Wharfedale Diamond 220 Budget Speaker Review

[ctrl]

The authors found a strong correlation between predictions made by two models in particular ("DS" and "R(nonlin)") and subjective rating.

They also examined the correlation between the older THD and IMD metrics vs listener rating and found (as expected) very poor correlation (listener rating on the y-axis, distortion according to given metric on the x-axis):

One should take a close look at what is compared in the study.
It was compared how well an overall score for distortion correlates with the auditory impressions (THD score, IMD score, DS and R(nonlin) scores)

Certain survey methods were selected for this purpose.
But this has nothing to do with the usual surveys and evaluations of distortion measurements of loudspeakers.

Usually HD2, HD3, HD4, HD5 (and THD) are determined for harmonic distortions over almost the entire frequency spectrum (as far as the measuring system allows) and then evaluated using the measurement diagram.

In order to determine IMD (with is part of the multitone distortion) it is common practice for loudspeakers to do this with a multitone signal (with special distribution of the excitation frequencies over the audible spectrum). The evaluation follows also here usually by the evaluation of the measurement diagram.

What was done in the study?

The THD score was determined as follows:

So only at 1kHz the harmonic distortions were determined and then summed up with the usual procedure.

The IMD were determined as follows:

This method is of course not very useful for the determination of IMD of loudspeakers.

The study clearly shows that the used distortion scores for THD and IMD used to describe distortion in amplifiers for example (e.g. 0.1% THD@1kHz) do not correspond to the listener ratings and that there are better methods for this.

However, this does not mean that HD and MD measurements of loudspeakers are not useful or meaningless. The "DS" and "R(nonlin)" methods are nothing more than evaluations of MD measurements.

Here the multitone excitation used in the study:

Of course it would be great, especially for non-technical consumers, if there were a single score for loudspeaker distortion.

All the better if we could simply calculate a post-EQ preference score using either the Harman target curve or other selectable curves. Presumably there are limits to how much EQ a speaker can take before something else happens, like additional harmonic distortion or changes in directivity (or even phase distortion depending on how the EQ is implemented, right?). Otherwise we would all be EQing our speakers to perform like Genelecs.

The Olive Score is only an orientation value, which describes to a certain degree the possible sound and potential of a loudspeaker.

If @amirm comes to a different conclusion in his personal evaluation, it is unlikely to be due to distortions.

It's simply that a loudspeaker with less than optimal directivity can still sound very good if the crossover is carefully tuned.
And that a loudspeaker with very good directivity, with poor crossover tuning, can sound very good if the consumer's EQ is carefully adjusted.


But why can't Amir do this with every speaker?

Distortions can certainly play a role under certain conditions. If at 1kHz a -5dB dip occurs due to a suspension resonance, it's usually not a good idea to compensate this with EQ, so the "error" cannot be corrected.
If the crossover is badly done and for example the filter slope of the low midrange driver is too early or too steep, then it is also problematic to linearize the resulting dip by EQ, because then the tweeter is overloaded.

But what is probably much more common is the fact that you just can't find the optimal EQ (without spending a lot of time).

 

[andreasmaaan]

One should take a close look at what is compared in the study.
It was compared how well an overall score for distortion correlates with the auditory impressions (THD score, IMD score, DS and R(nonlin) scores)

Certain survey methods were selected for this purpose.
But this has nothing to do with the usual surveys and evaluations of distortion measurements of loudspeakers.

Usually HD2, HD3, HD4, HD5 (and THD) are determined for harmonic distortions over almost the entire frequency spectrum (as far as the measuring system allows) and then evaluated using the measurement diagram.

In order to determine IMD (with is part of the multitone distortion) it is common practice for loudspeakers to do this with a multitone signal (with special distribution of the excitation frequencies over the audible spectrum). The evaluation follows also here usually by the evaluation of the measurement diagram.

What was done in the study?

The THD score was determined as follows:

So only at 1kHz the harmonic distortions were determined and then summed up with the usual procedure.

The IMD were determined as follows:

This method is of course not very useful for the determination of IMD of loudspeakers.

The study clearly shows that the used distortion scores for THD and IMD used to describe distortion in amplifiers for example (e.g. 0.1% THD@1kHz) do not correspond to the listener ratings and that there are better methods for this.

However, this does not mean that HD and MD measurements of loudspeakers are not useful or meaningless. The "DS" and "R(nonlin)" methods are nothing more than evaluations of MD measurements.

Here the multitone excitation used in the study:

Of course it would be great, especially for non-technical consumers, if there were a single score for loudspeaker distortion.

Well, I mostly agree with you But see the context of my post, which was in response to @Francis Vaughan's post in which he said:

Yes distortion matters, but we still have little to no understanding of what makes for benign versus objectionable versus euphonic distortion.
A metric of level dependence would be interesting but mostly of academic value. Level dependence itself has a time dependence component. Frequency response often has similar issues and they would be useful.

