What Power Amplifier Should I Buy?

@lynn_olson 

Thanks for the recommendation.

Gee, those are some expensive speakers. My budget is $5K. I need to stay near that price.

What is your opinion of the Revel f208 speakers? I bought them mostly because I liked the small bookshelf speakers they make (now in the lo-fi TV system that my SO likes a lot) and by Amir's g;lowing review on ASR.

Not interested in Revel, sorry. I would take Amir’s subjective opinion with a grain of salt, for the simple reason I have yet to meet any reviewer that has the same tastes as I do. I’ve been to their houses (not Amir’s) and didn’t like any of their systems. I don’t trust anyone’s subjective reviews. I'm out of sync with most of the industry.

However, that said, Amir’s measurements of pro monitors are right on the mark. Consider those first. They will have better dynamics than audiophile speakers.

I should mention there are hard limits on the dynamics of a 2-way speaker with a 8" woofer and 1" dome tweeter. The only dynamic step upwards is a 3-way with a 10" or 12" woofer, 4" midrange, and 1" tweeter. But ... unless superbly engineered, 3-ways usually have a poorer sense of coherence, or integration, than a 2-way speaker. A good 3-way is actually extremely difficult, particularly at a moderate price point.

2-ways are far easier (speaking from experience here). A good crossover and well-chosen drivers, and off you go. But getting coherence out of a 3-way is often difficult, because the midrange driver doesn’t quite match the sonic character of the woofer, and worse, the low-frequency crossover falls in a range where subtle differences in timbre are definitely audible. This is why 3-ways at audio shows often sound disjointed and incoherent, instead of like a single source or like a real musical instrument.

A (very) common problem is the 3-way will sound "right" and coherent at a fairly loud 85 to 90 dB show level, but disjointed and confusing at a 65 dB background level. Something to beware of in show demos ... how do they sound when the playback level is moderate? Is the speaker suitable for background music, or not? Big, complex, expensive audiophile speakers often fail this test.

So the choice between a 2-way and a 3-way isn’t as simple as it first appears, depending on your personal tolerance for incoherence. Once you learn what it sounds like, you can never unhear it, and your choice of acceptable speakers narrows quite a lot.

Historical note: Altec always designed 2-way systems if they had any choice in the matter, while JBL leaned towards 3 and 4-way systems. Part of the reason why the midrange is so different between Altec and JBL in their big monitors.

The brands I think of are horrible choices: ZU Audio and Klipsch.

@kevemaher I don't see any problem with the ZUs. They easily keep up with the studio monitors @lynn_olson was recommending. The Klipsch, harder to say; if you want the most dynamics you get one of their horn systems but as far as I can tell they are (IMO) entry level to horns. I should qualify that by saying I've not heard a set in a controlled environment for quite some time. I would not be surprised to find out they are using computer optimization in their horns- anyone who doesn't do that these days is missing a bet!

I'm a fan of horns also; they have controlled directivity so can be used to minimize side wall reflections which otherwise contribute to harshness and of course they are much easier to drive!

You might consider a set of Deadalus loudspeakers which are typically about 95dB (meaning you'll need about 1/10th the power to get the same sound pressure in your room as opposed to the speakers you have now) and are reasonably priced. There are plenty of other choices.

Kevemaher, I agree about the Zu’s. I’m not a fan of any speaker with whizzer cones ... mechanical crossovers have a whole host of problems that do not respond to electronic correction. (Mostly time-domain distortion and energy storage.)

The latest generation Klipsch Cornwall is actually pretty refined, but is way out of your price range. To be honest, there aren’t many good, efficient speakers in the $5,000/pair price range. Just finding a well-engineered 2-way, never mind the efficiency, isn’t all that simple. I lean towards British products like Spendor, but they aren’t cheap, and usually need a fair bit of power as well.

I admit I am quite biased because I design my own speakers and electronics, and do not follow the audiophile mainstream. I think the last commercial speakers I owned were KEF 104’s in 1975 or so. Everything after that was by my own hand, and I gradually moved away from the direction that audio took in the 1980’s and 1990’s.

Also, I don’t have the skills to design a speaker that hits the $5,000/pair price point. Value engineering isn’t my thing ... others are way better at that.

To loop around to the original question, you should try a 200 to 500 watt Class D amp and see if that meets your desire for more headroom. My guess is that it will simply expose the dynamic limitations of your existing speakers, but you don’t know until you try. How can you tell? Play the music you know well and compare to your existing amplifier, with no change to your EQ setup.

If you gain headroom, great! You just saved a lot of money. Pat yourself on the back and stop right there. Sell your existing amp and enjoy the brave new world of Class D amps. But ... if it’s your speakers that are the limiting factor, well, you need more efficient speakers, end of story.

And I feel really bad telling you that more efficient speakers might make you more dissatisfied with your existing amplifiers. More efficient speakers have a nasty way of exposing electronic colorations ... not just noise and hiss, but Class AB transitions and grain-n-grit as well. That’s why there is a lively market in the 8 to 35 watt power range.