[markC]

I'm thankfull for the many hours I'm sure it took to compile this info. After viewing this and Humble's site, I was inspired to try some Jantzen Superior caps. Mainly because they were favourably reviewed, but also because they're inexpensive.
I'm quite satisfied with them. They have a nice balance top to bottom. These caps are encased in a thick, (what appears to be aluminum), cover under the tape. The ends are conductive so beware!

[markC]

Good point, Frank. I always test my caps b4 I install them to be certain that they are the value that they say they are. I find that most measure higher than stated, but always with in their rating spec.

[Bill Baker]

Over the past few years, I have done 'measurement' test on various capacitors prior to 'listening' test. This included many hours on the function generator and starring at a scope. My test were performed using an extremely simple 12AU7 tube [gain stage] that I designed specifically for testing capacitors with few variables. All capacitors were the same value and measured to within 1% (well within range for such test). All capacitors were run in the circuit for 100 hours prior to starting the testing procedure. A few were tested before and after burn-in to settle personal curiosity.

 I did not and will not post my results of this testing as it was performed for personal evaluation, development and voicing of our products. Most of the test were inconclusive as they did not indicate why a particular capacitor sounds the way it does. The only aspects that could be measured with any real science was roll-off at frequency extremes and 'noise' that could be seen due to inferior design and/or materials used in the manufacturing of the capacitor.

 In the end, I ended up voicing our products based on some of the information taken from these test but more-so by listening.

This is a very daunting experiment that in the end, only proved you cannot always  hear what you measure.  Or to put it another way, you cannot always measure what you hear.

[dweekie]

Any more caps on the burner, JonL?   

I find merit in this thread since it mirrors and solidifies experiences I've read from many people in various other forums.  A large collective set of subjective opinions that coincide can turn into an objective measurement..... There is probably a reason oil caps are very popular, and I have doubts that they measure better than most dry film.  I'm not so sure accurate reproction leads to desired reproduction, but I'll leave it at that since this should really have a topic of its own.  JonL deserves this thread for himself 

[Jon L]

Any more caps on the burner, JonL?   

I find merit in this thread since it mirrors and solidifies experiences I've read from many people in various other forums.  A large collective set of subjective opinions that coincide can turn into an objective measurement..... There is probably a reason oil caps are very popular, and I have doubts that they measure better than most dry film.  I'm not so sure accurate reproction leads to desired reproduction, but I'll leave it at that since this should really have a topic of its own.  JonL deserves this thread for himself 

I've got some interesting caps on the horizon, one being paper-in-wax tin-foil (not Jupiter) and polyester tin-foil (which is rare). 

I'm probably going to need to sell off some caps that I have multiples to finance future experiments.  I can't believe how much $ I've spent so far. You can be sure AudioCircle will house those ads when time comes vs. you-know-who 

[markC]

Measure them..yes, and as long as they're within 2% of each other, (stated value), solder them in and listen. They either sound same, better or worse than the last pair. Each brand will have their own impact and you choose which one rings your bell.

[jules]

I can't believe how much $ I've spent so far.

The mind boggles  . Thanks again for putting so many caps to the test, it's a great resource, for some of us 

Jules

[myself]

thanks.

i love the sound of musicap too!!!

[myself]

Wow, such passionate arguments on both sides 

My impetus for all this was really the *one* question to answer:  I had my beloved tube amp(s) sitting in front of me with coupling capacitors, and I wanted to find the replacement capacitors that would sound better/best to me.

Dear Jon,

Thanks for your hard work...i spent an hour reading them myself...in your first post of this thread, you said you had hovland musicap for comparison, but so far i haven't seen any write-up on hovland...please kindly write something on hovland...especially please compare hovland to V-cap, Mundorfs and Jansen...i'll appreciate it very much

thanks again

[Quiet Earth]

What you see is my DIY capacitor burn-in setup w/ resistor and *some* of my caps.



______________

From the picture it looks like your burn in fixture is comprised of a cd player on repeat feeding an integrated amplifier. The large (speaker level) music signal from the amplifier is then sent through the capacitors and into a dummy resisitor to ground. (Whew!)

I'm wondering if the lack of high voltage DC applied to one side of each capacitor would negate some of the normal burn in effect that a new capacitor would get inside a real amplifier. I like your idea for a burn in fixture though . . . . very clever!    It just lacks the high voltage DC. Or does it?

BTW, great job putting all of this together. Thank you very much for sharing all of this. Now, someone just needs to donate a set of Audio Note silver foil mylar in oil caps to complete your experiment. I'd send you mine but I would go through serious withdrawals while you have them.

Thanks again for the excellent thread!
 

[myself]

The silver/oils at 1 uF are $54.57/each unfortunately.

