Raidho Acoustics D5 Loudspeaker




DanSecula.jpgTime marches on and so does the evolution of audio technology. Such is the case with Raidho (pronounced “Ride-O”) Acoustics, the ultra high-end speaker manufacturer from Pandrup, Denmark. The company’s owners are also its chief engineer/co-designer, Michael Borresen, and co-designer/sales manager Lars Kristensen. During the past several years their audio speakers have garnered consistently positive accolades from around the world. My first experience with a Raidho speaker in my home was October 17, 2013. This was the day I took delivery of their tall, elegant c4.1 speakers. At the time it was Raidho’s reference statement. You can read my article regarding my experience with this exceptional transducer here.

The c4.1s came on line in 2012. I was somewhat surprised to learn that the company announced a new and improved reference flagship speaker called the D5 that would be introduced at the May 2014 High End Audio Show in Munich, Germany. In my experience it is rather unusual for a speaker manufacturer to upgrade their reference product in such a short span of time. I began to inquire about the circumstances surrounding the new D5. I was invited to Blink High End, an excellent audio salon in Cambridge, Massachusetts, owned and operated by Tim Lukas. Tim is a very friendly and knowledgeable fellow who carries the complete Raidho Acoustics and new Anzus lines. He told me that I would be able to speak with Lars Kristensen who was giving a presentation on Raidho speakers in March at his salon. I made the drive from New Jersey to Cambridge, MA to attend Lars’s seminar and we had an interesting discussion about the new Raidho D5 launching in May at the world’s largest high-end audio show held in Munich, Germany.


What has changed in the D5s compared to the c4.1s?

I learned that the D5s look identical to my c4.1s with the exception of the driver color. Those in the D5s are black but for the ribbon tweeter, as they are coated with approximately 1.3 carats each of diamond dust bombarded on a ceramic membrane (thus the D for diamond designation and causing it to be ultra stiff) and are not beige-white as they are in the c4.1s. The new black driver color comes from the carbon content that is mixed with the diamond coating. For a more in-depth explanation of Raidho Acoustics’s diamond technology visit:

Both models incorporate the D’Appolito Array technique that uses the execution of sandwiching a tweeter between two midrange drivers so that the tweeter’s output is directed mostly at listeners in the horizontal plane, minimizing reflections with the floor and ceiling. The dimensions and weight of the new D5 loudspeakers are also nearly identical with those of the c4.1s. Each speaker comes with two pairs of 5-way speaker posts that accept spades or banana plugs which is the same as the c4.1 configuration.

The standard finish of both models is a beautiful high-gloss black. The base list price for the c4.1 is $145,000 and the D5 is $220,000. The D5 can also be ordered in a gorgeous custom high-gloss walnut burl for an extra $20,000 bringing the total to a whopping $240,000!

The extreme difference in price is due to several significant upgrades.  During our conversation at Blink High End, Lars informed me that even though their new D5 loudspeaker physically looks almost exactly like the c4.1s, it is a very significant redesign inside. I gleaned the following significant changes from our discussion:

·       New crossover points

·       New Anzus ‘D’ cable and jumpers replace Valhalla Odin cable

·       Finish now offered in high gloss walnut burl for extra $20K

·       Midrange and base ceramic drivers are replaced with diamond coated drivers adding unparalleled stiffness that eliminates inherent driver noise below 20kHz


Room Setup


The new D5s are located almost exactly where the c4.1s were in my 16ft x 25 ft x 12ft living room. They sound best approximately 53 inches from the rear wall to the front baffle and spread 9.5 ft apart between center baffles. As with the c4.1, the D5s sound best in the near field but still do very well in the far field. My listening location is about 9 ft from the horizontal axis between the speaker baffles. The speakers are toed in so that the baffles are aimed to just outside of my shoulders as I sit in the “sweet spot.”  Each speaker is about 3.0 ft from the sidewalls. This configuration yields an incredible soundstage and disappearing act for the speakers. Initially, I had a room node that produced a slight inarticulate sound in the high bass frequency region during the first hundred hours or so of play. This issue has been completely ameliorated by increasing the speaker break-in time and by placing the speakers slightly more out into the room to their present location. Fortunately, these 375 lbs. per side speakers slide quite easily making it a convenient one-man job to move them. Finally, I used my Behold Electronics’s sophisticated room correction software to finely remove the minor frequency high-bass emphasis I mentioned earlier.

How does the new D5 sound?

Michael Borresen’s chief goal was to design a speaker based on how we actually hear sounds and music. Borresen’s way of doing this is to reduce frequencies in the region where we are most sensitive (1-7 kHz) and reduce them in the frequencies where we are less sensitive (above 20 Hz). He found that his specifications may not look perfect on paper but when he voices his speakers, using his method, the sound is exceptional. I emphatically agree.

