RBH Sound Signature 61-SFM/R Floor-Standing Loudspeaker Review

RBH Sound 61-SFM/R Modular Tower Speaker Introduction

It’s strange to think that modular designs aren’t more popular with tower speakers. They are easier to deal with, logistically; instead of a single large unit that requires heavy-duty packing, the speaker is packed in two boxes which makes it less prone to shipping damage. Modular designs have inherent construction advantages that single-piece towers don’t necessarily have; bracing and woofer compartment separation is built-in with modular systems. They can also simplify design where the internal space required by the drivers are more easily designed for and accommodated. These aspects make it easier for them to be a better loudspeaker.

It could be argued that a subwoofer/satellite system is essentially the same thing, and that would be kind of true in instances where people stack the satellite speakers on top of subs, but that isn’t often the case. Subwoofers usually have a much larger footprint than tower speakers, and the crossover between the speaker and sub is never truly optimal since it is a generic filter set applied by the AVR. So while the blend between the sub and satellite might be a good match, it is rarely a perfect match.

RBH Sound has had dalliances with modular tower systems with good results, but usually, that type of setup was reserved for their expensive flagship systems such as the SVTRS Active Towers. However, for the 61-SFM.R Tower, the subject of today’s review, they attempt to bring modular design down to a much more affordable price point. How well have they succeeded? Let’s dig in to find out…

RBH Sound Signature 61-SFM/R Appearance

The RBH Sound 61-SFM/R has a fairly straightforward appearance. It doesn’t try to hide its boxiness with rounded corners or a curved section of the cabinet; in fact, it embraces its boxiness for a minimalist aesthetic. Its visual simplicity enables it to fit in well in a wide variety of interior designs. It can be had in a satin white or black finish, and the version I received was satin black. The satin finish is high quality, but it must be said that, as with all smooth satin blacks, fingerprints do show up easily when the surface is touched with bare hands. For this reason, I think RBH should consider including some cotton inspection gloves for the unpacking and setup of the speaker. This would be an inexpensive addition and give the unpacking experience a more deluxe feeling.

The AMT tweeter and aluminum midrange woofer are mounted flat on the front baffle. Otherwise, the front baffle is featureless except for a small RBH badge below the midrange woofer. The bass drivers are mounted on the sides of the lower section of the speaker. The bass driver cones have their own grilles that cover them on both sides of the cabinet, and the tweeter/woofer section has its own grille that hides those drive units. With grilles on, the speaker looks rather muted. Taking the grilles off does give it more personality. The 61-SFM/R is so simple in appearance that it still has a clean look without grilles, especially since the magnetically attached grilles do away with the need for grille guides to mar the front baffle. Outriggers with big spiked feet do lend it a more substantive styling. One interesting way the appearance can be changed is that the aluminum woofers can be had in either metallic or anodized black. If it were me, I would go with black cones for the satin black finish and metallic cones for the satin white finish. Overall, the 61-SFM/R has a clean, minimalist design that few people would have problems with.

RBH Sound Signature 61-SFM/R Design Analysis

Taking a broad view, the 61-SFM/R is essentially just a bookshelf speaker (the 61-SF/R in this instance) mounted on dual-opposed 8” bass drivers passive subwoofer acting as a speaker stand. This can be a very capable design if handled well, so the details matter for this loudspeaker. Let’s begin our discussion of the 61-SFM/R at the top of the frequency band with the tweeter. The tweeter is a 1” AMT. AMT tweeters can range in quality and don’t really have any visible design cues that can be used to determine how good they are. RBH Sound has had great success with AMTs in the past, so I trust that this one is good, although not every AMT from every manufacturer that has run across my path has been great.

The midrange uses an aluminum cone as so many RBH Sound speakers do. It has a solid non-ferrous metal alloy phase plug with a cast aluminum basket. The motor uses a ⅞” thick magnet with a 4” diameter and has a slightly bumped-out backplate for higher excursions. The bass drivers similarly use aluminum cones with a cast aluminum frame. They have ¾” thick by 4 ½” diameter magnets and a bumped-out backplate with cooling done through the pole piece. Two bass drivers have about the same surface area of an 11” cone, so the 61-SFM/R should have a good amount of low-frequency thump. The dual-opposed mounting of the bass drivers is a good idea here since they cancel out each other's inertia, so the bass module section of this speaker will not have any rocking motion from the moving mass of the woofers. That makes it an inert and unmoving stand for the bookshelf speaker section.

