So I like to change my speakers from time to time – like all good hifi fools. I was sick of the crappy Kef C40 lumps that I got from freecycle and decided to splurge £100 on a pair of LNB Para-Lab-Supers. They were manufactured in April 1973 so that makes them just under two years older than me. Thankfully, they haven’t been drinking as much beer or eating as many pizzas as me so they are pretty much like new. They used to sell for £52.50 back when my dad had flares, which translates to about ~£600 in modern money. They are based on a ‘Labyrinth’ design featuring a KEF T27 tweeter and Elac 165mm long throw bass unit.
How do they sound? Well I’m not going to tell you that a veil has been lifted or that I’ve heard things in recordings that I’ve never heard before but I will say they are a LOT better than the Kef C40 floorstanders. This is mostly because they actually have some bass. They fill the largish kitchen-diner quite nicely thank you, and although old fashioned are actually quite smart. [UPDATE] After listening for a while longer I felt they were a bit boomy/woofy. I investigated and found that only the first fold of the labyrinth had any stuffing in it. My rudimentary understanding of this speaker design is that it usually has a consistent filling through the full length of the pipe. I used a basic ‘loft insulation’ style filling from an old sub enclosure that I had lying around and sure it enough it has tamed the wobbly bottom somewhat. It’s very hard to re-stuff this kind of enclosure as the pipe is too small for my hand and arm but I did the best I could and used an equal pre-measured quantity of filler on each speaker. At the request of Andy, a commenter on this post, I also took some pictures of the crossover. It’s a classic bit of Great British veroboard work, but does the job I guess.
I haven’t verified it but I’m assuming it’s a circuit design ala…
As I write this I’m listening to the solo from Kid Charlemagne by Steely Dan and it sounds pretty damn good to me – it’s also about the right vintage for these speakers. What’s driving them? Well, a poxy Chinese valve amp called Little Bear. ‘Nuff said.