Neumann KH 80 DSP Monitor Review

[Krunok]

Agree. I definitely think its best to accept the listening tests as informal for now now. This is something researchers spend a lot of effort doing.[/QUOTE]

Frankly, my opinion is that once you would actually EQ-ed all speakers response to follow the same target curve with some predefined precision pretty much the only thing they would differ at would be ammount of bass they are able to produce. The other thing would be some differences in their directivity (are they spreading the sound wide or narrow), but to listen to those differences you would probably have to widen LP a little so it is not a single narrow seat.

The above would of course be valid for good speakers only, bad speakers would still sound bad.

P.S. you are correct: 106dB at 0.3m equals to 95.54dB at 1m, which is quite loud.

As I mentioned in my post, one of the many variables that would need to controlled for is room acoustics.

Applying room EQ to follow the same target curve with some predefined precision is a way of controlling the room acoustics.

 

[maxxevv]

Thanks @DDF, I did think this was the most likely explanation. 90dB @1m (a realistic distance for a nearfield monitor) is quite loud =]

But the above comment made me take a second glance at the OP, so question @amirm. You said you did the measurement at 106dB @ 0.3m, equivalent to 90dB at 1m. On second glance that doesn't seem right. 106dB at 0.3m would be 95.5 dB, which would be very loud indeed and certainly explain the bass dip due to compression on a small monitor.

View attachment 47091

Typo, or am I missing something? Sorry, not trying to be a pain... I know speaker measurements and data presentation are a lot of work, even with the Klippel.



Thanks for sharing =] I assumed the mic was fine. Umik-1 is good enough for EQ in home theater purposes, but for measurements I got one calibrated from Cross Spectrum labs - which I believe calibrates the mic to an ACO pacific 7052E. Anyway, the mics definitely aren't a significant reason for the different results.



I definitely think its best to accept the listening tests as informal for now now. This is something researchers spend a lot of effort doing.

That's my thoughts too on the 90dB SPL at 1m. Didn't cross check the projected value, and 95dB SPL is very loud . Not something that can be sustained for nearfield listening, at least not to my ears.

Any tangible information/data on what would be a (more) sensible level at 1 meters anyone ?

 

[daftcombo]

Frankly, my opinion is that once you would actually EQ-ed all speakers response to follow the same target curve with some predefined precision pretty much the only thing they would differ would be ammount of bass they are able to produce. The other thing would be some differences in their directivity (are they spreading the sound wide or narrow), but to listen to those differences you would probably have to widen LP a little so it is not a single narrow seat.

The above would of course be valid for good speakers only, bad speakers would still sound bad.

Perhaps Amir's main goal is to find out which speakers are good, which are bad, which have good directivity, which don't.

Otherwise a simple on-axis measurement with REW would be sufficient.

 

[Krunok]

Perhaps Amir's main goal is to find out which speakers are good, which are bad, which have good directivity, which don't.
.

When I said "good speakers" I was referring to the speakers with good Klippel/spinorama measurements.

 

[napilopez]

That's my thoughts too on the 90dB SPL at 1m. Didn't cross check the projected value, and 95dB SPL is very loud . Not something that can be sustained for nearfield listening, at least not to my ears.

Any tangible information/data on what would be a (more) sensible level at 1 meters anyone ?

Yeah, just want to make sure measurements are at a realistic listening level for a given speaker. And that completely explains the bass issue, as the Neumanns will definitely compress at 95 dB.

Of course, you'll want a larger speaker meant for far-field use to be able to handle such volumes without a problem - and you want some headroom for dynamic peaks. But it's probably a bit unfair for smaller monitors.

I believe 83dB or so is the volume many mixing people use? Maybe someone with mixing experience can chime in. If I recall correctly, 85dB average is THX reference level for movie theaters, but AV receivers tend to use 75dB at the listening position ("0" on your av receiver once calibrated). I already find 75 dB average a bit louder than comfortable . But I have a pretty low noise floor - a blessing for an NYC apartment.

CTA-2034-A has recommendations for referencing performance to different SPL levels at the listening position(75,85, 95,105 dB) but from skimming that section, it seems like a whole lot of work that's not worth the effort. In any case, it's referenced to a four-meter listening distance, which definitely isn't realistic for a majority of studio monitors.

 

[Krunok]

CTA-2034-A has recommendations for referencing performance to different SPL levels at the listening position(75,85, 95,105 dB) but from skimming that section, it seems like a whole lot of work that's not worth the effort. In any case, it's referenced to a four-meter listening distance, which definitely isn't realistic for a majority of studio monitors.