Crossover frequencies are 2.7kHz between tweeter and midrange, and 100Hz between midrange and bass drivers. I have reviewed a fair number of tower speakers recently that had unusually low crossover frequencies to the bass drivers. Low-frequency crossovers to the bass section require big inductors with high values and necessitate insertion losses. It can also be a problem when trying to integrate the speaker with a separate powered subwoofer in a multi-channel playback system with LFE. It becomes difficult to calibrate when using conventional crossover frequencies like 80Hz. The reason is that the phase rotation that occurs in the filter will make it hard to match the filtration of the sub’s low-pass filter since that will also have phase rotation. It will be difficult to properly align the sub with this speaker since the phase will be very busy at typical crossover points. It may be easier to integrate a sub by just setting the speaker to full range, although I don’t think that many buyers of this speaker will think it needs the assistance of a subwoofer, so this may be a moot point.

The 61-SF/R bookshelf speaker section doesn’t have a whole lot of crossover elements, but the elements it uses are high quality, with four large poly-film capacitors, two air-core inductors, and two beefy resistors. As with other RBH Sound speakers, we see the use of a self-resetting poly-switch which protects the tweeter by raising resistance above certain electrical current levels that would place the tweeter in danger.

RBH Sound 88-MS Bass Module Crossover

According to Shane Rich, Technical Director of RBH Sound, for the 88-MS bass module, the filters are in effect 1st order to within an octave or so of the crossover point and then transition to second order. Because the crossover is low order, the phase shift is minimal and the 8” drivers actually still have usable output beyond 200Hz, allowing for ample dynamic range. Shane claims having the lower crossover point also minimizes phase shift in the vocal region (which would be more noticeable) and is optimal for better imaging.

The wiring of the speaker is a bit more involved than typical passive speakers. Users need to attach the speaker cable to the lower pair of binding posts of the bass module section and then wire that section to the bookshelf section via the bass section’s upper binding posts. RBH provides the wires to connect the two sections together. The bass module can be made to have more or less bass depending on how it is configured. There is a single jumper on the right pair of binding posts, and if left installed, users will get an even level of bass with the bookshelf portion. Remove the binding post and the user will get increased bass output from the bass module. For a lowered bass level, users can remove the jumper and connect the positive input to the upper positive binding post. If that all sounds convoluted, RBH Sound does provide a diagram that makes it easier to follow.

The enclosure is made from ¾” high-density fiberboard. The structure is inherently well protected against cabinet vibrations since it is more like two separate speaker cabinets than a single one. The bookshelf segment of the cabinet has a window pane brace in it and lots of Dacron-type acoustic stuffing. It rests on the bass section on top of a soft material that damps vibrational transfer. The two sections are attached together with a plate that screws into the rear panels of both sections. The bass section has acoustic foam pads lining the walls. A rear-mounted slot port adds rigidity to the bass section as well as adds weight for a lower center of gravity. The 61-SFM/R uses spiked feet mounted on some outriggers. They can be individually adjusted to have a solid footing even on an uneven surface.

RBH Sound Signature 61-SFM/R Listening Sessions

In my 24’ by 13’ (approximately) listening room, I set up the speakers with a few feet of stand-off distances between the back wall and sidewall and equal distance between the speakers and the listening position. I angled the speakers to face the listening position. The listening distance from the speakers was about 9 feet. No room correction equalization was used. Processing was done by a Marantz 7705 and the amplification was done by a Monoprice Monolith 5x200 amplifier. No subwoofers were used.

Music Listening

My current infatuation for the music of Ralph Vaughan Williams has not abated, and I decided to use a high-profile recording of his work to see what the 61-SFM/R could do with orchestral music. “Job: A Masque for Dancing, Old King Cole: An Orchestral Ballet” was a best seller in the classical genre in 2023. The title indicates the works recorded, but the real highlight of this set is William’s revered ‘Job,’ often considered one of his finest achievements. It’s an expressive and vivid orchestral work that was intended to become a ballet but is much better known for William’s dramatic musical composition. This performance was conducted by Andrew Manze who has had much success with Vaughan Williams; he has released recordings of all nine of Williams’ symphonies to great acclaim. I was looking forward to seeing what the 61-SFM/R could do with this work. I streamed it from Qobuz in a 96kHz/24-bit resolution.

