Duelund Silver Foil & Wax/Oil Bypass Caps

eriksquires

Member
2013-05-10 4:11 pm
Queue the peanut gallery please! Just thought I would share with you my latest experiments. Warming up in the batter's cage I have a pair of the most rare and almost completely unknown Duelund Precision Bypass capacitors in the 600V, 0.047uF size.

IMG_20160122_112236.jpg

Technically Silver Foil in Wax/Oil only four sizes are available:

600V
=====
0.01uF
0.022uF
0.047uF (measured 0.0475 and 0.0476)
0.1uF

Measured ESR, DF and Q were all below measurement thresholds of my DATS V2.

Back Story
Very few of these have been produced so far. With a retail price around $4,000 / uF they certainly rank among the most expensive caps money can buy.

Hand made in Denmark by blind virgins who were raised in a convent and never been allowed to listen to Michale Buble or Justin Timberlake.

The Spaniards melted down the silver at a temple dedicated to Tlaloc, the Aztec god of Thunder. Shortly after loading the silver onto the galleon the Esmeralda, the ship set sail for Cuba. Before it could reach the horizon out of a calm but cloudy day a wind gust turned the ship almost completely around and that's when lightning hit all four of it's masts simultaneously. The ship was set afire like a four ended candelabra in the sunset. The silver used in the Precision Bypass caps comes exclusively from that wreckage, and when that supply is gone there will be no more.

[IMGDEAD]https://upload.wikimedia.org/wikipedia/commons/thumb/d/d4/Tl%C3%A1loc_3.jpg/450px-Tl%C3%A1loc_3.jpg[/IMGDEAD]

OK, I'm making that up, but that's the kind of back-story caps this expensive should have. They really are pretty rare though.

I'll be using this to bypass the Clarity MR 400V, 4.7uF caps in my tweeter crossover. Previously I had a 0.1uF Audyn True Copper capacitor, which ended up being too bright. I'm still using that cap but elsewhere.

So, to the peanut gallery, just cut and paste your usual comments please, don't bother typing in something original or new.

We'll see how long it takes me to list these caps on E-bay. :)

Best,


Erik
 
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eriksquires

Member
2013-05-10 4:11 pm
I have installed the caps in one of my two speakers. For the curious, the speakers use a Mundorf AMT tweeter and 6.5" Scancpeak revelator sliced paper woofer.

The high pass crossover LOOKS like a third order filter, but it's not. First cap is 4.7uF, second is 10uF.

The prime caps are Clarity MR. The Duelund is bypassing the first cap. The scond cap, at 10uF, is bypassed with a 0.1uF Audyn True Copper foil. The Audyn TC sweetens up the midrange and gives me goose bumps. Not sure if that's more realistic, but it seems I like goose bumps. Who knew?

My initial impressions after 30 minutes of barely being able to sit are mixed. Nothing bad has happened, but I don't yet hear the $200 worth of value.

The most noticable effect is a focus in the strings. You feel on a good recording that you could almost pick the brand of strings being used in the guitar. They become palpable, and high frequencies more open.

But that's it so far. In fact, if all the caps do is make strings so clear it may be a negative. My guest reviewer will be here later today or tomorrow. She has the ears of a 19 year old and can usually tell when I've changed something. Stay tuned. IN case you are wondering, I went around looking for reviews and found zilch, so I have no preconceived notions other than what's on the label.

Best,


Erik
 
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eriksquires

Member
2013-05-10 4:11 pm
48 hours in, and I'm just starting to listen seriously. My guest reviewer, whom I can give no bias to, said "They sound punchier." Well, that's not very useful. My original impressions about strings stand. You do feel as if you can get really close to them compared to before, and there is an appearance of airy high treble appearing. Nothing yet justifies the $200 spend though.

The tweeter is a mid-sized Mundorf AMT extensively measured in another thread here. The prime caps are Clarity MR's. I tried bypassing both with Audyn True Copper caps. The smallest value Audyn TC is 0.1uF. I did not like it bypassing the 4.7. Made the sound seem too bright. The 12uF cap however it was fantastic with. Gave the upper midrange a really nice liquidity. By comparison, the Duelund has extended the apparent treble ever so gently without increasing the volume. Of course, the values are different by half, I have no way of comparing an Audyn 0.047uF capacitor I'm afraid.

If these caps really are phenomenal I may have them in the wrong situation. Sadly I bought as much as I can afford, so I cannot bypass the 12uF cap. Crossover values are approximate, to protect the guilty. If I was a reviewer who considered $16,000 speakers affordable, I'd have happily bypassed both capacitors with Duelund Precision Bypass Silver in wax/paper to the tune of $600, but that's getting into some major bucks for those of us who actually work for our money.

It's also far too close to the cost of prime copper foil caps from Duelund or Jupiter. If some kind soul wishes to ship me a pair of Duelund 0.1uF Precision Bypass caps however I'd be happy to tell them what they sound like. :)

Duelund_Test_Schema.jpg
 
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eriksquires

Member
2013-05-10 4:11 pm
Well, the Duelund bypass caps have been in for 5 days and I am still not really impressed with this application.

I think for my next experiment I may switch altogether to some Jupiter copper foils which I can get for about 25% off and are much more cost effective.

Best,

Erik
 

eriksquires

Member
2013-05-10 4:11 pm
I totally forgot to come back here. In writing in another thread about experimenting yourself being critical to learning and science, I remembered about this thread. To the 4 of you who were reading, I have finished my experiment.

