FELIX questions for my setup

kyrill · « **Reply #20 on:** 21 Mar 2009, 09:51 am »

hi Anthony

I thought about the 20 and 21 too but their inductance become 1/3 to1/7 of the 18. which is a lot.
o.o32 ohms is already really really low. It is like a powercable of 2-3 mtrs long incl contact resistance
The less inductance the less filtering
The pcb is fine for amps. I would take point to point when you come close to 7 A. That is not yr amp

Josh cannot advise you to go against regulations as he has a public responsibility

but the auricap is used in high voltage ( much higher than line) in power tube amps and in line conditioners ( the real expensive high end ones)

mgalusha · « **Reply #21 on:** 21 Mar 2009, 01:36 pm »

Warning, preachy safety post...

Even if the caps are rated for the voltage they can and do fail. I recently had a non X rated polypropylene film cap fail in a power supply and it took a very expensive R core transformer with it. When the cap failed it shorted across the transformer secondary. Of course the fuse blew but not in time to save the transformer.

All my Felix filters have X rated caps. They may sound a little better with a boutique cap but I've experienced first hand what the failure can do. The thought of a cap failing in a dead short across the line is very uncomfortable for me. IMO it's just not worth the risk.

</warningOff>

JoshK · « **Reply #22 on:** 21 Mar 2009, 03:30 pm »

Quote from: kyrill on 21 Mar 2009, 09:51 am

Josh cannot advise you to go against regulations as he has a public responsibility

but the auricap is used in high voltage ( much higher than line) in power tube amps and in line conditioners ( the real expensive high end ones)

As Mike explained, it isn't the voltage that is the problem, it is the failure mode. When non-x-rated caps fail, they are not gauranteed to fail open like an X-rated cap. If they fail short damage can occur. Worse, what if they fail semi-short? Then they create a leakage current, maybe not enough to trip the breaker but enough to cause a fire.

I should have not even mentioned my experiments.

The difference between a Felix with boutique caps versus Felix with x-rated caps was small. The difference between a Felix and no Felix is not small.

kyrill · « **Reply #23 on:** 21 Mar 2009, 03:52 pm »

i agree Josh
but there is a but?

Is there one story already found on the internet describing a failed high end audio cap in this position causing fire?

sonicraft dare to sell metal film boutique caps as they say they will open this is there response to what i mailed them
"Caps rated as X1(440vac?), X2(240vac) are specified (and listed) are 'guaranteed'/certified to fail either totally open, taking it out of the circuit, or totally shorted, which would trip a breaker. Because they can fail shorted, they are used across the line, from hot to neutral. These are used to address differential/normal mode noise.

Caps rated as Y1,Y2 are specified .... to fail totally open. This means they may used also from Hot/Neutral to safety ground as they will not nominally put mains voltage to a grounded chassis, even if they fail because they will (hopefully) only fail open. These are used to address common mode noise.

Indeed, the characteristics (frequency vs impedance, etc...) of the cap(s) can be subjectively perceived (I will inevitably rue this statement). Personally, I only use 'rated' caps for mains use, and think the proper combinations can meet my needs.

Mains X & Y will come in ceramic (inexpensive and mediocre performance) and metalized film (Mylar or Polypropylene) or metalized paper. I've not found foil caps certified for these uses, I assume because they lack the self healing characteristics of metalized caps. Occam"

Kyrill,

It is common knowledge that film and foil tend to fail shorted unless
considerable current is involved. Metalized tend to arc clear. I tend
to think of them as self-diminishing rather than self-healing. None of
the caps we carry are certified for use in high voltage AC applications.
However, that does not mean they can not be successfully used. Again,
what is the voltage present in your application?

I would only recommend metalized caps for this application. On a
budget, you could use the 600VDC Sonicap G1. The Cardas cap would be a
top contender being metalized with a duplex-ed polypropylene/teflon
composite.

Remember that DC voltage ratings need to be multiplied by 0.7 for AC
voltage. Then I would add a safety factor of at least 1.5 due to
spikes. A spike will typically be trapped by the cap. Due the little
or no isolation or regulation, your AC can present very high amplitude
spikes. Yourself and your neighbor will have all kinds of different
power-factor/reactive loads connected in parallel to the circuit.
Translation: All kinds of noisy spike making appliances.

BTW, shunting noise to ground should only be done as a last resort.
Further, the results will depend on ones ground integrity and layout.
For many, it could create as many problems as it solves.

and last from http://didnt.doit.wisc.edu/audio/CDP/cdp.html
n April 2004, I learned about a tweak that allegedly could make some cheap DVD and CD players sound much better: putting two 0.47UF 600V Auricaps across the hot/neutral wires in the power input of the player is supposed to filter all sorts of crud out of the power. Auricaps are pretty expensive, so I tried it first with similar A/C power rated caps, but that didn't do anything noticeable. Since I was building a DAC that needed 0.47uF caps in the output stage, I decided to order some and if the tweak with the AC didn't work out, I would have use for the caps. Well, so I put them in (behind the fuse, so they don't fail and catch fire while the unit is unattended*), powered up and sat back to listen. It took a while before I was able to lift my jaw off the floor... AMAZING detail, sound stage definition up a full level of magnitude. Everything in the transport and built-in DAC must be working much better with clean power, as the amount of detail now coming from that player is simply amazing. One of the most effective tweaks, and very simple to install if you know what you're doing.
* i dont think this is a just faith (Kyrill)