The first aspect of the sound that leaped out to me in this recording was the concert hall ambiance. This performance was recorded at the famed Liverpool Philharmonic Hall, and while the album is not awash in concert hall reverb, we do hear some of the acoustic character of the venue. The 61-SFM/R was able to convey this character nicely, likely on account of its wide-dispersion design where acoustic reflections from the sidewalls led to a wide, expansive soundstage. Many concert hall recordings don’t have very precise imaging, but this one could indicate fairly well-defined positions for instruments when they were playing solo, and the locations of instrumental sections came through distinctly as well. The orchestral sound had a good tonal balance, and I did not hear anything over-emphasized or softened. The overall sonic character sounded true to life. In the ballet, “Job, a Masque for Dancing,” there were wide contrasts in dynamics between the quieter, more serene passages and the more fervent passages where the orchestra was playing at full tilt, a not unexpected juxtaposition given its biblical subject. The 61-SFM/R reproduced both ends of the dynamic range with equanimity, so the crescendos were given appropriate bombast but the peaceful moments were lucid and not lost in the mix. In the end, I understood the buzz about this album in classical music circles, and I would encourage listeners to give it a try on a good pair of speakers as I had with the 61-SFM/Rs.

For something that brings a human voice to the fore, I found a terrific new album through Qobuz’s Discovery feature titled “Pearls on a String” by Katerina Pejak. This is a fairly straightforward blues album, but the recording quality is excellent. Pejak’s low-key and mellifluous voice takes center stage here, and I was surprised to learn that Pejak is Serbian; from her singing, I would have assumed she was from the American South, especially since these are all original songs written by her. She is accompanied by piano, multiple guitars, saxophone, percussion, bass, and backup singers. There is a great variety of emotional tones in this album that keep it fresh throughout its running time.

The first track, the title song of this album, is fairly lively and lets loose the piano, electric guitar, percussion, and bass, although not to the point of overshadowing Pejak’s voice. The 61-SFM/R speakers imaged the positions of all the instruments well, and they mostly occupied the middle of the stage, veering slightly left or right with Pejak’s voice anchoring dead center. On these speakers, it was easy to hear that the instruments were recorded in the near-field and then mixed for a more recessed sound as if the band were playing behind the speakers. On the third track, a plucked double bass is given prominence, and it had a full-bodied sound by the 61-SFM/Rs. The bass was able to start and stop on a dime as well, and the plucks had a quick attack with the mutes having an immediate halt. The fifth track, “Notes on Boredom,” had a terrific illustration of Pejak’s singing with a more spacious presentation of the instruments. It had a mellow but slightly sinister feel, and it was an album highlight that sounded terrific on these speakers. Throughout the album, the many instruments used as well as Pejak’s voice sounded natural and balanced, and I didn’t note anything tonally amiss. The album as a whole sounded fabulous and well worth listening to, especially with a competent sound system such as the 61-SFM/R speakers.

Taking a turn for the opposite of traditional blues, I threw on Oneohtrix Point Never‘s “Garden of Delete.” This 2015 electronic music album isn’t really classifiable within any subgenre of electronic music. It’s experimental but still has enough of a sense of melody and rhythm to find a relatable groove. The production is unlike any other, save for other Oneohtrix Point Never albums, and the artist's riotous use of studio trickery makes this a rollercoaster of an album to listen to, especially on a high-end sound system. Listeners who want to hear synthesizers and studio artifice run rampant should give “Garden of Delete” a listen. Those who queue up this album with an open mind will have a blast.

After a short intro track, the second track, “Ezra,” used bizarre samples as instrumentation along with a smattering of acoustic instruments, and it placed some precise sound elements within an overall big soundstage. The 61-SFM/R did a good job of localizing the individual sound elements within the larger soundscape, and it could project sharp imaging within a big soundstage. The track “Sticky Drama” used a very chunky synth sound as the lead instrument, and the speakers rendered it as the massive wall of sound it was intended to be (look up the official music video for this track if you want to see something entertainingly nuts). Another track that relies on a fat lead sound was “Mutant Standard,” and the 61-SFM/R gave this striking sound enough verve to make it pop. The wildly oscillating sounds on track “Child of Rage” were imaged with clarity even as they rapidly swung back and forth across the soundstage. Another mad concoction was the track “I Bit Through It” which created a traceable rhythm out of some breakneck sampling, and the 61-SFM/Rs kept it coherent and lucid despite its rapid-fire electronic instrumentation. Oneohtrix Point Never’s penchant for massive leads returned with the track “Lift,” and the speaker had no problems belting out the harmonically rich sound that was given such a whirlwind notational palette. I greatly enjoyed “Garden of Delete” on the 61-SFM/R speakers. It’s not music for everyone, but those who are looking for a wholly original sound ought to give it a chance, especially when they have higher fidelity speakers such as the ones I heard this album on.

