Klipsch Roy Delgado explaining why Klipsch measures so bad.

[Chris A]

Y'all might find this still-current thread at AK of some interest vis-a-vis contemporary Klipsch efforts to stay current with their Heritage models.

New changes in Klipsch's Heritage series

Over on the K-forum, Mike Murgalo (user:MMurg) has been chronicling Klipsch's new changes to its Heritage series loudspeakers. Some of those changes include: Now using straight-sided midrange horns in the Klipschorn, La Scala, and Cornwall, replacing the 1962-vintage K-400 series collapsing...

audiokarma.org

That was me. The main objections I raised there are pretty esoteric compared to the subject of the thread here. Mostly, it was about Klipsch's use of fixed DSP settings--no doubt a constraint placed on Roy by another group within his company, instead of providing a user interface to the Klipsch DSP box settings like any other DSP box you can find today. Roy was the guy that got a bunch of 1st-gen Jubilee owners to use DSP instead of passives starting back in 2006 (myself included), so the issue there isn't about Roy.

Another decision to reduce the La Scala AL6 woofer diameter to 12" from 15" (a single woofer--which apparently was Roy's call) in order to reduce the F3 by 10 Hz by using an internal horn port from the back box volume, but also halving the woofer area, was other area that I personally didn't agree with. Instead, I think that La Scala owners should probably invest in one or more horn-loaded subs, like one of the other tapped horn sub designs that Tom Danley designed, and leave off internally venting the AL6 bass bin design. This isn't a strong objection on my part, however.

Chris

 

[PristineSound]

I’m still curious about the alleged defects of the Spinorama measurement suite, which is much more relevant for me than whether one or another design should be made without my money.

First, I think this thread took a turn.

I originally posted that Roy Delgado from Klipsch answered the question: "Klipsch [not any specific model, but Klipsch in general] are not known to measure the best. . .why?"

And his answer in paraphrase is that: "How you measure it makes a difference" Power response, efficiency is Klipsch's key priority and he used the Klipsch horn as an example that it was designed to be placed in the corner.

The key topic of focus is, was Roy's explanation satisfactory as to why Klipsch doesn't measure well? I say no, because it came across as him (a) discrediting the validity of the spinaroma, (b) it also appears that Roy is trying to justify why Klipsch doesn't measure well by stating a speaker is designed to be placed in the corner as if that in itself justifies all the ailments and flaws of Klipsch's not so great measurements. You can go read why I said that in my previous posts.

The secondary topic of focus is: Klipsch doesn't perform well on the spinaroma. However, I don't believe anyone has said so far, they are terrible on the spin, at least not with the new Klipsch models that I found on Spinaroma.org

In fact, their newer models are actually not bad at all. Take this RP-5000F II (MSRP $1,200) for example. Bass extension if pretty good, on and off axis linearity is decent. DI and ERDI is fairly linear. Horizontal radiation is fairly respectable above tweeter crossover point. And the vertical radiation is also respectable, with commendable lobing control.

Now to answer your question, what is the defect on the spin with Klipsch? Well, it depends on which Klipsch speaker you are referring to. Let's take their Forte IV and examine it.
On the spin, the on-axis linearity is somewhat sub-par, at around 5k, there is a significant bump, which what appears to be a low enough of a Q factor to be audible with a steep roll of at around 15kHz, though may not be an issue with people who are older than 35 as a result of upper frequency hearing loss. The DI and ERDI is quite choppy, especailly that dip at around 1.5kHz (a critically audible band), making it hard to EQ, definitely will need some room treatment to tame the dissimilar reflected sound from the sidewalls.

Now let's compare this to a Ascilab C5B at 1/5th the cost of the Klipsch Forte IV. (Now, I will say this though, those Ascilab folks have the benefit of learning the latest and greatest science)

On the spin, look at the on-axis linearity, and look at early reflections, nearly identical, which takes us to the DI and ERDI, almost a straight line, freaking impressive man. And this Ascilab costs $200 less than the, not too shabby RP-5000F II but measures significantly better.

EDIT: I forgot to mention the radiation pattern of the Ascilab C5B, absolutely stunning, probably as ideal as you can come against. . .this is a thing of beauty, I am considering printing this out and hanging it on my wall for decor.

 

[ahofer]

First, I think this thread took a turn.

