Ill try and answer this in order from the quotes above.
A. Does Epik even have any "higher" level products?
Can you tell me what the T/S parameters are? WHat size and material the VC is made of? SHorting ring if any? Cast aluminum basket? No, I can tell you Epik's Empire sub uses a pair of pretty cheap drivers that feature a generic stamp steel basket, foam surround, Im not sure what the voice coil size is or what its is made of but Im sure its a kypton former and not aluminum. Here is a link:
http://epiksubwoofers.com/empire.html Scroll down to the "drivers" section. Not exactly a high end unit and no T/S parameters are given either. I mean for $799 what do you expect? 2 drivers opposed in a small enclosure to minimize shipping costs and a class D chip amp.
And this is just one example. Same can be said for HSU..........show me some T/S parameters from HSU's website.
HSU is basically all marketing..........and please explain to me what HSU's "best in class" marketing bull is supposed to mean? LOL! Its a joke.
WHat do you REALLY KNOW about the HSU front firing driver? WHat is custom about it? T/S parameters? Pictures? Breakdown of its design and materials used? Funny how none of that stuff is kicking around isn't it?
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Use your common sense here is all I can say.
And a pulp cone reinforced by kevlar or nylon or a composite of some type is pretty generic these days and very common. Don't let em fool you? Nothing exotic about the driver HSU or Epik uses as an example.
On the amp section. CLass D chip amps are extremely efficient and they are absolutely DIRT CHEAP to mass produce. Mfg's use them because they are dirt cheap to produce, efficient in power usage(so 1000 plus watt amps are common) and work well in subwoofers because the lower frequencies can easily mask the natural SQ deficiencies of most class D amps.
Analog class A/B and G/H amps on the other hand are significantly more expensive to produce. You just don't see many subs with them these days. ANd with the trend towards subwoofers needing a kilowatt of power or more its more practical and much less expensive to make a small compact class D chip amp than a good analog amplifier of the same power. Rythmik's 600 watt Class H(basically a much more efficient class A/B amp with variable voltage rails)plate amp weighs about 25-30 pounds on its own. Its extremely heavy for a sub plate amp.
And yes eD does disclose alot of info on their drivers. Their drivers are decent. I owned a few different ED HT subs, but I just wasn't really impressed with their performance(surprisingly the sealed ones). THe plate amps they use just plain suck and are not relaible at all IMO. Of the 2 pairs I owned over the course of 3 months I had one DOA and 2 failures. And I am the type who keeps the gains very low and does not over drive a product to get output. If I need more output, I buy and daisy chain another sub into the mix.