There's little doubt in my mind that a really motivated individual could probably achieve a pretty close facsimile reproduction of the Grado flat pads.
Apparently, hot-wire cutting works well for both rigid and soft foam. In theory, that would mean that reproduction earpads could be fabricated from suitable slabstock foam versus the molded foam process.
From what little I've read, the quality of the cut is determined primarily by the temperature and speed of the cutting wire, and can achieve a high level of precision.
Of course, an individual would have to identify a source of matching foam stock unless the current Grado OEM bowl pads are large enough such that they could be used as raw stock.
An individual would also have to design and build a jig or template for each type of cut that would be necessary for the earpad fabrication.
Personally though, I'm completely sold on modded RadioShack #33-379 pads. Altogether, I've bought eleven pairs of these. Seven pairs were eventually sacrificed in the name of science while trying to find the optimal hole size and perfect my cutting technique. The sonic benefits compared to the OEM bowl pads include:
- increase in apparent loudness
- astonishing increase in detail even at remarkably low volume levels
- increase in bass and 3/4 tones
- low cost and non-destructive
On the negative side, there's probably some slight decrease in soundstage (spatial width and depth), but considering the benefits I barely notice or miss that.
TravelLite