Non-magnetic latching?

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I've opened a couple models of small sealed latching relays and the latching mechanism in both had small permanent magnets for retention. Can this possibly affect sound, being quite close to the contacts? Also, does anyone know of latching relays that use spring-based retention? From what I see in datasheets, the type of mechanism isn't normally listed.
 
possible source of microphonics if conductors move relative to the magnet, or actuated coil for that matter - doesn't have to be latching relay to have a B field

some audiophiles are sure ferromagnetic component leads are audible problems

but others (likely even some of the same audiophiles) rate transformer attenuators, switched by reed relays as the "the ultimate" volume control

there are precision scientific, industrial measurement instruments - including AP audio analyzers that use relays all over

understand your parts, cirucit, design, layout to evaluate, control any issues
 
Maybe I should rephrase the first part of my question: while the comments indicate than any effect would be miniscule, can someone give an order-of-magnitude estimate of such an effect in dB relative to the signal? For example, if it's < -120 dB then it cannot possibly be audible; if it could be larger than this, then audibility is at least arguable.
Also, I'm still curious if they make spring-latched types.
 
To quote Eva:

"Mechanical contacts have been used for ages and over time they are well known to become dirty, oxidized, noisy, coated by a layer of every substance volatilized in the ambient, etc... In the end they produce great amounts of distortion when small signals are involved. For example, relays have a minimum current rating and special ones are required in order to switch small signals. After some aging, the contacts in standard relays and switches have trouble to start conducting when current/voltage is too low. This becomes worse when some DC component is involved due to electrolysis."
 
Only to those that were sealed in a vacuum.
Low-level signal relays or switches use bifurcated gold-plated (or other noble materials) contacts. You never use "toggle" or preassure type switches or contacts for low-level signals, allways use self-cleaning (like slide) switches. E
 
Only to those that were sealed in a vacuum.
Sealing in vacuum makes no sense due to the pressure difference. It's much easier to use a non-reactive gas such as argon or helium at slightly below atmospheric pressure (i.e. at max altitude the relays are likely to be used at). This decreases structural requirements of the relay body and seal. Since we're talking about low-level signals, arcing is not an issue.
 
When the relay isn't moving, the field from the magnet is constant and has zero effect. If you want to do a test, put the biggest neodymium magnet on your turntable leads and see if you hear a difference. Wait, have somebody else put it there (or pretend to) otherwise you probably will hear a difference. There's no "dB down" number involved since there are no ac signals to compare. It's a non-issue.
 
The contacts and the rest of the signal paths through the relay are inductors, just low inductance ones as they're not coils; therefore, the ferromagnetic material in their vicinity must act to an extent like the core of an inductor. That doesn't move in a normal cored inductor either, yet obviously the core has an effect! No doubt the scale of the effect is very small in a relay, but I haven't yet read an order-of-magnitude estimate of how small it is.
 
Sealing in vacuum makes no sense due to the pressure difference. It's much easier to use a non-reactive gas such as argon or helium at slightly below atmospheric pressure (i.e. at max altitude the relays are likely to be used at). This decreases structural requirements of the relay body and seal. Since we're talking about low-level signals, arcing is not an issue.

Here is an interesting pdf in part relevant to this thread.
The document focuses mainly on nitrogen and sulfur hexafluoride as fill gases, so these are probably more commonly used than argon or helium.
 
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