Eminent Technology LFT8B’s reversing woofer polarity


Hi,

I have a pair of the Eminent Technology LFT8B’s and read Dr. Robert E Greene review in the Absolute Sound magazine (2014 I believe) of the speakers where in the review he reversed the polarity of the woofers and said it made a significant improvement. He was going to give the speakers a mediocre review (his words) before doing this and after reversing the woofer polarity he then said they were significantly better and proceeded to give them a rave review. Have any LFT8B owners out there ever tried this? Thank you.

Scot
scothurwitz
Hey bdp24

Thanks for the explanation, I’m sure I would have eventually figured all that out, only problem is I would have been 5 years older! Does Rythmik sell this sub already built? I would like to hear one. The other sub System I would like to hear is the “Swarm”. Thanks again, very interesting. Take care

Scot
No Scot, both Rythmik and GR Research sell the OB Sub as a kit only. But the Canadian woodworker offers his H-frame fully assembled (and finished if you want) in addition to shipping it as a flat pack. To see what it looks like, look up the Virtual System of Audiogon member kennythekey (using just "kenny" as your search word). Kenny had his frames built and veneered by the Canadian.
Not to hijack this thread, but many thanks to bdp24 for all your past posts about the LFT-8Bs -- I ended up purchasing a new pair a couple years ago from someone who purchased them but never ended up using them due to life changes (lucky find).  Funny side story -- the dealer he purchased them from mixed up the boxes for the matched pair of panels and woofers (they come in separate boxes).  I ended up with a new, but unmatched pair, and when trying to assemble them, the predrilled holes were too far off to make the connection, but too close to be able to make a clean new pilot hole!  The woodworkers and DIY guys will know what I'm talking about... SOOOO, before I could even hear these I had to spend some analyzing the issue, which led to some careful application of plastic wood and re-drilling... thank goodness I came into with with a woodworker background, so I was able to correct the issue cleanly -- lol, do we all go through this stuff, or am I somehow in debt to the karma police?

Anyways, what an incredible set of speakers.  When I was researching, I was on the fence between these and open baffle designs -- mainly the current offerings from Spatial.  I still would like to compare these to some Spatial Sapphire M3's someday, and would be highly interested in reading the opinions of anyone who has any about this, or even better has perhaps heard both designs.  

To my ears, and this is coming from a fairly long and varied experience with other very nice speakers, these are nearly perfect for my tastes.  The imaging is one of the things that people sometimes mention is just sort of mediocre, but in my case I'm finding it to be totally holographic and pinpoint accurate, while also being large and immersive... shrug.  They are *very* sensitive to placement -- micro adjustments in any way can bring a notable change.  Finicky position tweaks and experimentation has been a large part of my history with these, but I don't find this to be a fault in any way of the speaker... I look at it as the added care needed for adjusting and maintaining a precision instrument -- it needs more finesse and care than a generalists tool, but once set up properly, it excels.  A high level racing bicycle requires more careful alignment of all parts versus an el cheapo mountain bike, for example.

My one complaint, in my system, has been in regards to the treble.  Sometimes it's just a bit forward and hot for my ears, and I find it can be a little bit fatiguing.  However, I'm admittedly prone to being sensitive to this.  The effect varies widely from recording to recording, and I don't have other 'spare' high end gear on hand to mix-and-match to run a process of elimination.  I'm left wondering if it could be how they play with my upstream components, or some untamed room brightness exacerbated by the nature of the dipoles, or just the nature of the speakers.  It could also just be the mastering of the recordings themselves.  Maybe these are SO honest and revealing, that any harshness in a recording can easily grate on the ears.  It's usually in the mid to upper treble region, where saxophones, female vocals, electric guitars, and treble-leaning synths commonly venture.  I do only have a few diffusion panels in an otherwise fairly bare drywalled room -- maybe the answer is to add some carefully placed absorption panels.  Even though the speakers are almost 5 feet off my front wall and a few feet from the side walls, I could still be getting too much bounce.  It would help be to know if anyone else who knows or owns the LFT-8Bs has experienced this same 'peaky treble' - ?

Otherwise, I'm happy as a clam in audio nirvana... (are clams happy?)...


My tech disconnected the tweeters and placed the speakers with the tweeters facing the outside - they sound and image much better. 
His own speakers may have had their phases reversed. Subwoofers can be tricky. If you are crossing down low without a full two way crossover and your main speaker's bass is on the fat side it may well sound better with the phase reversed. Back in the day with dipoles there was a strong movement towards wiring subwoofers out of phase. If you are crossing under 80 Hz with a full two way crossover running a steep slope you will have to go back and forth a few times to pick up on the difference. Crossing up at 100 Hz the difference is very noticeable.