I built some 2-way speakers using dayton reference paper woofers. Just got the DATS V3 and tested them out. Surround speakers use 7″, center uses 6″ and fronts use 8″. All the tunings seemed to be making sense except for the 8’s. I dont have the data in front of me but they came out tuned lower than expected. The port is an uncut tube from parts express. 2.5×8.5 I believe and the box internal is just less than a foot cubed. About .94′ they tuned around 34 hz. The only thing different about the 8’s is the foam damping material on the inside back wall is higher quality thicker material with the 8’s. Any ideas as to whats going on?
Also, when testing frequency response with REW. There is a dip around 660 hz. It shows up on the DATS as well. The boxes are approx 9.25×10.25×18. The longest dimension is unbraced and the woofer lies in the center of baffle. Possible standing wave or cabinet resonance.. im not sure.