For something to see what the 61-SFM/R could do when pressed hard, I listened to the “Cognitive” EP by 3RDKND. 3RDKND is a collaboration between drum’n’bass veterans Donny, Forbidden Society, and Katharsys, all purveyors of the harder edge of the genre. The beats, bass, and lead synths are all jacked to digital full-scale almost constantly. At high drive levels, it’s enough to push any speaker system to the brink of destruction. This is aggressive music and is meant to be played loud.

I managed to push the 61-SFM/R to the point where the midrange cones could be seen to visibly moving. At that point, I was probably approaching the limits of the speakers, but it was at a sound level so absurdly high that I doubt any normal user would push them that hard. I certainly didn’t play them that loud for long out of fear of incurring hearing damage, but I didn’t notice any audible misbehavior. Kick drums were given a meaty thump and basslines were given a palpable growl. The bass couldn’t quite match the more powerful subwoofers that I deal with that use 15” woofers or larger, but it was certainly on the level of the more potent 12”s. The tweeter was very much game for these spirited loudness levels, and the snares snapped sharply while the hats shimmered and sizzled. The 61-SFM/R can do loud music and have no problems filling my medium-sized room with heavy-duty drums and bass. I think they would be overly stressed if they were trying to charge a larger room for the same SPLs as I played them at in my 3,500 cubic foot room, but again, I doubt most people would ever drive them that loud. I think they could handle large rooms but not at extraordinary loudness levels.

Movie Watching

To see what the 61-SFM/R could do for home theater, I watched “The Beekeeper,” a new Jason Statham movie about a beekeeper whose friend is destroyed by a scam run by a powerful company. Of course, being a Statham movie, he is not just an ordinary beekeeper but is also a member of a clandestine organization of highly-trained operatives. Needless to say, he avenges his friend in a violent rampage. The plot seemed like a standard revenge action movie, but the direction of the talented David Ayer promised to lift this above the genre business-as-usual.

“The Beekeeper” turned out to be a lot more preposterous than I was expecting, but I had fun watching it nonetheless, and the 61-SFM/R complemented its energetic sound mix nicely. The action doesn’t start right away, but when it does get going, it ratchets up to absurd proportions. The action starts with the beekeeper beating up a security team and blowing up an office building, and the speakers gave the erupting building a powerful grunt. One notable scene takes place at a gas station where our hero is attacked by a six-barrelled minigun. The continuously firing gun roared on the 61-SFM/R, at least until the protagonist bonked his assailant with a jar full of honey. Much of the action was hand-to-hand combat, and speakers delivered a meaty thud for the various punches and kicks. A lot of people are thrown through glass panels in this movie, and the tweeter gave each shattering a violent crackle. Dialogue intelligibility was always good, and I was never at a loss to understand any speech. The music by Jared Micheal Fry and David Sardy was a pretty typical orchestral action score, and it was reproduced with appropriate bombast by the 61-SFM/R speakers. As I said, I enjoyed “The Beekeeper,” but it was a lot more ridiculous than the standard revenge flick that the trailer promised, and I am fine with that since there are already so many by-the-numbers revenge-based action movies. The most important aspect, the action scenes, are well-staged, and that helps me to forgive its many massive leaps in logic and plausibility. That being the case, its presentation is all the more important, and so such a movie benefits highly from a great sound system like what RBH has loaned me for this review.

A movie I had an interest in seeing was “The Last Voyage of the Demeter,” a 2023 horror film that looked like it could have a lively sound mix owing to its subject matter. Those who read the novel “Dracula” will remember the Demeter as the ship that unwittingly carried the eponymous vampire as cargo much to their misfortune. One by one, the crew gets picked off along their journey: will they realize what the threat is before they are all gone? While the movie was critically derided, I decided to give it a chance anyway owing to the cool idea. A monster creeping around a Victorian-era cargo ship was a great opportunity for some interesting sounds and imaging.