So my intention was to show that distortion audibility and its relationship to subjective experience is not as much of a mystery as sometimes asserted (if I interpreted Francis' comment correctly).

And a secondary motivation for the post was to point out that the well-known Gedlee metric, while more useful than less sophisticated metrics, is not in fact the SOTA when it comes to current models of distortion perception.

Regarding your comment that:

"However, this does not mean that HD and MD measurements of loudspeakers are not useful or meaningless. The "DS" and "R(nonlin)" methods are nothing more than evaluations of MD measurements."

The purpose of the models is to correlate subjective perception with objective measurement. It seems therefore essential that the model use some objective measure of distortion. Do you disagree with this? Or do you take issue with it using a measure of IM distortion in particular? If the latter, what alternative would you suggest? The fact that the models correlate strongly with subjective ratings suggests to me that the objective measure chosen is an appropriate one.

Finally, I'm not suggesting that HD and IMD measurements of loudspeakers are useless or meaningless. They can be very useful if analysed carefully (for example, by looking at the frequency range in which distortion occurs, the order of harmonics or IM products, their dependency on level, etc. etc.). Sorry if that didn't come across clearly in the earlier post.

 

[ctrl]

So my intention was to show that distortion audibility and its relationship to subjective experience is not as much of a mystery as sometimes asserted (if I interpreted Francis' comment correctly).

And a secondary motivation for the post was to point out that the well-known Gedlee metric, while more useful than less sophisticated metrics, is not in fact the SOTA when it comes to current models of distortion perception.

Agree with both.
Are there any studies that have tested the Shorter/GedLee metric for correlation with listener ratings for speakers (independent of GedLee's own study)? Is the Shorter/GedLee metric based on HD measurements really hopelessly inferior to more modern methods based on MD measurements such as DS and R(nonlin)?

The purpose of the models is to correlate subjective perception with objective measurement. It seems therefore essential that the model use some objective measure of distortion. Do you disagree with this? Or do you take issue with it using a measure of IM distortion in particular?

My problem is that the study regarding HD and IMD is not transferable to speakers. The specification 0.1% THD@1kHz is used for amplifiers, but not for speakers.
Just wanted to emphasize that the results of the study cannot simply be transferred to the way HD and MD measurements are evaluated for speakers.
So there is no catfight

 

[andreasmaaan]

Agree with both.
Are there any studies that have tested the Shorter/GedLee metric for correlation with listener ratings for speakers (independent of GedLee's own study)? Is the Shorter/GedLee metric based on HD measurements really hopelessly inferior to more modern methods based on MD measurements such as DS and R(nonlin)?

Not that I know of. In the paper I linked earlier, the authors state, "In listening tests, the authors found a moderate correlation between this metric and the subjective impressions of artificially applied distortion on the magnitude of 0.67." However, scanning the paper to which they reference this statistic, I do not find any mention of the figure they give. Perhaps they have taken it from another Geddes/Lee paper and the citation is incorrect.

My problem is that the study regarding HD and IMD is not transferable to speakers. The specification 0.1% THD@1kHz is used for amplifiers, but not for speakers.
Just wanted to emphasize that the results of the study cannot simply be transferred to the way HD and MD measurements are evaluated for speakers.
So there is no catfight

Point taken I should have been more careful with the part of my post dealing with standard HD and IMD metrics. Didn't mean to imply that all measures of HD or IMD were useless, but just intended to point out that the standard metrics involving the translation of a single HD or IMD measurement into a figure are not so helpful. In hindsight, the correlations involving these mertrics were irrelevant to the point I was trying to make, anyway.

 

[Dennis Murphy]

While I understand your point and fully realize that right now less people use EQ than do, I would rather have the rating be based on what Amir finds while using EQ.
Many "audiophile" journalist rate speakers that cost $400 while powered by 5k amps, they clean their vinyl with moon dust and connect $1000 RCA wires. In the face of that I am completely down with some one doing something during the review process that actually positively affects the sound and I want to know what is possible with the speaker.
PEQ is also so easy to come by now in high quality - even completely FREE on a laptop or many phones. Because I am so happy with it's affects I would love to see reviews that promote it and thus open the gateway for more folks to dive in.
I realize there is a market for PEQ and other advanced EQ that is untapped now - tap it. As beautiful as "inherent" abilities are it is a daydream, nothing can affect HIFI more positively than DSP and advanced EQ (or at least PEQ). & really it is a much more accessible way to make many of the crossover mods you have made so generously for all these years - in fact it is even much better.

