[kyrill]

hi
Forgive me that i relatively post a lot the last few times, but it is summer time here in Holland and the papers dont have much too tell except the new price of cucumbers..

I have a bypass capacitor question, : i dont understand how they work, while many are so in favor of it.:

" Vishay Roederstein MKP1837 (a.k.a. ERO MKP1830) 0,01mF MKP 100VDC – 1% tolerance
Technical Specifications: Metallised polypropylene, radial capacitor, designed for LC/RC filter circuits, coupling and decoupling at high frequencies. Very low priced cap.

Sound: I was tipped by Klaus Witte of Germany to try this capacitor as a bypass cap for the Mundorf M-CAP SUPREME. I tried them as a bypass for the tweeter series caps in my Progress speaker and I must say I am very impressed! To get straight to the point they don't change a Supreme into a Supreme Silver-Oil but they really do clear things up. I must admit I was sceptical at first as the value is only 10nF (0,01uF) - and the caps in the Progress are 12,6uF. The difference is most noticeable with classical music but also good quality recordings of jazz and fusion benefit: No change in soundstage width or depth but there is more "concert hall acoustics" that let you get into the recording more. Not as liquid as silver/oil but they take away the "grainy" edge from the Supreme's. A gain in clarity and transparency making instruments better separable from each other, the violins in an orchestra are a group of individual violins instead of one mass. Jazz drum brushes sound more like a brush than a "shush".

Verdict: Can’t live without them! – use them as bypass cap with any capacitor."
Tony Gee  http://www.humblehomemadehifi.com/

However why?
my understanding resembles the next writer JerryS  http://www.10audio.com/

"In the simple first order high-pass crossovers we are using for this capacitor comparison, the value of the single capacitor, together with the impedance of the loudspeaker driver, determines the crossover frequency. An 8 µF capacitor with the 4 ohm impedance of the Magnepan quasi-ribbon tweeter gives a crossover frequency of about 5000 Hz (1/2πRC). A smaller value capacitor (for example, 4 µF instead of 8 µF) will raise the crossover frequency. If we used only the very small value .1 µF capacitor without the 8 µF, we would hear nothing because the crossover frequency is now almost 400,000 Hz. Even a dog would not hear it!

So why use a bypass at all? There are actually components of very high frequencies in some audio waveforms. Some are high order harmonics. If you think of a square wave, the right angles at the top of the wave are extremely high in frequency. Sometimes there are high frequency components in very fast audio sounds, for example, the instantaneous tap of a drum stick on a cymbal. These are the sounds that should be "helped" by including a small-value bypass capacitor in a high pass crossover.

But if the 8 µF capacitor blocks frequencies below 5000 Hz and passes frequencies above 5000 Hz, why do we need what is actually another crossover for the same tweeter, but operating at frequencies already passed by the big cap? I am sure engineers have a very good reason, and a couple of them have tried to educate me on this subject. I respect the science and electrical theory on this subject, and my technical background helps me to understand it fairly well. But there is one small problem: the bypasses all sound bad! They add a quality that at first sounds like an increase in air and detail, but after a couple of hours becomes an intrusive harshness and discontinuity in the upper treble. Remove the bypass: all of the detail is present but without that grating and annoying sound. The high frequencies are cleaner, smoother, and much more enjoyable. It doesn't matter if the bypass cap is Teflon®, polystyrene, or common polypropylene, the results are very similar. And to be avoided"

Is he right?

[rabbitz]

I have a handful of the MKP1837 caps to try one day on speaker crossovers as the comment from Tony Gee caught my attention a while back.

I have noticed this being used in quite a few commercial products and an example is the output caps on a Sony ES series CD player from around 1990. The output caps which are electrolytics are by-passed with a small MKP. So there is something to be gained if manufacturers are using it but others such as Auricap (I think) state it shouldn't be done.

Another with 2 camps.... only one way to find out is to try it.

[markC]

I'd like to give those caps a whirl in my x-overs, but can't find anyone to sell them to me here in Canada. Where did you get yours?

