I really don't know about steel but I kinda wish they would use more copper. The arguement is that copper oxidizes and then makes for an ugly and nonconductive surface. My personal experience with stripped copper wire is that this process is barely noticable if it occurs at all. The commonly seen brass posts are in fact an alloy of zinc and copper but I understand it is not a great conductor.
13 responses Add your response
I hear ya'. The reason I ask is Legacy uses SS for their binding posts on the Whisper XD's and stainless is rated VERY low in conductivity vs. copper and gold plated copper. Seems a very odd choice! This is a GREAT sounding speaker and I wonder how much better it COULD sound if a more 'industry standard' material were used?
I would guess that it doesn't make much difference. Resistance of binding post is most like in order of milliohms* while speaker is in ohms. For the Damping Factor, speaker impedance is mostly resistive and in addition there are inductors in series. Woofer inductor is most likely 0.1ohm. There might be other factors that affect the sound but not conductivity IMHO.
* - Binding post is in order of 0.4"dia corresponding to AWG000 wire. Copper wire AWG000 resistance is 0.2mohm per meter. Stainless Steel is 50x worse than copper but your post is also not longer than 2cm (1/50x1m). Result is under 1mohm.
I agree with Kijanki. A resistance of 0.0002 ohms or thereabouts is negligible compared to the other resistances in the path, including the speaker cables.
I would imagine that IF the use of stainless steel has any consequences at all, they would relate to the interface between the stainless steel and the gold or copper or whatever other material it is being mated with. Contact integrity, changes in smoothness after repeated connection/disconnection cycles (e.g. "galling"), corrosion due to galvanic effects, low level rectification effects, etc. I have no particular knowledge regarding those kinds of possibilities (and for all I know stainless steel might even be advantageous with respect to some interface effects, depending on its specific formulation and what it is mated with), but I can't see the intrinsic conductivity of the material as being of any significance.
One potential problem with Stainless is the galling effects of the nut on the speaker post- over time they may tend to lock up on the threads if the post and the nut are the same material.
Stainless cannot be soldered so it may well be that the actual resistance of the connection (since it is mechanical) is much higher than otherwise forecast.
Before SS was developed, tin was a favored non-corroding material. It would be a better conductor than SS and its harder than copper, so it would hold up. I am wondering why such a product has not appeared, but the SS one has...
Well there are certainly dissimilar metals involved here in that the posts are SS, the rear anchor nut is galvanized steel and the spade connectors on my cables are Rhodium plate over copper. And these posts are quite substantial, they are .710" at their widest with a 2.5" ( actually the metric equivalent) overall length and a 5/16" threaded shaft. Big chunks of metal! They are beautiful, but would not have been my choice for a high end speaker.