How important is the efficiency of a speaker to you?

Not particularly important to me.

The amplifier takes time to make this power (i.e., slew rate). So the amp "slews" 3.16 times faster to reach the same volume level resulting in increased dynamics for the high efficiency speaker.

that's not how it works, that is not how slew rate factors into how an amplifier works. Slew rate is directly related to bandwidth, not how quickly it reaches peak power operating within it's specified bandwidth. 

 an amp operating withing it's specifications that is  producing  100 W RMS at a given frequency will reach peak power in  the same amount of time as a 1 W RMS amp will.

Example.... at 1000 Hz the period is .001 seconds. So starting at zero crossing  it reaches a peak  .00025 sec later , crosses zero in the opposite direction at .0005 sec, the opposite peak at .00075 sec, and back to zero at .001... no matter how much power it is producing..  If it didn't it would be distorting the signal. 

@danager 

Thanks for posting the link. 

@herman Would that be in Denver or NYC?

Efficiency is not the issue, unless you have a silly pea watt amp. What you like to listen to is the issue and speakers, being the most difficult of all components, are always a compromise. I'll only listen to Line source dipoles. They are usually not very efficient. 

I have been using for 39-46 years the following:

- Altec Lansing 604Cs: 101db efficiency, 26 ohms. 
- NYAL Julius Futterman OTL3 monoblocs, converted to triode, about 135 watts each. 
 

theaudioatticvinylsundays.com/about

"an amp operating withing it’s specifications that is producing 100 W RMS at a given frequency will reach peak power in the same amount of time as a 1 W RMS amp will."

You missed the point. I said ALL OTHER THINGS BEING EQUAL. So the same amp, be it 1 watt or 100 watts, is used with both speakers.

Obviously a 100 watt amp will produce 1 watt (0.278 times the voltage) quicker than it will produce the full 100 watts.

Even a perfect square wave has a "rise time" and obviously it passes through 1 watt on the way to 100 watts.

"an amp operating withing it’s specifications that is producing 100 W RMS at a given frequency will reach peak power in the same amount of time as a 1 W RMS amp will."

 

You missed the point. I said ALL OTHER THINGS BEING EQUAL. So the same amp, be it 1 watt or 100 watts, is used with both speakers.

Obviously a 100 watt amp will produce 1 watt (0.278 times the voltage) quicker than it will produce the full 100 watts.

I’m sorry, but your understanding of slew rate and how it applies to how an amp operates is simply incorrect. Slew rate describes how fast an amplifier is capable of changing, not how fast it is changing. It describes the maximum rate of change, not how how fast it is changing for a given input

The point is, slew rate has absolutely nothing to do with efficiency or how dynamic a speaker is or anything being discussed here. Your concept of slew rate is wrong. Sorry if you don’t get that.

@herman Would that be in Denver or NYC?

I have absolutely no idea what you are talking about

"I’m sorry, but your understanding of slew rate and how it applies to how an amp operates is simply incorrect. Slew rate describes how fast an amplifier is capable of changing, not how fast it is changing. It describes the maximum rate of change, not how how fast it is changing for a given input."

I understand this.

So then, you are saying that slew rate has NO IMPACT on how a speaker sounds??? So then why do the "better amps" try to achieve higher slew rates, resulting in "squarer" square waves?  In fact, by your terms, why bother to even measure it?

https://www.audioholics.com/audio-amplifier/amplifier-slew-rate

The whole article flawed because it is based solely on the use of sine waves.  I don't know about you, but I listen to more than sine waves (and possibly flutes).

But square waves, sawtooth waves, and complex waves have "verticle" (i.e., instantaneous) rise times and this is where slew rate would come into play.

If you look into this a bit further you will discover that these other waves are combinations of sine waves, and there are no musical signals which have an instantaneous rise time. If you put any musical signal through a spectrum analyzer you will see it broken down into these various frequencies.

https://mathworld.wolfram.com/FourierSeries.html

As the article you dismiss states, once the slew rate of the amplifier is high enough that it can amplify the highest required frequencies without distorting them (it is not slew rate limited) then a higher slew rate does not matter.

