Review: KCI Silkworm Plus Interconnect

Category: Cables

This review is of the "Silkworm+", the latest offering from Kool Cables, Incorporated.

Rather than rewriting my bias and methodology for cable evaluation I will cut and paste from my previous cable review:

"Review philosophy/methodology
For me, I rank cables on one objective criterion before making judgment calls based on [subjective] factors. First, if I'm forking out cash for an aftermarket cable, I expect it to be free of colorations. Piano seems to be the best test for me. It's astonishing to me how many high end cables can't get the tone, much less the attack and decay of a piano note, correct. Brass instruments also seem to be a stumbling block for certain types of cords.

After listening for coloration, I sit down and listen critically to see if I can determine what the cable is doing. If I can easily tell, I have to figure out if I like what it's doing. Generally, though, if I hear some sonic signature I'm going to rank the cable lower than I would a more transparent cable, since my philosophy is ideally I don't want to hear a cable. I want to hear music, and let my equipment determine the sonic attributes I hear.

At some point I just let go, and listen more passively. I ask myself,"Am I enjoying the music?" If that "toe tapping" quality is lacking in the cable, I'll notice it pretty quickly in this phase. This can be the kiss of death to me, because for me this hobby is about emotionally connecting to the music and being able to step out of reality for a bit and step in to a world of memories, imagination, or both. The better the reproduction of the music, the easier it is for me to just drift off in to La La Land.

Musical preferences
Pop/rock from the 60s forward, with emphasis on the 80s; Country over the last 20 years; jazz; some Classical (mostly stuff I played while in band in high school and college); Contemporary Christian and praise and worship dating from the early 80s.

Personal preferences in cables
I enjoy a warm cables as much as the next guy. Unfortunately, warm cables IME deprive rock and country from the excitement of the percussion, and particularly cymbals/high hat. Order of importance for sonic attributes after coloration is: speed, soundstaging, detail, tonal balance, dynamic range. I like a lot of detail, but not to the point of coldness."

Historical note: Before the Silkworm+ I owned the original Silkworms. I understand the strengths and weaknesses - and the degree of same - of that cable very well. Prior to evaluating the Silkworm+ I found that the Gabriel Gold Rapture provided a bit more "coherence" somehow over the Silkworm, and there would be times I preferred one over the other based on mood. A quick description of the original Silkworms may be helpful. In my system, they were very lively and exciting without the brightness or harshness that usually accompanies "lively" cables. They did lack a little "oomph" in the bottom end, resulting in the awareness that the bass was there but without really feeling it. It is a very fast cable; I've heard others that equalled it in this area, but none that surpassed it. It gave up a bit in the "body" and palpable image area, and as I will note below, I am coming to believe that there are electrical properties that require a tradeoff between speed (PRaT) and body. Speaker designers have been frustrated by necessary tradeoffs due to electrical principles for years; it appears cables have evolved to that level now as well.

If you detect a certain degree of conflict in the narrative, it is because I really liked the original Silkworms, and allowed myself to create "perfect cable" expectations with this cable. Such a thing does not exist, of course. So although I have no affiliation with KCI other than a satisfied customer, there is a chance this review will sound overly critical in places, much like a coach who criticizes his son for not being perfect even though the son is outperforming his teammates.

Because of this, I feel compelled to set the "lenses" through which the review must be read. If you want the short version of the review here it is:

overall these are the best cables I've ever heard.

They are not perfect. Although one or more of the "issues" I note with the cable may actually be something many reading this review *prefer*, is does have small degrees of weakness in a couple of areas. But at the end of the day, they are the best I've heard in my system and in other systems I know very well.


Coloration: I hear no colorations with these cables. Beyond lack of coloration, I note very good "bite" on brass instruments when the players tongue in such a way. As a trumpet player in high school and college, I listen closely for the brilliance inherent in a trumpet's sound, and it's there with these. This is no small feat because most cables that do this well tend toward brightness. The original Silkworms also did this well, and while not bright, was a little light in the bottom end.

