Something I've never understood about Klipsch speaker specs

[Cope]

Feel free to boot this to the Beginners section if it's too dumb a question... 

 

So, take your typical Klipsch bookshelf speaker. Continuous power handling is somewhere around 100w, and Klipsch say  to get an amp that can supply something roughly equal to that.

 

Thing is, sensitivity is 96dB, so when would you ever need 100w? How far away from your speakers do Klipsch think we are sitting? Or is this some headroom thing to do with the woofer? I heard the speakers linked above in a store recently, and they certainly sounded like they needed more something than the amp was providing.

 

But then, there are all these folk powering Klipsch with teeny valve amps.

 

It confuses me.

[Primare Knob]

I don't know much about the speakers, but usually the Wattage ratings of the speaker are how much heat it can handle, or in other words the hetat the voltage and amps produce runnings through the speaker at 100W.

Whether or not you need a 100W depends indeed on efficiency and listen distance.

Whether a small or a big amp can drive the speakers well has more to do with the design of the amp than with the output power.

[Cope]

@Primare Knob Hmm, so maybe, by that logic, Klipsch isn't so much saying "you need 100w for these speakers", but rather "the more headroom the better, and 100w is how much you can put through these without issue"?

[Primare Knob]

I would not do that. You can do the calculations yourself for a100W with 96dB efficiency. Even with 1W at 3 meter, it still might be to much.

There is a possible reason why people go for a tiny amp with high efficiency speakers. You are only using a very small output and most big amps aren't very good at producing small signals. A tiny amp will be pushed a little harder which could produce a better result.

But there is always an interaction between amp and speaker as the impedance chances the demand on the amp chances. This is where a good design can outperform better specifications.

[Cope]

Oh, I agree it would be ridiculous. 100w with that speaker would be 115dB, and its 400w peak would be over 121dB. Insanity.

 

I take what you mean about a better design with low output focusing on better production of listening level volume (is that First Watt's whole thing?), but then my question remains - why are Klipsch saying you should have a 100w amp?

 

Whenever I ask the question "do you need a big or small amp to power Klipsch?" the answer always seems to be "yes".

Edited November 26, 2018 by twofires

[Ittaku]

9 minutes ago, twofires said:

Oh, I agree it would be ridiculous. 100w with that speaker would be 115dB, and its 400w peak would be over 121dB. Insanity.

 

I take what you mean about a better design with low output focusing on better production of listening level volume (is that First Watt's whole thing?), but then my question remains - why are Klipsch saying you should have a 100w amp?

Maybe they are actually appealing to the market that wants 120dB transients...

[Cope]

40 minutes ago, Ittaku said:

Maybe they are actually appealing to the market that wants 120dB transients...

Claps as loud as thunder claps.

[Guest thathifiguy]

IME the "wattage rating" of speakers is virtually insignificant, unless they are active speakers.

[crisis]

15 hours ago, twofires said:

@Primare Knob Hmm, so maybe, by that logic, Klipsch isn't so much saying "you need 100w for these speakers", but rather "the more headroom the better, and 100w is how much you can put through these without issue"?

This

14 hours ago, Primare Knob said:

I would not do that. You can do the calculations yourself for a100W with 96dB efficiency. Even with 1W at 3 meter, it still might be to much.

There is a possible reason why people go for a tiny amp with high efficiency speakers. You are only using a very small output and most big amps aren't very good at producing small signals. A tiny amp will be pushed a little harder which could produce a better result.

But there is always an interaction between amp and speaker as the impedance chances the demand on the amp chances. This is where a good design can outperform better specifications.

No. Headroom is everything. Look at the distortion measurements of your amp and see where they are measured. You will rarely be using 100w of a 100w amp unless you are driving to destruction. It will be used for very short peaks at best. "Pushing" an under powered amp harder is a recipe for disaster.

[Cope]

21 minutes ago, crisis said:

No. Headroom is everything. Look at the distortion measurements of your amp and see where they are measured. You will rarely be using 100w of a 100w amp unless you are driving to destruction. It will be used for very short peaks at best. "Pushing" an under powered amp harder is a recipe for disaster.

Look, I agree. I replaced a "100wpc" Marantz receiver with a 200wpc Rotel integrated that can put out around 400wpc at 4 ohms in order to drive my KEF Q700s properly. I definitely notice a difference.

 

Having said that, driving a valve amp towards the limit is a different thing to solid state, although the reasoning is beyond me. Or, I haven't bothered to google it yet. 

 

But anyway, you'd attribute the reasoning for Klipsch's recommendation to headroom, assuming a solid state amp?

