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Old 20th May 2008, 12:27 AM   #411
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Quote:
Originally posted by soongsc
Where can Flourinert be bought?
It's made by 3M, which makes several different types with different boiling temperatures and dielectric constants. FC-72 is probably best, having the lowest K of 1.75. FC-84 is second best with a K of 1.8.

Also FWIW, FC-72 has a lower viscosity, lower than water at 0.64 centipoise (water = 0.89 to 1, depending on temperature).
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Old 19th June 2008, 04:06 PM   #412
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I found a bit of a bargain on ebay: 4.7uF Russian K72 teflon caps. Only one was listed for sale but I pestered the seller and he managed to find me another three. Two measure 4.86uF and 4.87uF so I've wired these up for a trial.

The Epcos MKV should give an impression of size...
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Old 19th June 2008, 04:11 PM   #413
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The caps are connected between my dac and grounded grid pre, so I can't comment on suitability with tripath kit at this stage.

I've previously used K72 and FT-3 0.47uF caps (paralleled up to give around 2uF). In comparison these seem to have far more warmth and colour, which could be due to the increase in capacitance.

They don't seem to highlight the top end as much, although this could be because there is more going on down below. I can't criticise the HF though - everything is very clean and focussed, just not as pushed forward as with the smaller caps.

I will run them in then compare them to the MKVs.
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Old 23rd June 2008, 10:33 PM   #414
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has anyone tried the Mundurf silver oil?
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Old 24th June 2008, 09:23 PM   #415
dweekie is offline dweekie  United States
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Quote:
Originally posted by playntheblues
has anyone tried the Mundurf silver oil?

Check this out.

http://www.head-fi.org/forums/f21/or...thread-284863/
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Old 25th June 2008, 10:20 PM   #416
KT is offline KT  United States
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Default Re: Sonicap

Quote:
Originally posted by Garytr
...The RWA used Jensen PIO caps and now has "new PIO input caps of an even higher quality". Anybody know the cap? They still look like Jensen, but foil and value could be different. The Jupiter beeswax is another option. A tube preamp will also be added.
I followed the RWA Sig 30/30.2 reviews with some interest as that amp is just the thing floats my boat.

I wanted to buy one, but you know how it is in this economy - too much to spend on food, gas, and mortgage to spend on more gear, despite how good it is. If I hadn't already accumulated some really good kit over the last decade and a half, I probably would have picked one up right away, though.

Looking at the inside pix on the 6moons.com reviews, I wonder if the "new" Jensen caps are, in fact, new or proprietary, or if they're just the same copper foils with the plastic wrap removed.

I know there's a lot of strong feeling about the cap skinning issue, so let's not get into any arguments. I, for one, have noticed differences when I skinned caps in various locations in a variety of gear. Suffice it to say, sometimes the effect was significantly beneficial and many times there was no audible effect at all, so I don't think I'm just hearing improvements because of wishful thinking.

Anyhow, I have some of those same Jensen copper-foil-in-oil caps in coupling positions in an Audio Note Kit One amp, and I've observed that the orange color of the cap comes from an extremely tight, translucent, thin, tough plastic that's wrapped around the aluminum body of the cap. The plastic is so tightly wrapped that you might mistaken the surface of the cap as orange anodized aluminum until you look more closely.

I noticed that the new caps in the RWA Sig 30.2 still look like the Jensen oilers, but the surface seems like raw aluminum with no plastic on it (the RWA sig 30 had the orange Jensens in them). So I wonder if these caps might not just be the same ones with the plastic removed. I know Vinnie is keen on tweaking and optimizing his amps for best sound, so maybe this is one of those small tweaks that add up to big refinement?

Well, I don't know. Just speculating. I'm not aware that Jensen released any new kind of signal caps recently. Short of moving up to the Jensen silver foils (seems unlikely given the price), I'm thinking Vinnie must have modded the existing copper caps or had Jensen wind a proprietary cap for use in the Sig 30.2.

