Kef 107 vs 107/2

Running my 107s with McIntosh MC252.......a match made in heaven....additionally I utilize a fully balanced KUBE....very rare bird indeed!

I presume that if you cross the 107s or 107/2s to a suitable sub below 80 Hz the KUBE is not needed; is that correct? I have a KUBE designed for use with 104/2s that I have never used, because I cross my 104/2s below 80 Hz to my Velodyne HGS-15. It seems logical to me that freeing the KEF drivers from very LF excursions can only enhance their airiness and transparency above the cross over. Although the 104/2s excellent full range speakers, the sub adds LF extension, noticeable especially with low pedal notes of pipe organs. The 104/2s seem to loose a bit of airiness when used full range with the sub, so I always cross at 80 Hz.

db

has anyone ever tried to upgrade the crossover on the 107. With the vast improvement in semi conductors .....there should be some audible differences......

i have the 107 and the 107/2... i would like to upgrade/ modify my 107 to become 107/2......Has anyone ever attempted?

I've had 107/2s since the early nineties (replaced my AR9s). I think the differences between the 107 & 107/2 is mostly attributable the KUBEs each use. I listened to both versions when I was shopping (the dealer had older ones still in stock), and I recall thinking the /2 was worth the price difference (around $500, IIRC). KEF claimed the only changes were a new tweeter, bi-amp ability, and the design of the KUBE... my suspicion then, as now, is that the KUBE makes the biggest difference. I listened to each, with, and without their KUBEs, and the older model sounded worse in the mids & highs, with the KUBE. The newer model sounded almost exactly the same with, or without it's KUBE... except for the improved base, of course. I wouldn't use my 107/2s without the KUBE, if I had an older model, I'd look for a newer KUBE!
Also, it should be mentioned that any 107s are going to need new woofer surrounds by now, even the last of them are certainly cracking. I just redid mine a few weeks ago, and I should have done it a couple of years ago! A properly working pair of 107s (with the KUBE) have AMAZING base that IMHO can't be beat for less than $10k.

responding to Kenwood700cmt:

recently I have upgraded the MF/HF xo to Solen caps, replacing the stock Alcaps and adding a bit of Cardas Quad Eutectic solder to all contacts: as expected, the sound stage widened and everything is clearer. Maybe I should replace the internal wiring with something better. I am sure replacing the caps in the LF xo will tighten up the bass but I am pretty happy with that already.

After so many years, I suspect that the fluid in the T33 / SP1210 tweeters have started to dry out (havent noticed the drop but it may happen so gradual that I didnt notice or I am just getting more deaf). I wonder if anyone has tried to upgrade the existing ones to ScanSpeak 9300 or 9500 (which have a very similar frequency plot as the T33) with satisfactory results. If anyone has new old stock of a pair of Vifa MG27 and want to sell them, please email me, thanks!