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After setting all necessary basic functions and parameters with the control software from our laptop, we switched over to the remote. For digital we used our PS Audio PWT transport via balanced connection directly into the LS1 master. After a final check, first the subs and subsequently the LS1 units powered up. Our initial setup geometry of the speakers was as per Eelco’s recommendation for the 45° toe-in and its concomitant software settings. From the listening chair this admittedly looked quite strange and counter-intuitive. Years of conditioning had formed a mind set that a loudspeaker should stare you directly in the face unless there’s something acoustically wrong or there isn’t sufficient space to move the listening chair back. Now there was nothing wrong, there was enough space but this design meant to block out room interferences as much as possible. Would it work?


After a handful of CDs we had a good baseline on what these speakers could do. At this point the sound for us was still a bit restrained in the lower mids and lowest bass. With the available software we quickly added 2dB to the Peerless-fitted subwoofer. We also placed some Blue Horizon isolation footers between the sub’s bottom and the base plate because vibrations from the subwoofer in our opinion transferred too much into the legs of the LS1. After these little adjustments the sessions continued.

The overall sound was more complete now and we noticed that the display on the wired remote showed a healthy minus 16dB. With several CDs we reached even higher levels (around 96dB on the Radio Shack SLM at the listening chair) yet the LS1/LS1s combination didn’t falter in the least. The sound was clean, dynamic and fast. Admitted we played in a large space so chances of overloading the room were pretty slim. We already mentioned the white LED mounted in the baffle forming the dot on the Grimm logo’s ‘i’. At times this LED would blink and do so not at high but normal levels. For context, normal serious listening for us equates to 85dB. Eelco explained that there are three limiters built into the firmware. These are triggered by a) driver excursion and can be switched off in software, b) clipping and c) when an amplifier exceeds a set operational temperature. These protection measures assure that the LS1 won’t be overdriven or clipped. When one of these critical conditions arises, the LED momentarily switches off. A future firmware upgrade will offer the option to turn this indication off yet not the protection. This LED indication didn’t merely indicate that the LS1 was about to clip and that the software prevented it. This LED indication also implied that other speakers are clipping happily without any such indication. That we could play the LS1/LS1s to such high SPL in a 100m² space without distortion demonstrated their true monitor quality. [Eelco added that the volume setting displayed by their remote is not relative to the standard 0dBFS but that the software has a provision to reset these values.]


Another monitor feature involving the white LED was a show & tell of mastering damage which a recording has fallen victim to. Here we refer to the practice of dynamic compression. Far too many modern releases suffer it. Even with music we die for, the difference between RMS and crest factor values is limited to a handful of dBs. Fortunately classical music recordings suffer far less from this very despicable practice. On some of these recordings the LS1 showed that internal protection was active even during moderate volumes. Dynamically mutilated recordings however would play at a higher volumes without triggering the LED as there was no actual clipping.

30° toe-in

After listening to purer more near-field signal and thus less loudspeaker/room interaction, we tried the 30° toe-in. This software change was accompanied by physical speaker repositioning. Now the room definitely had more to say. As a result from the added reflections, the music now was bigger. From this a discussion arose about what one means to hear. Is it the pure data encoded on the LP, CD or another source? Or is it about how the recording interacts with one’s own acoustic? With the latter there can be more drive, more grandeur and more more in general yet none of that was actually recorded. Those who want to temper the room’s influence are usually inclined to put up (with) all kinds of damping materials to achieve a domestic version of a semi-anechoic chamber whilst killing the speaker's sound in turn. A to us more favorable alternative is tuning a room’s limiting qualities à la Franck Tchang resonators.


Besides their room’s unavoidable influence on the playback, audiophiles manipulate the perceived sound to their personal bias(!) with all manner of matching or mismatched electronics, cables, accessories, potions and voodoo. In all cases the music heard in the room is not 100% what was recorded. Too many parameters have shifted along the way. Is this bad? Far from it. Unlike the recording arts (should be), audiophilia is a hobby not science. The ultimate musical experience will always be the live concert where imaging, soundstaging, background noise, dynamics, frequency extension, crossovers and other audiophile concerns or realities are either non-existent, different or unimportant.