I’ll leave it to you to dig in and educate yourself about this, since instead of trying to understand slew rate, it appears you are only interested in proving you were right despite the fact what you initially stated is undeniably incorrect.

I’m done with it. Good luck in your journey.

But to "composite" a square wave from sine waves would take sine waves way up into the ultrasonics and where would that put the slew factor???

A Hammond uses exactly the technique to which you allude. But it never achieves anywhere near a true square wave.

Actually, one could make the argument that a sine wave is just a bunch of square waves with short duty factors and their amplitudes arranged in a "wave" pattern. But again, how many would it take to achieve the true sine pattern?

No musical signals with an instantaneous rise time?

If you play a square wave and the amplifier produces 17v/ms and the speaker needs 17 volts to reach the desired volume, it can occur in no less than 1 ms.

If the other speaker is 10 dB more efficient it only needs 5.4 volts to play the same volume so it can occur in no less than 0.32ms.  That's the math.  Whether the speakers can actually keep up is another matter/discussion.

Regarding being right... it seems that you read one thing and think it applies to all cases..., and obviously it, and therefore you, must be right. Show us something where slew factor is discussed in relation to other wave forms as they actually exist. You are only presenting one side of the argument.

Herman = +150

Toddalin = -165

There is a difference between sensitivity and efficiency.

Sensitivity vs. Efficiency see below page one paragraph C:

Mike

https://www.lansingheritage.org/html/jbl/reference/notes/tech1-3a.htm

Is not the concern the perception of sound that is being produced the factor that determines how one chooses a Speaker.

Speaker Design will require a certain downstream electronic support to enable them to function something like the design intended.

As the Speaker in use in the home or new listening space, the speaker as a result, is no longer in the room or allocated space used to produce the design.

When the speaker is in use in the home it is already compromised, as it is no longer functioning as per the design did when in the space used during its creation.

What matters next is how the Speaker delivers sound, is it Voluminous or Confined, is the Sound presented with Speed or laid back as a delivery, is colouration perceived as being present and being an influence on how the quality of sound is perceived.

How a Speaker is driven does not have too much influence on these attractive traits, it is the downstream devices that manage the transfer of the signal to the final manager of the signal being the Xover, prior to electrical signal being converted into mechanical energy and hence sound being produced.

If the signal is deficient, the Speaker can not add the data that is missing.

Speakers are most liked when the Speaker is capable to produce the perception of the following as the extracted data from the recording:

Dynamics - Micro Details - Attack - Tone - Timbre - Envelope and Coherence - are what really wins ones full admiration and attraction when experienced being delivered.

Such a perception of these traits presence will be much more aligned with the quality of the generated and transferred signal from source to Xover, and not the means used to create the required AC Current necessary to drive the speaker. 

I own very large efficient speakers (102db) and although they can easily be powered by a tube push-pull amp tube amp (10 watts per channel) to reasonable and higher levels they still sound really good with the bigger more powerful ss amps. The point is if you buy efficient speakers you are opening up all doors to amps of different power output.

@phd 

At 102db efficiency may I suggest you try SETs rather than push pulls? You might be in for a big surprise. A classic 300b amp will amply drive those speakers unless they have a weird impedance pattern

antigruge2, that is very interesting recommendation about trying a set amp. This has been recommended before and I look forward into to getting one to try in the near future.

This sounds like Wilson Audio, which I have.  Do not assume everything you read.  I recently auditioned a pair of Alexia 1 that are supposed to require lots of SS power.  The sounded better and more musical at the same output with an Audio Research 75SE than they did with a McIntosh 450wpc SS amp.  

