Nice comparison, but it really helps to use paragraph breaks in order to make your writing easier to follow. Here is your post, but now including paragraph breaks:
"I recently purchased a kef kube 12b - not the newest MIE (although I don't think the dsp changed much?) and wanted to compare it to my previous subwoofer the presonus temblor t8. This may help someone like me who couldn't find any similar comparison before purchase.
1st off, I listen to 100% music, no movie watching. My listening area is 16 x 13 feet but open to the rest of the house - no closed doors, small house 800 sq foot. Music is usually loud enough that you have to speak loudly over, but don't have to shout over. The presonus is ported, 8 inch down firing woofer, class AB 100 watt rms. I have used this sub for about 3-4 years with Audioengine HD4 speakers and a brennan preamp 3.5 audio out originally to rca into presonus and rca out of presonus to the audioengines, later 3.5 out split to rca to presonus and rca to audioengines due to audio outs of presonus working intermittently.
By the way, music out of the small speakers improved noticeably after not going through the presonus first. Presonus low pass crossover set at 95hz, gain at about 2 oclock, high pass filter switched off. The presonus has always been loud enough for me - somewhere the general output was published as 104db I think. The bass never seemed boomy or flabby or slow or one noted or any other such descriptors. music is mostly jazz and classic/folk rock. No classical, no dance or club music. It has sat at the front wall of the listening area to the left of the small speaker in a "corner" formed by the wall and a sideboard that the tv, speakers and assorted plants and junk sits on. Listening area is a couch on the opposing wall about 11 feet from the speakers. The ceiling is pitched from 8 foot to 10 foot. The floor is wood floor over subfloor over insulation over a three foot crawl space.
After unboxing the kef kube, I set the gain at 12 oclock and the crossover at 95hz and the dsp to in room, (three options are in room, wall, and corner via selector switch). Using tracks I know well, I picked songs that are recorded with just a little too much bass for my taste and set the gain right at the tolerable point - where I can still enjoy listening to the song - this way I can set the gain and forget it, as preferably mixed songs have just the right amount of bass volume.
And first impression was, meh. First off - at the volume I normally listen at, the kef seems no louder overall than the presonus despite bigger size, bigger driver, and 3x as much power. I ended up with gain at about 2 oclock for the right volume match to the audioengines. At 95hz or lower crossover, there seemed to be too much space between the subwoofer and the small speakers. I could not locate the sub in a soundstage sense, but the bass content was too separate from the smaller speakers in my opinion. After some fiddling, setting the crossover at 125 hz gave the same blend with the audioengines that 95z on the presonus did.
After a couple of listening sessions, it seems that the kef is ever so slightly more detailed sounding than the presonus. Even with the preferred crossover setting on the sub, there still seems to be a bit of separation that results in a sense of contracting of the lower hz content - what some may call bass sounding "tighter", and thus faster transients are rendered a bit better on the kef than the presonus. Both subwoofers produce palpable bass, even at low volumes - I dont know if this is room pressurization, or slam, but I know that I can feel the bass even at low volumes even at the furthest points of the house from the subwoofer.
Am I happy with the KEF? yes. Is it much better than the presonus, no. The reason that I went looking for another subwoofer is that the rca outputs on the presonus were crapping out on me, and sometimes the presonus wouldn't produce sound unless I fiddled with the input jacks - that's why I was avoiding another presonus and thinking I may as well upgrade.
My exhausting research on the subject narrowed down my prospects to the kef, rythmik L12 and Bk xlls 400. BK would have given me some of what I was used to with downfiring driver and class AB, Rythmik would have been excuse to try out servo, kef had more than one mention of being "cleaner" sounding than svs sb2000 and was chance to try out dsp sub. KEF 10b had pretty respectable output measurements on sweetchaos, Rythmik only posts 20hz info. I didn't like it that BK never responded to email regarding tax and shipping question, Brian at rythmik said their 12 inch sealed subs wouldn't be enough for me, and I got the KEF for $764.
At the end of the day, I think all of these subs are usually judged at the extremes of their performance - how much output and how low they go. These will never really be factors for the way that I listen to the material I listen to. This gets me to the why of posting this thread - If the kef had cost $1,000 I would have either not bought it in the first place, or returned it. I got a good deal and I have a small mixing room that I plan on using the presonus in. If you are someone that listens to music only, at moderate volumes then I would say the presonus is plenty of subwoofer at less than half the price of the kef. I could spend more money and never listen below 35hz or above 75db."
