of capacitors and cables

Hello head-fi,

I'm a Newbie to this forum. The adventure started about six months ago, when I was walking through the Adelphi and saw a display window with headphones. There was no shop, only the address of a unit. I was excited... was this really a chance to pick out a headphone and an amplifier from a reasonable selection? It was thus I found Jaben and met Wilson.

Initially, after much deliberation, I bought a Predator and an HD650. I have a strong recollection of the head-fi Pico vs. Predator thread... quite a saga. (I also remember a long discussion on the directionality of carbon resistors, which was quite amusing.) Anyway, back to the essence: listening to the Predator, fed by an iPod 4G and driving HD650's, I was stunned. The level of emotion was unlike anything I had experienced from headphones (or speakers, for that matter). I must thank Insomniac, who sold me his SR-71. This has since become my all-time favourite amplifier. The HD650s have since acquired a Cardas cable (thanks to SR-71Panorama) and I have managed to finally secure an iMod 5G, which brings me to the present post...

I was looking at the 5G and reading about how a dock with good caps would enhance the listening experience. How could I resist? I looked at the "commercial" offerings, considered their cost, and wondered... would I do it differently? You have probably guessed. I looked through several capacitor reviews and asked for advice. The Teflon vCaps were highly recommended, but come with a slight metallic (hard) quality to their sound (I've never heard them). Two caps in parallel for each line or one? A leading expert suggests one. So, which cap tops them all? Silver Audio Note (UK), of course (still a notch below Audio Note Japan, which is beyond the reach of common mortals). A 3000 USD dock with silver foil capacitors seemed like overkill. So, the next recommendation was copper foil. Jensens look good. Reading further, I questioned their insulation: paper-in-oil. Then, looking at Audio Note's website, I notice that Peter has switched from paper-in-oil to Mylar, the same insulator he uses in his silver (very expensive) capacitors. He also offers to exchange the copper foil, paper-in-oil capacitors that develop defects. Hmmmm. I call Audio Note UK and ask as politely as I can if they would kindly, please, pretty please, ship out two 3.3 micro-farad copper foil with Mylar capacitors (52 GBP each).

Now, back to the wires, what to use? Jena is the reference. My buddy Steve uses Jena and silver. Nice. What else is available? Well, one lonely posting on head-fi mentions a Crystal Cable Piccolo interconnect. What is this? Crystal Cable, sounds good, but funny... a glass cable? Looking further, I find them on the web. I finally discover that they make wires ranging from a few hundred dollars per meter to several k USD per meter (that's thousands of US Dollars, in case it wasn't clear). I was struck by the fact that reviewers said that they work and are worth the price. What on earth??!! Maybe these Crystal Cables will be good enough for my dock...

I got in touch with Gabi, one of the more remarkable people I have ever had the pleasure of dealing with. In her gracious kindness, she actually cut the wires to the lengths I requested and shipped out a one-time order of Crystal Cable Micro.

All of this went to Steve (down under, lives near to where I hang out). He actually designed and built the dock. His patience and professionalism know no bounds (that I have discovered). The dock is sealed, since I live in a humid environment. Pictures are below. Beware of the caps, they are not only large, but heavy. If you exercise regularly, this dock will help you train for the next Olympics… it weighs in at 922 grams (two pounds).

So, here go the images (taken by Steven). Let’s start with the caps:


... and the wires:


Top right shows a mini-to-mini IC, made by Gabi. This is Crystal Cable Standard grade, a notch above the Micro wire. A closer image of this IC:


Stripped Micro wire (NOT a sexist remark):


… and a comparison with other stripped wires (this is getting bad):


Moving onto the dock, the front face:

Notice the wires have an intrinsic rigidity.

The inside of the dock:


And the capacitors inside the box, showing why it could not be any smaller:


When everything comes together…


Last, but not least, since I live in the tropics, the entry and exit points are sealed and a silica gel packet is inside the box (Steve’s idea):



Steve also made an LOD (with blackgates) and a female-mini-to-RCA IC, as shown below.




The sound is remarkable (it's a week since I received the dock). I compare it to excellent red wine: liquid, full-bodied, and very, very luscious. Sorry for the buzz-words… I can’t do the soundstage-in-my-head thing.
The dock's practicality is questionable. While being portable, it is quite big and heavy (for those who felt the SR-71 was large, this is at least twice the size).

The following is quoted from Steve, who was the first to listen to this rig (after he diligently burned-in the capacitors). “Certainly the Audio Notes are not cool or neutral though! The one word I did get hit with is smooth. I think that leads to many hours of non-fatiguing listening, which is nice. That's not a maybe/maybe not difference V the Blackgates, it's a big difference.”

What I will say, after more listening, is that the dock turns the iMod into a completely different beast, from very good to seductive, highly seductive, even after listening for a prolonged period.

Today, I enjoy HD650/SR-71 and a Predator/DT880 in the office. My partner has discovered the HD485, driven by a 5G iPod (in a green leather case).

I have chosen to share the fruit of my meanderings through head-fi and portable audio as a way of thanking this community, who have taught me a great deal and, mostly without their knowledge, guided all I describe above.

I would like to thank Uncle Wilson for introducing me to this pastime. His generosity is remarkable and I have very much enjoyed spending time with him. I would also like to thank Steve for his patience and unflagging diligence as this project took its good old time. Gabi has been exceptional and I very much hope she will make cables for us. They are beautiful and, in my opinion, very serious contenders for a new benchmark. Silver filled with gold = clarity (... Crystal).