The speakers I was referring to were not Wilson's. Nonetheless, it is interesting what you posted about Alexia 1's. They are known to be extremely difficult to drive. Is it possible that the ARC Ref 75SE has a more capable transformer, and as such can drive the Alexia's? 

Interesting discussions on efficient speakers...  I have run through the gambit of lower efficiency 87db-89db speakers and efficient 94db and very efficient 103db - 106db.  And I've also gone through the same regarding the amps I believed needed to drive them.  After my experiences over the past 20+ years, I moved toward the higher efficiency types (94db - 106db) with low-wattage (flea-watt) class-A single-ended both tube and solid-state amplifiers.  As I moved from lower efficient to higher efficient speakers keeping my higher-powered amps in play, I could tell the difference in micro-detail.  Going then from the higher-powered amps to the flea-watt amps, there was a slight but noticeable improvement in micro-detail, with no loss of dynamics or bass response at my normal listening levels.  Those speakers by the way had impedances between 6-ohms and 8-ohms nominal and all had multiple drives/crossovers.  Presently, I'm using a single-driver speaker with of course no crossover, that is 106db efficient with a 12.9-ohm (resistive) impedance.  Every one of my flea-watt amplifiers can drive these speakers to uncomfortable listening levels with absolutely no loss of any dynamics.  However, I would expect that at a 106-db efficiency, and at the rather high 12.9-ohm resistance.  Even my 94-db speakers were driven with the same flea-watt amps with no dynamic compression at comfortable listening levels.  I have not heard a variety of lower efficiency/impedance speakers, however in every case with the speakers I've had, the more efficient the speaker, the greater micro-detail I've heard.  The only other lower efficiency speakers I've heard equivalent or better micro-dynamics, especially in the upper mid/tweeter frequencies are planar speakers.  Perhaps that has more to do with the lower moving-mass of the planar electrostatics than the efficiency.  Finally, one of the tests for me was the low, no-signal noise from the electronics through the speakers.  If you can hear that slight noise with very efficient speakers versus lower efficient speakers, what micro-detail would you then be missing in the music with those lower-efficient speakers ?  Your individual experiences may vary.  This is just what I've seen/heard over the years...  

@dhite71

+1

There has been this old adage of tube watts being more powerful than solid state watts. For most of the last fifty years I used mammoth high powered solid state amps. Then about five years ago switched to Audio Research Reference amps 160m monoblocks and 160s. I run the 160s in triode mode… so only 70wpc and they are ferociously relaxed and powerful, absolutely no lack of muscle… but they don’t flaunt it… it is just there, rock solid at any volume.

I also have a friend with a pair of Wilson Puppies and an Audio Research VT80. They drive the Wilson’s to incredible loudness without any sign of running out of power or dynamics, rock solid. I really cranked them last weekend.

While I haven’t recently tried to put 70wpc tube power up against solid state but I am pretty sure it will stand up against two or more times the SS watts. So, I had figured the old adage of the difference between tune and SS was really subtle. It isn’t and still seems to be there..

Ok I have Polk lsim707 ,88 db and thery are driven with a Caryin XL 55 tube amp light 20 wpc and they sound great....there in a very large room with cathedral ceilings....i was,told owe you can't drive them with that tube amp....you need 300 wpc.....well they were wrong ,totally. I have used these hook up for 2 years.....no problems at all....

I think many of the values discussed here and elsewhere assigned to high efficiency speakers are not accurate. First the entire discussion of what is delivering the improved efficiency is not differentiated- is it drivers or how the driver is used that gets you better efficiency? These two ideas.make a huge difference in performance but are distinctly different methods of achieving improved efficiency with their own costs, benefits and penalties..

Example 1: a lower efficient driver can be made more efficient by placing it on a horn, which complete changes other characteristics/parameters of performance and behavior. An acoustic suspension system or a horn system are very different from each other in many ways having a direct impact on performance.

Example 2: You can build a more efficient driver by lowering the mass of its moving parts. Lowering this mass can cause multiple things to happen, typically increasing ring modes and distortion. Here efficency makes the driver sound worse. Another outcome of lowered mass is poorer low frequency performance.