At about 3 weeks and I can call this experiment a total bust. I can honestly state I hear no material benefit to having the Duelund's in the crossover at all. Onto the next speakers! I think the initial effects I heard were probably due to the recordings at the time and poor hearing memory. I'll do one final test, to clip them off and see if my test subject (not a volunteer, countless of hours of helping her write a resume make her participation mandatory now) hears any difference when I remove them.
 
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eriksquires

Member
2013-05-10 4:11 pm
I am wondering however if there is something about break-in time that makes bypass capacitors seem to be more effective at first, but then goes away. I'm hesitant to experiment more on this because the caps I did like, the Audyn True Caps, I really don't want to mess with. :)

But consider. What if the real issue is something odd happens when you add a bypass cap with say different ESR or something. You plug it in, it IS different, and then goes away. You remove it, and of course, you hear a negative difference.... but what if in stead what you are really messing with is whatever it is that is being broken in? What if adding a bypass cap or removing it just causes the prime caps to take a while to adjust, and at the end of the day the bypass caps don't really do anything lasting?

In other words, what if break-in time is real, but the audible benefits of bypassing is not? Too much for my brain.

Just a thought.

Erik
 
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Erik, love your writing style. You sound like a mad man.

Try this;
If you are using a tube amp, have all your 'outer foils' pointing towards the drivers. Often this means the 'writing' on the caps flow to the amps.
If you are using a solid state amp, have all your 'outer foils' pointing towards the amp. This means the words on the caps flow to the drivers.

The peanut gallery may also respond.
 

dallas21

Member
2010-02-23 2:25 pm
Capacitor bypass caps

I have modded Loudspeakers,as well as electronics for close to 20 years .

For this comment below to say the Audyn true Copper bypass cap would or was making the tweeter too bright vs a Silverfoil cap. Anyone knows Silver is far brighter then Copper .especially these Audyn Copper caps I have used these in
As regular coupling caps as well as in my current setup VH Audio oimp main caps
And Audyn True copper For .22uf bypass caps . These caps take at least 150 hours just to settle in ,and will refine past the 300 hour mark .
Just go to Humble homemade Hifi capacitor test and look these up.
Their new True Copper Max cap is slightly better still these caps are every bit as good as The Jupiter Copper ,or Standard Duelund paper oil caps rated over a 12
Where a Solen cap maybe 6-7 ,these are as good as mundorfs best .which I have used ,as well as all of the above. I have these in my Salk Bud Fried tribute
Speakers which use a simple series 3 cap 2nd order Xover , for bass I used the Mundorf Supreme great punch and control . The Vh audio oimp metal used pol paper with the Audyn true copper bring Outstanding results at minimal expense
50% less $$ then the Big name brands .i have had many people complement
The sonics this combo brings .it came with Soken ,Jim Salk will upgrade if requested, I changed yo Mundorf Supreme , the went to the vh,Audyn Copper
Later. Well worth the efforts but you have yo let play for a solid week just to
Get the breakin process going . One more thing matching all capacitors with
1% and using 1% Path audio resistors Jantzen a Copper inductors the imaging
And coherence is palpable timing comes from the accuracy of all matched Xover
Components . Chris at VH audio offers matching to within .5%.
I hope this helps ,it is all well battle tested and proven .
 
Bypass caps humbug

Well, the Duelund bypass caps have been in for 5 days and I am still not really impressed with this application.

I think for my next experiment I may switch altogether to some Jupiter copper foils which I can get for about 25% off and are much more cost effective.

Best,

Erik

Why do you think bypass caps are going to be of any benefit what so ever? This is basically snake oil.

Best,
Kris
 
I have installed the caps in one of my two speakers. For the curious, the speakers use a Mundorf AMT tweeter and 6.5" Scancpeak revelator sliced paper woofer.

The high pass crossover LOOKS like a third order filter, but it's not. First cap is 4.7uF, second is 10uF.

The prime caps are Clarity MR. The Duelund is bypassing the first cap. The scond cap, at 10uF, is bypassed with a 0.1uF Audyn True Copper foil. The Audyn TC sweetens up the midrange and gives me goose bumps. Not sure if that's more realistic, but it seems I like goose bumps. Who knew?

My initial impressions after 30 minutes of barely being able to sit are mixed. Nothing bad has happened, but I don't yet hear the $200 worth of value.

The most noticable effect is a focus in the strings. You feel on a good recording that you could almost pick the brand of strings being used in the guitar. They become palpable, and high frequencies more open.

But that's it so far. In fact, if all the caps do is make strings so clear it may be a negative. My guest reviewer will be here later today or tomorrow. She has the ears of a 19 year old and can usually tell when I've changed something. Stay tuned. IN case you are wondering, I went around looking for reviews and found zilch, so I have no preconceived notions other than what's on the label.

Best,


Erik

Erik, as you learn more about science, one of the prime rules of audio upgrades you need to be aware of is the Law of Diminishing Returns. Putting a high value BP cap on a high value cap won't do much. Replace that 1st MR with a NPE, and bypass it. You might hear a difference then.
 
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eriksquires

Member
2013-05-10 4:11 pm
Speakerdoctor,

A bypass cap on the larger cap was a very good thing. Clarity just release a CMR version which I suspect will remove the need for bypassing. One of the odd things I discovered while measuring the MR versions was relatively high ESR, compared to equivalent MKP. This increased ESR seemed proportional to uF size. I theorize that within the CR line higher value caps benefit more from bypassing.

It will be interesting to revisit this in the future with the new CMR versions. :)

Best,


Erik
 
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Interesting post (I know its old) - I'm surprised there weren't more comments.
One thing I am curious about Erik - I thought the second tweeter filter cap in series (3rd order normally) was supposed to be at least 3 times the value of the first to avoid any resonance? Anyway, do you still have this configuration and did it settle down nicely in the end?