]

MAJOR REVISION as of 2/7/06

This thread is for discussion of the Felicia balancing powerconditioner, which is an enhancement of Jon Risch's SQ&D iso trans project -
http://db.audioasylum.com/scripts/t.pl?f=tweaks&m=43988

I've left the schematics on a 'sticky' thread to allow reference to it while convesing in a separate window on this thread -
http://www.audiocircle.com/index.php?topic=18441&sid=8fde56b5616010155d6f2364fe935806
When participating in the constructor's thread, please open a separate window to that thread as this will be edited and updated to reflect current status

Please note that this project involves mains voltages and can kill you. Unless you follow accepted safety precautions (and implictly understand them) do not! undertake this project. You must have a meter capable of reading at least 300VAC to implement this project.

My personal implementation is in reality an ugly 'boa constrictor' powercord, Input is a cord with a wall plug, and output is a cord(s) terminated with an IEC plug(s) that goes directly to you component(s).

The fuses shown are NOT optional! I use 1amp fast blow fuses. The maximum rated fuse you may use is the same as in the component you are powering!

The following components are reccomended (this will change as surplus stocks are exhausted and/or better components are found)

Input/Output - Volex 17605 powercord, cut in half, providing input and ouput cables and plugs
http://www.carlton-bates.com/cb/invsrch/flocresult.asp?svend=BC&Start=0&Offset=10&srchfield=stkmfgpart&pmvndstkn=BC%2D17605%2FB1%2D50%2F10&pumdbn=41056

Note - the Signal transformers from BG Micro are no longer in stock. Many manufacturers make these 'World Power' chassis mount transformers, Signal, Triad, Stancor, Hammond, MCI.... but $40 retail is not as attractive as $10 surplus. Anyone finding good, inexpensive alternatives, please PM me.

Transformers - Signal Transformer 175va dual bobbin transformer
http://www.bgmicro.com/prodinfo.asp?sid=078189814814814869201136182&prodid=PWR1164&page=1&cri=signal+transformer&stype=3&time_out=44:58

Please note that when primaries are wired in series , 240v, and used to either input or output 120v their rating must be cut in half., ie, the 175va transformer is downrated to 87va. This project and the components suggested is for source components. Here are wiring diagrams specifically for those Signal A41s. They come with the primaries wired in parallel (which you don't want for the reccomended 2 transformer version,and you must rewire for series connection), and the secondaries also wired in series which you do want -





EDIT as of 10/7/05The current reccomendation ([used with the specific Signal Transformer A41], is now -

C1 = 18uF 400VDC Jantzen CrossCap (Parts Express: 027-938)
C2, C5 = 0.47uF 400VDC Jantzen CrossCap (Parts Express: 027-906)
C3, C6 = 0.1uF 400VDC Jantzen CrossCap (Parts Express: 027-900)
At least for non-silly money. All caps should be aligned the same, in other words the direction of the writing should be consistent.

As the secondaries are running at 15 odd vAC, any voltage rating, 250vDC being the lowest common rating, should work fine for C1, C2 & C3, but please feel free to experiment, the seconday is at 15 volts so you don't need a X2 cap, and if you're feeling wealthy use Auricaps by all means. Feel free to bypass with the most esoteric of adequately rated bespoke caps. Actually, it is (IMO, as well as Tianguis, Phil, and others) a very worthwhile upgrade to bypass each of the capacitor groupings with a .01uf 600v Auricap.
 
As with any 'tweak', its efficacy depends on many factors -
Your systems characteristics, resolution, etc......
Your predeliction for mass hysteria.
Your specific metrics (i.e. What pulls YOUR monkey bone)
YMMV

a whole passle of .25 female quick connects and a tool for crimping them. The transformers have qc terminations and it makes construction quite easy. If you've a mind to reap whatever benefits of hardwiring with solder, be my guest.

wire - quite useful. Pick whatever with adequate voltage rating. I'm not going there.

[JoshK]

Let me just say that Paul and I have had a great time over the course of 3 seperate Saturday's building different variations of the Jon Risch recipe.  This isn't the same JR design that is sold by DIYcable and written up on his page but rather a balanced/filtered/isolated design he mentioned on AA some while ago.  

I am quite stunned with the results we were able to acheive!  The differences were profound in my system.  We first started out with my system prior to putting in a dedicated line, as was the case heard at the Rave meeting at my abode.  Then on the second saturday, I had installed the dedicated line.  The differences weren't as large as before, because the d-line did help a lot but they were definitely still there.  Then we did a few variations and gained even more.  We will go through the various ideas we tried in due time but needless to say I am quite satified what we were able to acheive with so little money and a great design!  

I heard rumor that the Felicia bested a big name hi-end PC at the Gotham meeting, which I was suppose to attend but spur-of-the-moment legal matters kept me away. It definitely did best the OneACs that I modded for myself and Daniel.  At first listen we weren't sure but later configs made it quite clear.

more to come....

[Occam]

Josh - Firstly, and apology for not adequately acknowledging you contribution to this project. It simply would not have happened if it were not for you and your many, many hours of effort.

