GR Research LGK 2.0 Speaker Review (A Joke)

[tomtoo]

Nobody should talk bad about the kh80dsp. Its the only speaker were its proofen by measurements that you can use them as thermometer.

 

[tomtoo]

Yes he did measure distortion.

Order of magnitude lower.

Neumann KH 80 DSP Speaker Measurements: Take Two

A few weeks ago I reviewed the Neumann KH80 DSP powered monitor. The measurements while very good, did not match manufacturers published graph which showed dead flat on-axis response. Third-party measurements had shown the same so objection was raised that my measurements must be in error. I...

www.audiosciencereview.com

Please do some research first before posting these absolute statements. Maybe ask a question instead if you don’t know. Nothing wrong with not knowing or not finding.

It makes no sense to compare a kh80dsp to this speaker. Its like comparing a lilienthal glider to a f16. When the only thing to compare them is the price.

 

[Gringoaudio1]

This speaker reminds me of the enthusiastic experiments on DIYAudio 12-15 years ago with the Tangband W3-871 3”driver. It or a similar version was used in Logitech computer speakers at the time as well.
Transmission lines and boxes of all sizes were tried to get some bass out of these. The experiments I did with this driver marked my return to hifi and although they sounded great compared to the boom boxes I’d been reduced to for years I moved on to better drivers ultimately using Scanspeak Revelators in my final DIY attempts.
Any attempt to commercialize anything in low volume will result in uncompetitive pricing compared to mass manufactured items.
Anyone who buys Danny’s single driver speaker would be better off following the DIYAudio forum on single driver speakers and buying raw speaker drivers. But not everyone has the means to build cabinets so I guess he serves a need.
But claiming that it performs well is a stretch.

 

[DSJR]

As I see it, when you're starting out, you can get a pair of small full range drivers, shove 'em in a box and get a noise out of them. I'd expect someone to do this for a hundred quid/dollars tops frankly - for fun!!! To sell this garbage for a few hundred is pushing it too far and as for a grand ready made? here in the UK, there's a huge used market in what's left of the audiophile industry which has all but killed off the new products at this level. I mean, nobody here buys them apparently, but the Wharfedale Linton heritage sells for around a grand and a bit with stands too and it's a bloody three way and not bad at all I gather...

 

[voodooless]

It makes no sense to compare a kh80dsp to this speaker.

Been there, done that

GR Research LGK 2.0 Speaker Review (A Joke)

Well, that was fun :cool: Nothing much unexpected here. With 2.5mm of apparent Xmax, you should get about 86 dB at 100 Hz/1m, and even that seems to be distorted, so the best guess is that the real Xmax is just around 1mm. The reflex tuning only can do so much to extend the inevitable… That...

www.audiosciencereview.com

 

[tomtoo]

Been there, done that

GR Research LGK 2.0 Speaker Review (A Joke)

Well, that was fun :cool: Nothing much unexpected here. With 2.5mm of apparent Xmax, you should get about 86 dB at 100 Hz/1m, and even that seems to be distorted, so the best guess is that the real Xmax is just around 1mm. The reflex tuning only can do so much to extend the inevitable… That...

www.audiosciencereview.com

For people that dont know, 10dB more you could also translate to 10 times more power in the amp. So compare a 10w amp to a 100w amp and say there is no difference in the power.

 

[voodooless]

For people that dont know, 10dB more you could also translate to 10 times more power in the amp. So compare a 10w amp to a 100w amp and say there is no difference in the power.

I will still just sound twice as loud

 

[tomtoo]

I will still just sound twice as loud

What i woud call a difference, to double again you need 1kw. Where we come to the big boys.

 

[Robin L]

This is a review and detailed measurements of the GR Research "Little Giant Killer" (LGK) 2.0 bookshelf speaker. It comes in various forms from a kit ($313) to fully finished pair ($1,038). Our DIY expert @Rick Sykora built my sample using the flatpack ($100):
View attachment 211673
Rick had to do the round over on the two edges per company recommendation as the flatpack is supplied with sharp edges. The build is superb and solid. Here is the back with the famous "tube connectors" and slot port:
View attachment 211674

Internal structure is complex due to that port so unless you are a serious woodworker, you need to get the flatpack.

The main driver is a tiny "full range" 3 inch unit. This allowed the cabinet to be small which I appreciated. Then again, there are plenty of active speakers which are the same size. Here is a comparison to the Neumann KH80DSP which sells for the same cost:
View attachment 211675

They are almost the same depth as well. Of course, the Neumann comes with built-in amplifier and DSP which the GLK 2.0 lacks.

Subjective claims in company video claims sound that is smooth and beats many larger speakers (hence the name).

You may be wondering by now why the title has the word "joke" in it. I reached out to company asking for a sample for review. Company owner, Danny Ritchie answered me saying he had no interest in providing me one. And that he and others think my reviews are a joke because I don't know how to listen to a speaker, don't have the right treated room, etc. On measurements he said he already provides them so nobody needs more information. I explained to him why his measurements are insufficient and again he repeated that nothing more is needed and that measurements like distortion are useless.

Anyway, we were then forced to purchase a pair for testing.