I began to critically listen to the new, tall, black D5 beauties after giving them at least two hundred fifty hours of break-in as suggested by Raidho Acoustics. This listener feels more break-in time produced better results. In my experience, long hours of musical break-in rewarded me with something that was well worth the wait. With the sound of the c4.1s still rather fresh in my memory, I immediately heard sounds emanating across my room’s landscape, seemingly appearing out of nothing and morphing into the musical event before my eyes and ears. The lifelike harmonics, tone, and naturalness of voices and instruments gave rise to an exceptionally enjoyable listening experience. Inner detail, enormous width, height, depth, and layering are all hallmarks of this remarkable loudspeaker. The ribbon tweeter, also used in the c4.1s, has 50-times less mass than traditional tweeters, which appears to contribute to the apparent horn-like speed and airy lightness of the sound. The liquid, smooth midrange allowed voices to sound just right and holographically levitate throughout the space in front of me. For those of us who like our bass harmonically correct, with realistic grip that plumbs subterranean depths will also love this aspect of these Raidhos. There is an eerie quietness to these speakers as well that manifests itself by apparently removing all of the mechanical driver noise that so often creeps into one’s listening experience. We ususally don’t notice this kind of noise until it is gone. I clearly remember my terrific c4.1s having similar characteristics but certainly not at the level and degree the “new boys on the block” fulfill this audiophile’s critical requirements.

As usual, I was quite skeptical at first about hearing a significant improvement between my c4.1s and the new D5s because I hold the former in such high esteem. It didn’t take long to clearly hear the improvement and become a believer. I listened to familiar test tracks through the D5s and the music flowed with greater dynamics, transient response, grip in the bass and authority when called for. This speaker has the uncanny ability to keep spatial cues in their proper location even when I deviate several feet, left and right, from the “sweet spot.” The last characteristic is the best from any speaker I’ve had in my home. I am an eclectic music listener and was glad to learn that no matter what genre of music I listened to, nothing was ever shortchanged or left me wanting. If you like your music to sound, “You are there” real with performers in your room, then you owe it to yourself to give these elegant towers of sound reproduction an audition.

Needless to say it is critically important that the supporting cast of electronics you have pushing the music through these Raidhos should also sound world class, to your ears, in order to get the most from these loudspeakers. I am very fortunate to have the Behold Reference preamplifier and amplifier along with the most recent edition of the excellent Laufer Teknik Memory Player 64, my primary input source, satisfying my musical eclectic tastes. This combination has served me very well and now services my new Raidho Acoustics D5 loudspeakers.

Over the years I have noticed very ambitious speakers producing the sound of small close-mic’d ensembles quite well but failing badly when trying to produce dense, large orchestrations like those written in Mahler’s Symphony #5. I heard no congealing of layers during large climaxes while listening to this great work through  the Raidho D5 loudspeakers. They seem to be designed for the purpose of providing superior musical accuracy and enjoyment no matter the size and genre of one’s musical tastes. This has been my and others’ experience during extensive listening sessions.

zubin.jpgMany excellent recordings of Gustav Mahler’s expansive Symphony No. 5 exist. One of my favorites that combine superb performance and sound is Zubin Mehta’s 1990 Teldec 2292-46152-2 recording with the New York Philharmonic. For me, Mehta strikes the right balance between tempo, precision, and romanticism. Superlatives go to the first trumpet player, Phillip Smith, and the outstanding brass playing throughout. The wide dynamics of this great recording are flawlessly captured through the speed and delicate accuracy of the Raidhos. Fast-forward through track one to four minutes forty six seconds and listen to the thrusting, arching, and aching sound layers of Mahler’s melodies loudly playing simultaneously. From the sweet, shimmering violins, through the textured woodwinds and horns, down to the subterranean depths of the low tympani and drum attacks, all are heard with their proper place and weight. These intricate lines can be traced through the D5s like no other loudspeaker I have had at my home.

weavers.jpgAnother excellent sample of music that shows off the refinement of the D5’s is the iconic album called, “The Weavers at Carnegie Hall-1963” This is a Classic record CD of an historic May 2-3, 1963 performance of folk music originally recorded on Vangard, VSD 2150 during a two night concert. Classic Records remastered the original recording and released it in 2000 in pristine 24-bit/96kHz version (courtesy Vangard Records, a Welk Music Group Company DAD 1041). The seven performers in the group were: Ernie Krause, Frank Hamilton, Pete Seeger, Erik Darling, Ronnie Gilbert, Lee Hayes, and Fred Hellerman. The stars and planets aligned on those two evenings to produce an historic recorded live performance of The Weavers hitting on all cylinders as they sang and played their brand of folk music in one of the best sounding music halls in the world. The ambience in the hall can be clearly heard as the audience showed their loving approval by clapping and often singing along with The Weavers as they performed shoulder to shoulder across the front of the stage.  My Raidhos picked up every nuance of sound in the hall on this exemplary recording to an extent I have not heard anywhere before.

Every track is a gem. One of my favorites is track thirteen: “Goodnight Irene.” This rendition has several members in the ensemble taking turns with the melody while the others lend their support. The quality sound of the great hall and the nearly perfect original CD recording remastering is certainly one of the best examples of performance and technology blending into a synergistic aural masterpiece. The D5s capture the recording so well that it becomes a fully immersive experience for the listener.

