DEI and PP100's where all made by HG just rebranded. They basicly made endless versions until they got a decent product and used DEI and PP100's as their dumping grounds for early designs. That is how I heard it anyways.
The problem is lack of documentation no one can tell you what interchanges with what so unless you have exact matching version stamped on lid DEI and PP100 means nothing zero interchangeability from one revision to the next and zero paper trail.
If you have a device that uses DEI or PP100's your only realistic practical choice is to repill the entire unit with brand new matched HG 2879's. Save the old PP100's or DEI's and match them all and use them to build a smaller amp.
The problem is lack of documentation no one can tell you what interchanges with what so unless you have exact matching version stamped on lid DEI and PP100 means nothing zero interchangeability from one revision to the next and zero paper trail.
If you have a device that uses DEI or PP100's your only realistic practical choice is to repill the entire unit with brand new matched HG 2879's. Save the old PP100's or DEI's and match them all and use them to build a smaller amp.