[GBB]

Well it's winter time even here in California, meaning it's time to be inside soldering away while mother nature does her thing.
This past weekend I finally got around to building Occam's latest inspiration, the Felix line conditioner.  Take a look at this thread for more details on the Felix:
http://www.audiocircle.com/index.php?topic=25757.0

Knowing that it was inspired by the Audience Adept, I was expecting good things and I was not disappointed.  Here are the parts that I used:

--- Coilcraft P3717-A CMC, available on Coilcraft's website
--- I used X1 rated polypro caps from Digikey in values of 1uf, 0.1uf, and 0.01uf on each side of the CMC
--- Part numbers are BC1576-ND, BC1587-ND, and BC1588-ND - Vishay/BC 440VAC X1 rated caps

Remember to use fuses as well.  And remember that you are dealing with AC line voltages which can be lethal.  Only attempt a project like this if you know what you're doing.

I built the Felix into a small box that I bought at the local Fry's and then soldered line cord to both ends.  It's a metal box so I lined the inside with dynamat to make sure there was no chance of shorting things out.  I terminated one end with an AC plug and the other end with a female AC receptacle, both of which I got at the local Lowe's.  I'm sure you could play with fancier connectors and more expensive capacitors but this combination already does quite well and sounds really great.  Here are a few pictures of my Felix along with some parts for a 2nd yet to be built Felix.





As soon as I finished it, I put it into use with my modified Squeezebox 3 and I found a somewhat interesting result.  I've long been a proponent of linear supplies for the SB3, finding them a significant improvement over the stock switching supplies.  Well with the Felix I got a different result.  The combination of the Felix and the stock switching supply sounds outstanding and in fact it sounds better than either the linear supply on its own or the linear supply and the Felix combination.  I'm not sure I can explain why this is true but it's an obvious difference. 
I did find that there was a difference which way the switching supply was plugged into the Felix.  The switcher isn't polarized so you can plug it in either way.  One way sounds obviously better.  One theory that has floated around for a while is that part of the reason people liked linear supplies better is that the switcher could be injected noise back onto the AC and degrading the sound of other components.  The Felix will stop that from happening and maybe that's all that's needed.

So there you have it - a recipe for outstanding digital sound with a very modest investment.  The Felix probably cost me $30.  The Squeezebox lists for $299 although I got mine cheaper than that at one of Slim Devices semiannual sales.  And I spent perhaps $50 modifying it as documented in another thread on this Circle.  This combination absolutely competes with much more expensive set ups.  No expensive transport, no expensive digital cables, no expensive DACs.  Just really good sound.

Happy listening.
---Gary

p.s.  A big thanks to Occam for the design and to Gordy for the push to get started on this project.

[randytsuch]

Hi Gary
Interesting findings.
I remember reading a thread somewhere, maybe at the slim devices forum where someone was talking about the noise the SB switcher put back into his system, but I don't remember the details.

Still, I am surprised that the felix and switcher are better than the felix and your linear. 

Randy

[Folsom]

I am not sure quality difference but X2 rated Panasonic capacitors are a lot easier to deal with, they have leads on them and the shape is not as big either I believe.

I to find it hard to believe that your linear does not sound as nice. Perhaps your linear suffers from too much voltage drop under load somehow?

[tanchiro58]

Gary,

Did you align and solder these components on a pcb board in parallel like Occam suggestion? If it is possible would you post a detail pictures that you built the Felix in the aluminum box? Thanks in advance.

Regards,
Tan

[GBB]

Interesting findings . . .   I am surprised that the felix and switcher are better than the felix and your linear. 

Randy - me too.  It's such an unexpected result that I thought it important to share it.  It's actually good news since switching supplies are "greener" which is always a good thing.  Someone asked if I was using the stock walwart and the answer is yes - this is the small switcher you get when you buy the Squeezebox.

I to find it hard to believe that your linear does not sound as nice . . .