I originally posted that Roy Delgado from Klipsch answered the question: "Klipsch [not any specific model, but Klipsch in general] are not known to measure the best. . .why?"

And his answer in paraphrase is that: "How you measure it makes a difference" Power response, efficiency is Klipsch's key priority and he used the Klipsch horn as an example that it was designed to be placed in the corner.

The key topic of focus is, was Roy's explanation satisfactory as to why Klipsch doesn't measure well? I say no, because it came across as him (a) discrediting the validity of the spinaroma, (b) it also appears that Roy is trying to justify why Klipsch doesn't measure well by stating a speaker is designed to be placed in the corner as if that in itself justifies all the ailments and flaws of Klipsch's not so great measurements. You can go read why I said that in my previous posts.

The secondary topic of focus is: Klipsch doesn't perform well on the spinaroma. However, I don't believe anyone has said so far, they are terrible on the spin, at least not with the new Klipsch models that I found on Spinaroma.org

In fact, their newer models are actually not bad at all. Take this RP-5000F II (MSRP $1,200) for example. Bass extension if pretty good, on and off axis linearity is decent. DI and ERDI is fairly linear. Horizontal radiation is fairly respectable above tweeter crossover point. And the vertical radiation is also respectable, with commendable lobing control.
View attachment 447083

View attachment 447084

View attachment 447085


Now to answer your question, what is the defect on the spin with Klipsch? Well, it depends on which Klipsch speaker you are referring to. Let's take their Forte IV and examine it.
On the spin, the on-axis linearity is somewhat sub-par, at around 5k, there is a significant bump, which what appears to be a low enough of a Q factor to be audible with a steep roll of at around 15kHz, though may not be an issue with people who are older than 35 as a result of upper frequency hearing loss. The DI and ERDI is quite choppy, especailly that dip at around 1.5kHz (a critically audible band), making it hard to EQ, definitely will need some room treatment to tame the dissimilar reflected sound from the sidewalls.

View attachment 447086

Now let's compare this to a Ascilab C5B at 1/5th the cost of the Klipsch Forte IV. (Now, I will say this though, those Ascilab folks have the benefit of learning the latest and greatest science)

On the spin, look at the on-axis linearity, and look at early reflections, nearly identical, which takes us to the DI and ERDI, almost a straight line, freaking impressive man. And this Ascilab costs $200 less than the, not too shabby RP-5000F II but measures significantly better.

View attachment 447087


EDIT: I forgot to mention the radiation pattern of the Ascilab C5B, absolutely stunning, probably as ideal as you can come against. . .this is a thing of beauty, I am considering printing this out and hanging it on my wall for decor.
View attachment 447093
View attachment 447094

Oh dear, thank you for this. I’m afraid I meant the problems with the test method itself, answered above.

 

[Bjorn]

Polar sonograms are much more useful, I've found, than estimating early reflections from a "typical room" and room placement.

Absolutely. It contains what we need to both see how the speaker itself behaves and how it will interact with the room.

 

[Bjorn]

EDIT: I forgot to mention the radiation pattern of the Ascilab C5B, absolutely stunning, probably as ideal as you can come against. . .this is a thing of beauty, I am considering printing this out and hanging it on my wall for decor.
View attachment 447093
View attachment 447094

The horizontal shows a typical collapsing polar with only uniform directivity in the higher frequencies and abrupt loss of directivity below 1000 Hz. That's not good at all and means and a great shift in the tonality when placed in a reflective room. The vertical extends somewhat lower, but still not broadband directivity which is the ideal. And besides some narrowing it also shows a crossover frequency at a a region which we are very sensitive to. So not great at all.

I don't think you really understand what a great measuring speaker is.

 

[PristineSound]

The horizontal shows a typical collapsing polar with only uniform directivity in the higher frequencies and abrupt loss of directivity below 1000 Hz. That's not good at all and means and a great shift in the tonality when placed in a reflective room. The vertical extends somewhat lower, but still not broadband directivity which is the ideal. And besides some narrowing it also shows a crossover frequency at a a region which we are very sensitive to. So not great at all.

I don't think you really understand what a great measuring speaker is.

Then show me a great measuring speaker.

Let me guess, it's one of your very own speakers?

 

[Sokel]

Any one who wants to know if the design of the khorns are bad engineering or a choice can have a deeper look here:

North Reading Engineering

You get the picture, don't you?