[kyrill]

rabbitz
i can "see" if a non electryt cap bypasses an electrolyt , like in yr example i can imagine that sound maybe bettered, but to bypass another filmcap even a well known boutique cap, i can easier follow the rationale of JerryS

i am in the dark in this
MarkC
for instance http://www.radionics.ie/cgi-bin/bv/rswww/searchBrowseAction.do?D=MKP%201837%20Series%201&Ntk=I18NAll&Nr=AND%28avl%3aie%2csearchDiscon_ie%3aN%29&Nty=1&com.broadvision.session.new=Yes&Ntt=MKP%201837%20Series%201&Ntx=mode%20matchany&N=0&name=SiteStandard&forwardingPage=line&R=1666421&callingPage=/jsp/search/search.jsp&BV_SessionID=@@@@0505192308.1183585977@@@@&BV_EngineID=ccdiaddlgejgigmcefeceeldgkidhgi.0&cacheID=ienetscape
http://www.rs-components.co.nz/1/156309231-CAP-100V-0033UF-MKP1837.html

[slbender]

I've not been a big believer in bypass caps myself, or thick power cables, or silver or OFC cables for speakers or interconnects, but thinking about it, I have to admit, Bypass Caps can make a lot of sense.  As caps get bigger physically, and in value (ie: 12,6uF) they become more and more inductive due to the yards and yards of tightly packed metal foil, which then looks like a small to large pseudo-L, an actual inductor across the larger "C".  Inductors "L" store energy similar to a cap, but clearly 90 degrees out-of-phase with the "C".

So placing the Bypass Cap across the Big Cap, where the Bypass is so much less inductive, its "C" is therefore a whole lot bigger percentage of its total LRC  value.  This small C adds literally nothing to the bigger "C", but that Bypass Cap is also across the pseudo-L of the bigger Cap, and that is where its effects take place.  If the proper value is chosen, the smaller Bypass "C" across the pseudo-L tends to partially cancel the "L" out, or effectively make the pseudo-L smaller.  Thus as a whole, the Cap with the Bypass cap across it now becomes more "C" as some of the "L" is canceled, and this effect takes place in the upper audio range of frequencies.

This isn't a perfect cancellation, and will have less of an effect in caps that are closer to a perfect "C" to begin with.  But it should have a noticeable effect, this type of improvement will also work for electrolytic caps in audio circuitry and for electrolytic caps in power supplies, where the "L" is about ten to a hundred times higher, so possibly a 0.1, 0.22, or 0.47 would be a better value.

A similar metalized polypropylene cap is the Vishay MKP1839, an axial version of the one mentioned, from all specs it should the the equal or equivalent part; I haven't found a US Distributor with stock for those either, so if someone knows of one, I'd like to hear about it.


Steven L. bender, Designer of Vintage Audio Equipment

hi
Forgive me that i relatively post a lot the last few times, but it is summer time here in Holland and the papers dont have much too tell except the new price of cucumbers..

I have a bypass capacitor question, : i dont understand how they work, while many are so in favor of it.:

" Vishay Roederstein MKP1837 (a.k.a. ERO MKP1830) 0,01mF MKP 100VDC – 1% tolerance
Technical Specifications: Metallised polypropylene, radial capacitor, designed for LC/RC filter circuits, coupling and decoupling at high frequencies. Very low priced cap.

Sound: I was tipped by Klaus Witte of Germany to try this capacitor as a bypass cap for the Mundorf M-CAP SUPREME. I tried them as a bypass for the tweeter series caps in my Progress speaker and I must say I am very impressed! To get straight to the point they don't change a Supreme into a Supreme Silver-Oil but they really do clear things up. I must admit I was sceptical at first as the value is only 10nF (0,01uF) - and the caps in the Progress are 12,6uF. The difference is most noticeable with classical music but also good quality recordings of jazz and fusion benefit: No change in soundstage width or depth but there is more "concert hall acoustics" that let you get into the recording more. Not as liquid as silver/oil but they take away the "grainy" edge from the Supreme's. A gain in clarity and transparency making instruments better separable from each other, the violins in an orchestra are a group of individual violins instead of one mass. Jazz drum brushes sound more like a brush than a "shush".

Verdict: Can’t live without them! – use them as bypass cap with any capacitor."
Tony Gee  http://www.humblehomemadehifi.com/

However why?

[rabbitz]

I'd like to give those caps a whirl in my x-overs, but can't find anyone to sell them to me here in Canada. Where did you get yours?

My god... something we have in Oz that Canadians can't get. I usually have to get smick items from PartsConnexion or Michael Percy.

I got mine from RSonline.... part 1666421
http://www.rsaustralia.com/

[markC]

Thanks rabbitz, I'll give it a try if all else fails. How long does it usually take to get your order from parts connexion?

[rabbitz]

1-2 weeks for items from Parts Connexion. There's emails that go back and forth to confirm the order and shipping costs and then they ship.

[markC]

Cool- I'm gonna try, because I've been getting nowhere with rs international and a dutch site that I was referred to.

[kyrill]

to get this particular cap, is that a matter of money?

