GRIMM Audio LS1c & SB1 DSP Speaker Review

[thewas]

What's the difference between LS1C and this model? View attachment 452255

The differences are written here https://www.grimmaudio.com/hifi-products/loudspeakers/ls1c/

The LS1c is the flagship of our LS1 active loudspeaker series. It is named after the revolutionary TPCD Carbon Composite tweeter that we developed in cooperation with driver manufacturer Seas. Even more important is that we rebuilt all elements of the LS1 design from the ground up: the electronics with latest generation amplifiers, the audio DSP code, the computer aided calibration method, the firmware and the PC/Mac software that controls the entire system. To pick just one example, with the knowledge we gained from developing the MU1 and MU2 FPGA Pure Nyquist filters, we were able to dramatically improve the crossover phase correction filters of the LS1c’s DSP.

As result, the LS1c offers an incredible level of integration over the full frequency band – a loudspeaker has never sounded so much ‘as one’. Its rendering of the stereo image appears more tactile than ever, its capability for microdynamics exposes unheard details and its extraordinary phase coherency reveals the subtlest rhythmic structures. At the same time the natural, non-fatiguing sound of the LS1c invites one to long listening sessions.

At the low end of the frequency spectrum, the elegant Digital Motional Feedback SB1 subwoofer offers unparalleled bass. Our unique motion feedback technology lowers the distortion by 30 dB and places the resonance frequency below 20 Hz. Bass has never sounded so detailed and controlled.

 

[feitaishi]

If you're paying car prices for speakers, you want them to get it right all the way to 15 hz. YOu don't want to have to do it yourself.

If I'm paying car prices, then I don't care spend more money on one more sub. you got to do it yourself for the best sub location in the room.

 

[Davey]

The performance below 100 hz, in volume and in distortion, kills otherwise perfect speakers. Triple the volume of that sub, port, and then match them, and you'll have appropriate performance. Even then, it will be overpriced, but at least it will be perfect.

A 10" driver in a small sealed box has obvious limitations. It doesn't matter how much equalization or servo-control you have.
In this instance though, the bass SB1 SPL capability seems pretty much commensurate with the rest of the system. I think for most users, it will probably play loud enough and low enough.

 

[DanielT]

why not add another sub on the top of this system(LS1c + SB1) and cross around 40hz?

Sure, and why not go all the way and make a three-way speaker? The physical space under the speaker is there, as I pointed out in #56.

Something like:


Minus the baffle shape. Keep the GRIMM Audio LS1c shape, which I think is nice and probably also functional. Mostly just to show an example that I took that picture. Taken at random, too, I know nothing about the speakers in the picture.

 

[beefkabob]

A 10" driver in a small sealed box has obvious limitations. It doesn't matter how much equalization or servo-control you have.
In this instance though, the bass SB1 SPL capability seems pretty much commensurate with the rest of the system. I think for most users, it will probably play loud enough and low enough.

If it played loud enough and low enough, it would not be so distorted at low frequencies, and not drop off so much. Even as the room raises the bass, there will still be all that distortion. I find it completely unacceptable. The speakers are magnificent, sure, but again, stupidly overpriced. I just don't see the value here. It's a fantastic job left utterly incomplete. They should be ashamed.

And there's no reason to make sealed subs or make sealed subs this small. It's like they handed off the sub to the junior engineer.

 

[Pearljam5000]

Great speakers I just don't understand why not just get 8361 instead and save some $$$
Obviously they don't come with subs but still

 

[Hayabusa]

If it played loud enough and low enough, it would not be so distorted at low frequencies, and not drop off so much. Even as the room raises the bass, there will still be all that distortion. I find it completely unacceptable. The speakers are magnificent, sure, but again, stupidly overpriced. I just don't see the value here. It's a fantastic job left utterly incomplete. They should be ashamed.

And there's no reason to make sealed subs or make sealed subs this small. It's like they handed off the sub to the junior engineer.

