Power Question for Experts

It's been a LONG time since I've read it, but that sounds similar to what was in his True Signature subwoofer white paper.  It's where he was trying to explain how his amplifier produces 3600 watts of power.

I don't know if I would consider lower efficiency a bad thing.  Consumers are demanding smaller enclosures without giving up low end extention.  You MUST give up efficiency to do this based on Hoffmans Iron Law.  But since the cost of power is getting lower, it isn't a bad thing.  (BTW, I love my HK receiver)

My boss was designing a crossover for a coaxial speaker for a customer last week.  He did what he could with the crossover, but even still there was a large and wide dip in the upper frequency response.  It made the speaker lose a lot of crispness, and made it sound thin.  He could have fixed that by dropping the rest of the speakers response to match the dip.  But that would drop the speakers efficiency too much which the customer wouldn't want.  So in the name of efficiency, we had to give up the quality of sound.  That's like Bill Gates working by candle light because he wants to save money on electricity. 

BTW Dave, congratulations on the promotion.  If you ever find yourself up here in Seattle, you MUST stop on by.  It was great meeting you at CES, but it was way too short.

Steven Kephart

Adire Audio

Fun thread.  OK, brands first:

kfr01, for surprisingly good sounding and well designed gear on a reasonable budget, look at Outlaw Audio.  Their HT preamp is superb, and their amps are very good at a nice price point.  I also really like Rotel and want to try out their new HT receiver soon.  Bryson makes some nice amplifiers but are not not in the top tier IMO for their cost.  If you are really serious about clean power and want a stack of seperate solid state amps, look at the pro lines from QSC, Crest, BGW or Crown.  Back to HT, for a few dollars more you can't go wrong with B&K.  There are of course the super expensive esoteric lines like Krell, Levinson etc. but I don't think that's what this thread is about.  The Anthem line is nice although Paradigm's pre-amps are a but thin sounding to me.  In the more commercial receiver lineup HK is probably tops in terms of SQ, and as far as good quality and plenty of flexibility you can't go wrong with one of the better models from one of the big three: Yamaha, Denon/Onkyo, or Pioneer Elite.

I have always really liked Bob Carver's amplifier designs.  I still use one of his 33-year old Phase Linear class A amps for my stereo.  Speaking of inefficiency, you can fry eggs on it after a few hours, but it is clean and I have tested it at 470 watts without clipping and at 1% THD.  I have one of the Carver 400 watt mono magnetic power amps which was a nice toy but the power supply died and I never got around to fixing it so it's now a very heavy paperweight.  I really love the sound of my Sunfire gear and think the Theatre Grand preamp is killer, but Sunfire has been plagued with lots of quality control problems in the past few years.  I also used to run the "Ultimate Receiver" ans while it sounded great, it was pretty hard to set up and use and Sunfire kept issuing software and firmware updates which was annoying, which is why I went back to seperates.

Power.  For most home theatre or stereo listening (unless you have a really large room) 100 watts per channel of clean power is all the average person will ever really use.  Subwoofer amps can stand to be larger, in the 300 watt range, since it simply requires more power to push larger soundwaves around.  Now, that does not mean that 100 watts per channel is all the amplifier you might need, just that most folks are unlikely to use more than that (unless they are running really inefficient speakers.)  Headroom is a good thing, so sizing your amp with at least 25% head room is wise.  The person who said 300 wpc is the best setup is neither right nor wrong as it is totally dependent on the application.    Speaker efficiency is overrated IMO as a criteria for selection...

Here's a rule of thumb for you.  Whenever a manufacturer rep tells you that you absolutely need something, and then backs it up with scientific sounding arguements, and then proceeds to show you how they have EXACTLY the right gear to solve the problem, beware.  I cannot tell you how many spurious arguments I have heard exactly like that.  The truth more often than not is NOT that the gear was created to solve a "problem" but the argument about the "problem" or the "need" was developed AFTER the gear was created to justify the cost of the gear.  it can be a sales tactic that people inside the company begin to believe as some kind of "truth."  I saw it at Creative Labs all the time when I was there.

I need coffee, it's early here in CA.  More later. 

I don't want to say exactly which speaker it actually is because I can't be seen as talking bad about another company.   So I will provide hints for someone to figure out.  It is a coaxial speaker with the tweeters motor inductively coupled, is pretty much water proof, and is really easy to poke a hole into the cone when mounting it for testing purposes (damnit).  I do not know if the voice coils are coincident or not. 

Steven Kephart

Adire Audio