Hey everyone,
I'm trying to come up with a plan to incorporate into my IronPre SE and M2x. On my vintage amps there's always a multiple speaker selector switch - I'd like to have 2 outputs for the IronPre and 2 speaker outputs on the Amplifier as well. The easy button seems to be just use a high quality DPDT switch with gold contacts. Is there a better way from an acoustic / design standpoint? Was looking at the IronPre and considering trying to make a daughter card with relay controls but that may be over thinking and over engineering the problem.
Another idea was a simple external switch box. I don't want a huge rats nest of RCAs so the internal one sounds more appealing to me but if its all the same for acoustics this may be the switch box would be easier.
I'm trying to come up with a plan to incorporate into my IronPre SE and M2x. On my vintage amps there's always a multiple speaker selector switch - I'd like to have 2 outputs for the IronPre and 2 speaker outputs on the Amplifier as well. The easy button seems to be just use a high quality DPDT switch with gold contacts. Is there a better way from an acoustic / design standpoint? Was looking at the IronPre and considering trying to make a daughter card with relay controls but that may be over thinking and over engineering the problem.
Another idea was a simple external switch box. I don't want a huge rats nest of RCAs so the internal one sounds more appealing to me but if its all the same for acoustics this may be the switch box would be easier.
For the preamp a gold plated switch is good - gold plating handles a few mA reliably.
For speaker switching its a high current application, I wouldn't use gold. Gold is for low current low-power signals (think 1mA or thereabouts) gold is far too soft for heavy duty and just gets scraped off the contact surfaces or even melted on first few uses. Unless you are willing to pay for extremely thick gold plate that is. Power contacts use much higher contact pressure than signal switches, and gold is soft as butter (almost)
However the M2x is pretty low current as amps go, so you might be ok with gold-on-silver contacts.
Nickel silver and a few other silver-based combinations are generally used for power contacts, and copper sometimes. I would recommend getting a quad pole switch and doubling up each circuit in parallel for better long term reliablity. Be conservative in the current rating to be sure of low contact resistance.
There's also the issue of whether the switch uses ferro-magnetic materials in the contacts - this can cause distortion on a speaker signal due to non-linear inductive reactances - more important for low impedance speakers and higher power amplifiers.
For speaker switching its a high current application, I wouldn't use gold. Gold is for low current low-power signals (think 1mA or thereabouts) gold is far too soft for heavy duty and just gets scraped off the contact surfaces or even melted on first few uses. Unless you are willing to pay for extremely thick gold plate that is. Power contacts use much higher contact pressure than signal switches, and gold is soft as butter (almost)
However the M2x is pretty low current as amps go, so you might be ok with gold-on-silver contacts.
Nickel silver and a few other silver-based combinations are generally used for power contacts, and copper sometimes. I would recommend getting a quad pole switch and doubling up each circuit in parallel for better long term reliablity. Be conservative in the current rating to be sure of low contact resistance.
There's also the issue of whether the switch uses ferro-magnetic materials in the contacts - this can cause distortion on a speaker signal due to non-linear inductive reactances - more important for low impedance speakers and higher power amplifiers.