Example 3 Higher efficiency drivers do not always offer lower power compression. If you use titanium instead of aluminum for your former, the thermal resistance is far higher with titanum than aluminum, so heat can’t escape the lower mass system increasing thermal power compression. Higher efficiency increases thermal power compression in this case. DO you know what your VC former material in the speaker system you buy actually is? Thermal power compression is affected by a long list of factors that are far too detailed and complex to discuss here or ina spec sheet: issues such as VC impendance, VC material, front plate/pole piece proximity to coil, airflow and venting of the magnet system. Looking at a efficiency measurement and assessing quality is like looking at frequency response and assessing sound quality- it really isn’t an indicator of performance in a way that is simple or easy to [universally] understand.

I know poeple really want there to be a simple way of looking at things but this is some deep science. A speaker involves practicaly all the sciences and there is no way to simplfiy it and express that in a spec- unless you are willing to bullshit or tell a helluva convincing marketing story. Most do exactly that, but its a diservice to the thinking person’s aims in a playback system.

If you love the idea of a flea watt amp, you are sorta stuck with high efficiency loudspeakers to have any hope of dynamic range. If you are more open minded and are wiling to look at moderate efficiency speakers in the mid 80s, using the wide array of excellent high power amplifiers available, or active speaker configurations, you can have your low distortion, wide dynamic range AND better bass AND wider dispersion, etc, etc. But you cannot have all that AND super high efficiency.

I think we are back to listening to a speaker with a proposed amplifer and assessing if this combination works for you and addresses the things you care about.

Brad

.

You can also make a more efficient speaker by "tightening up the tolerances" (i.e., tighter fitting voice coil/gap) and increasing the number of windings within the same area (e.g., using flat-wound wire), without causing other problems.

BTW, a lighter cone will also allow the driver to play to a higher frequency without break-up.

My "Merman" speakers are extremely efficient, and sensitive, without horns, and can easily do "live concert levels" and I wouldn’t have it any other way.

Remember that the volume control is nothing more than a "focus knob" and sometimes you really need that volume to bring the cut into focus.

Also, I feel that an "immersive experience" takes realistic volumes to achieve.  You can't immerse yourself in a tub of water if it only covers your toes. 

If you want/like 8 ohm 86 dB sensitivity speakers you will most likely have to go with a high watt output solid state amp (>150 watts). 

It takes 150 wpc plus (ss) to drive a speaker rated at 86 db?

75 Watts is fine for 86dB speakers. (Dynaudio) Just my experience

If you want the peaks to be at realistic levels, yeah, 150 watts is probably about right to get you to about 107 dB or maybe only a bit over 100 dB when you consider thermal compression.

Heat Dissipation and Power Compression in Loudspeakers:

@lonemountain wrote:

... If you are more open minded and are wiling to look at moderate efficiency speakers in the mid 80s, using the wide array of excellent high power amplifiers available, or active speaker configurations, you can have your low distortion, wide dynamic range AND better bass AND wider dispersion, etc, etc. But you cannot have all that AND super high efficiency.

Sorry, but the above makes little sense to me. 

If by "mid 80s" you mean sensitivity in dB's, then it's a very low efficiency design (i.e.: ~0.2%) and not "moderate" by any means. 105dB's sensitivity on the other hand translates to 20% efficiency, which is very efficient. 

Contrary to your views I find efficient speaker designs - say, from 95-100dB's on up - to be the best way to achieve the combination of low distortion, wide dynamic range AND better bass, with the proviso that the latter requires large size to achieve a fairly deep extension, but that's not a design deficit nor a sonic impediment. And, if I'm to understand you correct, wide dispersion isn't a trait, but a characteristic; if anything a narrow and fairly uniform dispersive nature has advantages over a wide and likely uneven ditto. 

