Just an idea, dnapster or i mac/book some priest or iron maiden into your system. Try turning up the volume on the notebook or source. I personally have very good components, probably better than necessary for the Black Sabbath. Bel canto Amps Bridged to 400 wpc with Bel Canto pre-pro, and jolida tube cd. Although you may not get the exact imaging so popular in classical you can determine whether or not you really need to spend more $$$ on gear to drive the speakers etc. Also if you get some really good downloads, buy a device from Harmon Kardon from e-bay for the incredible price of $4-$12 yes that is $12.00 significantly less than one ben franklin which allows you to go from Computer to usb, then get a DAC (with USB), you will probably have to buy a non recognized audiophile brand, something more along the musical line, go to your local guitar center, (they probably have the unit I am speaking of for $150.00.
Still need more volume, duplicate your speakers, (buy another pair same manufacturer and make with matching amps). If you really are a black t-shirt guy then you know that the late Steve Clark (awesome guitar for the leppard until he rock, rock, till he dropped), and Mick Mars use more than one Marshall Amp. I guess what I am trying to convey is that if you want live metal kick, then wire the system like a concert not the San Francisco Phil Harmonic (spend the money where it counts). Many audiophile experts will criticize this post with all sorts of advice on what they would do, but utlimately what is important is how your system sounds to you. They also probably don't know that Motleys Too Fast for Love was produced for less than 50K, in fact I think it was recorded for less than 12, (what I am saying is that the original masters and live music will never have a controlled room jazz feel, most gibson, fender, or ibanez hard rock guitars are wired to Marshall(my guitar center friend calls these the kings of the distortion amps), thus for metal or anything in my opinion louder than Bryan Adams,to buy speakers with ridiculously expensive tweeters, which you may replace later due to blowout from super loud guitar solos might not be the thing to do. If you must amp how about two bel canto ev0-4s used, bridge them to 400 and then bi-amp, yes that is 800 watts per speaker, just be careful with the volume or you will be buying new speakers, or just buy one and use it for the bottom. It could be a versatile solution if you decide to go to two speaker pairs. I also agree with the db explanation for speakers. Let me know what you find out through experimentation. FYI, I have never had long hair, am a college graduate, and drive a ultra yuppie m3 beamer. I just know what I like to listen to when my wife attorney leaves the house on Saturday to go to the grocery. Rock On and please don't hesitate to respond if you need more help.