[Primare Knob]

No. Headroom is everything. Look at the distortion measurements of your amp and see where they are measured. You will rarely be using 100w of a 100w amp unless you are driving to destruction. It will be used for very short peaks at best. "Pushing" an under powered amp harder is a recipe for disaster.

No one is talking about an underpowered amp, that is your interpretation. Even a small amp can deliver large peaks if well designed. A small output signal on a powerfull amp can be just as difficult, and nobody is measuring that.

First you need to understand what headroom is for. There is no point in buying into big wattage if you never use 80% of it. It's better money spend on a well designed amp that can deliver the full experience.

It's all about dynamic range and speaker impedance interaction.

[crisis]

6 minutes ago, Primare Knob said:

No one is talking about an underpowered amp, that is your interpretation.

Its my interpretation of this - " A tiny amp will be pushed a little harder which could produce a better result. "

 

6 minutes ago, Primare Knob said:

 

 

Even a small amp can deliver large peaks if well designed.

Small as in power?

6 minutes ago, Primare Knob said:

 

A small output signal on a powerfull amp can be just as difficult, and nobody is measuring that.

Don't understand but yes, nobody is measuring that.

6 minutes ago, Primare Knob said:

First you need to understand what headroom is for. There is no point in buying into big wattage if you never use 80% of it. It's better money spend on a well designed amp that can deliver the full experience.

Try this. It helps.

https://www.crownaudio.com/how-much-amplifier-power

 

6 minutes ago, Primare Knob said:

It's all about dynamic range

"Headroom" provides for the delivery of un-distorted wide dynamic range. The ability to deliver a few watts on idle (the majority of material) and large peaks in louder sections (ie deep bass or crescendos).

 

6 minutes ago, Primare Knob said:

 

and speaker impedance interaction.

Whatever the impedance the more headroom, the louder music peaks will be reproduced with minimized distortion or clipping.

[Cope]

5 minutes ago, Primare Knob said:

There is no point in buying into big wattage if you never use 80% of it.

Okay, so return to the main question here, Klipsch are implying that you will use 100 watts when using these speakers, because... they have a wide dynamic range? Easy to drive, but hard to fully experience?

 

I take it by good quality in lower wattage amps you're talking about what happens when the impedence drops? For example, if you need 100w for peaks when the speaker impedance drops to 4 ohms, a good 50w @ 8 ohms amp will do that where a crappy 80w amp may not? Or am I on the wrong track?

[Primare Knob]

First of all dynamic range is dictated by the source material, the speaker and the amp simple have to follow the peaks and quiet parts based upon your volume settings. With music there is no reference as with movies, but the average dynamic range of music hovers around 40dB. Let's say for example the average output is based upon 85dB as with movies, than your peak output will 105dB max.

A speaker with a 96dB with 1W sensitivity at one meter will need 3 times more power to produce 105dB max peak, which comes down to 8W, keep doubling that for every meter more than 1, that you are sitting away. On average you will end up around 32W based upon a 3M distance. With a 100W amp you will have roughly 5dB of amplifier headroom.

No there is the debate that most amp can deliver +3dB at peak without a problem as peaks are only short outburst. Then there is in room gain that can boost your output and then there is the variable as at what levels you are listening.

I have a calibrated HT setup but never listen at the calibrated level of 85dB, as I find it simply to loud. I listen at -12.5dBFS and my peak output is only 92.5dB which would require less than 4W at peak output at 3M distance. The more I control my room with acoustics the more these louder levels become easier to listen to.

The only reason I can think of is that the speakers might produce a difficult impedance or phase load that Klippisch is talking about the need of a 100W, but when so, they have a funny way of saying this. They could possibly just be thinking that most 100W amps are stable enough to drive the (difficult) speaker load at average listen levels.

I use Martin Logan's speakers where the impedance dips to 0.6 Ohm. Many people use these speakers with cheap amps, AVR's or unrated below 4ohm without a problem. At small signal levels that might probably be fine and protection circuitry kicks in when needed, but at movie peak outputs of 105dB at less than 1-2 Ohm that might be a different story.

Have you asked Klippisch themself about the reasoning behind this? From a technical point of view it doesn't seem to make a lot of sense.

[Cope]

@Primare Knob I haven't yet asked, no, but you've more or less clearly articulated my vague gut feeling about the whole thing. It doesn't make a lot of sense, unless "power" is being used as a heuristic for stability/quality so they don't have to get into conversations with customers (and manufacturers) about which amps are quality ones.

[Primare Knob]

Looking at it from a manufacturer point of view.

