X-CAN V3

[hower]

I have followed the V3 Tweaks in this site with great success.

But I have one small question here.

There are these 4 little film cap between the 4x 100uf Cap and the 4x 220uf NP cap? What are their values? How to read them? Sorry, I do not know how to read the value on such cap. Can anyone please advise me on their value?

[PinkFloyd]

They're usually 1uF (one microfarad) Do they have something like "1J" written on them?

[hower]

I opened it up again a moment ago, and these are the writing on them

1) 470nJ 63

2) 1u0J 63

What are these values?

What are they for?

Is it worth changing them to something better?

[Stormy]

Don't hold me to this...

1) 470nJ 63 = 470nF, 63 Volt rated

2) 1u0J 63 = 1.0uF, 63 Volt rated

It's the stupid industry habit of using the SI prefix or unit as the decimal point (e.g 7.5V becomes 7V5, 2.5 Megohms becomes 2M5R).

I'm not sure whether the "J" is important or not... anyone else know? I'm pretty sure caps aren't rated in Joules, lol!

Also not sure what they are for, but they might be worth changing if they are in the signal path (which it seems they might be) and are of the usual poor quality that MF use for their kit.

[thegreatroberto]

J is the tolerance,5%

[hower]

So, any suggestion what cap to change to? Any brand that is good to start with?

[PinkFloyd]

hower said:

So, any suggestion what cap to change to? Any brand that is good to start with?

Here's where it gets awkward "size wise" a 1uF polypropylene (for example) would be about 5 times the size of the existing 1uF polyesters (maybe even larger than X5) and would have a lead pitch of about 25mm.

You can appreciate it's "tight" enough inside the V2 as it is but, by all means, if you can squeeze some polyprops in then go for it.

I tried it some time ago and didn't make much of a difference to the sonics (nowhere near as noticeable as the PSU cap upgrade) but this may be an area of the amp that's worth experimenting with again. Please do remember that the main compromise here is "physical size" and take that into account "before" ordering polypropylenes that resemble a small house brick in dimension

[hower]

I am referring to the V3 here... But maybe you are right, size might still be a issue inside a V3...

[PinkFloyd]

Let me give you a visual example of two identical value caps, one polyester the other polypropylene.

The yellow one you can see is the stock cap for the V2. I have placed the same value in a polypropylene (sitting behind the yellow one) on the board to give you an idea of the "dimension" problem I was talking about.



Obviously this won't fit "comfortably" inside the X-Can V2 (or V3) but it's "doable" if you're prepared to funky angle it or mount it elsewhere on the board.

Another thing you can try is to bypass the existing film caps (the yellow polyesters) with a small value polypropylene on the underside of the board (say a 220pF value) this can be quite effective but is really a case of suck it and see....... you won't do any harm giving it a go.


470nF polyester bypassed with a small value polyprop (polyprop fitted in parallel with the polyester)

There are times when you can comfortably fit polyprops on the board and this is one of them:

[nonameleft]

I know this is a very old tread but the topic seems right.

I was just wondering whether the 100u/50V rated electrolytics really belong to the psu as they are named C 105;105;204;205. The psu-caps are named C 1;2;3;...
This might be a reason for the different voltage rating, too.

What values do the ceramic caps C 107;109;207;209 have.
Printing says 3.3 underlined and a black dot on C 107/207 and F 47J also underlined but without the dot for C 109/209.

470n and 1u MKPs should fit when mounted vertically but do I have to expect any interference issues caused by the longer (30mm) wire at one side of the cap?

Many questions, thanks for your answer

Severin

[nonameleft]

I just found the schematic of the x-can v2 solderdude posted here,
may I take the values of this schematic (3.3pF and 47pF for the ceramics)?
The ceramic caps at the input (C101/201) have 220pF in this schem, but I think I´ve read something about those caps having 100pF in the v3, is that correct ?
Maybe it´s worth changing all those ceramics into micas, isn´t it ?

Severin

[nonameleft]

nobody out there, who wants to help ?

[PinkFloyd]

Jan 18, 2013 19:05:54 GMT nonameleft said:

nobody out there, who wants to help ?

You seem to have answered your own questions..... do your own thing and then report back, that way YOU will be the one who's doing the helping You don't need to be spoon fed, you've got the gist

[XTRProf]

It's not correct that nobody here wants to help. For me I'm so busy with my transport biz that I hardly have time here from Mon to Fri. There are also those who have not seen your queries or know how to answer them.

Anyway, all ceramic caps are rated at pf and usually can take high voltage to about 200v and thereabout. For me, I will change all the ceramic to mkp or mks as they are the best in terms of sound or technically against the engineers advice. If you have the cash, can find the correct capacitance and have the space teflon caps will even be better technically although subjectively I will not use all teflon but a mix. We don't want to be stuck with the icy teflon sound, right? I'm a more subjective audiophile than an objective one. Also, don't worry about the voltage rating. It's alright to be higher than lower.

[Deleted]

It's not correct that nobody here wants to help

The members that do have the MF HAs seem to have mainly the V1 and V2.

[nonameleft]

I´m sorry, I didn´t want to attack anybody here at all.
Thanks for your help, I can see more clearly now. So I will try something and report here afterwards.

Cheers
Severin

[nonameleft]

well, I have just finished upgrading my v-3. Thats what I´ve changed:
-replace 1000uF and 2200uF psu-caps all with 1800uF Panasonic fm; unfortunately there are no larger 35v rated Panasonic fms according to the datasheet
-replace 4 100uF/50v caps with panasonic fm
-remove the input electrolytics
-replace 4 output-caps with 2 470uF frolyt eksu and bypass them with 220nF polyester types
-replace all ceramic caps with silver mica types
-replace those yellow film-caps with high quality polyester types
-also I tried fitting heat-sinks to the output-transistors but the bolts were too tight, so I gave up as I was afraid of destroying sth.

I am really happy with the result. I got rid of the annoying treble with my K701 and the improvement in the sonic department is awesome.

Cheers
Severin

[nonameleft]

Hello again,
I would like to try out some schottky diodes instead of the standard 1n4007 but there are no 1000v/1a rated schottkys in DO201-package. The highest rating I could find was 100v/3a in DO201.
Actually, 100v should be ok as the psu provides only +-12v. Doubling the voltage would rise the level to app. 70v. So 100v/3a will be fine, won´t it ?
Next question: Where did MF hid the 8th diode ? The uf4007-kit comes with 8 diodes, but I always count only 7 iodes when opening my v3.
Thanks for help,
Severin

[PinkFloyd]

May 19, 2013 15:29:06 GMT nonameleft said:

Hello again,
I would like to try out some schottky diodes instead of the standard 1n4007 but there are no 1000v/1a rated schottkys in DO201-package. The highest rating I could find was 100v/3a in DO201.
Actually, 100v should be ok as the psu provides only +-12v. Doubling the voltage would rise the level to app. 70v. So 100v/3a will be fine, won´t it ?
Next question: Where did MF hid the 8th diode ? The uf4007-kit comes with 8 diodes, but I always count only 7 iodes when opening my v3.
Thanks for help,
Severin

The 100V diodes will be fine I always throw in a spare diode incase you lose one