Finally, high efficiency speaker designs can as well and advantageously be run actively. In fact I find that's where they really shine.

Problem is that they also require a very large ss amp upstream to drive them. Something that can push a lot of current, which pretty much rules out most low-mid ( maybe even high) powered tube amps. When I mentioned this to the person doing the demo, i was basically belittled, as he felt that the efficiency of a speaker is pretty much irrelevant ( well he would, as he is trying to sell these speakers). The speaker line is fairly well known to drop down to a very low impedance level in the bass regions. This requires an amp that is going to be $$$, as it has to not be bothered by the lowest impedances.

Low impedance and low efficiency is a bad combination if you want the best out of your amplifier, regardless of the amplifier type.

@ditusa has put his finger on a serious problem with lower efficiency speakers, one that isn't overcome by higher amplifier power, in fact makes it worse.

But you also have the problem of distortion from the amp. With any amplifier, the harder it has to work the more distortion it will make. So 4 Ohm distortion is always going to be higher than 8 Ohm distortion. You might think that small increase isn't audible but that would be ignoring how the ear perceives sound and in particular, tone color and sound pressure.

Sound pressure is perceived through the higher ordered harmonics, If you increase them by even tiny amounts its audible as greater loudness (BTW this is easy to demonstrate through simple test equipment).

Distortion modifies the tone color of instruments by adding harmonics. IOW the ear perceives harmonics as a tonality. So adding even a slight amount of distortion will color the sound and very likely in the direction of 'harsher' and 'brighter'.

Put yet another way, if a speaker could be made to be 8 Ohms instead of 4 without changing anything else, the perception would be that the speaker became smoother and more detailed simply because any amplifier driving it would have less distortion.

So efficiency and impedance are both important!!

@phusis

I normally agree with your posts, but not this one. A transducer engineer like Doug Button (he worked at EV when I did, and then again at JBL when I was there) or Rich at ATC would agree with my post (maybe not exactly the way I say it). The physics of the speaker is a balancing act: if you want more efficiency you give up other advantages. Im not saying this is wrong, it’s simply a choice. A moderate efficiency speaker (86dB 1w/1m) is not a mistake either as it is just a different choice that enables other performance features that high efficiency cannot offer. You cannot have it all. My point is simply that this thread seems to universally promote that high efficiency is the primary hallmark of high performance and that is simply not true. It can be important if you need High SPL, or like horns or big wave-guides (which can image well), or use speakers in a highly reverberant environment where narrow dispersion is an advantage, but these conditions certainly don’t exist in every room or for every listener. It’s a trade off and is not a "good or bad" or "right and wrong" thing. Decide what you want, then figure out what speakers do that.

A good example of deciding what’s important to you is a listener in a small space; a small stand mount speaker with excellent low frequency output, say a LS3/5a type KEF design would be a good choice. Super high efficiency is not gonna happen in this type of design. If a listener wants wide dispersion speaker because he/she wants it to sound the same anywhere in front of the speaker, super high efficiency is not gonna happen. If a listener wants super low distortion because they are in mastering or recording, then super high efficiency is typically not a goal. The hardest part may be understanding what you want in your space vs what other people want in their space, as the reviews say this is good or bad but don’t really discuss the space or the listeners goals much. Whether it’s good or bad is ALL about matching your space and your goals with a speaker. High end speakers are not good or bad on some universal scale. There are too many engineering goals/design features to account for that define good or bad in a given space. Efficiency is just one of these many features.

Brad

@atmasphere   Thank you. If you would have told the dealer exactly what you posted, he would have belittled you just the same. Some folk have agendas, and in this case, the guy was only interested in selling this speaker....not in discussing in any way the potential downfalls that this design elicits. OTOH, that was his job that day.