A few of my audiophile friends familiar with my past setups recently stopped by for some pizza and to weigh in on my new addition. Each was quite effusive with their very positive comments, such as: “Gorgeous for the eyes and ears,” “startling,” “it puts me in the moment,” and “I’ve heard something new contained on my favorite track.” Two had issues with the size and cost of the speakers as it related to their home’s space and finances.  It is always helpful to get honest feedback from those whose opinions you greatly respect and it is especially gratifying when the opinions are so positive.

A Personal Shout Out

My good friend Clement Perry (CP), has built and refined his substantial Sunny Majestic horn loudspeakers/Behold Electronics/Memory Player-based rig over the years to a level that truly deserves the highest accolades for the current state of the art in high-end sound. Many visitors attest to the performance his system offers with each visit. CP has given me much valuable guidance over the years regarding building of my own system. In fact – with the exception of his superb Sunny Majestic horn loudspeakers – he and I share much of the same electronics and tweaks (I also thank CP for bringing these tweaks to my attention). I’m just one of many audiophiles he has generously helped along the way. With the addition of these new beautiful Raidho D5 loudspeakers in my living room, the quality of sound, in my opinion, is now in the same zip code as my dear friend CP… and that’s saying a lot!

In The End

There are only a handful of truly world-class loudspeakers that perform at the highest level with the commensurate, necessary supporting equipment. All of us know that at this profound level it comes down to one’s personal taste when choosing a speaker for the best reproduction of sound. After listening to many of the most well known brands of reference loudspeakers today, the new Raidho Acoustics D5 loudspeaker must be considered in the conversation for being one the best speakers in the world.

Unfortunately few music lovers will be able to afford the price of admission to get into this rarefied audio club. Cutting edge technology doesn’t come cheaply. However, those fortunate enough will not be disappointed and will undoubtedly be thrilled with the special sound their purchase will provide.  As a lover of great musical art and sound you owe it to yourself to seek out these extraordinary marvels to hear what the current state of the art in high-end loudspeakers has achieved.

I could cite many more high quality recorded performances as those I mentioned earlier that are often included in reviews like this that highlight a specific aspect of a speaker’s sound. I’d rather get to the point, by simply saying, that listening to fine music through these technological works of art, no matter one’s taste, I suspect these speakers will set a new benchmark for providing outstanding musical enjoyment as they have for me. I give the Raidho Acoustics D5 loudspeakers my highest recommendation. 




Technical Specifications

Type: Three-way, five driver dynamic floor standing loudspeaker

Finish: Piano Black/Walnut Burl

Enclosure: Vented design, port in front panel

Drive Units: One sealed-ribbon tweeter, two 3.94-inch diamond midrange drivers,

Four 6.3-inch diamond bass drivers

Size: 9.84 inches x 26.4 inches x 79.1 inches

Weight: 364 lbs.

Freq. Response: 25Hz-50kHz

Impedance: >5.8 ohm

Crossover: 150Hz and 3 kHz second order

Minimum Amplification: >50W

Price: $220,000/$240,000 in walnut burl finish

Denmark (Pandrup)

Raidho Acoustics

CO/Dantax Radio A/S

Bransagervej 15

9490 Pandrup, Denmark


Web site:


Dan Secula’s Associated Equipment 

Loudspeaker: Raidho Acoustics D5 Cables: Klee Grand Illusion Loudspeaker Cable, Klee TruBalance, Klee Digital Waveguide Power Equipment: Anzus D Mainz 8 Power Distributor, Anzus D Power cable, IPC Sound Power AC Conditioner, Bybee Wire Power Conditioner Amplification: Behold 768 preamplifier with Room Correction, Behold BPA768 Reference Amplifier Digital Sources: Laufer Teknik Memory Player 64, Tascam DV-RA1000HD, Tascam CD-RW402, Oppo 105 DVD Player, Behold CD Transport, Sony DTC-2000ES DAT Analog SourcesRevox B77 Reel-to-Reel Tape Recorder, Tandberg 3001A FM Tuner Accessories: bsg technologies QOL Signal Completion Stage, IPC Acoustic Equalizer: (4), IPC Acoustic Energizer: (5), Stein Music Harmonizer: (6), Stein Speaker Match, Argent Room Lenses, High End Novem PMR Premium Mk. II, WA Quantum Chips, Audio Magic Speaker Clarifier, Bybee Golden Goddess Speaker Bullets (latest version), LessLoss Blackbody: 3




Be the first to comment on: Raidho Acoustics D5 Loudspeaker

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

DR Acoustics (79)Dynamique Audio (61)Essenceright (64)

Stereo Times Masthead

Clement Perry

Dave Thomas

Senior Editors
Frank Alles, Mike Girardi, Key Kim, Russell Lichter, Terry London, Moreno Mitchell, Paul Szabady, Bill Wells, Mike Wright, Stephen Yan, and Rob Dockery

Current Contributors
David Abramson, Tim Barrall, Dave Allison, Ron Cook, Lewis Dardick, Dan Secula, Don Shaulis, Greg Simmons, Eric Teh, Greg Voth, Richard Willie, Ed Van Winkle, and Rob Dockery

Music Reviewers:
Carlos Sanchez, John Jonczyk, John Sprung and Russell Lichter

Site Management  Clement Perry

Ad Designer: Martin Perry