Indeed something is wrong here, This sub should be playing down to 20Hz with low distortion,,

 

[phoenixdogfan]

Personally, I choke at the price point: It's downright Wilsonesque. And then there is the issue of the bass roll off. Granted it's anechoic, and there would undoubtedly be room gain, but would the room gain be sufficient to make in room response flat to, say, even 25 hz at 90 db? I don't think so. Kef Ref speakers also have roll offs, but they're nowhere this severe, yet almost all of them except the Blades need subs. So it seems like these would need a sub on top of the existing sub, which would definitely add to the expense and diminish the purity of the concept.

And, just as importantly, they seem to have a great deal of distortion in the bass, despite their claim of having a "motional feedback technology" that "reduces distortion by 30 db." Any number of times I've heard that the distortion levels of my LS 50 Metas in the bass are something of a deal breaker, and I don't know that the Grimm's have lower levels of distortion at those frequencies than that $1000 speaker. So, it looks like there would be a definite ceiling on how loud these speakers can play and how low they could go. And except for the wide dispersion pattern, doesn't something like the Kef LS 60's have a similar performance envelope at one tenth the price if you buy "scratch and dent" (for $4000) at Crutchfield?

Maybe, for some, the whole will be greater than the sum of the parts, but frankly given the near cult-like status of these speakers, they seem like something of a disappointment to me.

In any case, thank you for the excellent review, Amir.

 

[MattHooper]

This was awesome Amir!

I enjoyed the combination of, as usual, super high-quality measurements, as well as your listening impressions.

I’m usually not excited by active speakers, but the Grimm have had my attention for quite a while. I like the look of the design with the wider baffle, and I also seem to like loudspeakers that employe SEAS drivers - both my Joseph and Hales speakers use SEAS Excel drivers and both brands have always struck me as sounding particularly clean and pure, and both seem to measure very clean in the waterfall plots as well for whatever that’s worth.

So I guess part of my initial attraction was the Grimm’s wide baffle design (something I’ve been enjoying in other speakers) combined with that big SEAS driver… and then the measurements in Stereophile wowed me.
And yours confirm them as well.

Holy cow that waterfall plot!

 

[Davey]

If it played loud enough and low enough, it would not be so distorted at low frequencies, and not drop off so much. Even as the room raises the bass, there will still be all that distortion. I find it completely unacceptable. The speakers are magnificent, sure, but again, stupidly overpriced. I just don't see the value here. It's a fantastic job left utterly incomplete. They should be ashamed.

And there's no reason to make sealed subs or make sealed subs this small. It's like they handed off the sub to the junior engineer.

Yeah, I don't disagree with you. It's certainly the weak link in this system.
But, every speaker system has a weakest link. In most cases, I'd be comfortable with bass extension and capability being that weak link.

 

[EERecordist]

It is a welcome move a high end-positioned manufacturer has submitted a speaker to be tested. They might be a good mastering studio monitor and many mastering studios spend on expensive monitors.

It appears they did a very good job on the electronics design, user experience, and industrial design. The SB1 and predecessor are motion feedback designs. Doing a little research, one reviewer termed the speaker system salonfähig which could substitute on ASR for WAF.

 

[Sokel]

Ok, mystery solved.
Everything is completely configurable and bass reaches 20Hz, linear as they say:

(link)

It's all about its settings which is not straightforward and the sample Amir got was probably not configured this way.

(reason search all this is that I have listened to it, and clearly goes low. And I'm talking 3-way low, not 2-way and sub low which is completely different)

 

[kyuu]

It's all about its settings which is not straightforward and the sample Amir got was probably not configured this way.

(reason search all this is that I have listened to it, and clearly goes low. And I'm talking 3-way low, not 2-way and sub low which is completely different)

That honestly doesn't make sense to me. One, why wouldn't they send the speaker system pre-configured to provide the best performance? Or at least provide Amir with instructions to configure it properly? Two, using DSP to make it go lower can only exacerbate the distortion issues in the bass. There's obviously some sophisticated DSP at play here and I'm sure the little sub unit is very well integrated, but it's still a small, sealed, heavily-DSP'd sub in the end and that kind of setup quickly runs into limits. Asides from the integration with the mains, you could likely get better performance from something like a Kef KC92, nevermind a "proper" sub.