My Kit One has been out of commission for years, now, so I can't run a test on it, but if you're adventurous, skinning the Jensen copper foils may be something worth trying.

Great discussion here, btw. Has anyone tried using the TRT Dynamicaps? I like these a lot in my preamp.

Best,
KT
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Old 2nd November 2008, 06:48 PM   #417
Renron is offline Renron  United States
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Jumping in here kinda late, and admittedly not having finished reading all of this thread....(still on page 8)
I have found another great cap shootout.

Here is a snippet ripped straight from this site:
Linkey to cap shootout

It may come as a surprise to some, but REL (Reliable Capacitor) and ASC (American Shizuki Corporation) are among the few companies that wind their own capacitors in their own facilities. Most boutique American brands are actually fabricated by RTI Electronics of Anaheim, California. The Auricap is simply their house cap rebranded with different leads and wrappers. They also boast of making the Cardas cap and, based on appearance and quality of construction, are probably the OEM for the VCap TFTF (on dedicated equipment--not their regular line), as well as the Hovland Musicap, SoniCap, and many others. While the VCap OIMP bears a strong external resemblance to those made by Arizona Capacitor (formerly WestCap) in Tucson, VCap said specifically that their products are not rebranded "house" caps, but their own unique designs. The ASC X300 was relabeled and sold as the original TRT DynamiCap (we have examples on hand with both imprints on the wrapper), but current production seems to be by another firm. In Denmark, Jensen rolls their own, but they are also the OEM for Duelund. For many years, Jensens were also relabeled for Audio Note UK and sold at much higher prices under that brand.

I'm going back to read page 9 now.
Thanks for everyone's hard work, it is appreciated!

Ron
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Old 7th December 2008, 01:46 AM   #418
Davet is offline Davet  United States
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Default Another Cap Shootout

This link addresses a number of capacitors not otherwise addressed within this thread. A few of the capacitors that were tested within this thread were included in the article and the author reached similar conclusions.

Capacitor Musings 2 Article

The author attempted to assemble the best combination of capacitors to suit a musical taste. I think most who have followed this thread will find this particular article insightful.
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Old 7th December 2008, 04:59 AM   #419
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Default Capacitor Musings Shootout Part 1

This is the first Capacitor Musings article.

Capacitor Musings 1 Article
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Old 6th September 2009, 11:56 PM   #420
m1ke is offline m1ke  England
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Quote:
Originally Posted by Bobken View Post
Hi Dave,

It is often a bit dangerous to say which caps are better or always preferred, as this can vary a bit with applications, and there are different attributes to them all which may or may not suit a particular application.

However, by far the most transparent and seemingly neutral-sounding (which I find hard to identify in a direct comparison with a straight wire) are the Teflon V-Caps. Probably second in my usual choice would be the Teflon film MIT Exotica TFT, and then some other no-name Teflons I have tried.

After that, and a bit lower down the 'goodness' scale would be MIT RTXs (mentioned before) which are polystyrene and tin foil, but they have this unusual internal makeup of 10 individual caps in parallel. Mundorf Supreme Silver/oil are about in the same league as these MITS, but I have not done a true side-by-side comparison between these and RTXs in any circuit (yet!), so I cannot state any clear preference.
I used to purchase RTXs by the hundred, so I still have a lot of these to play with until they get used up!

Some non-magnetic silver-micas are good for low (pF) values, especially as they are virtually non-inductive giving a good HF performance, and they are good for RF circuits.

Then my ranking for 'non-specialist' caps is much the same as I discovered well over 30yrs ago, although I don't use these nowadays, unless for some obscure reason there is no alternative.

Polystyrene (the extended foils are usually better), Polypropylene, Polycarbonate (hardly ever seen nowadays), and lastly Polyesters.

I don't share the apparent enthusiasm that others do for Auricaps, unfortunately, and I think this is due to being made from Polypropylene. The Polypropylene caps I have tried are all generally too 'coloured' and lacking in overall transparency for my tastes, but Auricaps have a newish Teflon film cap in their range, which I guess might be quite good.

Regards,
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