GR Research LGK 2.0 Speaker Review (A Joke)

[voodooless]

Well, that was fun

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 said, this thing would benefit from something like a 6.5” or 8” woofer crossover at somewhere around 500 Hz. Since the driver is only $40, that leaves plenty of budget if you don’t go for the kit option. Then again, a low fs tweeter with a waveguide will probably do better in that case.

The tiny KH80DSP will do only a bit better in the distortion part. I guess it also handles the breakdown it much more gracefully.

See here its distortion boundary. It very much tracks with what we see here. There is probably 6 to 10dB more oomph in it compared to the GR. Obviously it’s a far better speaker overall. 10 dB amounts to about double the perceived loudness, so will be quite noticeable.

 

[abdo123]

This might be a good chance (or a motivation) to dig and see whether Klippel have a developed a standard of measuring inter modulation distortion.

The regular harmonic distortion measurements don’t really indicate that speaker is absolutely unusable. Small sure, but unusable not really. But when you consider that it’s one diaphragm playing everything I wouldn’t be surprised with the warbling sound tbh.

 

[FeddyLost]

The break-up and dispersion of the driver look surprisingly good.

Just due to beefy notch filter. Otherwise it wouldn't be so pleasant.

 

[mightycicadalord]

Worth noting the flatpacks don't look to have a roundover on the baffle. Better have a router and a nice bit.

 

[abdo123]

Well, that was fun

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 best guess is that the real Xmax is just around 1mm. The reflex tuning only can do so much to extend the inevitable…

That said, this thing would benefit from something like 6.5” or 8” woofer crossover at somewhere around 500 Hz. Since the driver is only $40, that leaves plenty of budget if you don’t go for the kit option. Then again, a low fs tweeter with a waveguide will probably do better in that case.

The tiny KH80DSP will do only a bit better in the distortion part. I guess it also handles the breakdown it much more gracefully.
View attachment 211741
See here it’s distortion boundary. It very much tracks with what we see here. There is probably 6 to 10dB more oomph in it compare to the GR. Obviously it’s a far better speaker overall. 10 dB amounts to about double the perceived loudness, so will be quite noticeable.

By the way at the limit of Xmax you’re expecting 10% THD, so hardly Hi-Fi at 80dB.

 

[tomtoo]

Finished the same expensive as a kh80dsp?
Come on, thats crazy overpriced.

 

[Lopsided]

With 2.5mm of apparent Xmax you should get about 86 dB at 100 Hz/1m

How to convert xmax to spl?

 

[voodooless]

By the way at the limit of Xmax you’re expecting 10% THD, so hardly Hi-Fi at 80dB.

Yes, 1mm at 200 Hz gives you 90dB. Coincidentally that is about what it shows in @amirm’s graphs.

 

[voodooless]

How to convert xmax to spl?

By the sheer power of math… or if you’re lazy like me, an online calculator.

 

[DanielT]

Thanks Amir, good job. Consumer information at its best!

Amir:
"The main driver is a tiny" full range "3 inch unit"

I say what others have either already said or will say. Use it as a midrange in a three-way construction. It still can not handle lower bass frequencies. Then a proper tweeter instead at the top. Even a DIY beginner understands that. But at that price? Nop. Here, on the other hand, is a well-known and really affordable 3.5 driver:

Peerless TC9FD18-08 | HiFiCompass

The THD measurements at voltage level 2.83 Volt were carried out with High Pass Filter "on" (2nd order Butterworth type, 80 Hz cutoff, HPF2-80) The THD measurements at voltage level 4 - 11.2 Volt were carried out with High Pass Filter "on" (2nd order Butterworth type, 150 Hz cutoff, HPF2-150)...

hificompass.com

You can usually get it for around $ 20.

 

[test1223]

Is this the driver in the kit?

https://www.oaudio.de/en/speaker-diy/omnes-audio/wide-rang/omnes-audio-bb-3-5.html

38.80€

 

[respice finem]

I think the why is clear: selling $300 worth of crossover parts for a $40 driver! All it needs to be believable is to claim it performs better than larger speakers.....

While we're at it: The comparison with the KH80DSP is interesting, because it has

• amplification included (bi-amping)
• DSP crossover, with the option to "cooperate" with its matching subwoofer. With this, it becomes a 3-way system, which can very well compete with larger (and more expensive) speakers. Yes I did listen to it
  
• a rationally (form follows function) designed waveguide and cabinet
• XLR in = forget connection woes
• integrated protection for the drivers, both mechanically (mesh) and electronically (limiter).

Ceterum censeo: Hard times for those "spreading the gospel"

 

[Ageve]

There is no crossover filter.... just a passive EQ circuit.

Hehe I know. But there are ”crossover”components included (for the EQ circuit).

Speaking of distortion, he once told me (in a Youtube comment) that it’s just a catch phrase, and it’s not audible. I guess/hope he didn’t mean this speaker.

 

[voodooless]

Is this the driver in the kit?

https://www.oaudio.de/en/speaker-diy/omnes-audio/wide-rang/omnes-audio-bb-3-5.html

38.80€

Nope, parameters are not the same, nor is the magnet material and esthetics.

LGK 2.0 Woofer | GR-Research

gr-research.com

 

[eddy555]

well stop and think for a minute - it's a 3 inch passive full range driver doing on par or even better in terms of linearity than many 3 way dsp driven monitors...I mean it has to give up on something...in this case the trade off is higher distortion.

 

[beeface]

Danny, is that you?

 

[respice finem]

well stop and think for a minute - it's a 3 inch passive full range driver doing on par or even better in terms of linearity than many 3 way dsp driven monitors...I mean it has to give up on something...in this case the trade off is higher distortion.

Which and how many "3-way DSP driven monitors"?

 

[DanielT]

What sort of "giant" is this vastly overpriced thing supposed to kill?

Bad sound kills good music.

 

[Robbo99999]

Jesus, so for everything below 80Hz you're essentially listening to just distortion?!

 

[thewas]

The tiny KH80DSP will do only a bit better in the distortion part. I guess it also handles the breakdown it much more gracefully.

See here it’s distortion boundary. It very much tracks with what we see here. There is probably 6 to 10dB more oomph in it compare to the GR. Obviously it’s a far better speaker overall. 10 dB amounts to about double the perceived loudness, so will be quite noticeable.

Harmonic distortion is anyway unfortunately not a great metric to correlate with audibility, would be more interesting to compare the intermodulation distortion of both where the 2-way KH80 would be also superior, see also

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.

Those are all signs of high IMDs.