Jupiter copper Cap breakin?

[TubeDriver]

I'll take a look when i get home but they are the standard old, large, metal, rectangular 600V caps. I tried 3-4 other similar oil caps but this pair sounded significantly better than all the rest. Maybe just lucked out with a cap that matches real well with my system or is just a really nice sounding old oil cap?

That'll work or tune in interstation radio noise if you want to emulate the Hagerman doodad.

What were the original oil caps that you are seeking to upgrade?

[SoundMods]

Let us know what your plate voltage is -- and what the input impedance of the amp. stage you are coupling to.

[TubeDriver]

LOL! Getting old sucks, my recollection of plate voltage was way off.

Single stage 1626 with B+ of 245v, plate load of 5.1K ohms, plate voltage is 170v.

I calculated output impedance at about 1753 ohms. Input impedance is roughly 100k (100k grid resister) although I once calculated it with miller capacitance and I think it was closer to 78k ohms. I just used 100k ohms and got 1.4uF for -3db at 1.5Hz so I rounded up to 1.5uF.

Let us know what your plate voltage is -- and what the input impedance of the amp. stage you are coupling to.

[TubeDriver]

The oil caps are "Gudeman Company" oil condensors.

That'll work or tune in interstation radio noise if you want to emulate the Hagerman doodad.

What were the original oil caps that you are seeking to upgrade?

[SoundMods]

Just a note to say that 1.5-ufd is quite big for 100K-ohm load. At 5-Hz, which gets the job done since you are only worried about a decade higher interaction (50-hz.), 500-nfd (0.500-ufd) will allow things to open up for you by getting rid of unnecessary storage with its baggage known an dielectric absorption (DA) and dissipation factor (DF). Bass? No problem -- you start to roll off at 5-Hz. This value (the nearest standard value is typically 0.47-ufd) can also serve to lighten the load from sub-sonic crap especially when playing LPs.

My secret ingredient is the polycarbonate capacitor paralleled with teflon.

The following link gets you to an offering from Component Research that is one of the finest manufacturers of aerospace and mil-spec components:

http://www.ebay.com/itm/ONE-Component-R ... SwwbdWKikJ

Bypass these with some nice Teflons to get you up to or just past 0.50-ufd and you'll get religion. Even at 0.33-ufd you are at about 5.2-Hz. So the Teflon bypass can be physically small to fit.

Such as:

http://www.ebay.com/itm/5600-pf-600V-Ru ... Swa39UvTWp

These will overlap at around 300-Hz. The composite will provide musicality together with speed and transparency. 100% polycarbonate can be a little soft and 100% Teflon can get glassy. The two dielectrics compliment each other.

[J-ROB]

Gudeman caps can be decent. There is no real ranking outside of performance in situ.

It wouldn't surprise me a bit if they are better than Jupiters in some ways. Why should Jupiter caps be great (think they are electrocube mfr)?

I would put a 1-2uf Russian KBG cap in there if forced to pick something I could snag offa ebay any day of the week.

If it is a CF, parallel a couple low volt 0.25 KBGs...I can slip you 4 if you want to experiment. I have some 2uf KBGs also.

These are not too dark and thick, just right.

Or a Sprague Vitamin Q 196P 0.47-1uf from the obsolete vintage cap sector, still one of my preferred parts after 30+ years of cap swapping.

I'd pay $150 for a cap, but it would have to be delivered by a cute young woman naked except for a fur coat, carrying a bottle of single malt scotch. And I would still demand a 30 day return privilege.

But that's just how I roll...

PS: Have you tried that Gudeman in your furnace?

[TubeDriver]

Thanks for the recommendations. I think I already have some of the low value russian teflon caps. Now that I am thinking about caps again, some experimentation may be in order.

Just a note to say that 1.5-ufd is quite big for 100K-ohm load. At 5-Hz, which gets the job done since you are only worried about a decade higher interaction (50-hz.), 500-nfd (0.500-ufd) will allow things to open up for you by getting rid of unnecessary storage with its baggage known an dielectric absorption (DA) and dissipation factor (DF). Bass? No problem -- you start to roll off at 5-Hz. This value (the nearest standard value is typically 0.47-ufd) can also serve to lighten the load from sub-sonic crap especially when playing LPs.

My secret ingredient is the polycarbonate capacitor paralleled with teflon.

The following link gets you to an offering from Component Research that is one of the finest manufacturers of aerospace and mil-spec components:

http://www.ebay.com/itm/ONE-Component-R ... SwwbdWKikJ

Bypass these with some nice Teflons to get you up to or just past 0.50-ufd and you'll get religion. Even at 0.33-ufd you are at about 5.2-Hz. So the Teflon bypass can be physically small to fit.

Such as:

http://www.ebay.com/itm/5600-pf-600V-Ru ... Swa39UvTWp

These will overlap at around 300-Hz. The composite will provide musicality together with speed and transparency. 100% polycarbonate can be a little soft and 100% Teflon can get glassy. The two dielectrics compliment each other.

[TubeDriver]

I think that is a good point, performace in situ is all that really matters. You really have to just try them in your system. Of course I have also tweaked and tuned my system with the old oil caps in situ, so the new Jupiter caps do not have the benefit of that experimentation at this point.

I remember listening to identical brand caps of different sizes (or voltage) and finding that sometimes they sound very different (and not a simple function of -3db cutoff). The 600v Hovlands sounded a lot better than equal value 400v Hovland versions.

Gudeman caps can be decent. There is no real ranking outside of performance in situ.

It wouldn't surprise me a bit if they are better than Jupiters in some ways. Why should Jupiter caps be great (think they are electrocube mfr)?

I would put a 1-2uf Russian KBG cap in there if forced to pick something I could snag offa ebay any day of the week.

If it is a CF, parallel a couple low volt 0.25 KBGs...I can slip you 4 if you want to experiment. I have some 2uf KBGs also.

These are not too dark and thick, just right.

Or a Sprague Vitamin Q 196P 0.47-1uf from the obsolete vintage cap sector, still one of my preferred parts after 30+ years of cap swapping.

I'd pay $150 for a cap, but it would have to be delivered by a cute young woman naked except for a fur coat, carrying a bottle of single malt scotch. And I would still demand a 30 day return privilege.

But that's just how I roll...

PS: Have you tried that Gudeman in your furnace?

[SoundMods]

Sounds like a business plan for a delivery service -- we can call it NUBER.

That said -- I have on hand two white papers written by Rabid Audiophiles with a lot of time on their hands and deep pockets.

In both cases they tested caps in circuit with an amp set up with clips to make rolling caps easy.

Some of the highly regarded "super audio caps" didn't fare too well. There are a lot of nicely priced goodies on eBay that came out of the cold war that I feel surpass those "audiophile" parts.

Both the U.S. and Soviet military and aerospace establishments required components that had to exceed many requirements that were way beyond typical electronic industry needs.

As it turns out -- that stuff can serve the music. Caps -- resistors -- wire & cable -- and so on. I learned this from John Curl, Pierre Sprey, and Stan Klyne -- the first guys that I know of that realized the potential of those parts in audio equipment.

[Pelliott321]

I have followed Wayne's (SoundMods) advice on caps on a couple of my projects with very good results.
I have not and will not spent much on costly audiophile caps, but all I can say is that Wayne's recipe sounds like music to me.