This question is aimed to TRUE Elec Engineers, not fuse or wire directionality believers.



Has any of you ACTUALLY worked with and recommend a SSR which does not introduce any audible distortion on the speaker line and which can operate with a large range of trigger voltages (12 - 48 VDC, may need to have on board voltage regulator for this range).  I am building a speaker DC protector and do not want to use electro mechanical relays becoz of DC arcing and contact erosion issues.  It needs to be capable of switching up to 15 amps at about 100 volts.

Only TRUE engineers reply please.

Thanks

128x128cakyol
@ssg308, since some SSRs internally use back to back SCRs or triacs, they may NOT turn off when the trigger is removed and DC is flowing, which would destroy the speaker in a second under fault conditions.

Thanks
Hi Cakyol

Darn, a legitimate question on this forum.  Ok, I'm a real EE.  I'm not aware of a high failure rate in amplifiers, but perhaps just that...unaware.  Are you concerned with a specific aspect of your system that you want to protect your speakers with something faster than a fast acting fuse?  I admit to not having used an SSR in your application, but like you, would be curious about any acoustic artifacts associated with putting even a low impedance semiconductor in series with the speaker wiring.  On the other hand, as infrequently as a mechanical relay would be switched hot, i.e., under heavy load, I wouldn't have any concerns about contact erosion or wear for one with contacts that are properly sized.  Also, I'm curious what you were going to use as a derived control signal for the relay of your choice.

Keep us posted on your progress and results!

Hi Cakyol

It might save some time and effort by going to (as suggested above) some engineering or diy audio sites to ask this question. Reason I say this is because finding someone here who is experienced at swapping out different solid state relays is more than likely to be over the engineering pay grade here.

Not saying there aren't some smart people here, just saying maybe not as specialized as what your hunting for.

good luck

Michael Green

Just on the surface analysis, an SSR would sound like crap, overall, in any audio application.

This is so obvious to me, that I’ve never made it past the idea of looking at the acronym of SSR, and then moved along and away from such an idea.

Ie, that the thought was discarded as thoroughly as possible, before it even began.

Like the idea of taking the tuna sandwich I might be holding and smearing it on my face, as a way of ingesting it. Silly beyond belief, not to be considered a thought whatsoever.

And that’s what I think of the idea of SSR’s in audio gear. That the thought was discarded long ago, by just about anyone in the world of audio that you can imagine.

A gentle but quick mental/internal ’no, that’s not going to work’, and then they moved on. Relay or circuit breakers is better, as the quality in sound, is better. Better than any SSR.

And all those audio designers and engineers you might want to get an opinion from, they invariably understand audio quality and that definitely includes the power cords, the fuses, and the cables -- all as being important. This is about audio quality, not some numbers squeezed out on the face of a meter and analyzed via spec sheet.

1000 kilos of raw dung will, displacement wise... fit inside my car, and the volumetric spec is there for it, but I’m not about to test that or do it.

My response is mildly over the top but honest in my analysis of SSR’s and my opinion on them in quality audio... I’m just reflecting the seeming mood of the OP itself....