 Jeff over at Sonic Craft sells the 1uF Silver/Oil for $47 ea. He is also having a clearance on the SIlver/Gold if you want to spend a little more ($73 ea.)

http://www.soniccraft.com/mundorf_capacitors.htm

holly cow there's a 20% discount on many cap!!!!

[kyrill]

From the picture it looks like your burn in fixture is comprised of a cd player on repeat feeding an integrated amplifier. The large (speaker level) music signal from the amplifier is then sent through the capacitors and into a dummy resisitor to ground. (Whew!)

I'm wondering if the lack of high voltage DC applied to one side of each capacitor would negate some of the normal burn in effect that a new capacitor would get inside a real amplifier. I like your idea for a burn in fixture though . . . . very clever!    It just lacks the high voltage DC. Or does it?

BTW, great job putting all of this together. Thank you very much for sharing all of this. Now, someone just needs to donate a set of Audio Note silver foil mylar in oil caps to complete your experiment. I'd send you mine but I would go through serious withdrawals while you have them.

Thanks again for the excellent thread!
 

Hi QEarth
input coupling caps and caps in Xovers normally meet since their insertion very low DC levels (few mV)
and in my DEQX digital preamp the DC before the output cap is 1volt.
in tube preamps output caps may meet many volts DC

[Quiet Earth]

in tube preamps output caps may meet many volts DC

Yes, and in tube amplifiers between the driver tube and power tube too, like the ones used in this test. In my own SET amplifier, the capacitor sees more than 300V DC.

I don't know if this has any real meaning or not. I was just curious as to how much the DC had an effect on burn in.

[Brown]

Well insatalled some Teflon V-caps in my SET. Needed only two Breakin was 500 Hrs. With now about 750 Hrs they are still changing. Darn thid is annoying. Do these caps ever break in ? A note to the manfs. BREAK IN THE CAPS AT THE FACTORY. IMO its torture using our NOS tubes and wasting over 500 hours.
   Would a cable break in device be suitable to break them in. Not sure if I prefer the V-caps to the Auri caps they replaced. Its been such a long time since the Auris were in I just cany tell. Quess its time to put the Auris back for a listen. I'll say one thing though the clarity has improved and the imaging is superior. Maybe a bit to smooth on top though.
  Am I loosing it or what ?
   

[rha61]

Hi Jon L

thank you for these great reviews
i've the same result as you with some caps i've tried ( K40 , K72 , Mundorf ...)
what about K75-10 , very nice caps ?

[Jon L]

IMO its torture using our NOS tubes and wasting over 500 hours.   

Do *not* use NOS tubes for burning in!

Anyway, here's a burn-in device I saw on the net some time ago that does apply DC to the caps and can burn in multiple caps at the same time.  For the adventurous, it should be easy to build by looking at the picture.

[djbnh]

Well insatalled some Teflon V-caps in my SET. Needed only two Breakin was 500 Hrs. With now about 750 Hrs they are still changing. Darn thid is annoying. Do these caps ever break in ? A note to the manfs. BREAK IN THE CAPS AT THE FACTORY. IMO its torture using our NOS tubes and wasting over 500 hours.
   Would a cable break in device be suitable to break them in. Not sure if I prefer the V-caps to the Auri caps they replaced. Its been such a long time since the Auris were in I just cany tell. Quess its time to put the Auris back for a listen. I'll say one thing though the clarity has improved and the imaging is superior. Maybe a bit to smooth on top though.
  Am I loosing it or what ?
   

No need to be Old  School. Try using the Isotek System Enhancer CD - works very nicely / in record time. You can copy the CD to tape, and simply have the tape play over and over and over and over and ....

I just used it to burn in new crossovers with some none-too-small caps.

[Brown]

Thanks Jon. That looks fairly simple to make. djbnh have it thank you and yes it is quite affective.

[myself]

nice to combine with http://www.tempoelectric.com/caps.htm
to get triangulation in acquiring data

Triangulate?  More like quinteplate.  Just when you thought VCap Teflon can do no wrong, you can read something like this for contrarian views:
http://www.sixmoons.com/audioreviews/caprolling/caps.html
 
Another cap comparison I mostly agree with is also here:

http://www.ecp.cc/cap-notes.html

There are others, but really, there is nothing like first-hand experience when it comes to caps 

thanks for these wonderful reviews with these good links....however, do you think you will write a review on Hovland musicap?

thanks for the hardwork that's very helpful for my modification of equipement

[jrebman]

John L,

Thanks for all the great work on this.  I just bit the bullet and read through the whole thing and learned quite a bit.

Just wondering if you ever got to try the Mundorf Silver/Gold and Oil caps yet, and I also believe that the supreme silver oils are actually PIO caps where the silver has been vapor deposited directly on the paper, not a poly cap.  What I don't know is if the Silver/Gold and Oils are the same construction or not, but if anybody knows, it would be good to have that information.

-- Jim