Duelund JAM paper in oil , Cu foil Capacitors as coupling caps on Tube Amp

On my tube amp from Cary Audio, I have been happily enjoying sound of  Jensen Paper in Oil , Copper foil, Alu Case capacitors ( value 0.22 / 630 VDC ) as coupling caps. I like its lush , liquid sound, not harsh. As they are 9 years in use now, I may need to replace them soon. I just found that Jensen has stopped production so was considering a good replacement to match the sound. I get option of  Duelund JAM paper in oil , Cu foil Capacitors which are at present available at good price ( $45 per pc. ). I like to know if anyone here has used these caps as coupling caps and how is the experience. What change in sound can I expect going from Jensen PIO caps to  Duelund JAM PIO caps?
Or does anyone have other recommendations for substitute of Jensen PIO caps? 
My amp has a small chassis, hence may be difficult to put large caps.
Your views, comments , suggestions are welcome.

Dear @radni : Look, if your amplifier is a true good design and if you are a true music lover and not a hardware lover and before you pull the triger in any of those heavy colored/distorion and expensive caps you name it test these ones:


don’t be afraid or worry with because its price is so low, forgeret. Wima as EPCOS or Vishay are the true standards in the whole industry including audio but the corrupted AHEE teach us to go with the colored ( $$$$$ ) ones and not with a true capacitor.

Do you know that those caps with wax, paper, oil and the like was the ones used when the Radio started 60+ years ago? and only we ignorant/low knowledge about are using the same kind. Why? I already said it: AHEE lessons over the years and unfortunatelly ( including me. ) we all belongs to.

A capacitor is a simple passive devise to design and has an easy job to do: let pass the non blocked signal with out adding distortions or colorations. Why the signal needs wax, oil or paper? ask those expensive capacitor manufacturers that tell you and tell us why. Do you know why? me neither and exist no scientific explanation about any where. ? ! ? ! ? !

You can try, nothing to lost about and maybe you can learn " something ".

Regards and enjoy the MUSIC NOT DISTORTIONS,
Dear @erik_squires : "" They make everything sound the same .""

well if everything means same electronic designs then agree with you.

Wima makes the true job/task inherent to a capacitor and will shows you the real quality performance level of your electronic/speaker designs, that’s why is a standard in the world industry: milatry, aero space, automotive, medical instruments, etc, etc. not only Wima is considered an engeneering standard by the industry but Epcos or Kemet or Vishay too.

I know for sure, because I have first hand experiences, that your statement is untrue and false.

I own or owned Levinson, Classé, borrowed Krell and all use Wima caps and no one sounds the same. I owned too tubes electronics.

Do you think that the next electronics sounds the same? certainly not and are electronics at the very top audio price range and use Wima:



here you can see why Wima is a true industry standard and not because I said it but because those caps have to meets Standards fixed by industry or engineering world associations as IEC:


Vishay is the same:


Now, please post the facts/tests that can attest that the audio signal need wax/oil/paper in the caps or at least measurements of Duelund/Jupiter, Vcaps and the like that proves it.

NO, that audiophile sentence : " I like it " is not not a test but not a fact and has not validity.

You are a gentleman that I think know in deep all my post meaning and knowing that I can’t understand why posted that kind of statement other than laughgin of me. I really don't care if you are making a joke of me, can't disturb me in anyway.

I used teflon Cu V-caps in my input amp and when I tested Wima there believe it or not outperformed the very expensive V-cap teflon Cu.

Same experiences as in my speaker crossovers where I used Duelund, Mundorf, Jantzen Alumen, V-caps, Sonicraft, etc and Wima/Epcos and the like outperformed all those heavy colored and distortion generators name it " boutique caps ": all of them ! ! !

Regards and enjoy the MUSIC NOT DISTORTIONS,
Please show the study where it is shown everything that can be heard is already measured.

You betray your own logic. You insist that differences must be measured by old measurements, but you also claim Wima has outperformed other caps. Based on what, exactly?  So you may use your hearing, but I may not? Double standard. :)

Thank you,

@erik_squires  I'm asking specific measurements coming from the manufacturers and if posible against Wima or the like caps.

In other thread in this forum some one posted how Duelund measured in its caps and resistors and guess what: measured terrible bad and that could explain the added colorations.

MUSIC is accuracy: do you know that?

If your caps are only 9 years old and not showing any leakage or audible effect its unlikely you need to replace them. Unless of course you just want to try something new.
Dear @erik_squires  : "  Please show the study where it is shown everything that can be heard is already measured. "

your sentences makes no sense because you already knew that study does not exist.

Now, does not exist that kind of study does not means some timwe in the future some one could does it if he knows what and how to measures.

Btw, other example of caps that make " everything sounds the same ":


Raul did you buy stock in those Wima caps, just kidding. I understand your philosophy that a quaility design may not or will not benifit from a boutique cap. Some gear the best and easiest way for it to sound better is boutique caps. In my experience I prefer the boutique caps. To the OP I like the Jupiter copper foil for the lush sound, Miflex are cheaper but huge. I don't think 9 years will make a cap go bad. I have a Scott lk48 from the 1960's that sill sound fantastic.

Thanks paulcreed  and jond, for your valuable suggestion regarding checking of life of my currently installed coupling caps. I intend to check for any leakage and measure the value on capacitance meter before going to change them.
I knew that that will be the OP answer/OP because as many of us is a very well trained gentlemans that " eated " what the AHEE teacher gaves all of us.

Maybe for some of you could " sing " as a bad joke but that extremely humble FKP-1 Wima cap outperformed a 100.00 V-cap teflon CU for only 2.00. Unveliable for say the least but things can happens when we try and lear. Not for very one and more important not for bad/medium electronics quality designs..