I remain at your disposal to answer any questions.

Feel free to flame me. I love the heat.

Will I am.


P.S. A question for all ye portable audiophiles (the equipment, not the listener): is anyone working on a portable music source with USB out, preferably with low jitter?


Disclaimer: Since I am new to head-fi posting, I would like to clarify that this is not the fruit of my work on behalf of any company or entity. It was my own initiative and I paid for all materials and labour out of my own pocket. I did my own research and requested advice from a few people. They are not responsible for any mistakes I may have made, entirely on my own.

RCA connectors

Thanks.

Yes, I believe they are Silver Eichmanns.

I haven't done the entire calculation. The caps were 220 USD with shipping and the quoted retail for unterminated Crystal Cable Micro is 200 Euros/metre. The price of connectors is known. The box is about 20 USD and we need to add the labor involved. I estimate the total cost for the dock plus LOD and IC's at slightly over 1000 USD.

follow-up

I have been listening to the output of this dock through a Rudistor RP5.3, kindly loaned by Wilson. I have found few reviews of this amp, which looks like a sleeper to me. It's a hybrid amp. The sound is remarkably well-controlled and alive. The dock opens up the iPod as a source, allowing it to do justice to a decent amp. Listening with three different headphones: HD650, DT880, and PS1 (loaned by Wilson), it is clear that the Rudistor does what the SR-71 cannot do. This was most evidenced by the PS1, which sounded thin and pretty poor off the SR-71, coming to life with the Rudistor. I was also surprised by the HD650, which seemed to show more clarity with the stock cable than with the Cardas. What I will say, to conclude, is that the dock has opened up the iPod as a viable source for a decent full-size amp, allowing me to discover this new dimension (a new experience, for me).

when it rains, it pours

Two posts in one day. Wow!

Very interesting. Thank you! So, you suggest that using a 500V-rated capacitor for a 2V application is overkill? Maybe that explains why the box weighs 1kg. My selection was based on this shootout. I cannot say that I am an expert in capacitors. That would be ludicrous. My only selection criterion was how to couple the output of an iMod (i.e. its DAC) in a way that brings out the most sonic quality. The calculation for the value I chose (3.3 micro-farads) was made by our buddy Steve, who ran a basic equation for determining the corner frequency (freq = inverse of (2pi.C.R)). For a 47k-ohm input impedance, typical across most amps, including the Rudistor RP5.3, we pull up a value of 1.03 hertz. Very low, you say. Phase distortion may occur (nominally, as there is no sharp cutoff) up to a frequency of 10 times the corner frequency... 13 Hz. Ok, we are safe. However, reduce the capacitance to 1 micro-farad and this frequency rises to 34 hertz, beginning to intrude into the audible spectrum, particularly in a region where bass-heads (which I do not consider myself to be) are most sensitive. So, I ended up with Audio Note Copper foil (in Mylar) at 3.3 micro-farads... for a total weight described above.

Having said all of this, your comments interest me and I find the suggestion that smaller caps would work as well intriguing. You are suggesting that a thick dielectric could get in the way. I really, really don't know, but am prepared to consider the possibility. More to the point, I may try the Hovland capacitor you propose. Proof of the pudding... is in the eating. Translated: Proof of the capacitor is in the listening.

Not to state the obvious, I did all I could to minimise solder joints and interconnects. That is why the dock went straight onto the wire and the termination is a mini. Today, with a full-size amp in mind, I can see how two RCA plugs would be an improvement.

My, oh my... how am I going to go back to my portable rig?

What do I think? I think I very much appreciate your contribution and will look into sourcing the Hovlands for a new dock! Thanks you for providing a concrete example.

From Singapore to Colorado... I definitely look forward to reading your impressions. Since Singapore is on the way from Colorado to Adelaide, if you ever stop by, it'll be a pleasure to meet you. Without Steve, many of these experimental projects would not see the light of day.

From Liverpool FC to Wadia 170iTransport...

Thanks for the compliment. I didn't consider the Wadia out of ignorance, not knowing of its existence. Looking slightly further, I realize that I was looking for a portable source. I was fascinated at how Vinnie had taken the output of the iPod DAC and allowed the possibility of choosing the coupling caps. The iPod, in my opinion, provides an exceptional combination: large storage, portable, user interface, and a decent DAC chip (for a portable device). I understand that many people listen to CD's from a source (or even Vinyl from a turntable). I have not gone there yet and, where I stand today, I view CD's as an archive. Digital music is most conveniently stored for access on a hard drive. So, the iPod allows portable access to stored music. I then looked at the commercially-available capacitor docks, realising that higher quality caps enhanced the listening experience considerably. I then looked at this capacitor comparison. Then I asked myself... since I do not do much DIY, how could I optimize the output of this portable source (in a portable, or at least transportable) manner.

So, I learned something today. I had no idea one could extract the digital signal from an iPod. I thought the only output available was from the internal DAC. The Wadia 170 will allow even the newer iPods to be used. Then, the only remaining challenge is to find a good DAC, with a solid output stage. Some comments I have seen suggest that DACs from the '90s have far better output stage than those of today. Indeed, for home use, this would seem the better route. In fact, maybe a Squeezebox into a DAC... bypass the iPod.

Thanks for the tip.