FELIX questions for my setup

anthony a. · « **on:** 16 Mar 2009, 03:02 am »

i recently went the pc route with usb dac running itunes. i am totally happy with my system's sound, but would like a further reduction in background noise. since the pc uses a switching power supply, it has an ever so slight hiss through the speakers only noticeable a few inches away. nonetheless, i would like to point out that i have tube monoblocks plugged straight into the wall on their own dedicated circuit plugged into hubbell 8300 hospital grade receptacles. my entire front end (including pc) is plugged into a bluc circle balanced power transformer. background noise is quite quiet, but recently i've been thinking if i should mod the pc switching power supply to incorprate felixes at with the ac input or dc output (or both). i am looking for input if this will make any difference to the background noise since everything is already plugged into a balanced power transformer on its own dedicated circuit. also thinking of something on the amp side. any input/suggestions would be greatly appreciated. thanks.

BobM · « **Reply #1 on:** 16 Mar 2009, 12:43 pm »

In my opinion, any kind of digital device will benefit from cascading power conditioning. Certainly a Felix is a good idea, because it conditions and also isolate the digital device from the rest of the AC circuit to a degree. You could also add chokes (aka Jon Risch's design) and a Felicia as well. They are both cheap enough and if they don't work in one place they could work in another.

Bob

BradJudy · « **Reply #2 on:** 16 Mar 2009, 01:03 pm »

I think a dedicated 5VDC power supply for the USB DAC could be the best approach, but it might require modification of your USB DAC (or choosing a different USB DAC). There are several DIY power supply options as well as pre-built options (look for SqueezeBox power supplies, which are also 5VDC).

mcgsxr · « **Reply #3 on:** 16 Mar 2009, 02:51 pm »

I use a linear PS for my SB3 (a Bolder PS, and a Bolder modded SB3), and I also use a Felicia.

Having tried it, there is no going back for this cowboy! My 96Db speakers will hiss with anything, and it is dead quiet as long as the tubes are not old.

Worth exploring for sure.

anthony a. · « **Reply #4 on:** 16 Mar 2009, 05:22 pm »

hey thanks for the replies. prior to looking into the felix, i had contacted several sources in making a linear power supply for my pc. due to its high amp rating, no one was able to build anything for me that wouldn't have been the size of my amp (believe it or not). so after i shot down that idea, i tried several different brand switching supplies for the pc and found one that was quiet in my setup. now that i did that, im looking to further reduce its noise by either chokes or the felix. if the felix works out, i would like to have it built into an enclisure with the switching ps to make it nice and neat. only problem is that im not a diyer when it comes to electronics so i'll have to find someone who would be willing to build it for me. any suggestions?

kyrill · « **Reply #5 on:** 19 Mar 2009, 11:02 pm »

yr tube mono blocs will also benefit from Felix if you keep the DC resistance of the coils under o,1 ohm
the difference with or -out felix is not subtle

anthony a. · « **Reply #6 on:** 20 Mar 2009, 05:13 pm »

hi kyrill, thanks for the reply. i am a total noob for electronic stuff. below are the specs for my monoblock amps. if you can tell me if the felix will work, as well as any further info i would appreciate. btw, i will have someone build it for me.

sensitivity: 1 volt
input impedance: 100 kohm
output impedance: 8 ohm
frequency response: 20hz to 20 khz
power output: 80 watts into 8 ohm
configuration: pentode
tubes: 2 x 12au7, 4 x el34 (per amp)

my speakers are 4 ohm.

kyrill · « **Reply #7 on:** 20 Mar 2009, 05:31 pm »

Hi Anthony

this is what i ordered for the Felix for the tube power amps
The capacitors are as described for Felix. These are the coils.
i had first .3 ohm coils but i could easily hear they robbed a bit my tube amp's ( Jadis Da-5, Orchestra)
liveliness. They sounded too polite
These I ordered at Newark and could not discern a disadvantage but much cleaner sound
Newark part number: 63K4086 BOURNS JW MILLER
8118-RC ~~$11.87~~ $12.08 Each
http://www.newark.com/jsp/search/productdetail.jsp?SKU=63K4086

resistance 0.032 ohms

anthony a. · « **Reply #8 on:** 20 Mar 2009, 05:51 pm »

okay great. im gonna order a pair then. i actually just bought (from another ac member) a few of the felix pcb boards to mount everything on. i assume these fit on the pcb no problem? also, i see these chokes provide just under 10a load and your amps output 40 watts. i know it should be sufficient, but since mine are double the power, do you think the chokes load is more than enough headroom for me? and, which caps did you find to be the best for this type of application?

kyrill · « **Reply #9 on:** 20 Mar 2009, 05:55 pm »

hi

yes they fit perfectly on the boards

the wattage of the 9 Ampere multiply it with 115V !!
SO if your amps stays under 1000 watts, no problem

I used the caps as described in the forum
but if i was a bit richer i would have choosen for the Auricaps same values
take >200V even if the wall current is 115. but just to be sure in excess conditions.

however Auricaps are not officially registered to be line level caps
Famous line conditioner brand(s) use them though
they do sound better, (much) more musical

yammy1688 · « **Reply #10 on:** 20 Mar 2009, 06:03 pm »

Has anyone ever tried Auricaps in the Felix? I think I'm going to give it a shot.