Measurements that you are about to see were performed using the Klippel Near-field Scanner (NFS). This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber. In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.

Reference axis is approximately the center of the tweeter.

GR Research LGK 2.0 Measurements
As usual we start with our "spin" graph:

View attachment 211676

At first this looks radically different than what the company shows:

View attachment 211687
I have circled some of the reasons the two graphs look different. Danny is using improper and heavy filtering (1/3 octave) for his measurements. This gets rid of the myriad of variations you see in my graph. He also uses gated response to get rid of room reflections which in the process removes any resolution below a few hundred Hertz. This is why his graph starts at 200 Hz rather than 20 Hz.

Rick was kind enough to post process mine to his resolution and chart dimensions and correlation was good.

Back to the spin, on-axis response look fairly flat. There is a notch where I think his baffle step loss filter is but is narrow so likely not audible. Overall, a good showing there.

Near-field response shows cabinet/port resonance interference:
View attachment 211678


The single driver is too large compared to a typical tweeter. This means that the sound starts to focus/beam as frequencies go up. This shows up in a number of measurements starting from early reflections in the form of high frequency loss:
View attachment 211679

Predicted in-room response (far field) as a result shows similar droop:
View attachment 211680

Still, this is a reasonable response.

Back to beaming, we see it clearly in the beam width and directivity plots:
View attachment 211681


View attachment 211682
The picture is nearly the same vertically due to use of a single driver:
View attachment 211683

So has the company cheated the laws of physics? Well, not quite. Let's look at distortion at 86 dBSPL:
View attachment 211684

Note: both left and right at the same graph at 86 dBSPL. Not 96 dB. Right one simply zooms out to show that distortion has risen to nearly 100%! Now, some of that is beyond the reach of the speaker but looking at the left graph we see that massive distortion reaches out to nearly 500 Hz. Second harmonic of that lands at 1 kHz where our hearing starts to become very sensitive. So bass distortion is likely quite audible.

Worried that it could not handle 96 dBSPL, I lowered the level to 90 dBSPL and ran the distortion test again:

View attachment 211685

Near the start of the sweep, speaker started to crackle which then went away above that frequency. Clearly it can't handle that but even 86 dBSPL is poor as I showed earlier.

Impedance is higher than average for the class which is good:
View attachment 211686

Something strange is going on as far as resonances though for the graph to become rough below 200 Hz. My measurements here are quite high resolution compared to what others run so this may not be visible in other people's tests.

Company shows a CSD/waterfall which looks clean. Mine does not:
View attachment 211688

Every peak in frequency response will cause time domain ringing which my display clear shows. I can however just change one number and get what the company shows:
View attachment 211689

Here is the company measurement:

What did I change? I moved up the bottom of the graph 4 dBSPL! This is why I say be careful with waterfall displays. It is so easy to lie with them. Or misuse them (intentionally or not).

Finally, here is the step response for fans of that:

View attachment 211690

For those of you who stop here and not read my subjective tests, I highly suggest that you make an exception and read on!

GR Research LGK 2.0 Listening Tests
I used my RME ADI-2 DAC as the source to drive a Topping PA5 which in turn powered the LGK 2.0. Listening setup was near-field.

By this time, I actually expected the speaker to sound good (based on spin data). Boy was that not the case. At any listening level above faint music, there would be this nasty warbling sound to vocals which would progressively get worse with volume. I am talking about way below the point where it crackles. The only time this was not super audible was if there was no bass at all. My female tracks are not bass heavy but the bit they had, caused this speaker distort so badly that it was unlistenable. I have tested over 200 speakers and never heard a speaker with such poor response.

By chance I had my desk lamp above it so could easily see the shadow of the driver below the cabinet. As soon as I would see any vibration in that shadow (due to the cone moving), the game was over. And again, this happened at very modest volumes with me sitting just 3 feet/1 meter away from the speaker!

Suspect bass being the problem, I took out the EQ tool and put in a sharp high pass:
View attachment 211691

This managed to get rid of significant amount of that warbling effect. But then there was so little bass that one was left thinking the sound was just too thin. That aside though, the tonality now shone through and I had little to complain about in that department. I did put a bit of the boost where that notch is and thought it improved the response subtly. To aid more in power handling I also pulled down that bass hump. This helped a bit more but now I had so little bass.

With the EQ in place, I could play at modest levels but sound was boring, and distortion still present. Unless you were playing something that as instrumental/higher in frequency range, nothing sounded clean and without distortion.

Conclusions
Ah, little giant killers... who doesn't want to see an underdog win? Put in a spokesman in front of the camera that tells the nice story and you just want to believe it. I know I believed it a lot more than what I experienced with the speaker. Yes, the tonality is good overall. No, you can't take a midrange+tweeter driver and pretend it can play bass at the same time. It simply cannot. How on earth anyone can say this speaker is usable let alone high-fi is beyond me.

Is Danny this oblivious to distortion? This is not subtle stuff folks. Measurements show extreme amount of distortion and listening tests easily bring out the same. And of course physics solidly predicts it as well.