DoS - feel free to not believe me, but I'm not making this up.
In fact, I'd actually be more comfortable if you ignored this thread.  Your history of DIY makes me nervous that you might hurt yourself if you tried a project like this.  Do us all a favor and don't try this at home.

Did you align and solder these components on a pcb board in parallel like Occam suggestion? If it is possible would you post a detail pictures that you built the Felix in the aluminum box?

Tan - I didn't bother using a PCB board for this.  I hooked the CMC to the 1uf caps with some 18 gauge bus wire and then hooked up all the other components directly to this bus wire.  I hot glued the components to the box and then wired the inlet and outlet cables.  I again used hot glue as strain relief where the wires enter the box so there is no chance of pulling the cord and moving wires around.

If you want to discuss construction in more detail, it might be better to move this to the main Felix thread:
http://www.audiocircle.com/index.php?topic=25757.0

---Gary

[JoshK]

I actually find your outcome quite interesting and neat.  Switchers are nice in the fact that they are green but they also regulate the voltage quite often (or nearly always? I'm not sure as I am not a power engineer). 

I've often wondered if the reason why linears outperform switchers is wholly the noise part and if dealt with appropriately would solve the issue.  I do know that the Felix did wonders for my DEQX, which has a swithcher internally.

[Occam]

Gary,

If you try your Felix with the SB used as a transport feeding an external dac, I'd certainly be interested in your evaluation.

I realize you feel the definitive use of the SB is to do the straitforward mods you so generously shared, obviating the need for an external dac -
http://www.audiocircle.com/index.php?topic=49342.0
but for those of us who already have a dac we like, and are too old and decrepit to do smd rework  , it provides yet another option.

TIA,
Paul

[Gordy]

Thank you so much for posting your findings Gary!  It's great to hear that others are building the Felix's and liking them     It would be very cool to hear your thoughts as you add them to your other supplies as well.

I now have six in my system, a 10a in each of my SKA300 amps supplies, two 3a externals feeding my Olive Symphony, a 3a in my Twisted Pear Bipolar supply feeding my P3a dac and another in my Aikido pre's supply.  I've an all poly cap Felix built but, not installed yet, for the output of the Aikido's 12v DC filament supply as per a Lynn Olsen suggestion.   

Tan et al, 

Paul mentioned in another thread that it would be ideal to keep the leads of the .01Uf cap as short as possible, that is, directly across the cmc leads. 

[tanchiro58]

Tan et al,

Paul mentioned in another threads that it would be ideal to keep the leads of the .01Uf cap as short as possible, that is, directly across the cmc leads.

Thanks to all of your kindness (Gary, JoshK, Occam and Gordy).

Your helps are worth in this thread. I have also learned a lot in this and other thread especially the Lab. I will have questions about if I can build the Felix in any audio component's PS (battery or AC?). I have been using quite a few power conditioners and I did not really like the sound of my system. It is kind of constricted sound. So adding the Felix to the power conditioner would that be help? Thanks.

Tan

[Russtafarian]

Thanks Gary, you've pushed me over the edge into finally building a felix.

Will that CMC pass enough current to feed a power amp or should it be used only for components with low current draw?

Russ

[richidoo]

Neato. I went back and started reading the thread you linked. Very cool. Definitely worth trying it out. I too have been linear PS proponent for SB, now I gotta hear what you have found!! Thanks Gary. Looks like a nice clean job too.

Josh, I really like your new avatar. It's one of those you wish you could click and magnify... A little different from the last one? haha
Rich

[Gordy]

Thanks Gary, you've pushed me over the edge into finally building a felix.

Will that CMC pass enough current to feed a power amp or should it be used only for components with low current draw?

Russ

Russ,

The 3717a that Gary used is rated at 3a only.  For power amps you'll want to use either the 10a rated 4018a or the 17a Miller which is linked to the Mouser source in the other thread.  The Miller cmc is the one used in all the demo's at the NY Rave demo's over the last year or so.

