Dev said:
Tannoy DC range (i.e. DC100 and DC200) wasn't perhaps their best effort but the DC is an abbreviation often used generically for Tannoy's Dual Concentric speakers. This practically covers the entire Tannoy range (over several decades) apart from their lower range stuff. You are surely not suggesting that all DC speakers are dull, from their monitors to Prestige range to Kingdoms. (IYHO

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Hi Dev!
Putting aside my personal view of the Tannoy sound...you will find that there is more commonality than difference between the various generations of Tannoy dual concentric drivers.
The hf compression driver and associated flared horn have changed little since their inception(including the nasty little kink in it's frequency response around 1.2kHz) hence the signature of the sound you hear from 1.8kHz onwards is pretty much the same for all the hf units. This equally applies to the three way systems like the Buckingham & Dreadnought as they both use the same hf unit...
You will find a tightening of the bass sound as the generations moved forward in line with improvements in manufacturing technology v-a-v the cones and surrounds(including the plastic cone/rubber surround domestic variants - introduced for lower cost purposes)...the spiders have remained essentially the same barring doping materials. Likewise the voice coils...
The passive x-overs all follow the same form...even the "active" XO-5000 used low level passive x-over modules of the same form as the high voltage ones. The main XO-5000 difference being the inclusion of an active variable time delay, active eq, phase switching & active variable gain on the various channels.
The main reason for the dc driver based system popularity in the film, broadcast and recording industries was this very consistency in sound, in that you could record material in one studio, say in the UK, and then go to, say the USA, and provided the other facility had Tannoy dc based monitors, the mix down etc was done on a common monitor sound reference.
From the above you can discern that the Tannoy dc sound is partially intentionally, partially technologically stuck in a time rut.
To me this greatly defines the "dullness" that I refer to - to others this represents the "uniqueness" of the Tannoy sound. Speaker technology has greatly moved forward in the hands of other manufacturers who do not have these constraints.
IMHO :MILD:
Have fun...
Mark