Are contact treatments worth the money?

Gorilla Glue works well on Banana plugs. Duck Tape works well on wing nuts but there is nothing like silicone for tweeters ;-)

Aball,
No, science has not answered all the universe's question. You are correct. However, this is an engineering problem, not a philosophical one. Believe it or not, things to do with electricity or electronics fall into the realm of electrical engineering.

I cannot explain why some 12ax7's sound better to me than others do. Most EE's that I know would not care to delve into that question and would probably shirk it off as being trivial or hokum. On the question of contact treatment, I would tend to believe that if the contacts are corroded or oxidized somewhat, then cleaning would help. This brings to my mind the question of whether the impedance effects of oxidation are linear or non-linear through the frequency spectrum. If it is linear, no worries -- turn the volume up. If it is non-linear, clean the contacts, then turn the volume up some more.

I would really like to see scientific evidence (i.e. impedance data) that contact treatments actually improve conductance between two clean conductive metals.

Another "for instance" of audiophilogy beliefs is skin-effect of audio cables. An EE prof of mine while I worked in audio shops during school worked out the calculations for skin effect for audio frequencies and a decade above for "monstrous" cables, and for coax wires. Guess what? None. No skin effect at these frequencies.

I think there is quite a bit of marketing driving our audiophile beliefs. Marketing guys sell product...

I've never seen a paper from, or attended a course in the fields of Science or Electrical Engineering that addressed the issues of the very complex waveforms, timing, timbre, harmonic and ambience cues that comprise a musical signal being transmitted through metals, and/or connections. Nor do either of those supposed authorities really have a handle on what might be taking place on the quantum level, vis-a-vis electron flow. Testing is invariably done with relatively simple signals, generated by equipment that I'd never listen to on my system. Testing done, and empirical data collected by, listening to actual music is scoffed at. That doesn't surprise me in the least as there are multitudes in this world that are unable to hear, recognize or(perhaps) admit the differences/improvements that result from our innovations and tweaks. Look at the following that Julian Hirsch had during his tenure at Stereo Review(what a joke!). Unless the surfaces of two connectors are custom machined or ground to obtain perfect/100% contact with one another: Signal transfer will never be as good as it could be. I've not seen any audio component manufacturers take that kind of trouble when designing their ware. It doesn't take a rocket scientist to understand that an application, filling whatever voids exist between two contacts with the best conductor know to science(ie: SST's silver flakes), will enhance signal(or in the case of our power sources: 120V/60Hz electrical) transfer. PS: Placebo Babble be damned!!

I use the AV Extreme and have found it to work as advertised. I only use it on my RCA's between my pre and amps and it really brings the music to another level. I would not put it on my RCA pins again as it caused problems in my amps that manifested in a series of blown fuses and tubes. I'm also leery about using it on tube pins. I just put it on the outside of the female RCA connector.

The big drawback with this stuff is you have to wait three weeks for it to cook. I have heard the Walker paste works right away so I may give that a try.

I agree with Rodman's observation. It's really more about keeping the signal flow constant than it is about super conductivity. The paste does that by filling in the micro gaps to reduce signal transfer vibration.

Hard to beat Markphd's original response. Nothing wrong with also doing a little wiping with fine emery & cleaning if desired. Away from the audiophile world you are not likely to find high cost fairy goop in critical signal paths (I think the reason for this is that testing and calibration instruments are greatly lacking in imagination). You will find some relatively low dollar goop used to help prevent a hot joint where fairly high currents are involved.