the big Spendors have a slightly humped up bass response (not severe, but definitely there) which needs SPACE around them in a US style timber-frame room to balance right (many studios have a drier and leaner acoustic to a domestic environment I'm told). The polypropylene mid driver will give that Spendor "organic" quality but with slight loss of very fine details - IMO. The passive crossover won't help either..
As with new Spendors, a BIGGER Naim amp with perhaps some silver-plated copper cable of good gauge (we used Chord Odyssey to advantage with Naim's full awareness, as well as the good-n-crisp toned A5) should be fine. A Nait will clip IMO and the complex load from the three-way crossover won't really help - IMO...
The SP100's have a slightly better bass IIRC and the current updates have fine-tuned a now 20+ year old speaker..
My preference would be for some Harbeth 40.1's. Bang up to date driver technology, hours of testing and listening and a warm, but such a clear toned speaker which can be driven by almost anything - you choose... HiFi dave's demo pair coped with my Crofted Quad II's with no complaint, apart from losing deep bass and high treble when compared to the awsome and affordable Series 7 power amp.
In the UK, I've seen the odd pair of S100's go for very few hundred quid and this must be a great bargain IMO. Just PLEASE get an amp with a little bit of damping factor to hold the bass together and allow the midrange to shine...
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