Isnt it better more homogeneous sound to bypass with that value with the same brand of cap?
If the inductance story is the reason, so the cap is big, why not bypass it with its much physical little sister of 0.01 uF?

[rabbitz]

Most of the caps I use in speakers are Mundorf and in Oz the smallest value is 100nF which is too high. I don't know about other brands but have seen a couple with stupid prices for a 10nF cap. An example is a Solen Tin Foil which was 3x the price of the MKP1837 and any better???

An interesting note in the resellers blurb I have on the Tin Foil is "Parallel a Tin Foil across a larger value capacitor to speed up the overall transient response of a tweeter or midrange speaker."

[kyrill]

i found an ebayshop ( but for Europe mainly, dunno its shipping prices to oz or canada)
http://cgi.benl.ebay.be/ws/eBayISAPI.dll?ViewItem&item=320131357056&ih=011&category=14991&ssPageName=STORE:PROMOBOX:NEWLIST#LIST

vishay R still exist as a company?

[AKSA]

Kyrill,

A few interesting observations about Vishay, who are thriving.

Headquartered in Philadephia in the US, this is arguably the most aggressively run components company in the world.  The company has pursued a policy of acquisition starting in 1985, and beginning with resistor companies Dale Electronics, Draloric Electronic, and Sfernice, realising a dramatic growth within a decade. In the early 1990s, Vishay acquired Sprague Electric, Roederstein, and Vitramon, all very large capacitor manufacturers.

Vishay acquired BC Components (former passive component businesses of Philips Electronics and Beyschlag) in 2002.  This acquisition expanded Vishay’s portfolio of passive components and greatly enhanced its global market position.

They have not been so successful, however, in the Far East and Japan, markets which dominate respectively the computer components and premium quality component spheres.

However, as will be apparent to anyone in Europe, the EU market is 340 million;  the US market, 270 million.  While the US marketing reach is the best in the world, the Euro is now the strongest international currency.  Thailand, where I now have some of my pcbs made, is now setting its prices in Euros, rather than USD, and this clearly tells us something.  If the EU can hold together (and the history of peace in Europe is not a thick volume!) the market there will increase, particularly as the emphasis will be on quality now that China is becoming the dominant low tech manufacturing country; and so Vishay is well positioned to grow significantly within this market with its judicious European factories.  I'm expecting Arcotronics in Italy to fall any moment.  Meggitt (UK) recently acquired Piher-Narcesa in Spain, both are very large manufacturers of potentiometers, but TT Electronics plc (UK), owners of Welwyn and other significant brands, are really the only opposition in the passive components area.

Vishay has a policy of swallowing all competitors then sharply increasing price.  In this modern world of international, atavistic corporations (this is not new, the Dutch and British had multinational corporations in the 17th/18th/19th centuries) it is not surprising that companies on this scale behave as they do!!

Cheers,

Hugh

[kyrill]

thx Hugh
i hope all aggressive (company) strategies fail, unless with integer aims for themselves and the  customer

[markC]

After several e-mails back and forth with RS-Components international, I finally got an order in. Caps are on there way from...England! Shipping costs more than the 10 pieces that I ordered, but will still be around C$50 total. A little pricey @  $5 a cap, but if they do what Tony Gee claims, then they'll be a bargain.

[kyrill]

Jen, Andyr, Hugh, other maestro's

Can i safely put such a vishay 22nF 160V cap parallel to the nichicons ( one for each)  in the power supply board of the AKSA 55N+? And if yes, will it be beneficial sound wise?

[drmike]

what is the part# oe the caps you ordered, web site?
thanks,
drmike

[kyrill]

hi drmike
:Vishay Roederstein MKP1837  ordered at
1) http://stores.ebay.com/Sonicapeurope
but
2) http://www.mouser.com/search/refine.aspx?Msid=61310000&Mkw=MKP1837
has them too

however,
http://www.mouser.com/search/refine.aspx?Msid=61310000&Mkw=MKT1822

seems even to be better in all aspects...
read: http://www.audiocircle.com/index.php?topic=42756.0

[AKSA]

Yes, Kyrill,

You can do this, but the effect will scarcely be audible.

Typically a bypass should be around 1% of the principle capacitor.  In this case, it should be 1uF;  the 150nF I use is pushing the limits of audibility, so I would say 22nF would be very difficult to 'hear' indeed.

Cheers,

Hugh

[ginger]

We talked about bypass caps on an old GK-1 Valhalla thread.

Here is the link:
http://www.audiocircle.com/index.php?topic=3733.msg42423#msg42423

Cheers,
Ian