“The Last Voyage of the Demeter” turned out to be a perfectly serviceable genre entry, and it profited from having a good loudspeaker system in use. The ambient creakiness of the ship and the brush of the water against its sides would probably be best experienced in a surround sound system. However, the wide and enveloping soundstage projected by the 61-SFM/R speakers was a perfectly fine substitute, and I did not miss the surround channels at all. Some sequences took place in fierce thunderstorms; the thunder was given a subterranean rumble and the crashing waves were given a forceful boom. The dual 8” bass drivers were given a real workout, but they proved to be up to the task, and I felt no need for the addition of a subwoofer. The sounds of the creature stalking the Demeter’s crew were properly rendered, and the locational cues were well-defined, so I knew where it was without having to see it. Dialogue intelligibility was good, and I could follow the characters’ speech, even though the multinational crew had a variety of accents including Irish, Scandinavian, Romanian, and Russian. The prolific composer Bear McCreary created the music score, a dramatic if fairly traditional orchestral arrangement, and the 61-SFM/R speakers gave it a big-screen feel. “The Last Voyage of the Demeter” was a simple and direct story, and in that sense, it reminded me of older horror movies from the 1960s heyday of the British Hammer Films studio. It would have been a perfect fit in their roster of gothic horror, but I am glad that it was a contemporary release, if only as a reminder that a movie centered on a straightforward plot can still be produced. It’s worth checking out, especially for those who have a speaker system that can allow its intricate sound mix to shine such as the 61-SFM/Rs. 

RBH Sound Signature 61-SFM/R Floor-Standing Loudspeaker Measurements

The bookshelf speaker part of the RBH Sound 61-SFM/R speaker, the 61-SF/R, was measured in free air at a height of 7.5 feet at a 1-meter distance from the microphone, and the measurements were gated at an 11-millisecond delay. In this time window, some resolution is lost below 250Hz and accuracy is completely lost below 110Hz. Measurements have been smoothed at a 1/24 octave resolution. Since our frequency band of interest is well above the crossover frequency to the bass module, we opted to measure the bookshelf speaker part alone because it should measure nearly identically as the fully-assembled tower, yet the higher elevation we can give the bookshelf speaker will allow us to have better resolution down to lower frequencies.  

The above graph shows the direct-axis frequency response and other curves that describe the 61-SFM/R’s amplitude response in a number of ways. For more information about the meaning of these curves, please refer to our article Understanding Loudspeaker Measurements Part 1. The measurements presented by the speaker are overall good. There are some minor ripples across the on-axis response that are mostly due to baffle reflection and diffraction since we don’t see them on the early-reflections curve, and the nature of those qualities are inherently less audible than if they were resonances, not that they would be majorly audible attributes even if they were resonances. The listening window curve and early reflections curve stay within a fairly tight +/-2dB window until very high treble frequencies which do not matter as much. Those metrics are the chief determinants of sound character, and that denotes a fairly neutral sound for this speaker. 

The above graphs depict the speaker’s lateral responses out to 90 degrees in five-degree increments. More information about how to interpret these graphs can be read in this article: Understanding Loudspeaker Review Measurements Part II. In these graphs, we get a closer look at the lateral behavior of the 61-SFM/R. The off-axis responses correlate pretty closely with the on-axis response with a few small exceptions. That means that this speaker should sound very similar over a broad area. Higher frequencies do attenuate a bit as we move off-axis, so those who want a warmer sound merely have to angle the speakers outward to face a parallel direction. That should put the listener within a 20 to 30-degree angle where frequencies above 4kHz are shelved a bit. Above 10kHz, the tweeter does start to narrow its dispersion, and users who want to be met with very high treble should have the speaker roughly face the listener.

The above polar map graphs show the same information that the preceding graphs do, but they depict it in a way that can offer new insight regarding these speakers’ behavior. Instead of using individual raised lines to illustrate amplitude, these polar maps use color to portray amplitude, and this allows the use of a purely angle/frequency axis perspective. The advantage of these graphs is that they can let us see broader trends in the speaker’s behavior more easily. For more information about the meaning of these graphs, we again refer the reader to Understanding Loudspeaker Review Measurements Part II.

