Hey John
much thanks for all the info !!!
I often find the saying " less is more "
here and around the various forums dedicated to sound and analogue audio technologies ,
there is absolutely no intention of questioning regarding the fact that
each designer does what he thinks is best ,
but it is also true that a top quality potentiometer
can do the same thing as the long row of relays....
and for a gain control also a rotary switch with lot of positions and related resistors
can do the same job..
(...although perhaps with about the same number of pins to be soldered..)
except that by adding a control logic to the relays row
various volume level positions can also be stored and quickly recalled "on fly"....
perhaps the only real advantage compared to a simple potentiometer
or a rotary switch....?
cheers
You may be overthinking this.
Is it worth it ? - Well what's the alternative if you require the functionality ?
I suppose it's direct point to point connection with lots of manual patching.
Same idea as avoiding patchbay connections - and I have seen a mastering engineer eschew that wrt digital audio connections - evoking much eye rolling from the studio's technical bod.
So - relays - the thing is you have to select the correct type for the application.
As JR as indicated - in high power / current situations you can get issues. If you get it wrong contacts may 'weld' together.
At the opposite small signal end contacts that have no or very small currents may fail due to pollution (oxidisation/tarnishing) of the contacts. You need to select the correct contact type.
And think about where they are in the signal path.
In a previous position (not audio but the same principle applies) I noticed a steady stream of service returns of units that had been manufactured and sold before I had been there. They were all around five years old. Talking with the service tech and looking at the schematics it became clear that the issue was that there was negligible current - basically just OpAmp input bias current - going through the relays.
imo relay remain the premium switching solution. Well preferred over normal switches.
Generally in a mastering scenario I'd suggest that the increase in productivity afforded by a good switching solution outweighs the possible cost of relay failure.