 

[beefkabob]

Yeah, I don't disagree with you. It's certainly the weak link in this system.
But, every speaker system has a weakest link. In most cases, I'd be comfortable with bass extension and capability being that weak link.

Bass extension is vital to me. Every digital music recording that I've checked has significant information down to 20hz across several genres. Even pianos go to 27.5hz. I just find their subs to be unacceptable. I suppose if you could control eight of them it would be fine.

 

[Sokel]

That honestly doesn't make sense to me. One, why wouldn't they send the speaker system pre-configured to provide the best performance? Or at least provide Amir with instructions to configure it properly? Two, using DSP to make it go lower can only exacerbate the distortion issues in the bass. There's obviously some sophisticated DSP at play here and I'm sure the little sub unit is very well integrated, but it's still a small, sealed, heavily-DSP'd sub in the end and that kind of setup quickly runs into limits. Asides from the integration with the mains, you could likely get better performance from something like a Kef KC92, nevermind a "proper" sub.

I wrote it back in the thread, we're talking about a two-small-box system here, no one expects cutting-breath chest punch here.
But talking about the LF extension alone Amir's chart shows it's not configured to use the sub properly.

If I'm not mistaken they state something like 95dB SPL (both subs) down there.
I would say adequate for a small room.

 

[totti1965]

Surprisingly in terms of Distortions, the Neuman KH 150 is still the undisputed King...... for just 1/10 of the price!

 

[kyuu]

Even pianos go to 27.5hz.

Ugh, I dislike when this talking point is brought up. As someone who plays piano, I can assure you that most piano repertoire does not use the lowest A. Further, the bass strings for the lowest notes on all but the largest of concert pianos have so much harmonics that you hear those more than the fundamental.

Still, at this price point I don't think it's unreasonable to expect this speaker to be able to cover down to 20Hz competently considering there is vastly cheaper equipment that can do so.

 

[kyuu]

I wrote it back in the thread, we're talking about a two-small-box system here, no one expects cutting-breath chest punch here.

Considering the price, I sure as heck would expect it to be able to handle high SPLs competently. If they needed to add more/bigger/better drivers, there was certainly room in the budget and the build.

But talking about the LF extension alone Amir's chart shows it's not configured to use the sub properly.

Again, the company sent it and if they didn't configure it properly or provide Amir directions on how to do so, that's on them. Amir also stated that he contacted the company to see if they saw any problems with the results, and they either did not or did not care to respond.

 

[Heinrich]

Two, using DSP to make it go lower can only exacerbate the distortion issues in ...

Imagine uncle Paul comes for a visit, and while talking, w/o looking, mindlessly sets his coffee cup on the sub's grille ... doggy Willi will have a great time to run over and through likewise. Not that practical as a design element after all. And, you cannot optimise the position either.

What is excaberated, in my book at least, is the lifestyle appeal. A DIYer could replicate the design, from a technical point of view all virtues, soundwise, maintained, with ease. I did it myself long before Grimm came up w/ the first LS. It was so much of an Aha effect, that I, for a millisecond, thought they stole it - of course that wasn't true.

Is it beautiful? Only as much as you are into speakers for themselves. It will catch attention, but also dust, especially if there's a good ol' real carpet in place. who is going to educate the housekeeper on 'do not touch here, but there' and so forth.

 

[Sokel]

Again, the company sent it and if they didn't configure it properly or provide Amir directions on how to do so, that's on them.

Of course is on them!
Even if they assumed that Amir would go through all the lengthy configuration that's also wrong.
At this price tag the norm is for the rep to configure it for you and up to your taste.

It's not like some DIY 2-way and subs looking to YT to integrate it and have 100 pages threads at ASR for the optimal way.