As 105dB at 4m equals 117dB at 1m it is hardly realistic for 99.95% of home speakers.

 

[Krunok]

Frankly, my opinion is that once you would actually EQ-ed all speakers response to follow the same target curve with some predefined precision pretty much the only thing they would differ at would be ammount of bass they are able to produce. The other thing would be some differences in their directivity (are they spreading the sound wide or narrow), but to listen to those differences you would probably have to widen LP a little so it is not a single narrow seat.

The above would of course be valid for good speakers only, bad speakers would still sound bad.

@mitchco Speaking of that, haven't you done an experiment that actually proves that? It was your JBL and some small KEFs coupled with 2 subs or something like that, right?
Maybe you can post a link so we can read it again in the light of these new Klippel measurements.

 

[napilopez]

As 105dB at 4m equals 117dB at 1m it is hardly realistic for 99.95% of home speakers.

Haha, well it doesn't quite work that way, as the calculation takes into account room gain and stereo playback and such.

The formula they give is:

SPLIn-Room = MaxSPL + 3 dB + 6 dB – 12 dB

I believe that's accounting for+3dB for Stereo playback, +6dB for room gain, and -12dB for distance.

So if I remember my algrebra correctly, you would just need a max SPL of 108dB at 1m to get 105dB at 4m.

 

[Krunok]

Haha, well it doesn't quite work that way, as the calculation takes into account room gain and stereo playback and such.

The formula they give is:

SPLIn-Room = MaxSPL + 3 dB + 6 dB – 12 dB

I believe that's accounting for+3dB for Stereo playback, +6dB for room gain, and -12dB for distance.

So if I remember my algrebra correctly, you would just need a max SPL of 108dB at 1m to get 105dB at 4m.

I didn't calculate anything, I just punched the numbers in the calculator from your post.

 

[napilopez]

I didn't calculate anything, I just punched the numbers in the calculator from your post.

Haha I figured, I also at first thought that seemed way too loud too until I saw the formula. I'd be very concerned for my hearing if I were constantly exposed to 117dB peaks. 108dB is bad enough!

 

[thewas]

@mitchco Speaking of that, haven't you done an experiment that actually proves that? It was your JBL and some small KEFs coupled with 2 subs or something like that, right?
Maybe you can post a link so we can read it again in the light of these new Klippel measurements.

https://audiophilestyle.com/ca/revi...ker-comparison-with-binaural-recordings-r768/
I am of course not Mitcho but really appreciate his articles and book about DRC and have also a pair of LS50s with subs and large JBLs

 

[Krunok]

https://audiophilestyle.com/ca/revi...ker-comparison-with-binaural-recordings-r768/
I am of course not Mitcho but really appreciate his articles and book about DRC and have also a pair of LS50s with subs and large JBLs

I don't mind you're not Mitch as long as you're posting the right stuff.

 

[Andreas007]

I disagree. Listening tests without comparison is worthless imo.

Quality is relative to something, so it only makes sense to use a known reference so that both Amir and all readers have the same reference point to judge respective qualities from. It's very good that this reference point is cheap, have good objective sound quality and is easy for most people to borrow an ear to so that we can understand where Amir is coming from and thus know what it means when he describes certain aspects of speakers relative qualities.

Without a reference, it's all fantasy talk.

Got your point. But then I have to emphasize that I don't accept the JBL 305P Mark ii as a "reference" to which all other speakers are compared in future.

 

[mitchco]

Thanks @Krunok and @thewas_ Just as an aside, here is another example of two different speakers sounding the same:

D&D 8c compared to Kii THREE at the LP in a 9ft equilateral triangle. This was not using any "room eq" just the onboard controls for both active speakers when I had both of them in my room.

A zoomed in view, well above the room's transition frequency:

A comment from Martijn the designer of the D&D 8c:

"I've had the Kii's and the 8c's side by side in my living room for a while. The Kii's too are remarkably good speakers. With just some subtle EQ the two could be made to sound very similar on most program material - to the extent that I might not be able to distinguish them in a proper blind test. I'm still amazed sometimes by the extent to which differences in sound can be explained by frequency response."

That was my experience as well. I found it difficult to tell the two apart. The only subjective difference I could tell was the bass on the Kii THREE's sounded "dryer" than the D&D's, which their bass sounded "warmer." But it was very subtle, otherwise I doubt in a blind test I could tell the difference.