In this graph, we can see that the 61-SFM/R has a fairly wide dispersion overall, and listeners will be hit with a full sound all the way up to 10kHz out to a 60-degree angle. These speakers offer good coverage over a broad area. We do see some slight waist-banding around the 2kHz region where the woofer is beginning to constrict its dispersion, but as the tweeter takes over, the dispersion pattern widens up a bit more. This is a fairly mild directivity mismatch between the tweeter and woofer and is pretty commonly seen with 1” tweeters (dome or AMT) when paired with a 6.5” woofer. It’s not going to result in any major coloration in sound and is worth noting more for academic curiosity rather than any audible consequence. This mismatch might have been solved by using a 5.25” or smaller woofer but that would sacrifice dynamic range, and the lessened dynamic range is more likely to interfere with the sound than a mild directivity mismatch. Something else to note is the tightening dispersion above 10kHz; while AMT tweeters can have this effect, it is much milder than dome tweeters, so this constriction of output would have been more severe if RBH had used a typical dome tweeter.  

The above graph shows the 61-SFM/R’s response behavior along its vertical axis where zero degrees is directly in front of the tweeter, negative degree values are below the tweeter, and positive degree values are above the tweeter. This speaker doesn’t allow for a whole lot of vertical movement before the woofer starts to fight with the tweeter, so we get about +/-5 degrees of vertical angle before crossover nulls kick in. Listeners should ensure their ears are at or near the tweeter’s height. That is true for most speakers, but it is especially true for these. It shouldn’t be a problem since the tweeters have about a 41” height which brings them up to an approximate ear level of most listening positions.

The above graphs show the 88-MS low-frequency responses that I captured using groundplane measurements (where the speaker and microphone are on the ground in a wide-open area). The MS-88 is the name of the bass module used in the 61-SFM/R. It should be noted that given the distances and crossover frequencies between the midrange driver, bass drivers, and port location, this is not an easy loudspeaker to get an accurate low-frequency response, and the port’s contribution is probably underrepresented. That being said, we can still get an idea of the extension of the 61-SFM/R. Port tuning seems to be around 30Hz; indeed, in my listening room, I could get a strong response down to 30Hz but not much below that range. The system looks to have a small bump at around 100Hz, but I didn’t notice any bass particularly thick in that range. The port is possibly a bit underdamped, but most people’s room gain will shore up lower frequencies to be on par with the mid-bass levels. This is a strategy for an even bass sound used in many floor-standing loudspeakers, and it is a sensible one. My own listening room, which does not benefit from a lot of room gain, still overboosts the bass in loudspeakers that have a flat response down to low frequencies. The bass module allows the user to change bass levels by the presence of a jumper on the positive terminals, but I found that it only changed output by about 2dB.

The above graph shows the electrical behavior of the 61-SFM/R speakers. RBH Sound specifies this as a 6-ohm nominal speaker, and that is correct.  This is a relatively benign electrical load for nearly any amplifier. One notable attribute we can see is how far down in frequency the lower peak in the low-frequency saddle. This is a result of the very low tuning of the port, and we can see from the minima of the saddle that enclosure tuning is about 30Hz. There is not much else unusual to note here, despite how unusual the design is as a whole.

RBH Sound Signature 61-SFM/R Floor-Standing Loudspeaker Conclusion

Before bringing this review to a close, I will briefly go over the strengths and weaknesses of the product under evaluation, and, as always, I will start with the weaknesses. The 61-SFM/R doesn’t have many weaknesses, but one potential shortcoming for some buyers would be how unusual the speaker is to set up as a whole. This may not be a problem for those who choose to have dealers set the 61-SFM/Rs for them, but the wiring situation is not intuitive for people used to typical loudspeakers. The single jumper on the bass module’s positive terminals that can be used to attenuate the bass module levels would certainly be a curveball for those who don’t follow the user manual.

Another caveat that comes with the 61-SFM/R is how the bass module would play with any subwoofers in use. I strongly recommend that users who wish to add subwoofers use the 61-SFM/Rs as full-range loudspeakers and calibrate the subs accordingly. Many people typically bass manage their main speakers by high-pass filtering them from subwoofers. However, the bass module on the 61-SFM/R should be thought of as a subwoofer itself, albeit a passive one. With the 61-SFM/R’s passive 100Hz low-pass filter, there would be appreciable phase rotation at any typical subwoofer crossover frequency that it could be very messy to try and integrate subs with these speakers using a high-pass filter. Besides, the whole point of these speakers is to have left and right fronts that can play full range, so high-pass filtering them to a sub defeats their reason for existing. Set the 61-SFM/Rs to be used as full-range speakers, with or without a subwoofer.

