Re: High Frequency Compression Driver Evaluation
Jeff,
Nine of ten DH1AMT I have used since 1992 are still probably all within a few dB of each other, and their response still looks like the published charts.
One pair looked a bit different, after cleaning the gaps and swapping the diaphragms between the pair, both looked better but the "most different" response followed the diaphragm, rather than the driver.
Diaphragms made at different times may have slight differences, and drivers that have been dropped may loose some magnetism, a dirty old road system probably would show more differences than a system that had light duty hanging in a church.
When taking pictures of the drivers, I found rocks and dirt to have enough ferrous content to stick to the magnets. Systems used outdoors in windy dusty conditions could collect enough particles in the gap to change response.