I have had about a dozen different speakers through my room over the last five years, the latest being the amazing Purifi 6.5 woofers. And having an arsenal of room eq at my finger tips, I have, of course, applied this to all of those speakers. More often than not they all sound almost indistinguishable with a target applied. The real difference is in the directivity of each loudspeaker and how much of the room is illuminated by the speaker above the transition frequency.

Sorry for the OT.

 

[Krunok]

Very good post!

Here is a segment of your graph starting with 600Hz as boundary region above transition frequency seems to end there so your point is even more emphasized.
And yes, I'm aware that when it comes to skills with graphics I will never become @BYRTT

 

[carlob]

Not taking into account the "informal" listening test, do we all agree that the Neumann measure better than the JBL?

 

[Krunok]

Not taking into account the "informal" listening test, do we all agree that the Neumann measure better than the JBL?

IMO they do.

 

[DDF]

Yes, that's why Prof. Goertz and many others use for multitone distortion measurements (IMD and other) a signal according to the EIA-426B standard

IEC-60268-1-1985 can be used as well. In 1996 Peter Chapman (AES preprint 4277) compared it to many CDs by genre and found good matching.

I've always weighted my multitone spectrum using Chapman's numbers vs IEC, but both work.

Amir mentioned his is designed for low crest factor, but I like exercising realistic crest factors.

I also use Blackman Harris windows. I discussed this with John Risch many years ago, who was with Peavey. John wrote a multitones AES paper ("A New Class of In-Band Multitone Test Signals" AES Preprint 4803, presented at the 105th Convention of the Audio Engineering Society, September 26-29, 1998, San Francisco, California) and he agreed: "I [John] used a Blackman-Harris window, similar to a straight Blackman, but yes, these types give better isolation of the distortion products to a given set of bins."

Back when I worked on this for a living, I tried using burst PHI tones to measure the multitone off a loudspeaker. The B&K microphones I used had distortion low enough to facilitate it, but the smaller mic pre-amps actually contributed more distortion and were a limiting factor. Another problem was the spectral leakage in the FFT was too large to allow low level distortion to be seen

Low order distortion products are easily masked by the fundamental (and why audibility requires high % distortion), but 7th and 9th order are highly objectionable and the ear's filter bandwidth doesn't extend high enough to mask. I have used with some success a band limited version of the multitone where it clearly allows 7th or 9th to be seen in-band. John used to actually colour code his test outcomes so these higher harmonics pop out of the graph via a heat map, without having to band limit the signal. Very neat addition.

What test levels to use when listening is tricky as well. The ear's ERB widens with higher sound pressure levels, and provides more masking. If room noise is low enough so that the harmonic components aren't masked by noise, the ear may actually have an easier time hearing the distortion at lower SPLs than high.

 

[carlob]

IMO they do.

And I agree. That said I would expect that compared under the same conditions in the same room they should also sound better, which is consistent with my experience. I like all the theory but this is all I need to know from a consumer standpoint.

 

[Krunok]

IEC-60268-1-1985 can be used as well. In 1996 Peter Chapman (AES preprint 4277) compared it to many CDs by genre and found good matching.
View attachment 47099
View attachment 47100

I've always weighted my multitone spectrum using Chapman's numbers vs IEC, but both work.

Amir mentioned his is designed for low crest factor, but I like exercising realistic crest factors.

I also use Blackman Harris windows. I discussed this with John Risch many years ago, who was with Peavey. John wrote a multitones AES paper ("A New Class of In-Band Multitone Test Signals" AES Preprint 4803, presented at the 105th Convention of the Audio Engineering Society, September 26-29, 1998, San Francisco, California) and he agreed: "I [John] used a Blackman-Harris window, similar to a straight Blackman, but yes, these types give better isolation of the distortion products to a given set of bins."

Back when I worked on this for a living, I tried using burst PHI tones to measure the multitone off a loudspeaker. The B&K microphones I used had distortion low enough to facilitate it, but the smaller mic pre-amps actually contributed more distortion and were a limiting factor. Another problem was the spectral leakage in the FFT was too large to allow low level distortion to be seen

Low order distortion products are easily masked by the fundamental (and why audibility requires high % distortion), but 7th and 9th order are highly objectionable and the ear's filter bandwidth doesn't extend high enough to mask. I have used with some success a band limited version of the multitone where it clearly allows 7th or 9th to be seen in-band. John used to actually colour code his test outcomes so these higher harmonics pop out of the graph via a heat map, without having to band limit the signal. Very neat addition.

Hmm.. Only 10dB of difference between 50Hz and 10000Hz as shown in Figure 6 doesn't really look realistic to me. I know this wouldn't disprove it but with 10 songs I just tried with Audacity all had at least 25.