45° toe-in

All things considered, we reverted to the 45° array where the LS1/LS1s combo suited us best. Contrary to popular belief, the wider sweet spot did not act like a harmonic distortion generator. Inter-channel phase/time data delivered correctly to a much wider space than thought possible became a matter of proper DSP involvement. The such widened sweet spot was suitable for two listeners. Three might have had to cozy up too much. Now we had a variety of music pass through the system. From lightning-fast flamenco to warm cello-fused tango, from intimate piano trio to brawny big bands, even electronic forces live on stage or from the dub and dance studio added their contributions. Except for the most extreme examples in the latter department, the LS1/LS1s had no issues with conveying the music, its tonality, dynamics and emotional content to the listener.


Taking the Grimm LS1/LS1s out of the studio and into the living room of course was a big and daring step. The fully active DSP-controlled concept rules out almost all audiophile/hobbyist influences, leaving only the input source, subwoofer level and crossover point plus overall volume as tweakable/tunable. This might as well be the death blow to our eternal quest for audio perfection because any such quest ends whenever a grail is found. Mind you, we used ‘a’ and not ‘the’ grail as our kind always needs an open escape route. With the Grimm LS1/LS1s the user buys a complete and finely tuned system as an off-the-shelf fully tuned music maker. Unpack the system, set it up in the living room where it will blend in perfectly, run just a few cables (and cover them nicely out of sight), place your sources next to you with the remote, invite another music lover on the sofa, hit play and get one with the music as intended.


Using modest DSP to eliminate driver tolerances combined with active tri-amping eliminates mismatches—and the usual ones are legion—by design. Driver integration is seamless and for such a three-way very rare to find elsewhere. Refraining from wireless and using pro cables also ticks off another common danger on the music-only list. Not unimportant is the use of Ncore class D amplifiers. With their switching power supplies, they are very energy efficient, even green. Keen-eyed readers will have spotted the marking on the photo of the electronics module presented earlier. It seems that amplifier is a UcD model but the truth is different. For the current LS1 builds, Bruno converted a preexisting UcD PCB to accept Ncore technology. This conversion is not available elsewhere and future LS1 modules will use ‘pure’ Ncore boards.


After living with a complete turn-key LS1/LS1s system for a while, the obvious question to be answered was, what might we do when faced with the actual prospect of buying ourselves a new sound system. Would we consider this route? In our lives music comes first, gear later. On that basis our answer would be a definite yes. With a Grimm system all the permanent unrest that comes with the hobby goes on hold. A great substitute for the terminal hardware anxiety becomes an equally obsessive hunt for software, be it CDs, LPs or DLs (downloads) from all over. We do think however that any room the LS1/LS1s gets to live in permanently should match the size of the ‘bubble’. In our unusually large 100m² room, the bubble was a bit small and one sat somewhat forlorn in space. The average living room in Holland is around 30sqm however and that would be perfect for the LS1/LS1s. If the model name is any indication, a bigger XS or XL model could be just around the corner for those more palatially blessed.
Condition of component received:  Excellent for a demo model on tour.
Quality of owner's manual: Excellent, lots of photos and with a real guide to the system.
Reusability of packing: The very large single box for both speakers is reusable several times but storage requirements make discarding of the box more likely. Separate boxes per speaker would be easier to accommodate.
Website comments: Plenty of information on products and backgrounds for pro and consumer use.
Completeness of delivery: Perfect. Included USB/MIDI interface, wired multi-purpose remote, Grimm cable package.
Pricing: Previous pricing was based on the pro version of the LS1. The consumer version includes quality lacquered bamboo veneers or white Corian cabinets, thick base plates, a USB interface and the multi-function remote.
Human interactions: Exemplary.
Remark: In the audiophile arena the LS1/LS1s operates in a class of one. For those looking after the exact sound of a recording, the Grimm solution cannot be beat. For the asking price one gets a 'guaranteed' system with minimal tweakability and no guess work. Music played is what it is, not ‘photoshopped’, beautified or compromised. Think of it as your personal home studio for playback rather than recording purposes.

Grimm Audio website