In one of his books, KOC makes mention of "cheap offshore caps" and specifically mentions that IC should be avoided. On this he is in agreement with AW. He is generally a frugal type of builder--this part worries me because he feels it important to pay extra for premium. Jim
Hi Jim,
The gist of KOC writings and personal communication is as follows:
KOC dealt with repeated issues of failures with Illinois caps and in his experience IC caps are unreliable. The IC caps has been mentioned in his books. His opinion was a cheap cap that failed, you get what you pay for. "Illinois Caps still make the worst electrolytics on the planet. Their claim to fame was low cost back in the early '80s - their plastics are fine; don't waste your money on their electrolytics!" & "The IC electrolytics are just poorly designed as far as I can tell. Tophat used them and anyone who replaced the caps with any other brand found the amps had better low end response and a less gritty sound.
Illinois Capacitors hit a price point that makes them very appealing - at least it did so ten years ago. The 500V rating on their axial-lead units is also appealing with the prevalence of 470-500V operation of most modern circuits. I was never a fan of axial-lead caps, so had no problem subbing radial-lead units where axials used to be, but many techs are afraid to make such changes.
Modern manufacturing allows less expensive caps than IC's to outperform them very easily. Electrolytic caps are very compromised by design, that is, they deviate from ideal capacitor function in many ways, but Illinois manages to have about the most deviant examples possible."
The owner of Island Amps (another professional Canadian Guitar Amp manufacturer) also saw more than his fair of Fender amps and Peavey with bad IC caps in repair work. "I completely agree with Kevin when it comes to the Illinois caps! I've seen a lot of Peaveys and newer Fenders... so I see a lot of bad Illinois caps." Dante likewise, saw issues with F&T caps. His recommendation, once you go radial, you never go back.
Dante Carrers' comment seems to indicate that IC failures weren't restricted to one model by one manufacturer.
On the repairs that I have done on Fender amps (the non-vintage ones) the components sourced came from the cheapest suppliers, as far as I could determine mostly from China, Thaliand, Indonesia, etc. I couldn't find anything that could be verified as being made in the US, other than the Speakers. Also, the PCB traces were thinner than should have be for long term reliable operation. It was as though every possible cost reduction that could be incorporated into a design was there. I haven't had to replace an IC in a Fender amp, but I've seen and replaced my share of resistors and zeners that should have used a higher wattage for added reliability rather than save a fraction of a penny. It was though overbuilt or overspec'd and Fender are mutually exclusive concepts. Consumer grade quality sold as professional grade product.
KOC does not recommend Atoms caps, any expensive components, or Voodoo parts. His only positive comment on Atoms were their larger physical size reduced parasitic capacitance in some amps, but larger spacing (with smaller sized parts) achieve the same goal for less money.
KOC uses Solen PP film Fast Caps in place of Electrolytic Caps for a clearer sound, reliability, and longer life expectancy than Electrolytic Caps (the life expectancy of the amp). Solens do not have the "electrolytic distortion" that E-caps have (but one can recapture this tonal quality by various methods). To offer a lower price amp model, KOC has introduced an amp with Electrolytic caps.
In his "Super Stock" or updated versions of classic amps or in projects of his design in the TUT series, KOC recommends radial caps for better physical reliability over axial E-caps. And yes, the Axial Caps by any of the "cons" and other brands without "con" in their brand name have been lower priced (Japan's recent disaster may or may not change these prices) and are generally of high quality. This market has been driven by computers, mostly the monitor market. "Mitsushita through their Panasonic brand make very excellent caps at low cost, sold also as Nichicon. These function and sound better than caps costing many times what these do, and occupying much more space than these. Sprague and Mallory are not better than Nichicon but cost a lot more and have the "favoured voodoo" approval."
I have used Atoms (I test all my caps with a Heathkit or Sprague Capacitor tester at full voltage before hand) and Nichicon for that matter, and hadn't had issues others have mention, just as many have used IC without a hitch, especially the history of IC with Hoffman Amps. Your mileage may vary.
Best Regards,
Steve
