Dynamic compression in speakers themselves?

@mtrot

No. Extreme high sensitivity is no guarantee of unrestrained dynamics. 91 dB to 94 dB is already plenty of sensitivity. It is the driver design that is important - large voice coil, massive magnet, short coil in long magnetic gap.

12 inch woofers are a minimum but make sure they are pro woofers. Only these designs will give you dynamic crescendos with ease. 

A lot of sensible things have been said thus far. Do not forget the amplifier part: for great dynamics you need a beefy (solid state) amplifier. A few hundred (pro audio) watts will do no harm.

Full range horns ( I listen to Klipsch Lascalas, modified, with subs ). Some excellent hybrids available.

Do not forget the amplifier part: for great dynamics you need a beefy (solid state) amplifier.

This statement isn't true. What you need is a competent amp and it does not matter if its tube or solid state.

The match between the amp and speaker is pretty important.

Perhaps a conversation about 'dynamics' is in order.

In most audiophile conversations, the word 'dynamics' usually indicates 'distortion' and you can usually substitute the latter for the former without changing the conversation.

SETs, the least powered tube amps around, also tend to be the most 'dynamic'. This is due to the fact that when you push the otherwise very low distortion SET hard, the higher ordered harmonics used by the ear to sense sound pressure start to show up. On transients.

This causes the amp to sound 'dynamic' and if you look at the reviews, its common to see that SETs sound far more dynamic than they should for their low power. Its distortion interacts with our physiology to create the illusion of 'dynamics' but if you place a sound pressure level meter in the room, it will show what is really happening.

But the truth of the matter is, tube or transistor, if the amp is *not* making distortion, its dynamic contrast will be the same.

So if we are talking about an undistorted signal, then the fact that the system can play to higher volume levels without strain is a big deal. You can do that with tubes or transistors. My system can easily play to 110db and I have only 50 watts/channel. But if you have really inefficient speakers you will need a lot more than that.

@mtrot --

I guess I should clarify that I’m not looking for high SPL playback. I’m just looking for that big, relaxed, open, uncompressed sound. I want dynamic crescendos in classical music to get my attention, but with a sense of ease, if that makes any sense. Should I gather that I should be looking for high quality floor standing speakers with ~12 inch woofers and at least 96dB sensitivity?

I’d look for horn designs mainly (hybrids or all-horns), with large radiation areas. Or as is suggested by posters @mrdecibel, @atmasphere and others.

@shadorne --

No. Extreme high sensitivity is no guarantee of unrestrained dynamics. 91 dB to 94 dB is already plenty of sensitivity. It is the driver design that is important - large voice coil, massive magnet, short coil in long magnetic gap.

12 inch woofers are a minimum but make sure they are pro woofers. Only these designs will give you dynamic crescendos with ease.

There’s more than one way to skin your cat. Bear in mind that ATC speakers are not particularly efficient, so they need large voice coils, massive magnets, a lot of power, etc. to deliver with ease in the entire SPL-range within their specific design limits. Their active iterations is a big plus as well, with the drive units being coupled directly to their respective and dedicated amps. All active ATC speakers are dynamically very capable and can be pushed hard before beginning to lose their composure, but it’s with the bigger models from SCM100 and upwards that ones ears is likely to give up before the speakers begin to show any signs of stress. To my needs in a stereo setup the capability to reproduce with ease at even the highest SPL’s is one of the major factors of importance, and the reason why I seriously considered purchasing the SCM150 ASL Pros’s (before choosing horns instead) - which are close siblings to your speakers, @shadorne .

That being said very high efficiency speakers at +100dB’s don’t necessarily need large voice coils or massive magnets (though they’re mostly pro units anyway, and therefore more rugged than your typical hifi dittos), the former of which can even be counter productive used in conjunction with horns in the effort to maintain their traits here in regards to transient response, "snap," etc. A 10dB advantage in efficiency equates into 1/10 the amount of wattage needed, and with many if not most conventional hifi-designs there’s even a 15-20dB shortage in efficiency compared to high efficiency speakers at 105dB’s - which is up to 100 times more watts required for the former to deliver the same SPL. Most any 105dB efficiency speaker design IS guaranteed to provide ample dynamic capabilities in any situation, giving you 105dB’s (at 2 meters/6-7 feet distance) with just a single watt - think about that; 105dB’s is way loud (enough in most situations, I’d say), and with a single watt required will keep distortion levels and thermal issues at bay.

From my chair high efficiency is paramount here. This also provides the freedom to explore smaller-watts tube amps, the SET’s of which in particular are extremely capable within their first couple of watts in delivering dynamics and aliveness that to my ears leaves most SS amps in the dust.