People buy my speakers and keep asking what amplifier to use. I as a manufacturer cannot recommend A or B so I'll give them a guide line. It's less risky to recommend a big amp than a small amp, and to make things easy I'll let them match it up to the ratings of my speaker, as they most likely know that most people never will come close to max output levels of the speaker as it will damage your hearing. Even when the speakers break on the occasional idiot, we can simply tell him that he's overdoing it as there is no way in telling when a volume control is actually outputting its max at which setting. Most will do this before their max.

If you read between the lines, all they are saying is that it can be risky using a smaller amp. And this is advice given to anyone that is reading it, including a lot of people that don't know anything.

[davewantsmoore]

23 hours ago, twofires said:

Feel free to boot this to the Beginners section if it's too dumb a question... 

 

So, take your typical Klipsch bookshelf speaker. Continuous power handling is somewhere around 100w, and Klipsch say  to get an amp that can supply something roughly equal to that.

 

Thing is, sensitivity is 96dB, so when would you ever need 100w? How far away from your speakers do Klipsch think we are sitting? Or is this some headroom thing to do with the woofer? I heard the speakers linked above in a store recently, and they certainly sounded like they needed more something than the amp was providing.

 

But then, there are all these folk powering Klipsch with teeny valve amps.

 

It confuses me.

 

If we assume that the 96dB figure is for 1w input power @ 1m distance from the speaker .....  and assume that we're listening 4m away .... this shows us a "worst ish case scenario"

 

96dB/w/1m

90dB/w/2m

84dB/w/4m

 

1w = 84dB

2w = 87

4 = 90

8 = 93

16 = 96

32 = 99

64 = 102

 

128 watts  = 105dB @ 4m

 

Seems about right.  The speaker can reach "reference level", which is 105dB per channel in the listening position at around it's full power rating.

 

Most sane people would only want 105dB to be an extremely short peak, ie. the loudest microsecond of a "whack" or a "bang".

 

 

 

[Addicted to music]

51 minutes ago, davewantsmoore said:

 

Seems about right.  The speaker can reach "reference level", which is 105dB per channel in the listening position at around it's full power rating.

 

Most sane people would only want 105dB to be an extremely short peak, ie. the loudest microsecond of a "whack" or a "bang".

Well then I gather I don’t fit in the “most sane people” category.....

 

screw the figures and formulae I say, the louder the better....and the more watts the merryer.  Even better if it’s super clear and distortion free!  And if you can feel it thumping your chest and moving the hair on your neck....not that’s a bonus!   

[davewantsmoore]

14 minutes ago, Addicted to music said:

Well then I gather I don’t fit in the “most sane people” category.....

Yes, I think that's pretty clear....   Heh, Just kidding.

 

I doubt you listen a lot higher than 'reference', unless you have very dynamic content (so the average levels are a lot lower than the peaks).

[Addicted to music]

15 hours ago, davewantsmoore said:

Yes, I think that's pretty clear....   Heh, Just kidding.

 

I doubt you listen a lot higher than 'reference', unless you have very dynamic content (so the average levels are a lot lower than the peaks).

Oh Dave,

 

doesnt matter what content, when no one is home, the volume goes up,  it puts a nice smiley happy grin on my face and my toe starts tapping and hands play air guitar......    I can now go louder now without that vibration cause I used those vibration pads from Bunnings....nice!   

[Neilsy]

Bear in mind hear, when a manufacturer says 97dB or 99dB 1w 1metre that is often an easy load frequency... Such as 1kHz as a pure sine wave.

A piece of music or sound effect ofcourse has a blend of many frequencies in the spectrum, some which consume many, many times the watts such as low frequencies.

Consider this, for example, (correct me if wrong as I'm going by memory) for every 3dB you are to add to a sound through the likes of equalisation (such as boosting a bass frequency), which the ear perceives roughly twice as loud, it takes 6x the watts. Yes, six times.

So if you had a sound effect in your theatre at 120hz already burning up 40w of power for that explosion or drum hit, whatever, and you are doing any EQ of say 3dB more along that area (like a bass tone shelf) then that 40w can now consume up to 6x that amount.

So this is where in the pro audio world massive amounts of amplification is everything, because we're often tweaking EQ to taste.

But the theory applies at home too.

That's why in cinema most EQ tweaks are very, very minimal and speakers with high efficiency are everything because a cinema chain is looking for low cost amplifier outlay.