As far as properly put in a room they are grander than life if this tune is your cup of tea.
They are in the group of these speakers where effortless playback is the goal, something that can't be tricked by smaller, "smarter" ones.

 

[Bjorn]

Then show me a great measuring speaker.

Let me guess, it's one of your very own speakers?

Again, turning the discussion into something else.

The fact is that the Klipsch Forte IV polar measurements you posted are better in several areas than the Ascilab C5B. While it's not without flaws and can be improved in several areas, the result is a more overall correct tonality when placed in an actual room. Plus of course there are aspects we don't see in the measurements. Horn loading generally offers a more illusion life like and dynamic presentation. There's a good reason why these speakers have been very popular. Are they perfect? Absolutely not and it's possible to achieve a good number of improvements.

I would careful to judge and critize something one doesn't have much insight into.

 

[Chris A]

Then show me a great measuring speaker. Let me guess, it's one of your very own speakers?

I don't believe Bjorn can reply to this effectively, since any reply he makes to this appears like personal bias.

I can say that Bjorn's loudspeakers are first and foremost concerned with directivity control and the benefits of horn loading. I'm sure they subjectively and objectively blow away virtually anything else that can be proposed. His designs are clearly not "well below the knee of the CAIV curve". Quite the contrary.

I can also refer you to his book (co-authored with Thomas Dunker) as a very good source for answering many questions about horns and horn loading, both theoretically and historically: https://www.hornspeakersystems.info/, the first such general source on that subject that I can recall since both the Beranek and Olson texts of the 1950s.

Chris

 

[Arindal]

Another decision to reduce the La Scala AL6 woofer diameter to 12" from 15" (a single woofer--which apparently was Roy's call) in order to reduce the F3 by 10 Hz by using an internal horn port from the back box volume, but also halving the woofer area, was other area that I personally didn't agree with.

But a similar concept did work in the Jubilee pretty well, did it not?

 

[Chris A]

Any one who wants to know if the design of the khorns are bad engineering or a choice can have a deeper look here:

North Reading Engineering

You get the picture, don't you?

As far as properly put in a room they are grander than life if this tune is your cup of tea.
They are in the group of these speakers where effortless playback is the goal, something that can't be tricked by smaller, "smarter" ones.

John Warren has been around for a long time on the K-forums. His specialty is passive crossover design based on electrical and acoustic measurements and simulation (i.e., not rhetoric or haranguing).

With the just-announced change in the Khorn design (AK7 with DSP option), many of the issues with this largely 1959 Khorn design were corrected in the areas of crossover design, amplitude response and time alignment.

The first version of the Khorn was originally designed as a two-way in 1948, then a tweeter was added in ~1959, about when recordings increased their high frequency bandwidth from 12 kHz to 20 kHz and started to be released in stereo format. Paul Klipsch was an enthusiastic supporter of stereo for home hi-fi, and in fact was the first real proponent of three-channel stereo.

But a similar concept did work in the Jubilee pretty well, did it not?

It apparently did not. The Heritage Jubilee (2nd-gen) bass bin uses two 12" woofers, not one, i.e., about the same area as a 15" woofer. Roy tried to reduce the design to one 12" woofer, but was not successful.

I've got a little paper on the differences between these two Jubilee designs that can be perused to show the differences and ways for 1st-gen Jubilee owners to avoid having to upgrade to the 2nd-gen design, but still get all the advantages of the 2nd-gen. I haven't seen any measurements of relative AM distortion with respect to the 1st-gen bass bin Roy designed for PWK in the late 1990s. I'm reasonably sure that isn't something that Roy would be very forthcoming with.

Chris

 

[PristineSound]

Again, turning the discussion into something else.

wow, you are bending logic to the 4th dimension.

First time, you commented that you would love to design a corner only speakers, so I said then design away? You didn't like that response, why? What were you expecting or hoping me to say to a comment like that?

Now you said what I shown isn't an excellent speaker, any logical person would come back and ask them what would be? And you are saying I'm turning the discussion into something else?

Again, what were you wanting or hoping my response be?

