Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: daveyajd on December 04, 2019, 08:33:35 pm

Title: Cap foil direction
Post by: daveyajd on December 04, 2019, 08:33:35 pm
Hello all,
I try to orient my caps correctly with the outer foil. My problem is that I don’t really know how to figure out which direction is “most ground” in my build. I am finishing up my Lightning build and it is the same basic layout as Sluckey’s here:


https://el34world.com/charts/Schematics/files/Sluckey/Matchless_Lightning.pdf (https://el34world.com/charts/Schematics/files/Sluckey/Matchless_Lightning.pdf)


Thanks for any help.


Aaron
Title: Re: Cap foil direction
Post by: sluckey on December 04, 2019, 09:03:39 pm
I line them up exactly as they are shown on the layout. Makes it easy to read the values.   :icon_biggrin:
Title: Re: Cap foil direction
Post by: dude on December 04, 2019, 09:59:58 pm
There is a way to find the ground side, google search a YouTube on that. I can’t remember the builder that showed how to build a box and test each coupling cap. But l do what Sluckey does, my amps are pretty quite.
Title: Re: Cap foil direction
Post by: Willabe on December 04, 2019, 10:43:34 pm
From Aiken Amps web site;

https://www.aikenamps.com/index.php/where-to-connect-the-outside-foil-on-capacitors
Title: Re: Cap foil direction
Post by: tubenit on December 05, 2019, 06:01:01 am
Do you look in ARCHIVES?   Did you do a "search" on the forum?

As an FYI, some of the most repeated questions on the forum are answered in some detail and those answers are in ARCHIVES.

There's quite a bit of information with photos on how to do this right here in ARCHIVES:

http://el34world.com/Forum/index.php?topic=11427.0

And 3 more pages over here:  https://ampgarage.com/forum/viewtopic.php?f=4&t=24654

My experience is that it makes a significant difference in higher gain amps.

With respect, Tubenit
Title: Re: Cap foil direction
Post by: d95err on December 05, 2019, 08:55:54 am
I also line up caps to make it look nice and readable. Don’t care about outer foil.
Title: Re: Cap foil direction
Post by: silverfox on December 05, 2019, 08:55:42 pm
Enter Mysticism.


Sorry but in my analysis and attempts to determine the foil side of the capacitor I've found that it makes no discernible difference. Aside from the builder, who in the audience would know any difference. Anyone advocating otherwise should do a blind test and ask an independent listener if they can tell the difference.


Like this:


Title: Re: Cap foil direction
Post by: BobSmith on December 12, 2019, 10:34:29 pm
I line them up exactly as they are shown on the layout. Makes it easy to read the values.   :icon_biggrin:

Doesn’t the schematic quoted above make the designation?  Curved side of capacitor symbol is the outer foil isn’t it?
Title: Re: Cap foil direction
Post by: sluckey on December 13, 2019, 07:52:23 am
I line them up exactly as they are shown on the layout. Makes it easy to read the values.   :icon_biggrin:

Doesn’t the schematic quoted above make the designation?  Curved side of capacitor symbol is the outer foil isn’t it?
That's just the way I draw a schematic. I usually put the curved side toward the more negative dc potential, even for disc caps which don't have an outer foil. Looks good on a drawing. But that has no relationship to outer foil on the actual capacitor. I'm very fond of these caps. Tell me, which is the curved side? Which is the outer foil side?    :icon_biggrin:

(https://hoffmanamps.com/MyStore/catalog/images/IMG_7957.jpg)
Title: Re: Cap foil direction
Post by: Ed_Chambley on December 13, 2019, 09:36:54 am
I line them up exactly as they are shown on the layout. Makes it easy to read the values.   :icon_biggrin:

Doesn’t the schematic quoted above make the designation?  Curved side of capacitor symbol is the outer foil isn’t it?
That's just the way I draw a schematic. I usually put the curved side toward the more negative dc potential, even for disc caps which don't have an outer foil. Looks good on a drawing. But that has no relationship to outer foil on the actual capacitor. I'm very fond of these caps. Tell me, which is the curved side? Which is the outer foil side?    :icon_biggrin:

(https://hoffmanamps.com/MyStore/catalog/images/IMG_7957.jpg)


Send me 50 or so and I will check them for you.  I will keep them, but I will let you know which side is the outer foil.  A friend of mine dropped off his Fargen ole 800 which is a single channel 2204.  No sound, just quit at turn on.  I pulled all the tubes and have high voltage without any voltage drop. I loaned him the one I built because having 443VDC in v1 plate just sounds like whatever is wrong, I would rather mark caps.  Tubes are good.  Most of the time tubes will fix an amp, but noooooooooooooooooo!


I don't really concern myself with this, but if it has a stripe like a SoZo cap I will put them in as others suggest.
Title: Re: Cap foil direction
Post by: sluckey on December 13, 2019, 11:18:01 am
Don't need'em marked. I already got a good system.  :wink:
Title: Re: Cap foil direction
Post by: mresistor on December 14, 2019, 05:45:16 pm
this subject reminded me of this,,     










Title: Re: Cap foil direction
Post by: shooter on December 15, 2019, 09:09:43 am
 :laugh:

that's cheating, you can see it, to really understand blindfold yourself, rap up some tamales and listen  :icon_biggrin:
Title: Re: Cap foil direction
Post by: mresistor on December 15, 2019, 09:21:16 am
:laugh:

that's cheating, you can see it, to really understand blindfold yourself, rap up some tamales and listen  :icon_biggrin:

do the tamale rap..
 :laugh: :laugh: :laugh: :laugh: :l2: