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Which watts are the right watts in SS amps?

Hello Sports Fans!

More than a few people over the years on these pages have said only those SS amps which double down in output power as impedance drops are truly special or worthy amps. Eg., 200 @ 8ohms; 400 @ 4 ohms; 800 @ 2 ohms; etc.

Not every SS amp made does this trick. Some very expensive ones don’t quite get to twice their 8 ohm rated power when impedance halves to four ohms. BAT, darTZeel, Wells, and Ypsalon to name just a few.

An amps ‘‘soul’’ or it’s ‘voice’ is the main reason why I would opt in on choosing an amp initially and keeping it. Simultaneously , I’d consider its power and the demands of what ever speakers may be intended to be run with it or them.

I’ve heard, 80% of the music we are listening to is made in the first 20wpc! I’m sure there’s some wisdom in there somewhere as many SS amps running AB, are biased to class A Only for a small portion of the total output EX. 10 – 60 wpc of 150 or 250 wpc.

After all, any amps true output levels are a complete mystery when anyone is listening to music anyhow.

I suspect, not being able to actually measure true power consumption, the vast majority of listening sessions revolve around 60wpc or so being at hand with traditional modern reasonably efficient speakers.

Sure, there are those speakers which don’t fit into the traditional loudspeaker power needs mold such as panels or electrostats, and this ain’t about them.

The possibility of clipping a driver is about the only facet in amp to speaker matching which gives a person pause while pondering this or that amplifier.

I feel there is more to how good an amp is than its ability tou double output power with 50% drops in speaker impedance.

However, speakers are demanding more power lately. Many are coming out of the gates with 4 ohm ‘nominal’ IMPs which lower with fluctuations in frequency. Add in larger motors on larger drivers, multiple driver arrays, and on paper these SOTA speakers appear to need more power.

IMHO It is this note which introduces great concern.

I’ve read every article I can find on Vienna Acoustics Music. Each one says give them lots of watts for them to excel.

Many times good sounding speakers I’ve owned sounded better with more power, albeit from arguably a better amp.

I tend to believe having more than an adequate amount of cap power is indeed integral. … naturally the size and type of transformers in play possess a strong vote for an amps ability to successfully mate with speakers.

Controlling a driver’s ability to stop and restart is as well a key to great sound and only strong amplifiers can manage this feat. Usually this gets attributed to ‘damping’ factor, but damping as I read it is more a shadow than a tangible real world figure as it depends on numerous factors. Speaker cable length alone can alter damping factors.

A very good argument exists about those mega watt amps voices. Each 500 or 600 wpc amp or amps, I’ve heard have had stellar voices too, not merely more watts.

So is it predominately these mega watt power house amps souls or their capacities that fuels the speakers presentation?

Would you buy an ‘uber expensive’ amp based more on its voice or soul, than on its ability to output loads of watts, even if you feel the amp may be somewhat under powered for the application?

Choosing this latter option also saves one money as the more powerful amps do cost more than their lower outputting siblings.

Please, share your experiences if possible.

Tanks muchly!

blindjim

Showing 2 responses by stfoth

stfoth
435 posts
 
I still can't say I understand all of this, even as very knowledgeable and helpful folks are doing their best to dumb it down.  I get it that, oftentimes, a speaker with a high, flat impedance and high sensitivity tend to work well with high output impedance tube amps, SETs and such.  I also get it that a big, low-sensitivity speaker with wild impedance and phase angle fluctuations tend to work well with powerful solid state amps.  Some of this seems somewhat easy to discern when graphs like what Stereophile often puts out are available.

Under the assumption that I'm not going to blow stuff up, sometimes I try things that seem like mismatches.  Sometimes, it's obvious.  Sound is goofy and the woofer cones are all over the place.  But, other times, the sound is really, really nice, even if it may not measure well.

Or a low-power SET with a "mismatch" low-sensitivity speaker, but restricted to low-volume.

But, what about a common middle ground...speakers that generally vary from 4-8 ohms with moderate phase angles.  Mid-high power push-pull tube amps or SETs with huge transformers (e.g. Cary 805).

I get it that the frequency response may not be flat, but what else might be happening--good or bad?  Are we just making bloomy bass and hilly frequency responses?  Are we just making a personal decision on whether that is better than some of the nasties Ralph describes--high-order harmonic distortion, IM distortion, etc.?
stfoth
435 posts
 
Thanks, guys.  I guess maybe I like the Camry and what I think is good sound, with the full recognition that there is always better to be had, learned, and tried.  :)

Turning somewhat back to Jim's inquiry... Any merit to what seems like an easy way to navigate?  Just go with a big, quality Class A solid state with a nice voice that should work with just about anything?  I'm no somm, but I have more experience than most of my friends, so they sometimes ask.  I often tell them not to overthink it and just order a decent Champagne, especially on a date or in a group.  95% idiot-proof.

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