@lonemountain I couldn't agree with you more, it is absolutely important that one match their desired speaker to the space/room that it is going to be listened to in. However, the efficiency and the very nasty load that the speaker in question presents to the amp is a factor that IMO should not be overlooked, regardless of the room size. Personally, i am not that concerned about speakers that present a moderate efficiency, only those ( like the design in question, and others) that present basically a short to the upstream amp! 

@lonemountain +1.

Dear @daveyf  : IN any case and not so expensive you can find out the  Parasound JC 1+ monoblocks that when you listen it in any speaker at any SPL you did not ask if you are listening tube or SS amp but only enjoying MUSIC.

John Curl is a very low profile Master Designer Electronics Engineer.

Parasound Halo JC 1+ monoblock power amplifier | Stereophile.com

Regards and enjoy the MUSIC NOT DISTORTIONS,

@rauliruegas Funny you bring up the Parasound amps. A fellow a'phile whom I know well, decided to buy a pair of very expensive and very difficult to drive speakers, reasoning like you, that the Parasounds would be the answer. His budget was limited a little, so he spent the $$ on the speakers and left himself with only one option for the amps...based on his budget. Let's just say that the speakers went onto the used market within a few months, and he was forced to sell them at a considerable loss. I believe what @atmasphere noted above is the whole reason.

PS. He no longer owns the Parasounds either.

@atmasphere +1 I couldn't agree more!

Mike

The physics of the speaker is a balancing act: if you want more efficiency you give up other advantages. Im not saying this is wrong, it’s simply a choice. A moderate efficiency speaker (86dB 1w/1m) is not a mistake either as it is just a different choice that enables other performance features that high efficiency cannot offer. You cannot have it all.

@lonemountain Unless you can. I have a set of Classic Audio Loudspeakers (model T-3.3) which are some of the most revealing speakers I've heard, even compared to the best ESLs. They are flat to 20Hz, are 98dB, field coil powered and 16 Ohms. So fast, revealing, full bandwidth and actually work quite nicely in a smaller room since you can back them up against the wall behind them without making them boomy or losing any sound stage palpability. Put another way I don't know of a speaker at any price that works better, although its probably out there. 

They are not cheap; IMO your comment would be more accurate if price were part of the equation.

@lonemountain --

The question is, certainly to me, what we’re actually disagreeing on here. My remarks above were aimed specifically at the parameters brought up by you, namely distortion, dynamic range and "better bass," and I’ll maintain that higher efficiency is the preferred route for these parameters to be better realized. While many understand high efficiency to be mainly about achieving higher SPL’s, to me it’s about what these designs offer sonically as a consequence of their higher eff., and that it translates at moderate SPL’s as well.

Decide what you want, then figure out what speakers do that.

To me it’s really the other way ’round; observation and discovery (and this is where open mindedness is truly challenged) ultimately points me in a direction of speakers and overall implementation, stuff I could hardly imagine or have come by if it weren’t for experimentation or even chance. It’s a process where preconceptions are readily confronted.

As to my clarification on efficiency, it exposes how many audiophiles tend to exaggerate the efficiency of speakers with a sensitivity range somewhere between the typical 80-90dB’s. Why, or how is that relevant? Because as poster @atmasphere and ​​​​@ditusa point to you don’t just compensate freely for low efficiency with more power, not even in a home setting, and this goes for both speakers and amps.

Efficiency is just one of these many features.

Sure, but for my own part I’ve never claimed it’s the only important aspect (though a vital one). Rather it often comes down to defending high efficiency in the face of the opposing view that low eff. designs can avoid the limitations of poor efficiency simply by adding more power, and thus, implicitly, are having the "fuller package" by comparison. I absolutely disagree with that.

@atmasphere wrote:

Unless you can. I have a set of Classic Audio Loudspeakers (model T-3.3) which are some of the most revealing speakers I’ve heard, even compared to the best ESLs. They are flat to 20Hz, are 98dB, field coil powered and 16 Ohms. So fast, revealing, full bandwidth and actually work quite nicely in a smaller room since you can back them up against the wall behind them without making them boomy or losing any sound stage palpability. Put another way I don’t know of a speaker at any price that works better, although its probably out there.

