HaveMeterWillTravel
Senior Member
Where does EMI/EMC, leakage current, common mode noise and other considerations belong on the "audibly the same" discussion?
I get the general sense that many (most?) here do not consider EMI/EMC effects and other more nuanced design performance may never fall within the discussion of audibility, and should be cast out to seemingly oblivion. I am of the opinion that it does a disservice. Take for the example two otherwise equal USB DACs but where one may require the use of a USB isolator to prevent audible "hum" and the other does not. To an individual it clearly has an audible difference in his system! How does telling that indiviudal there is no audible difference a furtherance to a scientic method?
The standard caveat to disregard the effects by adding "properly engineered" has been rendered to the status of a near tautology. In large part because it is applied post hoc. A "yes yes, but .." type response. Yet one could that any device with single-ended chassis/ground referenced signal interconnects are not "properly engineered" since there are superior designs out there.
Unlike frequency response, gain setting, SINAD and other areas of known audible difference, the audio sphere rarely discusses where and when audible effects occur. Nor is it measured prior to proclaiming there are no audible differences between two devices.
It's niave to think audio equipment will be designed and tested to a level as to have no possibility of audible effects, yet it's not pactical to test them. Even if a product is susceptable, whether or not it ever manifests itself is higly specific to the individual circumstances. Some of us older folk may remember when certain TV's would have 'noise' when certain hairdryers were used. If you had the TV yet no one used those hairdryers in your household, you never saw it.
Does it have a legitiment scientific place in discussions of (possible) audible differences?
Or does it contaminate the "Gospel"?
This is a quandry.
HMWT
I get the general sense that many (most?) here do not consider EMI/EMC effects and other more nuanced design performance may never fall within the discussion of audibility, and should be cast out to seemingly oblivion. I am of the opinion that it does a disservice. Take for the example two otherwise equal USB DACs but where one may require the use of a USB isolator to prevent audible "hum" and the other does not. To an individual it clearly has an audible difference in his system! How does telling that indiviudal there is no audible difference a furtherance to a scientic method?
The standard caveat to disregard the effects by adding "properly engineered" has been rendered to the status of a near tautology. In large part because it is applied post hoc. A "yes yes, but .." type response. Yet one could that any device with single-ended chassis/ground referenced signal interconnects are not "properly engineered" since there are superior designs out there.
Unlike frequency response, gain setting, SINAD and other areas of known audible difference, the audio sphere rarely discusses where and when audible effects occur. Nor is it measured prior to proclaiming there are no audible differences between two devices.
It's niave to think audio equipment will be designed and tested to a level as to have no possibility of audible effects, yet it's not pactical to test them. Even if a product is susceptable, whether or not it ever manifests itself is higly specific to the individual circumstances. Some of us older folk may remember when certain TV's would have 'noise' when certain hairdryers were used. If you had the TV yet no one used those hairdryers in your household, you never saw it.
Does it have a legitiment scientific place in discussions of (possible) audible differences?
Or does it contaminate the "Gospel"?
This is a quandry.
HMWT