Given the many hours you've put into this and the shared subjective evaluations, I can state that we've calibratied our subjective vocabulary against each others. In the future when Josh posts his impressions of a component, I'm relatively sure I'll have a good idea what it sounds like.

The Gotham Audio Society meeting today was quite an eye opener, as I'd previously not been able to compare our efforts against commercial products.  The majority of members who opined told me that they preferred Felicia to the AlphaCore balanced conditioners. Then again, those who preferred the AlphaCore probably didn't confide to me.....

Suffice it to say that the Felecia held its own and is competitive with commercial products, within its power constraints (in its present guise it can't power amps)

One thing I have learned is the power of the dpdt switch. Nothing better than a proper switch to insert/add components while listening. Gordy just sent me some 4pdt switches!

Hopefully, this thread will serve as a repository and exchange of info so that Felicia will evolve and become even better!

[AKSA]

An inspired contribution to the 'dirty mains' problem!!

Congratulations, Paul and Josh.......
 
Cheers,

Hugh

[ohenry]

Cool DIY project, congratulations to Occam and JoshK.  

Occam, when you stated that GFCI outlets need to be installed, could I use a GFCI breaker mounted in the box ahead of the outlets and have the same protection?

Thanks for the hard work.

[ctviggen]

Henry,

That's the way I would do it (a GFCI breaker).  Can you build any of those three versions?  What about the ground?  Do you still connect it to the component, or is that why you're using GFCI outlets?

[JoshK]

Paul is giving me way too much credit here, although I understand the idea of what we were doing and did help some in construction of the various implementations it was Paul's knowledge that allowed us to acheive such great results!  It was also his scientific tendencies that pushed us to take it up a few notches to its current variation.

I will state a couple of obvious things.  This will not do anything for your amps.  IMO they should be dealt with in a much different fashion anyhow, so I really don't care, but this should work for nearly all sources and most preamps (each individually).  The really cool thing about this is unlike most solutions on the market, it isolates the components from one another as well as the line while providing balanced filtered power.  

At the cost it takes to build one of these, it is easy to afford building one for each component!  So the current limitations aren't as restrictive as you might first think.

[ctviggen]

I see -- so you're ignoring the ground, which is why you use GFCI outlets.  What do you physically do with the ground?  I currently have a cable (12/2 + ground) run from my breaker box to power my amps.  The ground in the cable is connected to the ground on the outlets.  I could run 12/2 without ground, but I'm not sure they even make this cable, or do they? If you have a ground running to where you want to install the transformers, what do you do with the ground?  You can't connect it to the box, as that wouldn't meet code.

[JoshK]

Bob,

I hestitate to answer because my I am no expert in grounding, it is what pains me in DIY most.  However, what we did was connect the ground from the input side of the 'Felicia' to the output side of the 'Felicia' so it just passes through.  (Paul correct me if I am wrong here).  For the balanced config (we tried so many I almost forget what was final) I think the center tap is also tied to this point.

[klh]

Roughly how much would it cost to build one of these? For those who aren't comfortable building one of these, would you consider building some and discretly selling them?

[Occam]

Ohenry - The reason for suggesting a GFI has to do with the nature of most of our components. Typically, the neutral line is neither fused no switched within a component. (on all my own DIY projects I'm now using an IEC inlet with dual pole switch and fuses, $1.49 from apexjr.com.) Unbalanced mains do not have power flowing on the neutral, and assuming proper wiring of the mains outlet, this is not problematic. But after balancing we now have 60VAC on that neutral line and 60VAC (antiphase) on the hot line. In the event of a component failure, we might find 60VAC shorted to the chassis, with no fuse on that neutral line to provide safety.  Its pretty hard to kill oneself with 60VAC, 120VAC is often fatal, and 240VAC is VERY often fatal. This is why a GFCI is reccomended.
I defer to ctviggen on the breaker located GFCIs as I'm not experienced with them, but if they do trip with anything above of a set level of ground leakage, they address those safety issuse. I'm checking into having one installed in my own breaker box.

JoshK and I originally built the first 2 transformer version, with a single output as we did our development balancing only his CD/SACD player feeding directly to his Perreaux integrated. Based upon our own evaluations, we were astounded by the improvements it offered. We scheduled a 'shootout' at the Gotham Audio Society against a Alphacore balancing conditioner as we'd previously not had a chance for comparison with commercial products. The day before, in setup, I found that the Creek passive pre was not an ideal mate to my AKSA 100 N+, and threw my warhorse Nakamichi CA5 II into the mix. I built the first and only dual output isolated version that night, and that is what I demoed the next day, untested, as my amp was at the Gotham meeting site. Not too bright......
Nevertheless, the unoptimized dual output version was certainly at least the equal of the AlphaCore. In retrospect, it might have been brighter to demostrate with the more proven single output Felecia, feeding both source components.

