Tripath Input Coupling Caps

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Copper Obbligatos

I tested them back in the beginning. Without going back through the thread, from what I recall the two Obbligatos sounded very much alike. Then again, that was many caps ago. I can put them back in the test bed to compare, again.

I have developed a baseline since then, and I have a couple of caps that I have yet to test.

The springtime "honey do" list has kept me somewhat busy. I have been just listening to music (other than the test suite) as I try to wind down. I have, primarily, been listening to the baseline, Bypassed BGs, Epcos, and Auricaps. I am always impressed as to how smooth the sound of the Epcos caps are compared to the others.
 
Capacitor Information

While listening to music I have had the opportunity to read a considerable amount of material relating to capacitors, bypassing, and the like. The following two links I have found to be most insightful.

The CapSite is an easier read than ESP Capacitor Characteristics which is very comprehensive and contains in-depth technical detail and explanation for the text contained therein.

The CapSite was a ESP Cap Chracteristc reference article. The references are well worth the time it takes to read and comprehend for those that are so inclined.
 
Re: Capacitor Information

Davet said:
While listening to music I have had the opportunity to read a considerable amount of material relating to capacitors, bypassing, and the like. The following two links I have found to be most insightful.

The CapSite is an easier read than ESP Capacitor Characteristics which is very comprehensive and contains in-depth technical detail and explanation for the text contained therein.

The CapSite was a ESP Cap Chracteristc reference article. The references are well worth the time it takes to read and comprehend for those that are so inclined.
This reading information seems very interesting. I guess that for most people participating in this thread, we all probably have experienced the audibility of various capacitors. Perhaps the engineering issue is how would the audible difference be associated with measurements. I would like to take the opportunity to address some issues to think about:

1. Distortion due to caps have been addressed on not significant in the reference article. However, it did not address the fact that the distortion may be amplified. If we do estimate the amplitude level of distortion and the harmonics, it may reach audible levels.

2. In no place have I seen any investigation of charge density of capacitors and whether it may effect performance. None of the models address this issue either. However, if we look at various capacitors in varying sizes and capacitance, this may become an issue.

3. Are the charge and discharge characteristics of capacitors symmetric? To what extent?
 
You have raised some interesting questions. I, regret, I don't have the background to address them. If anything it would be speculation on my part. There may be readers of this thread that may provide answers or direction for your query.

The authors of both articles welcome queries and comments. They may possibly be able to direct you. Both articles have numerous links regarding capacitance and capacitors. The answers may be buried in those additional articles. If you do get answers to your questions, please post a response here.

The articles gave some foundation to what I have heard and some of the suggested testing topologies that have been offered. A number of things I have been pondering were resolved by reading these articles. While, some other question have arisen in my mind as a result of reading these articles.

This hobby and the quest for knowledge is just fascinating.
 
Re: Sikorels

Davet said:
Any suggestions from readers as to best handle this "fuse/charging" problem would be appreciated .

Dave,

I don't know if somebody already responded to this as I didn't read the whole thread. Just in case you still have a fuse problem.

Connect a 100Watt bulb in series with your fuse and your fuse will last forever.
This was suggested by (if I remember correctly) Thomaselliot, before that, I had blown more than 20 fuses in two months period.

Joe
 
Re: Bypass Cap Phase III

Davet said:
I then switched in the 0.1 ¼f Flourinert cap in addition to the above. This Flourinert cap is a Russian Teflon Cap that has been augmented by Serengetiplains. Initially, it sounded if all the bass had been sucked away. I thought maybe the cap was drawing more "something" and that accounted for the loss of bass. After a couple of hours I noted that the bass was there, but it was not prominent or overwhelming.

After some eight additional hours of listening I can comfortably say that the overall presentation has been enhanced. Everything seems more balanced: bass, mids, highs. The sound stage seems to have gathered considerable depth; more so than anything else I have tested.

My perception of the sound being sucked out was not just my imagination. My wife claimed the stereo didn't sound as loud as it had earlier. This is true, but I know that quiet passages sound "much" quieter. I never alter the volume setting from test to test. There is a certain umph to bass. Vocals sound as if the vocalist is in the room and there is absolutely no sibilance.

This is a really listenable combination. No fatigue at all. Recordings I didn't particular care for before are more than tolerable. They are actually listenable. This comination is squeezing a certain "magic" out of the recordings.

I then switched to a silver mica 0.1 ¼f cap. The bass became more pronounced/louder. Otherwise, everything else seems the same as with the Flourinert.

I thought I would pipe in re the Fluorinert capacitors, having been absent from DIY for some while but again now with time to reengage. The fluorinert capacitors Dave employed in his tests came from experiments I was conducting to design a better capacitor. Fluorinert, as perhaps most on this thread know, is essentially liquid teflon. It was designed primarily to serve as a coolant for mainframe computers, etc. In my search for a better-than-teflon capacitor dielectric, fluorinert had two appealing qualities. First, it is a liquid which, as a liquid, creates a more intimate plate-to-dielectric contact, and possibly allows DA-voltage cancellation due to physical movement at the molecular level. Second, it had an attractive dieletric constant of 1.75 thereabouts, considerably lower (so far as these things go) than solid teflon (= 2.1 thereabouts). In my experiments, I learned that solid teflon actually absorbs fluorinert, and that the teflon expands in this process by some 8-10% without any breakdown in chemical bonds. This expansion of the solid teflon part of the dielectric must tighten the windings, reducing microphony, or so I reasoned. So fluorinert looked interesting.

Fluoriner sounded quite interesting .... only after break-in, as Dave has noted. To my ear, fluorinert was a sibilance killer, and transmitted AC signals with greater resolution than regular teflon caps. My sonic observations correlated with measurements I performed that showed, to my satisfaction, that the fluorinert caps reached max DA recovery voltage with blazing speed, and typically showed an order of magnitude lower DF (almost unmeasurable on my Quadtech meter).

The caps Dave used in his tests are somewhat compromised in that the leads (and FWIW the body) are steel. And also FWIW, lead connections on these Russian caps look to my eye a little iffy. I have created a few porous teflon / fluorinert caps that sound and measure better than these fluorinert-injected Ruskies.

For people wanting an excellent examination correlating capacitor sound with measurements, check out Cyril Bateman's series on the Sound of Capacitors.
 
soongsc said:
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).
 
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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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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Re: Sonicap

Garytr said:
...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
 
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
 
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.
 
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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