Sonic signature: It has one. It's incredibly subtle, but it's there. It tames bad recordings ever so slightly in the same way Gabriel Gold Rapture cables do, but to lesser degree. (GG owners will note the Raptures don't tame recordings to a great degree, either.) That is the only way I detected a sonic signature. Once I detected it I started looking for it, playing recordings that would expose the degree of the signature, and I found the degree to be very slight, as noted above. This signature is one that I think most audiophiles will prefer a cable to have. I like it, even if the purist in me condemns all sonic signatures.

Speed (PRaT): It's a half-step behind the original Silkworms. Given the Silkworms were the best cable in this area I'd ever heard, it's hard to complain as the "Plus" still exceed most other cables I've heard. I'm getting used to that half-step difference easily though because the "toe tapping" effect still exists in spades.

Soundstaging: Big jump up from the original Silkworms, and the best I've heard in this area both in terms of width and height. I had three wonderful moments with these cables in the area of width. They occurred in the recordings "Heart Full of Soul" (Rush); "All the Gold in California" (Gatlin Brothers); and "Children of Sanchez (Overture)" (Chuck Mangione). In each of these recordings there is an opportunity for specific instruments to appear right up against the side walls if the equipment is capable. The cable put the instruments right on the side wall, as they are supposed to be. Also, vocalists consistently appear above the height of the tweeters. Other instruments do as well, deepending on the recording. As for depth, they can throw images in front of the speakers, well behind them, and anywhere in between.

Detail: These are very detailed without any etching. This is due to the fantastic black background they provide. Attack and decay of notes are clear and accurate. The cables let 99% of "secondary information" such as echo of a singer's voice off a studio wall through. The 1% loss is the same trait that makes older or inferior recordings sound better than they really are. I can't say I ever noticed the 1% loss outside of the recordings I selected to specifically listen for this.

Tonal balance: Balanced, although this cable's incredibly good/real midrange leads me to wonder if it isn't just a tad warm. "Warm" connotes rolled off treble, though, and the treble, while smooth, is not rolled off. The midrange seems to be the anchor of the cable, showing off solid, palpable images that are absolutely lifelike. The original Silkworm's weakness in the bass area is not an issue with the Plus. The bass is tight and punchy, and also lends to the superior body and "realness" of this cable.

Dynamic range: Dynamic range is very good, but not the best I've heard. This may be a byproduct of the cables not fully being broken in (I've talked with someone who indicated their cables are still changing slightly after 500 hours, which is just slightly more than the 450 hours I have on mine.

Toe-tapping, non-critical listening music enjoyment: outstanding. In fact, as I've spent most of the afternoon typing this and editing I've been listening to music, and it has been a lot of fun. These cables are the only I've ever heard that give a more true-to-life presentation than the Gabriel Gold Rapture. That's one heck of an achievement, because I've never heard anything that came very close to the Raptures in that area. The Valhalla are great, but not all that close to the Raptures in the "realness" area.


One thing I did not capture in the detailed analysis is this cable's superior ability to present vocal harmonies. It is unrivaled in this area. How the cable can simultaneous place the singers in different places on the stage and blend them perfectly I don't know. It's a little eerie, frankly. It's like listening to a barber shop quartet in person at a close distance. Except this cable gives you that ability with every recording featuring vocal harmonies. I put on more vocal harmony recordings than usual because I was truly stunned at how well the Plus cables portrayed them.

There is an anomaly in construction that needs to be mentioned. ANYONE PURCHASING THIS CABLE NEEDS TO READ THIS: the Xhadow female XLR connectors are ridiculously tight, and are clearly not intended to be seated all the way to the lip of the connector! I initially tried to muscle the female connectors on to my Ayon's XLR jacks, and upon removal they pulled out one of the pins slightly. No damage to the Ayon - the pin pushed right back in to place - but purchasers of cables with Xhadow XLR jacks need to know about this.

While these cables are not absolutely perfect, they are the best, more realistic cables I've ever heard, so they're staying, and I would be surprised if anything in the next several years replaces them.