They are not cheap; IMO your comment would be more accurate if price were part of the equation.

I’d add it’s not limited by price as much as mere physics and overall execution/implementation.

@phusis

Nicely written! I enjoy your perspective. When you say that efficiency is not the most important aspect of performance, you and I are on the same page. I disagree that efficiency is the "preferred route" in achieving lower distortion, improved dynamics or increased bass. There are so many other avenues to these features.

I did not say that low eff. designs avoid the limitations of poor efficiency simply by adding more power. There may not be limitations of lower efficiency designs, depending on your goals. Or there could be limitations of a high efficiency design. I think the whole array of solutions are far more complex than high or low efficiency "spec" on a spec sheet. Whether something is 92dB 1w/1m in a loudspeaker gives you zero information about quality when compared to a 86dB 1w/1m spec.. You only know the designer chose to chase efficiency (probably for more than one reason). Intended application is everything..

Some lower efficiency designs can achieve lower distortion in the driver, or can extend low frequency of that driver or both. Or your lower effieciency design may improve cooling and power handling without extending voice coil length. I guess to me its like horsepower tells you zero about the performance of a car. There are so many different options available to a skilled designer that focusing only on a high efficiency design is not wise, again, depending on your goals. I favor lower distortion myself, I want to hear more of the fine details, the reverb tails, the room sound, etc. If I can have lower distortion that reveals more of that fine detail in exchange for a larger power amp, I’m in.  That's the trade off I am talking about.  And I'll stick to my guns on this one, you cannot have it all.  

Brad

.

Dear @daveyf : The issue thatan amplifier working harder develops higher distortions could not be exactly as was posted.

You can read in the link that the JC 1+ gives you at full power output same distortion levels at 8ohm, 4ohm and 2ohms: 0.15%.

The other issue about is that the levl of distortions each one of us can detect it as an added colorations depends on what the brain amygdala whole audio/MUSIC information is hang on to for the life experiences of different kind of sound and different kind of SPLs.

J.Curl knows exactly how design  "  a huge ss amp upstream ".

Speaker efficiency always is important depending how you paired with the rigth amp in the rigth room and of course inside your MUSIC reproduction priorities or restrictions. 

Now and is something that you don't touched yet other than " good sounding " and you did not tell us with wich electronics ( overall ) you were listened, with which MUSIC sources and MUSIC gender and at which SPLs.

R.

Noise/distortion --> the room and the speakers trump whatever anyone’s attributing to any decent amp.

It’s like you’re having your carriage pulled by a dying horse, but you’re dead focused on greasing the wheels with some special oil secreted on a blue moon night.

@rauliruegas I cannot comment too much on the sound of the Parasounds and the speaker at this fellow’s room. I heard the combo briefly, but do remember thinking that the synergy was not there between the components.

Keeping in mind that the speakers in question drop down to around 1ohm in the bass, resulting in a speaker that very few amps can drive to anything that can bring about their best. Nonetheless, the Parasounds were not an amp that resulted in this fellow being impressed with the combo.

Keeping in mind that the speakers in question drop down to around 1ohm in the bass, resulting in a speaker that very few amps can drive to anything that can bring about their best. 

Any speaker that drops to 1 ohm was designed by a lazy low IQ individual. Such a speaker (his low IQ legacy) should be torn down and thrown in the garbage can.

@deep_333 LOL, there are a number of well respected speakers that drop down to 1ohm. I won’t consider them for purchase; but I suspect that most folks will not label their designers...’lazy low IQ individuals’! The speakers I was listening to in my OP come from a well known designer who has had several ’amp busting’ speakers on the market in the past.

Dear @daveyf  : About the JC 1+ I was refering to the speakers in demo by the seller in your OP and not about the owner of those Parasound amps that btw can handled with out problem to high SPL that 1 ohm impedance.

R.