THIS STILL MEANS THAT JOSH and MGALUSHA ARE RIGHT

anthony a. · « **Reply #24 on:** 21 Mar 2009, 06:14 pm »

Quote from: kyrill on 21 Mar 2009, 09:51 am

hi Anthony

I thought about the 20 and 21 too but their inductance become 1/3 to1/7 of the 18. which is a lot.
The less inductance the less filtering

okay, so the inductance of the 8118 is 7.3mh and dc resistance is 0.032ohm, whereas the 8120 has an inductance of 2.4mh and resistance of 0.008ohm. if i am understanding you correctly, then the 8118 has 3 times the inductance and dc resistance of the 8120, which translates into more filtering with the 8118. if that is correct, then perhaps the only reason some find the 8120 better on amps is due to less filtering and hence less dynamic constraint. would you say my understanding is correct?

ps. once i have decided on which choke to use, i can start deciding on caps.

kyrill · « **Reply #25 on:** 21 Mar 2009, 07:13 pm »

if that is correct, then perhaps the only reason some find the 8120 better on amps is due to less filtering and hence less dynamic constraint.

yes you understanding is correct BUT less dynamic constraint between 0.032 and 0.00x for my ears is non existent. I mean between 0.032 and no Felix BUT only in the dynamic constraint.
but with the Feix so much sweeter transparency

And then
1) buy the o.o32 coil
if you hear a difference between no Felix and Felix in the dynamic constraint
2) buy the other Miller

anthony a. · « **Reply #26 on:** 21 Mar 2009, 11:58 pm »

okay yeah i guess im just gonna buy a pair of each and try them out. in the end, i'll end up being out like $25 so no biggie. okay, so now that the chokes are in place, its time to talk caps. what is the best x2 or x1 cap i can use?

kyrill · « **Reply #27 on:** 22 Mar 2009, 10:27 am »

Those are the ones suggested in the original felix threads, see group buy http://www.audiocircle.com/index.php?topic=51941.0

anthony a. · « **Reply #28 on:** 22 Mar 2009, 05:46 pm »

thanks kyrill. yeah i seen those ones. they are as follows:
- Vishay/BC MKP 338 X1 set of two 1.0 uF, two 0.1 uF and two 0.01 uF

just getting ready to place the order on digi-key right now. in terms of fuses, did everyone put a fuse on each felix or are they not needed? if they are needed, which ones are recommended?

drmike · « **Reply #29 on:** 22 Mar 2009, 06:58 pm »

hello,where can i get a good case for a single felix?
thanks,
drmike

mjosef · « **Reply #30 on:** 22 Mar 2009, 07:25 pm »

RadioShak has the 'almost perfect' size black plastic box for a Felix built on the AC Group buy PCB.

http://www.radioshack.com/product/index.jsp?productId=2062282

kyrill · « **Reply #31 on:** 22 Mar 2009, 07:53 pm »

thx Mjosef
i have 3 of my Felixes like this ( all over the house)

or

unless the ones build in a former line conditioner
2 separate outlets for power amps Miller coils RC 8118
2x2 outlets for non power devices high inductance Coilcraft P3717-A

mjosef · « **Reply #32 on:** 23 Mar 2009, 02:40 am »

Here you go Kyrill, your Felix will look much better in the aforementioned RS box

anthony a. · « **Reply #33 on:** 23 Mar 2009, 05:07 am »

looking good. i have a really great idea for my amp box, i hope it ends up working out. the rs box seems perfect size for my needs.

daz_bike · « **Reply #34 on:** 23 Mar 2009, 08:30 pm »

Hi,

I hope someone can help me select the right size Mills CMC's for the following equipment. I use 230V/60Hz electricity.

Source: 250 Watts
Amps: 1300Watts (peak)
Plasma: 555 Watts

Thanks

anthony a. · « **Reply #35 on:** 26 Mar 2009, 07:10 pm »

just as an update, i received my order from digikey today and looking forward to putting these together. btw, i ordered the 1.0 vishay/bc caps as stated, but they are grey in color like the smaller caps. i noticed the ones from the group buy are blue in color. did they change the color recently? just want to be sure since i don't want to use the wrong part. from digikey, this is the link. can someone confirm these are the right ones. thanks.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=BC1576-ND

BradJudy · « **Reply #36 on:** 26 Mar 2009, 07:42 pm »

Those appear to be the correct ones (MKP 338 series X1 1.0uF). I don't know anything about the color change since I haven't ordered any sine the group buy.

drmike · « **Reply #37 on:** 27 Mar 2009, 02:52 pm »

do you use a fuse with the rs box?
thanks,
drmike

mjosef · « **Reply #38 on:** 27 Mar 2009, 09:00 pm »

I don't use any fuse on any of my Felix(a 20Amper on a 15A.fuse), those built for my own use.

With the RS box it is easy to drill a hole for a fuse-holder.

Edit: Actually, I ment I didn't install a fuse on my 20A Felix since my fuse box has a 15A fuse(no breaker panel in my apt).

I always fuse the 3A, 5A and 10A. Felix. Yeah, I'm FUSED.

anthony a. · « **Reply #39 on:** 30 Mar 2009, 02:50 pm »

Quote from: mjosef on 27 Mar 2009, 09:00 pm

I don't use any fuse on any of my Felix, those built for my own use. Only if I build it for someone else.

is the general consensus that a fuse in a circuit generally degrades sonics (however minute that may be)?