#102 Presence cap

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Colossal
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#102 Presence cap

Post by Colossal »

I did a fair bit of searching and reading, but didn't really find a definitive answer. Does anyone know the type/composition of the 2.2uF presence cap in 102? Based on Tony's layout and what I have read, I thought this might be a tantalum dipped or small film cap of some sort. Any help is appreciated.

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erwin_ve
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Re: #102 Presence cap

Post by erwin_ve »

It think it is a tantalum cap based on this pic: https://ampgarage.com/forum/download/fi ... &mode=view
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Colossal
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Re: #102 Presence cap

Post by Colossal »

Thank you very much Erwin. Yes, that looks like the tantalum form factor. Any thoughts on substituting other dielectrics, or is it better to just stay with tantalum?
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erwin_ve
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Re: #102 Presence cap

Post by erwin_ve »

I only used electrolytic and tantalum on that spot.
It is a easy subtitute to experiment. The tantalum opens up earlier when turning the presence pot clockwise.
Imo both do the job well. Taste differences :D
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Colossal
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Re: #102 Presence cap

Post by Colossal »

erwin_ve wrote: ↑Sat Nov 23, 2019 4:55 pm I only used electrolytic and tantalum on that spot.
It is a easy subtitute to experiment. The tantalum opens up earlier when turning the presence pot clockwise.
Imo both do the job well. Taste differences :D
Interesting. I was thinking of ordering both a tantalum and a non polarized electrolytic, but I have a Solen MKP on hand, so might try it for fun. Thanks Erwin!
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Mr. dB
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Re: #102 Presence cap

Post by Mr. dB »

What's the correct polarity for this position?
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erwin_ve
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Re: #102 Presence cap

Post by erwin_ve »

Mr. dB wrote: ↑Sat Nov 23, 2019 6:10 pm What's the correct polarity for this position?
Minus to earth- duh :)
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Charlie Wilson
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Re: #102 Presence cap

Post by Charlie Wilson »

Hmmm? :D
CW
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erwin_ve
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Re: #102 Presence cap

Post by erwin_ve »

Charlie Wilson wrote: ↑Sat Nov 23, 2019 8:08 pm Hmmm? :D
CW
:D #124 ? Whats the verdict on this one?
One off or also seen in other amps CW?
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talbany
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Re: #102 Presence cap

Post by talbany »

IMO.. There are no accidents goofs mistakes or coincidences when it comes to HAD. 8)

Tony
" The psychics on my bench is the same as Dumble'"
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Charlie Wilson
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Re: #102 Presence cap

Post by Charlie Wilson »

erwin_ve wrote: ↑Sat Nov 23, 2019 11:08 pm
Charlie Wilson wrote: ↑Sat Nov 23, 2019 8:08 pm Hmmm? :D
CW
:D #124 ? Whats the verdict on this one?
One off or also seen in other amps CW?
Yeah weirdo #124 :D This is the only amp I have seen him do it in but I agree with Tony, I think he did it on purpose. It kind of softens or smears the top end a bit when you have the polarity reversed. That cap only sees about .5v of DC and the cap doesn't seem to have a problem with it. I had it that way in my amp for awhile. Easy enough thing to try and see if you like it. I think most people will prefer it the way you suggest with negative to ground.
CW
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martin manning
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Re: #102 Presence cap

Post by martin manning »

Applying any continuous DC voltage in reverse polarity to a tantalum cap is not recommended, as it can be damaged or destroyed. They will stand some AC, but only up to a small fraction of the rated DC voltage. For this application, at only 1 or 2 µF, a low voltage film cap is a good option.
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Charlie Wilson
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Re: #102 Presence cap

Post by Charlie Wilson »

Once again, Dumble doing it wrong. :roll:
CW
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martin manning
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Re: #102 Presence cap

Post by martin manning »

erwin_ve wrote: ↑Sat Nov 23, 2019 3:59 pm It think it is a tantalum cap based on this pic: https://ampgarage.com/forum/download/fi ... &mode=view
Looks more like an aluminum electrolytic to me. It seems too tall and too cylindrical to be a tantalum.
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Re: #102 Presence cap

Post by erwin_ve »

martin manning wrote: ↑Sun Nov 24, 2019 11:00 pm
erwin_ve wrote: ↑Sat Nov 23, 2019 3:59 pm It think it is a tantalum cap based on this pic: https://ampgarage.com/forum/download/fi ... &mode=view
Looks more like an aluminum electrolytic to me. It seems too tall and too cylindrical to be a tantalum.
Martin, maybe, I have some big blue tantalums that are tall as in this pic.
Luckily these parts are cheap and a easy swap for experimentation purposes.
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