That brings me to another point which isn’t a pro or a con but rather an observation about whom these speakers are best suited for. With the prevalence of subwoofers these days, the 61-SFM/R is a bit of an odd duck since the bookshelf portion, the 61-SF/R, is a perfectly fine speaker in its own right and does most of the heavy lifting in this modular tower system. So the tower speaker variant that is the subject of this review, the 61-SFM/R, only extends the bass response while placing the 61-SF/R on a stand that makes it look like a single-piece tower speaker. However, that adds quite a price premium over the 61-SF/R bookshelf portion that retails for $2.4k/pair. Those who are going to integrate subwoofers into their system can skip the bass module and just get the 61-SF/R without much of a penalty in sound quality. The addition of the bass modules along with subwoofers can potentially help address room modes for a smoother in-room response, but the added cost is not insignificant. In my eyes, that makes the 61-SFM/R a somewhat niche item as a whole. If you don’t need the clean looks or small footprint of the 61-SFM/R, you can achieve the same effect and potentially with greater dynamic range and lower-frequency extension by just placing the 61-SF/R bookshelf speakers on a pair of subwoofers. That would make bass management a lot simpler and give the user a system with a more potent low-frequency response. Of course, it would look a bit more ungainly than the 61-SFM/R tower speaker as a whole, and that is the tradeoff.  

RBH Sound 61-SFM/R Superb Sound Quality & Bass Extension

Let’s now turn our discussion toward the 61-SFM/R’s strengths, the foremost of which is their sound quality. They turn in a neutral and even sound that doesn’t over-emphasize or de-emphasize any particular frequency range. Their off-axis coverage doesn’t change that neutrality either, so they retain a balanced sound over a wide listening area. Their imaging was superb, and they could localize sound sources with a high level of precision, even within a wide and expansive soundstage. The dynamic range was also very good, and these could get louder than I could bear at a 9-foot listening distance without running into any audible distortion or compression. The 61-SFM/Rs have great low-frequency extension and could dig to just below 30Hz in my room with authority. They are full-range speakers and do not need the help of subwoofers to reproduce deep bass.

Another of the 61-SFM/R’s strengths is their build quality; they are a fairly solid speaker set with plenty of bracing, internal damping, and HDF construction. The drivers and crossover components are of high quality. The finish has a real satin luster and is not a vinyl wrap like some of its competitors. The speaker looks nice and would not visually conflict with a wide range of household interior design on account of its minimalist styling. In this regard, another plus is that it is a true full-range tower speaker that isn’t huge or inordinately heavy. Most tower speakers of its size do not attempt to reach into such deep frequencies

Something else that might appeal to some buyers in North America is that the 61-SFM/Rs are largely made in the USA. The enclosure and assembly happen in Utah. Very few other loudspeakers in this segment are made outside of China.

In the end, I quite enjoyed the 61-SFM/R floor-standing speakers. I think it is a great choice for those who are looking for full-range tower speakers. However, as was previously mentioned, many of its best qualities can be had in RBH’s 61-SF/R bookshelf speakers, and if I were planning on using subs, I would just get the bookshelf speaker variant. But for those who do not want to sacrifice floor space or deal with the bass management of subwoofers, the 61-SFM/R is a loudspeaker that deserves to be looked at very closely by speaker shoppers.

The Score Card

The scoring below is based on each piece of equipment doing the duty it is designed for. The numbers are weighed heavily with respect to the individual cost of each unit, thus giving a rating roughly equal to:

Performance × Price Factor/Value = Rating

Audioholics.com note: The ratings indicated below are based on subjective listening and objective testing of the product in question. The rating scale is based on performance/value ratio. If you notice better performing products in future reviews that have lower numbers in certain areas, be aware that the value factor is most likely the culprit. Other Audioholics reviewers may rate products solely based on performance, and each reviewer has his/her own system for ratings.

Audioholics Rating Scale

• — Excellent
• — Very Good
• — Good
• — Fair
• — Poor

Metric	Rating
Build Quality
Appearance
Treble Extension
Treble Smoothness
Midrange Accuracy
Bass Extension
Bass Accuracy
Imaging
Dynamic Range
Fit and Finish
Performance
Value