Originally Posted by audioguy
The placement difference is in the rear subs. When I had SubMersives, the rear subs (two of them) were stacked in one of the rear corners. My 4 F18's are along the middle of the back wall . BUT, if use just there front 4 F18 subs, I still think the mid/upper bass of the SubMersive is cleaner. I can't test identical placement since I can't stack 4 subs in one corner but I could do 3 in one corner. I may test it sometime!!
I suspect the differences you speak of are either due to placement or psychoacoustic phenomena. There is also the driver orientation difference which could be a factor (slim chance though). You also have a different toolset now with the Trinnov but I remember you working on the F18 integration well before your move from Datasat.
Listening to both the F18 & Submersive HP (not +) head-to-head I found them indistinguishable up to the point where headroom became a factor. ULF advantage vs mid-bass advantage.
I also had the PSA S3000i at the same time as well. It was also indistinguishable at lower SPL levels. However, the PSA exhibited more THD and it became audible as levels were increased. It was not bad sounding in any way. Thicker is the best I can describe it. I'd bet a majority of blind listeners would prefer the PSA for movies and the Submersive for music.
As many know, Seaton and PSA both use variants of the Eminence Lab15. But each is customized. The Seaton variant is most likely more expensive as it is more linear ([sarcasm]what a revelation, huh?[/sarcasm]) across the board. Not audible, but measurable even at lower levels.
Many know that the F18 utilize the Dayton UM18 but Mark does not purchase from Parts Express. The drivers utilized by Seaton must adhere to a more stringent set of specifications. A F18 will play lower and louder than a similar DIY UM18.
I know you already know most if not all of this. But, I still read posts saying Seaton buys from Parts Express or PSA uses the same drivers so I feel compelled to highlight the true differences.