Quote from: kyrill on 20 Mar 2009, 05:55 pm

hi

yes they fit perfectly on the boards

the wattage of the 9 Ampere multiply it with 115V !!
SO if your amps stays under 1000 watts, no problem
I used the caps as described in the forum
but if i was a bit richer i would have choosen for the Auricaps same values
take >200V even if the wall current is 115. but just to be sure in excess conditions.

however Auricaps are not officially registered to be line level caps
Famous line conditioner brand(s) use them though
they do sound better, (much) more musical

JoshK · « **Reply #11 on:** 20 Mar 2009, 06:04 pm »

Quote from: yammy1688 on 20 Mar 2009, 06:03 pm

Has anyone ever tried Auricaps in the Felix? I think I'm going to give it a shot.

Yes I have. They are however not X rated, so do so at your own risk. I liked plain vanilla Jantzens better though and they are cheaper. Also not x rated.

anthony a. · « **Reply #12 on:** 20 Mar 2009, 06:13 pm »

excellent. we have liftoff!!

sorry for being so dense, but i see from the felix thread that most chose the vishay/bc mkp 338 combo over the vishay/roederstein. any reason why and how much do the auricaps go for?

and finally, can i use the same chokes from above to power my pc wallwart which has an input: 100v-240v --- 1.5A (50-60 Hz)
and output: 19v --- 3.42A? or would it be better to get one at a 5a rating?

kyrill · « **Reply #13 on:** 20 Mar 2009, 06:21 pm »

Felix is usually placed on the input side of the power supply
So yr PC need 1,5 A

DOnt take the same coils as for the power amps. Take the original Coilcraft high mH coils for the PC or the highest mH (value) Miller you can find. They all encompass the 1.5A the pc needs
The digital PWS from the PC is a real garbage generator

kyrill · « **Reply #14 on:** 20 Mar 2009, 06:24 pm »

Josh

can you link me to a post of yr OB speaker adventures?
Do you have made yr mind up how to construct your OB setup?

yammy1688 · « **Reply #15 on:** 20 Mar 2009, 06:27 pm »

Would you care to elaborate on how you felt the Jantzens bettered the Auricaps?

Quote from: JoshK on 20 Mar 2009, 06:04 pm

Quote from: yammy1688 on 20 Mar 2009, 06:03 pm
Has anyone ever tried Auricaps in the Felix? I think I'm going to give it a shot.

Yes I have. They are however not X rated, so do so at your own risk. I liked plain vanilla Jantzens better though and they are cheaper. Also not x rated.

JoshK · « **Reply #16 on:** 20 Mar 2009, 06:37 pm »

Quote from: yammy1688 on 20 Mar 2009, 06:27 pm

Would you care to elaborate on how you felt the Jantzens bettered the Auricaps?

Quote from: JoshK on 20 Mar 2009, 06:04 pm
Quote from: yammy1688 on 20 Mar 2009, 06:03 pm
Has anyone ever tried Auricaps in the Felix? I think I'm going to give it a shot.

Yes I have. They are however not X rated, so do so at your own risk. I liked plain vanilla Jantzens better though and they are cheaper. Also not x rated.

Been too long since I evaluated caps in this role. Occam and Larry did a whole lot more than I. I just was tee'ing off their results.

Note that this was mostly in the experimental phase. To leave non x-rated caps in this position long term presents a significant risk that you should not dismiss.

Let's say your house burns down. Let's say it wasn't cause by your diy project but somehow the insurance investigator learn of your diy project with non-rated caps. There is a chance you wouldn't get your claim honored.

JoshK · « **Reply #17 on:** 20 Mar 2009, 06:42 pm »

Quote from: kyrill on 20 Mar 2009, 06:24 pm

Josh

can you link me to a post of yr OB speaker adventures?
Do you have made yr mind up how to construct your OB setup?

Look at the "what are you currently working on" thread. I basically scrapped the OB idea for now. I am concerned that my room is just not congruent enough and instead am making an Abbey clone instead.

anthony a. · « **Reply #18 on:** 21 Mar 2009, 01:36 am »

before i place an order, i would like some more info on the miller chokes to be used for my amps. kyrill has suggested to use the miller 8118. i read in a thread that occam uses 8120 for his amps and these were also used at rmaf. miller has 8118, 8119, 8120 and 8121. since i will be using pcb boards (from group buy), they are speced at 10a max for their wire traces. obviously my amps won't exceed that, but i would like to use the 8120 or 8121 to be sure i won't be limiting dynamics in any way. would it be suggested to scrap the pcb boards for my amp felixes and go point to point or can i use they 8120 on the pcb's no problem and not worry about the 10a max traces.
in terms of the caps, i guess i could go for the standard vishay/bc mkp 338 x1 combo, but i really would like the best sounding ones i can get. if the felix is installed with a fuse (which i assume most do), will the auricaps be safe in a catastrophic event? i mean realistically, forget about liabilty/insurance, im just strictly speaking about safety. (reason i ask is because i was going to get a rsa duke for my amps which essentially uses all auricaps anyways).

JoshK · « **Reply #19 on:** 21 Mar 2009, 02:18 am »

I don't wish to comment on the Auricap.

As far as CMCs go, get the biggest rating (amps) for your amps and the smallest for your source (which means the biggest inductance).