Filter Cap Temperature Rating?

[Enzo]

Comparing the Panasonic 105s to the Atoms is not a fair comparison. To test the claim made, one tests a Panasonic 105 against a Panasonic 85 of the same series. All of those may have better ESR specs than the Atoms, but it is not the temp range that causes that. One would also then wonder if 105 Atoms were higher Z than 85 Atoms. DO Atoms even come in both?

[Steve Conner]

Yes. Atoms are insulated from the demands of modern capacitor usage. Nobody puts them in switchmode power supplies, so they can have the same crappy, erm, "authentic" ESR that they had in 1959 or whatever.

ESR doesn't really matter in a guitar amp, in fact you can argue that it should be nice and high if you want that authentic crusty sound with lots of vintage hum. But I think modern electrolytics are better bang for the buck in every respect.

[Chuck H]

Yes. Atoms are insulated from the demands of modern capacitor usage. Nobody puts them in switchmode power supplies, so they can have the same crappy, erm, "authentic" ESR that they had in 1959 or whatever.

ESR doesn't really matter in a guitar amp, in fact you can argue that it should be nice and high if you want that authentic crusty sound with lots of vintage hum.

You can keep 'em. The extra ripple on my last build with Atoms is an unwelcome improvement. I'm not looking for vintage problems. I build new amps and I expect them to perform as such.

I don't go in for "relic"d new instruments either. If anyone tried to spray yellow lacuer with dirt in it on my chrome hardware I'd kick their ass. You'd never in a million years see a motor head scratching up his restored '68 Camero to make it look more age authentic. What the hell is wrong with guitar players?!?

If someone actually asked me to build them a "vintage" amp complete with reliability and noise problems I would peel them and fill their anal cavity with NOS mustard caps.

[guitarmike2107]

If someone actually asked me to build them a "vintage" amp complete with reliability and noise problems I would peel them and fill their anal cavity with NOS mustard caps.

Hah ha.. are you high on red bull or something, never heard anybody threaten to peel another person, sounds like you have watched "Silence of the Lambs" too many times!
Surely filling the anal cavaity with NOS Mustard caps would cause a sweeter overtone to toots..

[fyl]

I don't think you can go by published specs. I've never seen any for Atoms!?!

Just ask Vishay. They'll reluctantly supply datasheets. Here's one, for the common TVA 1908 40µ/500V.

TVA 1908 SPEC SHEET JUL 3 2007.pdf

Wow, 6.25R ESR and 0.33A max riple current...

[R.G.]

Nota Bene: It is always possible to "dirty up" good, modern, low ESR caps by inserting a small-value external resistor in series with them. This cures the objection that the caps "change the sound" by reintroducing the imperfections of the original ESR, and at the same time makes the setup more reliable by removing the power dissipation that the ESR introduced in the way of heating. The ripple current limitation is primarily a thermal limitation, caused by the I-squared-R heating of the ESR. Metaphorically moving that heating outside the capacitor by putting it into an external resistor makes the capacitor heating much smaller. The low-ESR high-temp cap will still have a longer life.

ESR is also dependent on the winding technique and connection tab technique inside the caps. Foils with multiple tabs instead of end-tabs will have much lower ESR; capacitors with connections to many tabs on each end of offset foils will have even lower ESR, and lower heating.

ESR both causes heating, which lessens the cap's lifetime, down to nearly zero in some cases, and also causes higher ripple as the I*R voltage is impressed on top of the capacitive ripple.