[Cope]

It's interesting - today, I was demoing some integrated amps for my work-in-progress second system. In the room with these amps were the following speakers:

 

Klipsch RP-600M

KEF R3

KEF LS50

SVS Ultra

and a few other things I didn't bother to listen to with the amps in question. 

 

Now, the R3s were the best thing in the room by a considerable margin, and considering the price jump that isn't surprising. But if I had to pick a second place, it'd be the Klipsch. And that's a very different experience to the one I had with the same Klipsch speakers at a different store a week ago.

 

The difference? A week ago I heard them powered by a 50wpc Class D Pioneer, and today I heard them in front of two hefty Class AB units - a Rotel RA-1572, and a Marantz PM8006.

 

Whatever the sensitivity, the Klipsch like a good bit of welly.

 

Side note: the Marantz was the winner, to the extent the third amp on the list (a Yamaha A-S1100) didn't even get a look in.

Edited December 1, 2018 by twofires

[davewantsmoore]

On 28/11/2018 at 8:35 PM, Neilsy said:

Consider this, for example, (correct me if wrong as I'm going by memory) for every 3dB you are to add to a sound through the likes of equalisation (such as boosting a bass frequency), which the ear perceives roughly twice as loud, it takes 6x the watts. Yes, six times.

+3dB = 2x watts

On 28/11/2018 at 8:35 PM, Neilsy said:

because a cinema chain is looking for low cost amplifier outlay.

 

 

Usually...  it is more so that without very high efficiency .... even if you used the most powerful amplifiers (cost be damned) that the speaker can handle .... you will never make enough SPL at large distance.

 

 

 

Example.    A hifi speaker of 90dB/w @ 1m .... is only 66dB/w @ 16 meters

 

.... If you want to make 105dB at the listener (cinema reference level) .... then the hifi speaker would in theory need 16,000 (!!!) watts to do that @ 16m     If the hifi speaker could take 1,000 watts (it probably can't) .... it would only make 94dB @ 16m  Pathetic.

 

A high efficiency speaker might be 100dB/w @ 1m .... and this is 76dB/w @ 16m.    It will make the 105dB @ 16 meters, with about 700 watts.

[blakey72]

Klipsch can either be very good or very bad. There's only one amp difference between the two.

[jamiebosco]

I think Klipsch's recommended amp rating of 100w makes more sense when you consider their actual sensitivity may be something closer to 91 - 93dB, instead of the 96dB listed in their spec sheets. Being 3-5dB off may not sound like much (no pun intended) but this would be the difference between thinking you're cruising along using 20-30w of amp power, when in reality you're using 60-100w.

 

I've seen it mentioned several times on AVS, Audioholics and diyAudio about Klipsch's sensitivity ratings being inflated by a few dB, though this is usually in regard to their Synergy and Reference product lines and not the Heritage,Cinema or Pro lines.

I have often read about "Hoffman's Iron Laws" and some of Klipsch's product specs definitely seem to be (at the very least) bending these laws - small to medium sized bookshelf speakers with a single 6.5" woofer, metal dome tweeter, 45hz extension and 96dB sensitivity? seems almost too good to be true?

 

https://www.avsforum.com/forum/89-speakers/2128818-can-klipsch-speaker-actually-meet-s-specs-no-can-t.html

https://www.diyaudio.com/forums/multi-way/110418-klipsch-efficiency.html

https://www.avsforum.com/forum/89-speakers/2012897-klipsch-rp-280f-tower-speakers-official-avs-forum-review-2.html#post34544729

 

 

Quote

Quote:

Originally Posted by adam2434

This is only one example of how a Klipsch floorstander sensitivity compares to some other brands, but in group below, the Klipsch has the highest sensitivity and is 3.4 dB higher than the average (2.83 volts/1 meter, anechoic). Brent Butterworth included these measurements in his hometheaterreview.com reviews of each of the speakers below.
Klipsch RP-280FA (92.5)

 

 

92.5dB/2.83v isn't unusual with a dual woofer speaker, especially when the actual impedance is 6 ohms, which is what the measurements indicate. 1 watt into 6 ohms is 2.44v, not 2.83v. What's more pertinent is that Klipsch claims 98dB/2.83v, and that's just plain old fashioned

Bill Fitzmaurice

 

Quote

If you consider anything Klipsch be sure to find the *real* sensitivity on them, not their "specs". Klipsch is known for inflating their sensitivity specification by 5-6dB on most/all speakers. One example.

klipsch spec---98dB
https://www.crutchfield.com/p_714RP2...c&awug=9015446

real sensitivity---92.5dB
http://hometheaterreview.com/klipsch...viewed/?page=2

Tom V.
Power Sound Audio