Given the above, I would suggest building version #1 first as this is a verified and partially optimized version. Extending to the latter 2 versions only requires the addition of 1 additional transformer and some thingamabobs. This constructor feedback driven project will hopefully be a learning experience for all involved. Rather than have some clowns (Josh and I) say "here is the definitive....." I'd much rather see this as a syndicalist project, folks interacting for their own mutaul benefit.

Felecia will hopefully be a community project and I'm expecting that feedback from constructors will allow us to further optimize the design

[Occam]

I see -- so you're ignoring the ground, which is why you use GFCI outlets.  What do you physically do with the ground?  I currently have a cable (12/2 + ground) run from my breaker box to power my amps.  The ground in the cable is connected to the ground on the outlets.  I could run 12/2 without ground, but I'm not sure they even make this cable, or do they? If you have a ground running to where you want to install the transformers, what do you do with the ground?  You can't connect it to the box, as that wouldn't meet code.

Bob - The ground is not ignored or broken! The grounds as shown on the schematics are tied together. If you're housing it in a metal chassis, the grounds should be connected to the chassis ground as a 'star-ground'. The mains ground is tied directly to the centertapped ouput transformer windings. I do not like or condone the idea of floating balanced for both safety and performance issues. Even with 2 pronged components, a ground is ultimately established via the interconnects to other grounded components, unless you're off the grid on batteries.

Josh - Aw shucks. Regardless of your self effacing manner, this project would be nowhere without you. This is a community project, and I fully expect feedback from constuctors to make it even better.

klh - If you click on the links for the components on the first post, all will be revealed.  For a single output device it runs $18 for the 2 transformers, $4 for the oil motor run cap, $7 for the Volex, $.75 for the X2 cap and $.50 for the loading resistor. But the shipping and cost of whatever box you put it in is what gets ya.

[ohenry]

Ohenry - The reason for suggesting a GFI has to do with the nature of most of our components. Typically, the neutral line is neither fused no switched within a component. (on all my own DIY projects I'm now using an IEC inlet with dual pole switch and fuses, $1.49 from apexjr.com.) Unbalanced mains do not have power flowing on the neutral, and assuming proper wiring of the mains outlet, this is not problematic. But after balancing we now have 60VAC on that neutral line and 60VAC (antiphase) on the hot line. ...

So, when using the first version fitted with an IEC plug to the component side, it would be necessary to have the neutral line fused in the component or to have the GFCI upstream?  

Also, are there going to be "issues" when the neutrals aren't switched in the components? (it would seem that the CDP, preamp, etc. would remain active and the unit would have to be controlled via a switch on the transformer power input).

I hate to appear totally thick, but I often overlook the obvious.

[ToddSTS]

Cool.  Do you have any pictures of the completed device?

Thanks.

Todd

[Ulas]

---deleted---

[Occam]

I hate to appear totally thick, but I often overlook the obvious.

Not at all.... The concerns raised by you are spot on, especially as they deal with safety issues. I can only express my gratitude to you and ctviggen for raising these serious concerns that I'd not given adequate thought to.

I'll revise the schematics on the 'sticky' page to reflect the following-

1. The input 'hot' line should be fused to reflect the maximun draw allowed for the input transformer. In the case of the 175va Signal transformer initially reccomended, for the single output,  it should be a 1amp fuse, reflecting the downrating required by the series connection of the primaries down to 88VA.  In versions 2 & 3 where the input primaries are configured in parallel, a 2amp fuse should be used reflecting that 175VA rating. As the transformer is an EI core feeding a 'small' capacitance of 15uf, that rating should not cause turn-on surge tripping.
Also, if the unit is plugged into a large draw component, like an amplifier, you want the fuse to trip rather than have the transformer go into meltdown.

2. All output lines should be fused on both legs, as they are both now 'hot'. If the intended component is has both lines fused and switched internally, you may forgoe this, but frankly, you never know what you'll plug into what, so I'd include it regardless. Sort of a belt and suspenders approach.  The fuses used should be exactly those in the component you intend to power.

3. When working on components with the cover off, NEVER have it plugged into a balancing transformer. Do your mods or troubleshooting with the component pluged into a conventional single phase line for safety reasons, if the unit has to be powered.

And yes, if you've a GFCI [EDIT ------deleted---].......nor am I conversant enough with GFCI issues to opine.

[Occam]

An additional caveat - Never use any balancing transformer with older component that may have neutral tied to the chassis. Although this has been a UL no-no for over 20years, some golden oldies such as some Mac tube amps (I think?) do internally connect neutral to the chassis assuming that the neutral line is grounded. You can check this with a ohmmeter by making sure you've an open circuit between both (either) blades on the powercord plug and the chassis with the unit turned on but not plugged in.
This caveat applies to both Felicia and commercial units.

[Ulas]

---deleted---

[Russtafarian]

Very cool project Josh & Paul!  If I didn't already have an Equitech, I'd dive right into this one.  I may still add some filtering as my 2Q is a five year old industrial model.

[ohenry]

---deleted---

Just kidding.    

Occam, thanks for the explanation and continuing to encourage through a helpful attitude.  Now, it's time to do some shopping...