Lawton Chambers for TH610!

[charleski]

I've taken multiple measurements and whilst from 300hz and up they can vary very slightly, the characteristics of each chamber are present, especially below 300hz and also upto about 3k where the weird EARS resonances take over. I also did multiple calibrations L/R at 70/100 and 1K for each test to ensure equal level and placement for the sweeps you see above. So no point wasting time on multiple positions for every headphone since the reason for getting these is mostly for the increase bottom end response. The biggest differences are between the Black Limba which is more V-Shaped, the Wild Ziricote which is more HD600ish (still more bass though) and the Wild Chechen/Flame Marble Walnut are similarish but Chechen is a bit cleaner and brighter sounding.

You're just needlessly introducing confounding factors. Take one pair of headphones and test them with the stock cups, then switch to one of the Lawtons and retest the same pair. If you're having problems with 'weird EARS resonances' from 3kHz up then plot multiple sweeps with independent seatings to see if these average out, though I strongly suspect that most of the differences you're seeing there are simply the result of inter-unit variation.

It's clear that the Lawton cups are larger than the stock ones, and the change in dimension of the rear cavity (looks to be about twice the volume) is probably the primary cause for the increased bass response. The Ziricote is the odd-man-out and warrants another look - check that it's sealed against the frame properly and you don't have a leak.