That leads me to one final point the reader may have already discerned. It seems many manufacturers are now releasing "make II" or "version 2" or similar names for their older designs, making small changes and then marketing the units as "upgrades", which they may be. But it seems to me taking on a namesake connotes modest change. This was a marketing mistake on KCI's part. The "Silkworm Plus" is not in the same league as the original "Silkworm". It is several notches higher. In fact, the gap is even wider than between the top of the line and 2d best product lines of most companies. Externally the "Silkworm Plus" looks like the "Silkworm", but whatever John Prator has done with the actual wire has transformed the Silkworm from "exceptional" to "truly lifelike".

Congratulations to John Prator of KCI. While I have good things to say about many products, I keep in my system only what's best to my ears. As I've mentioned before, these cables are the King of the Hill as far as I'm concerned, and objectively speaking are a "must hear" for music lovers with high-end, exceptionally capable systems.

Associated gear
Ayon CD-2
SMC Audio VRE-1
McCormack DNA-125 Platinum Plus
Nice review, Howard. I recently had the good fortune to have a pair of the new Silkworm+ in my system on loan from another owner. Although they were in my system for a relatively short time, connected from preamp to amp, I was able to get a good dose of their sonic merits. I'm in agreement with everything you said in your review. I also was a cornet/trumpet player in high school and beyond some, and this interconnect does indeed portray the natural bite and brassy brilliance of a trumpet like real life. The portrayal of voices and acoustic instruments is also remarkable with these cables. Just yesterday, I reluctantly returned these Silkworm + to their rightful owner and it was a sad day for me. I am saving my pennies for a pair for myself as soon as possible. Enjoy your new cables.
I agree, very nice review!
Thank you taking the time and care for a cogent review. I have the original Silkworms (which I think are great) so I was very interested in the changes you perceived from old to new. The only thing I would add is that the Silkworm designer and seller, John is one of the finest people to deal with as well. He was informative, prompt, modest, very committed to music and to my satisfaction with his product. He was objective and complimentary about other cable designs - a true gentleman to deal with at a great price.
John really went all-out on this design and it'll definately show its stuff as time marches on and more people hear them.

My two pair of Silkworm+'s will arrive Tuesday and I'll post impressions after break and settle in time takes its place.

Go Johnny go !!
The review of the Silkworm+ interconnects really interests me. What other interconnects are you using (audiophiles in general) or have used that the Silkworm+ interconnects betters. I ask for a reference, so that I might determine if I want to pursue a purchase.

Wow, now that is a review! I greatly appreciate you taking the time to write such a comprehensive review on the new cables-thank you sir! I am thrilled to hear that you are enjoying them so much and they have met or exceeded your expectations. Please keep us posted on any new thoughts, your feedback on them is extremely valuable to us here at KCI and I'm sure it's also extremely valuable to our fellow Audiogon members, thank you!

I would also like to thank the other members posting in this thread for the kind comments, thank you, very much appreciated!


it is great people take the time to post their thoughts on components & such.

It would be nicer if some comparitive references were made apart from particular contenders... eg., Valhalla & Gabriel, as the indication 'many other cables' was indeed made. Mentioning price too might be a good idea too by instilling more or less, economic impact which constitutes value, by such a notation.

At this point I can neither assume the Plus cables as equals or betters, without the pricing info. If somehow I missed that pricing mention I'm sorry but I looked thru it all twice and didn't see it.

Thanks for bringing these wires to my radar in any event.
Has anything been done to alleviate the XShadow XLR tightness problem or is this something that one must always expect from these terminations?
The original silkwork is a fantastic cable I can only imagine how much better the plus is !

In time I will upgrade to the +++

Great job John !
Pricing can easily be found on the website.

We did figure out that the Xhadow plugs work fine but you need to be careful when plugging them in and not force them to far in as they do not need to "click" into place like some other plugs do.

Thank you for the props! When you're ready to upgrade you just let me know. I hope you're doing well and staying warm!

Curious, have you experimented with other XLR terminations? How are the Furutechs for instance?
Well I am incredibly late on this but I feel compelled to reply. We brought this to the attention of Vampire right after this review was posted and they did look into what may have caused this. I cannot say for a fact that the problem has been rectified but I can say that we have not had a similar complaint since Aggielaw had the problem with his plug. I hope this helps but I would imagine I'm a "little" too late...