[tubesforever]

Around the new year I came across my LCR meter and decided to test out the newest 0.047 and 0.001 uf caps I ordered from Russia.  Well these were all over the map.  I matched these all up and decided I should replace my RIAA caps with something very close matched.

Also, if you purchased some of these K40Y9 caps from me and have not used them yet, send them back and I will close match these for free.

When I measured the PIO RIAA caps I have been using for a while I have to say they were further out of spec between the pairs than I would care to admit. 

BTW if you already have these soldered in, just let me know.  I will send you a close matched pair.  Just solder in the new matched pair and return the used caps back to me.

Hope everyone is having some fun this weekend spinning tunes and enjoying some music!

[NicktheKnife]

I bought a lot of 12 of the K42Y-2 0.1uF PIO caps from ebay.  I was planning on using them in my Piccolo in place of the polyprops.  I'm not sure how to orient them.  There is no + or - identification.  Also,  How do I check them for matching? 

[tubesforever]

You need a meter to read capacitance.   Of your 10 caps you should be able to pair them up and run one left and one right channel.  This way each channel has a more balanced sound quality.

What was hurting my Cornet 2 is that one cap was 0.0456 and the other was 0.0478.  So they were so far out that tube rolling could not be predictable.  The important thing is not the absolute value, that can be +/- 5 to 10%.  The critical issue is to get them close matched so that tube rolling can provide repeatable and consistent results.

If you don't own a capacitance meter and don't want to fork out 35-50 dollars to buy one, just ship the caps to me and I will mark each one for you and send them back to you.  Just pay the shipping!

It would be my pleasure to help you with this.

Cheers!

[NicktheKnife]

 I only have a voltmeter that reads volts, amps and resistance.  Do some Fluke meters have capacitance options?   If there is, I may be able to borrow one.  If not then I will take you up on your offer.   Also, as I said before,  there is no + or - marking on the caps so I'm not sure which way to orient them on the board. 

[tubesforever]

Sorry, I forgot to answer that part of your question.  Many Flukes only do the resistance and voltage stuff.  I have one meter than runs from 2uf to 0.000001uf in range +/- 5%.

Since I am matching pairs on the same meter I can guarantee consistency even if my meter runs slightly different in absolute measurement than someone elses meter.

On K40Y9 caps and on the FT-1,2 and 3 caps the writing orientation follows the windings.  So reading left to right  the left side will be the inner winding and the right side will be the outer winding.

I have oriented my caps both directions on my Hagermans with zero difference.  It might be a big deal with some caps but not with the Russian caps.  I think the heavy aluminum casings are there to provide shielding from EMI since these were used in mil spec applications.   

[NicktheKnife]

Thanks alot,  that explains it for me.   If I can't find a meter that will read capacitance then I will get with you about reading my caps to find some matched pairs.  Thanks again.

[Brinkman]

Tubes,

You might also want to look into getting an ESR meter to disqualify caps of matched capacitance but out-of-spec equivalent series resistance. Another idea is to look at the mathematically exact cap and resistor values in the RIAA curve and see if non-standard cap or resistor values might be more ideal. If so, your meters would be an excellent tool for "optimization" of the anti-RIAA EQ in your phono stage. Just thinking out loud here.

[tubesforever]

Brinkman, this is actually a good idea.  I have no idea where the esr variance might be with a K40Y9.  Hopefully it is closer than their manufacturing tolerances.

My FT-3 Teflons measure really close in uf values ...Only the 0.47 uf seem to head off center and I can match these up for folks as well. 

If I am not careful, by this time next year I will have mounted a switch for optional EQ's on my C2.  It would not be terribly hard to perform this feature.  I just don't know if it would introduce more noise to a totally silent platform. 

Cheers!

[Brinkman]

I have no idea where the esr variance might be with a K40Y9.  Hopefully it is closer than their manufacturing tolerances.

My FT-3 Teflons measure really close in uf values ...Only the 0.47 uf seem to head off center and I can match these up for folks as well. 

I got the "blue ESR meter" kit which is really simple to build. I can't recall exactly how the PIO caps measure, but it wasn't abnormal. I'll check when I get home. The FT-3s, on the other hand, have unusually high ESR. Like, by a magnitude of ten. I haven't removed the outer casing to see if it reduces the ESR, but I have a hunch that's where it originates...