Product: ClarityCap (ICW) SA Capacitors
Manufacturer: ClarityCap - UK
Cost (approximately): 1 uF: £2.40, 6.8 uF: £6.20, 10 uF: £8
Reviewer: Maarten van Casteren - TNT UK
Reviewed: November, 2006

Introduction

One of the websites I like to check from time to time is Tony Gee's Humble Homemade Hifi. It is a very interesting site about DIY speaker design and building. One of my favourite pages is Tony's capacitor test. Here he lists over 20 different types of film capacitors, with his personal experiences and opinion of them. As usual the most expensive are the best, but luckily there are a few exceptions. One of these are the ClarityCap capacitors, which he found to be of very good quality and very neutral sounding for a reasonable price. Reason enough for me to investigate. I contacted ClarityCap and was send some samples to experiment with.

All caps I used were from the SA range, which is one down from their top range. There's an even better DTAC range, but these are complicated to use as they are very big and awkward sized and don't have leads, but screw terminals. The SA caps are already rather large, I have to say. For many applications that will be a problem, but I managed to squeeze them in. ClarityCap have three other ranges APW, PW and PX. These are more affordable and also smaller that the SA range, but obviously of a lower quality as well. ClarityCap is also known as ICW, by the way. Actually, ClarityCap is a division of ICW, with ICW focussing on industrial applications.

In use

The first place where I tried them was as DC blocking capacitors in my Anatek A50 integrated amplifier. These caps are located between the volume control and the actual amplifier and serve to keep DC out of the amp. I didn't know what cap was used in there, as it was installed label down. But when I took it out it turned out to be an ICW PW capacitor! That means I was just replacing it with the same brand, only 2 series up the range. I used a 1uF SA capacitor, which just fitted the space left by the 3.3uF PW cap. The difference in value shouldn't be a problem.

I do like the sound of my Anatek A50 amp very much, but lately I have also been using my old Electrocompaniet ECI-2 again. This is a 50 watt integrated amp as well. Compared to the Anatek it is a bit warmer and smoother and projects a soundstage that is perhaps a little deeper. The Anatek has slightly better focus, though, and tighter bass. Actually, there is very little between these two amps: it is more a question of character than quality. It has to be said that the Electrocompaniet has been modified with schottky diodes and Elna Silmic as well as Black Gate capacitors in the power supply, and the Anatek has had its volume control replace with a rather nice Dact CT2 stepped attenuator.

When I changed the input capacitors on the Anatek it became warmer and sweeter, resembling the Electrocompaniet more than before. The mids and highs were a bit cleaner in tone. There was certainly no loss of detail, just less of an 'edge' to the treble than before. After some use the warmer character changed to a more neutral tonal balance and improved transparency. Compared to before, the sound was still a bit richer, probably because the cheaper cap added a little bit of sharpness to the treble. Small details are now easier to hear because the whole sound is more relaxed. For the money (about £5) this has to be the best modification I've ever done. A clear improvement in sound for the price of a cheap CD!

After this success I tried them in my speakers too. My Dynaudio Contour 1.8 mk2 speakers have a first order cross-over, which means that the high-pass filter section for the tweeter consists of just a single capacitor, in this case 6.8 uF. This is an excellent candidate for upgrading. Installed was a Solen MKP capacitor, which are considered to be good, but not in the same class as the ClarityCap SA's. The only problem with my Dynaudio speakers is that they also contain a special all-pass section in the cross-over that delays the signal from the tweeter so that it will be in phase with the woofers. This section contains another 2 capacitors, each 10 uF. The signal for the tweeter passes through all three of these capacitors, in series! That means that just replacing the single 6.8 uF didn't make much sense and I had to replace all three of them. It was a bit of a squeeze, as the ClarityCaps are several times the size of the Solens, but I managed it in the end.

Strangely enough I didn't notice an immediate improvement, like with the amplifier. The overall tonal balance of my speakers was the same as before. I did notice a slightly more spacious soundstage and sweeter highs, but I have to admit that the difference wasn't enormous. But then, during the next weeks, I found myself listening to music even more than usual. And, it seemed as if my speakers were getting more and more detailed too. There was certainly a crispness to the treble that wasn't there before and, again, it didn't come at the expense of musicality at all. If anything, the sound of my speakers is now easier on the ear than before, while at the same time having higher resolution and clarity. Focus was improved too, with images between the speakers being a bit more solid and stable, and better 'corner-fill' behind the speakers. Soundstage is slightly larger in all dimensions. Strangely enough the bass is now a bit stronger and the midrange is clearly a bit fuller, while overall tonal balance is as neutral as before (read: as neutral as my room). In addition to this, the sound is now less attached to the speakers, with only really nasty sibilant noises having the tendency to come from the tweeters, but everything else originating from somewhere in the soundstage.

Conclusion

The name ClarityCap is certainly an excellent choice for these capacitors! Clarity and transparency are probably their biggest virtues. Perhaps there are better capacitors around. There's always a better product. The difference cannot be very big, though. And these must certainly be one of the best value capacitors available. Expect to pay several times more for anything better than, or even equal to this. At these prices you really cannot afford not to try them in your system. Both use as filter capacitor in loudspeaker crossovers, or as DC blocking caps in amps and CD players is highly recommended.