The fact is that the Klipsch Forte IV polar measurements you posted are better in several areas than the Ascilab C5B. While it's not without flaws and can be improved in several areas, the result is a more overall correct tonality when placed in an actual room. Plus of course there are aspects we don't see in the measurements. Horn loading generally offers a more illusion life like and dynamic presentation. There's a good reason why these speakers have been very popular. Are they perfect? Absolutely not and it's possible to achieve a good number of improvements.

I would have appreciated it if you just responded with this part and to conduct an adult-like conversation. This would have been a very interesting and fun conversation.

I would careful to judge and critize something one doesn't have much insight into.

Was this necessary? Maybe it would have been more professional of you to have leave this part and the first part out? As an company interacting with consumers where all other consumers can witness, one would imagine you would want to represent your brand in the most professional way. Just a little life and business advise.

Between the incoherent logic, how you want to dictate how the conversation should go and the insults, you are not worthy of further interaction. You will be ignored moving forward and any further insults or personal attacks will be reported.

 

[PristineSound]

I don't believe Bjorn can reply to this effectively, since any reply he makes to this appears like personal bias.

Doesn't matter, an objective analysis would have ensue, if he said his horn is the best, I would have asked for data and he would have the opportunity to explain why.

 

[PristineSound]

@Chris A btw there is no data on the Klipsch Horn and I have not said anything bad about it. There is data on the Forte and Heresy and those data does not show too well which I pointed out to. And of course, this started with me taking exception to Roy's interview, particularly a speaker being designed just for corners of a room.

Now if there are horn or Klipsch enthusiasts, I would love for them to take this opportunity to explain the scientific reasoning why they don't measure well on the spin but would sound good. Use this opportunity to elaborate what Roy left out in his explanation? This could be an educational opportunity for me and others.

 

[M240i]

@PristineSound If you're getting this irritated about a topic like this, it's probably time to take a breath.
There's no law now (and never has been) that says you can't design a speaker to be used in a room corner.

 

[PristineSound]

@PristineSound If you're getting this irritated about a topic like this, it's probably time to take a breath.
There's no law now (and never has been) that says you can't design a speaker to be used in a room corner.

Irritated at the personal insults and attacks? Moderately yes, it's just not necessarily.

Now I do recognize my scepticism of Roy's explanation and the concept of corner only speakers for some Klipsch fans, they may take offense to it. So dissent is not allowed anymore? No one is allowed to question or be a sceptic? Isn't that the cornerstone of science?

Irritated at the topic, absolutely not. I'm still trying to understand why a speaker design just for the corners of a room will somehow magically remediate all the ailments and flaws as it is shown in the Spinaroma as Roy has alluded to. I have pointed to the data of the Heresy and Forte and my interpretation as to why such argument doesn't hold water. Now if Roy's comment is only for the Klipsch Horn and no other models, then there is no data to analyze. . .and still leaves other questions unanswered and hence his explanation on this interview is unsatisfactory to me.

Forget about why anyone would design a speaker just for corners of a room and nowhere else, that is a matter of philosophical debate.

 

[Arindal]

Roy tried to reduce the design to one 12" woofer, but was not successful.

May I ask what was the shortcoming of this decision in our opinion?

I am aware that the Heritage Jubilee uses two 12". Was referring to the internal arrangement with reflex vent and horn kind of cascaded, if you want. Tbh, I had been expecting nothing good from that when I saw the sketches, but was positively surprised by the bass performance.

 

[hvbias]

Aside from one very specific Klipsch model (maybe not even be listed on their website as it's intended for professional use) every single Klipsch I've heard sounded dreadful.

 

[Chris A]

May I ask what was the shortcoming of this decision in our opinion?

It was never disclosed, but as you're asking for opinions, I think that it could be the rise in AM distortion at listenable levels. There is about 20 dB of EQ boost that's in the bass channel at 20-25 Hz relative to ~100 Hz (i.e., 10x the amplitude) which complicates the problem of AM distortion due to a really big EQ boost. Here is a plot of the EQ curves coming out of the Klipsch DSP box (LF and HF):

Chris

 

[AnalogSteph]

The fact is that the Klipsch Forte IV polar measurements you posted are better in several areas than the Ascilab C5B. While it's not without flaws and can be improved in several areas, the result is a more overall correct tonality when placed in an actual room.

So the much larger speaker retains better directivity in the lower frequencies, what a surprise. I'm not sure whether I'd want to pay for that with several glaring coloration issues though.

Maybe one of these as a compromise?