[Speedskater]

I think that we should remind other builders that:
a) The Squeezebox does not draw very much current.
b) Gary has carefully placed as many components in a small box as possible.
c) The Dynamat inside the box will inhibit cooling.
So if your systems draws more power get a bigger box!
And don't forget to safety ground it.

[kyrill]

valuable thread  thx

what i do not see are the values of the cmc's  with the caps you mention their value's in uF but the cmc have also many values between mH - uH  or is the value you merely look at the amperage? So you then take the highest value in mH which you can choose from with a certain amperage?

[GBB]

valuable thread  thx

what i do not see are the values of the cmc's  with the caps you mention their value's in uF but the cmc have also many values between mH - uH  or is the value you merely look at the amperage? So you then take the highest value in mH which you can choose from with a certain amperage?

I listed the CMC part number.  A quick google search would have turned up the following data from Coilcraft's website.  Use the CMC with the appropriate ratings for your application.  As others have noted, the current draw of the Squeezebox is minimal, so the 3717 seemed like the right choice here.
---Gary


               Common        Diff.          DCR          Volt.          Amp.
               Mode L         Mode L
P3717-A    25.0            1000          0.30         1500             3
Q4007-A    4.5              150           0.06         1500             5
Q4018-A    1.5               35            0.02         1500            10

[JoshK]

FWIW, I built a Felix into my Squeezbox PSU (linear) and I used the 3717.  I did this some time ago.  What I haven't done was install a switch to bypass the Felix to compare with and without as I built the PSU with the Felix in, so the results are the results of both. 

[kyrill]

the DCR rating of the P3717-A 0.3 R seems relatively high for a psu where the the lesser is the better.
 
If you would parallel 2x P3717-A would that lower the mH?

how did you order? I understand you have to order a  tray of 6 units as a minimum?

[JoshK]

Note:  Please do not abuse the free samples from Coilcraft or they, like many other parts manufacturers, will quit fulfilling the small orders from the hobbyists.  Then you do a disservice to all of us diy'ers out there.  They are cheap and they do allow small quantities, so don't be cheap yourself and pay for them.

Sorry if that is totally obvious, but it needs to be said as abuse of free samples has spoiled a lot of good services diy'ers enjoyed in our forums.   If you want to order less than the minimum quantity, order the minimum and then post on one of these threads that you have extras and someone is likely to take them off your hands.  Its not that big of a risk @ $6/ea. 

[tanchiro58]

Note:  Please do not abuse the free samples from Coilcraft or they, like many other parts manufacturers, will quit fulfilling the small orders from the hobbyists.  Then you do a disservice to all of us diy'ers out there.  They are cheap and they do allow small quantities, so don't be cheap yourself and pay for them.

Sorry if that is totally obvious, but it needs to be said as abuse of free samples has spoiled a lot of good services diy'ers enjoyed in our forums.   If you want to order less than the minimum quantity, order the minimum and then post on one of these threads that you have extras and someone is likely to take them off your hands.  Its not that big of a risk @ $6/ea. 

JoshK

I would totally agree with you and do not mean to attrack to people who want "free sample." Hence I ordered one. That is coilcraft offering though. Please do not misunderstand me. Thanks.

Tan

[JoshK]

Note:  Please do not abuse the free samples from Coilcraft or they, like many other parts manufacturers, will quit fulfilling the small orders from the hobbyists.  Then you do a disservice to all of us diy'ers out there.  They are cheap and they do allow small quantities, so don't be cheap yourself and pay for them.

Sorry if that is totally obvious, but it needs to be said as abuse of free samples has spoiled a lot of good services diy'ers enjoyed in our forums.   If you want to order less than the minimum quantity, order the minimum and then post on one of these threads that you have extras and someone is likely to take them off your hands.  Its not that big of a risk @ $6/ea. 

JoshK

I would totally agree with you and do not mean to attrack to people who want "free sample." Hence I ordered one. That is coilcraft offering though. Please do not misunderstand me. Thanks.

Tan

I didn't think you did anything wrong, but since you mentioned the free samples, I felt it was obligatory to plead for us and any lurkers to not abuse this angle.