I don't disagree with your basic message. I certainly have no problem with Amir giving ratings with and without EQ. But this info is still basically for hobbyists, and it's still better for the speaker designer to get things right from the start, be it through a properly designed passive or active crossover and careful driver selection. If he or she messes up, then it's a headless panther for you. Again, I don't mind if Amir puts the head back on in a separate rating. Just on a personal note, I continue to be a little surprised at how long relics like me still have some relevance in the crossover department. Active crossovers dominate passives in every area except flexibility of choice in electronics. Yet they're a really hard sell. Fortunately, strictly in terms of audible results, you can pretty much equal the sound of an active crossover, or of an EQ'd speaker of any kind, if you follow the rules.

 

[andreasmaaan]

BTW @ctrl, the authors of that study also undertook an earlier study in which they modelled the distortion behaviour of real loudspeaker transducers and then applied the DS metric to the results of listening tests. I haven't read it (yet), but here it is.

And here's the study in which they develop the R(nonlin) metric in an effort to produce a model with stronger correlation (which apparently succeeded). Haven't read this yet, either. And also worth noting, AFAIK attempts have not been made to replicate these studies.

 

[restorer-john]

I don't disagree with your basic message. I certainly have no problem with Amir giving ratings with and without EQ. But this info is still basically for hobbyists, and it's still better for the speaker designer to get things right from the start, be it through a properly designed passive or active crossover and careful driver selection.

To me, it's just a manifestation of many audiophiles' need to endlessly tweak every part of their system, pretending they know more than the designer or believe they can somehow "improve" the design by poking around with some EQ.

The end result is endlessly moving goalposts and little satisfaction with anything. For me, I have zero interest in EQ'ing my speakers. I have many pairs (too many) and listen to each on their merits. I did digital PEQ back in the early 90s, 30 years ago, and it isn't the universal panacea people think it is. Just because your software allows it to be done easily these days, doesn't mean you should. Just like tone controls, filters and effects- they are best left well alone unless a recording (not a speaker) is deficient and wondering why it doesn't sound any better.

I imagine the ASR basement dwellers sitting there, diligently keying in PEQ settings in their software, in vain attempts to match what someone else, with completely different gear, ears and room thought was better.

 

[ace_xp2]

While some things may have reached a relative zenith thirty years ago, anything involving computation certainly wouldn't be on that list. I recall how hard it was to implement things like foobar a decade further on, and also how little was known to the average public diyer at the time. It's the technology, as opposed to the goalposts, that has moved.

 

[infinitesymphony]

There's no doubt EQ can improve frequency response in equipment with obvious deficiencies or to correct for room acoustics.

But I have to question the idea that EQ can make a $100 transducer equivalent to a $3,000 transducer (speakers, headphones, microphones, you name it). There are analogues in the recording world like the Slate VMS ML-1 virtual microphone system, which starts with a relatively clean microphone and applies frequency response curves to the signal in order to make it sound like other microphones. Would it work if they started with a Shure SM57?

If EQ can turn a 1.97 speaker into a 5.80 speaker, why bother ever buying different speakers if the SPL is high enough?

 

[thewas]

Wharfedale have gone to back porting with 12 series .Maybe the collaboration Karl Heinz (consultant) influenced that. Does it lower the driver and xo cost and easier in production assembly for back ported designs ?

Like almost everything the placement is a compromise, frontal port gives usually a dB or more SPL but has the disadvantage that mainly at 2-way speakers often parasitic mids are radiated to the listener.

 

[ROOSKIE]

I don't disagree with your basic message. I certainly have no problem with Amir giving ratings with and without EQ. But this info is still basically for hobbyists, and it's still better for the speaker designer to get things right from the start, be it through a properly designed passive or active crossover and careful driver selection. If he or she messes up, then it's a headless panther for you. Again, I don't mind if Amir puts the head back on in a separate rating. Just on a personal note, I continue to be a little surprised at how long relics like me still have some relevance in the crossover department. Active crossovers dominate passives in every area except flexibility of choice in electronic electronics. Yet they're a really hard sell. Fortunately, strictly in terms of audible results, you can pretty much equal the sound of an active crossover, or of an EQ'd speaker of any kind, if you follow the rules.

You are no relic.
You have never met me but I have followed your diy and commercial work online. Excellent stuff.
While I deff want to promote Dsp and PEQ and other advanced filtering, great passive design still has a long life left - plus it is a beautiful art.

 

[beagleman]

Correct me if I am wrong, but why do the distortion plots show LOWER distortion at around 350 hz for the 96db sweep compared to the 86 db sweep?

I would think if anything, it would rise higher?

 

[Angsty]

Should've got the soccer panther.

Actually, I think this one would get the Royal Guard saluting panther.

See it here...
https://www.audiosciencereview.com/...nts-of-cambridge-audio-duo-phono-preamp.6901/

 

[Angsty]

Actually, I think this one would get the Royal Guard saluting panther.