There is a reason my acoustic measurements from day one have included distortion measurements. And why I listen for dynamic behavior in my listening tests. Hi-fi is about enjoyment and there, you want to have some volume. The LGK 2.0 simply cannot go there. The driver seems to be designed for a boombox or something with matching electronics to control what it can or cannot do. Sticking it in a box and calling it great is one of the biggest farces I have seen in audio business!

I know some may say I am biased to not like GR Research stuff. But I have given positive marks to another speaker kit of his. Importantly, I back my opinion with measurements and science/engineering of the design, not empty boasting. All the arrows point to the same thing. This speaker is simply a bad idea. Had the company spent time measuring distortion and getting feedback from others with better hearing, they would have no doubt gotten the feedback that the design was not feasible.

Yes, the tonality is good but without dynamics of any nature, it is a useless attempt.

For the same cost as these finished, you have tons and tons of choices of speakers including the aforementioned Neumann which runs over this speaker as if it is not there. I don't see the angle of "DIY" here either. Gluing a flatpack is not going to give you much satisfaction when the finished performance is this horrid. If you want to do that, build a larger speaker with proper design. This dog simply don't hunt.

Needless to say, I can't recommend the GR Research LGK 2.0. As I noted, it is the worse speaker I have heard.

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As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

You should check out Logitech's lame excuses for loudspeakers.

 

[soundintubes]

Yes he did measure distortion.

Order of magnitude lower.

Neumann KH 80 DSP Speaker Measurements: Take Two

A few weeks ago I reviewed the Neumann KH80 DSP powered monitor. The measurements while very good, did not match manufacturers published graph which showed dead flat on-axis response. Third-party measurements had shown the same so objection was raised that my measurements must be in error. I...

www.audiosciencereview.com

Please do some research first before posting these absolute statements. Maybe ask a question instead, if you don’t know. Nothing wrong with not knowing or not finding.

Thank you for this.
Although perhaps it would have been better to have provided these measurements in the first place, rather than a series of passive-aggressive denigrations.

 

[tomtoo]

Thank you for this.
Although perhaps it would have been better to have provided these measurements in the first place, rather than a series of passive-aggressive denigrations.

Just follow the kh80dsp measurements, its a nice journey. As a audio lover you should not miss. Somehow its priceless.

 

[mhardy6647]

Any attempt to commercialize anything in low volume will result in uncompetitive pricing compared to mass manufactured items.

ain't that the truth? Look at the price of the Tekton "fullrange" loudspeakers of a few years ago, or the Blumenstein Orcas, or other, similar products.
Most of these were/are just Fostex drivers in nice boxes, in many cases even sans passive networks (Zobel or BSC, e.g.). Mind you, there is cost in making a nice box, and those manufacturers are certainly entitled to a profit, but the value proposition on many of those "fullrangers" gets pretty dicey, I'd opine.

Orca 3" Wide-Band Speakers Shop— BLUMENSTEIN AUDIO

Birch Plywood : 6-8 weeks. Slightly warm yet extremely detailed Perfectly balanced for home audio. Our best selling speaker for almost 20 years In 2022, Fostex released a new version of their classic 3” driver that sounds significantly better than the older version (with the white dots o

www.blumensteinaudio.com

"From $900" (EDIT: Just to be clear, that is for a pair, not each!)

 

[mhardy6647]

Now, when Marky essays a fullranger, this is a typical result.





Didn't cost nine hundred smackers, though.

 

[HarmonicTHD]

Thank you for this.
Although perhaps it would have been better to have provided these measurements in the first place, rather than a series of passive-aggressive denigrations.

You are welcome.
You made the claim. The burden of proof lies with you, not me doing the research for your false statements.

 

[XaVierDK]

Even with the Tube Connectors???

The same guy who claims distortion doesn't matter thinks you can hear whether your wire goes straight into the speaker.
There's a point here somewhere.

 

[tomtoo]

The same guy who claims distortion doesn't matter thinks you can hear whether your wire goes straight into the speaker.
There's a point here somewhere.

Hehe tube connectors are importend, and 100 percent distortion is just a measurement artifact. Not importend for sound.

 

[Spkrdctr]

My only question is how much No REZ was included in the kit? Tube connectors, check, high end crossover, check, $10 driver, check, very nice cabinet by Rick, check, fancy internal wires with audio perfect colors, check, but wait, where is the "No REZ"?

 

[Multicore]

It makes no sense to compare a kh80dsp to this speaker. Its like comparing a lilienthal glider to a f16. When the only thing to compare them is the price.

The are also both loudspeakers. And similar size. What's nonsensical about comparing loudspeakers of similar price and size? It's what people do when they are in the market for loudspeakers.

 

[ta240]

It makes no sense to compare a kh80dsp to this speaker. Its like comparing a lilienthal glider to a f16. When the only thing to compare them is the price.

actually, it would be more like comparing a modern glider to an F16 when they are priced the same and asking why.

 

[amirm]

My only question is how much No REZ was included in the kit? Tube connectors, check, high end crossover, check, $10 driver, check, very nice cabinet by Rick, check, fancy internal wires with audio perfect colors, check, but wait, where is the "No REZ"?

As far as I know, nothing was supplied and Rick had to put in padding in there himself.