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Old 5th May 2008, 06:57 AM   #401
dweekie is offline dweekie  United States
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Dave, did the Copper Obbligatos ever get tested? I saw them mentioned on the first post, but I don't remember them being used.
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Old 6th May 2008, 05:45 PM   #402
Davet is offline Davet  United States
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Default 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.
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Old 10th May 2008, 04:57 PM   #403
Davet is offline Davet  United States
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Default 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.
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Old 11th May 2008, 06:12 AM   #404
soongsc is offline soongsc  Taiwan
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Default Re: Capacitor Information

Quote:
Originally posted by Davet
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?
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Old 11th May 2008, 06:34 AM   #405
Davet is offline Davet  United States
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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.
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Old 11th May 2008, 09:24 AM   #406
joemana is offline joemana  United States
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Default Re: Sikorels

[QUOTE]Originally posted by Davet

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
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Old 14th May 2008, 01:03 AM   #407
Davet is offline Davet  United States
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Default 100 Watt Bulb

Thanks for the tip. I will give the bulb a try. I really wanted to test the 220 MFD cap. I have a few caps I am currently testing which I have to report on before getting back to that.

Again Thanks!
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Old 18th May 2008, 10:20 AM   #408
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are there any difference between BG N and BG NX for same value
are the latter better
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Old 19th May 2008, 08:02 PM   #409
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Default Re: Bypass Cap Phase III

Quote:
Originally posted by Davet
I then switched in the 0.1 f 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 f 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.
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Old 20th May 2008, 12:08 AM   #410
soongsc is offline soongsc  Taiwan
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Where can Flourinert be bought?
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