See it here...
https://www.audiosciencereview.com/...nts-of-cambridge-audio-duo-phono-preamp.6901/

The head and right hand of this pink panther is no more, sadly.

My bad. The Royal Guard panther was decapitated and is now the "headless" panther. What a shame. The up-side is that he sees a lot more use now than he would as the symbol of British measured excellence.

 

[Willem]

I am about to take delivery of a pair of modern looking white 220's at 125 euros. We have a garden room where we sometimes sit to drink coffee or read a book. I wanted something decent for a budget price, and I think I found it. I will use a spare 2x30 watt rms Tangent AMP 50 amplifier that will probably be fine for the purpose, fed by the analogue output of a CCA.
I have used a pair of Diamond 9.0s in a modest system with this amplifier before, and that worked fine until one of the speakers failed. The 220's should sound even better.

 

[Willem]

Do I take it that the grill to remove is the tweeter grill? I personally hate the look of naked speakers, but topless would be better than no clothing at all.

 

[Willem]

I just unpacked my Diamond 220s and decided to first try them in the main system, replacing my Quad electrostats and fed by an RME ADI-2 and Quad 606-2 power amplifier, but subwoofer turned off. I was pleasantly surprised playing Mahler's fourth: they were smooth and unfatiguing sounding without any nasties, which is saying quite something. My reservations were twofold. The first is that the soundstage seemed a bit narrow, and the second is that they did not seem too dynamic. But what can you expect from two small boxes at 125 euro a set? Even fit and finish were really rather good, although my wife quite rightly complained that the silver rings of the grills looked garish. Anyway, to address the limitations, I decided to turn on the sub, and see what difference it would make. Sound stage grew quite a bit wider (whatever that means) and the sound acquired a far more dynamic character. They still did not quite fill this large room, but admittedly I did not dare to unleash the full power of the amplifier.
I think I got far more than my money's worth and may buy a small cheap Elac S 5.2 subwoofer as well. Of course, my desktop ssytem, with Harbeth P3ESRs and a KEF Kube 8B sub is really better and sounds more natural, but it is remarkable how much quality you can get for so little.

 

[BYRTT]

Hi

I just unpacked my Diamond 220s and decided to first try them in the main system, replacing my Quad electrostats and fed by an RME ADI-2 and Quad 606-2 power amplifier, but subwoofer turned off. I was pleasantly surprised playing Mahler's fourth: they were smooth and unfatiguing sounding without any nasties, which is saying quite something. My reservations were twofold. The first is that the soundstage seemed a bit narrow, and the second is that they did not seem too dynamic. But what can you expect from two small boxes at 125 euro a set? Even fit and finish were really rather good, although my wife quite rightly complained that the silver rings of the grills looked garish. Anyway, to address the limitations, I decided to turn on the sub, and see what difference it would make. Sound stage grew quite a bit wider (whatever that means) and the sound acquired a far more dynamic character. They still did not quite fill this large room, but admittedly I did not dare to unleash the full power of the amplifier.
I think I got far more than my money's worth and may buy a small cheap Elac S 5.2 subwoofer as well. Of course, my desktop ssytem, with Harbeth P3ESRs and a KEF Kube 8B sub is really better and sounds more natural, but it is remarkable how much quality you can get for so little.

Thanks feedback and happy hear value is rater high, with reference to Amir's test data in a way hope you ran them with grills becuse that was eating a ton on performance side and then they can be better than what the first impression, left plot below is with grill verse right plot that is without grill, have fun ..

 

[Willem]

Since I temporarily needed my Harbeth P3ESR desktop speakers elsewhere, I installed the Diamond 220's in my desktop system. I am happy to report that they are doing fine in near field use, unlike my earlier Diamond 9.0s.

 

[DSJR]

Just reading this review again, I'm reminded that designer Peter Comeau used to like a controlled bit od 'sparkle' at 10khz or so. When he started out co-owning Heybrook over forty years ago, he probably didn't have much choice in all honesty, but today, it's just as much a personal preference thing I reckon.

Just to put how lucky 'we' are these days, I remember the UK well-reviewed Mission 70, made of what seemed like hardboard half-boxes sleeved together and selling for £99. they'd be around £325 if sold today. These Wharfedales and immediate descendants are in a different world technically at least and made possible by cheaper Chinese manufacture. Assuming they could be designed and made here, I'd suggest they'd be £500 or so.

P.S. I did read an earlier post almost sarcastic towards UK speaker design. may I please respectfully suggest our rooms aren't like many US built ones either in construction or size and it's almost certainly probably that speakers not liked here for response anomalies may well work fine in our generally near to mid-field environments. having said that, my pals 220's 'sound' great at moderate levels and not hugely well positioned either