Harbeth Super HL5plus Loudspeakers Review

The current line-up features just five models for the domestic market, and four that are specifically aimed at the pro-audio market.

Audio Magic, the Australian distributors for Harbeth asked us to take a look at Harbeth Super HL5plus, the second most expensive model in the current line-up. It retails in Australia from $6,890 for the Cherry wood finish, or for $7,090 in Eucalyptus (as reviewed) through to $7,290 for Tiger Ebony or Rosewood finishes. Harbeth finish their speakers with real wood veneer with a thin coat of cellulose lacquer to protect it. Audio Magic also mentioned that in spite of the falling Australian dollar, they are holding their prices. This is a win for the consumer, as you’ll get a better deal locally than purchasing them in the US or the UK. 

The Harbeth factory is located in West Sussex (south of London), England, where everything is designed and manufactured. One could successfully argue that the Super HL5plus is part of a design tradition that can be traced back to the BBC-inspired research that was partly responsible for what can be called the classic British loudspeaker.

The Harbeth HL loudspeaker was originally launched in 1977 and since then has had many updates. In 2000 it was updated to the Super HL5 with the addition of a super tweeter, and then in 2014 to the Super HL5plus. It is the ninth generation in this line of Dudley Harwood's original BBC monitor. Over that period of time most manufactures would be at least tempted to follow the fad that exists within audio circles, that is to significantly change the styling, the design, in fact everything in an effort to capitalise on the fervour of a new model release. But Harbeth have managed to keep the basic design the same make only changes that result in sonic improvements.

The Super HL5plus is a 3-way vented speaker that features a 200mm Harbeth RADIAL2™ bass/mid driver made in-house, a 25mm Ferro-cooled dome tweeter, and a 20mm dome super tweeter that have been manufactured by SEAS in Norway to Harbeth's exacting specifications.  RADIAL stands for ‘Research and Development Into Advanced Loudspeakers’. The Radial 2 iteration uses an updated polymer blend for the cone material and a change to the driver surround. The 8” Radial driver handles bass (the -3dB point is 40Hz), midrange and lower-treble frequencies, crossing over to the tweeter at 3.3kHz, which in turn augments to the super tweeter at 12kHz. The all-important crossover has been given a redesign to complement the updated driver configuration.  

The cabinet is made to the typical BBC British monitor design methodology of using very thin (8mm and 12 mm) timber walls with tuned or controlled resonance. I was not about to open up the review pair of speakers, but I have seen photos of the interior of the loudspeaker. I can report that there is no structural reinforcing or brace plates anywhere to be found inside.  Rather, the interior is lined with dense acoustic foam and has a thick and heavy tar like sheet on the back panel directly behind the drivers to absorb rear firing energy from exciting the rear wall. The interior is otherwise empty except for a 100mm thick acoustic foam block that is snuggly placed inside the enclosure. There is no damping on the front baffle, but there is a plastic bass reflex port that is positioned underneath and to the right of the bass driver.

The front is covered by a removable black grill cloth that is held tightly in place by a well formed metal frame. Removing the grill there are a number of chemically coated black screws that attach the front panel to the cabinet, while the rear panel uses brass screws to hold it in place. It’s hard to not notice the simplicity of the build and visible use of timber screws, but that is exactly how Harbeth believes loudspeakers should be manufactured. It may look a little DIY to the casual observer, but upon closer examination it is obvious that a great deal of care and attention has been paid to the fit and finish. It has been put together with a lot of consideration and attention to detail, even the cabinet screws have been carefully torqued. They have making them for 38 years now, so they know exactly what they are doing.

Quality control is paramount at Harbeth, as every individual drive unit is measured and pair-matched before assembly. Each crossover board is carefully checked and tested using computer-controlled equipment. At the end of assembly, each unit is tested before shipment, ensuring the finished product leaves the factory according to the designer’s specification. They are shipped as pairs of speakers, with a left and a right speaker. A small L or R is printed on the end of the serial numbers to indicate the correct orientation. The small Harbeth logo on the front grill sits to the inside of each of the boxes when you have them correctly oriented.

At the back there are two sets of speaker binding posts, unlabelled but identified by the red or black stripes on the brass thumb screws.

Stands

The Super HL5plus is more substantial in size than a typical bookshelf sized loudspeaker, being a stand-mount design with the traditional 'two cubic feet' of volume proportions found in many BBC monitors. They stand 64cm tall and 32cm wide and are made to be situated with the tweeters at ear level. This necessitates the use of speaker stands which Harbeth do not offer.

Thankfully Audio Magic was able to supply a set of HiFi Racks Limited stands that are purpose built for the Super HL5plus dimensions. They are finished in “solid oak satin black” finish and really look lovely. They are extremely strong and stable stands, made of solid hardwood timber and weighing 10kg each. At $1,190 RRP for the pair they’re not exactly cheap, again affected by the recent weakening of the dollar. With the supplied carpet spikes in place, the super tweeter is at the height of my ears when I’m in my listening seat.

Setup

Before critical listening, I found that at about the 150 hour mark that they started to really smoothen out, and noticed that they played louder at a given volume than before. I typically use the “Tellurium Q System Enhancement” CD, playing it continuously to achieve adequate run-in time.

The speaker connections have a metal bridging strip installed that connects the high and low elements of the crossover. This allows you to connect a single set of speaker cables to your amplifier. By removing this metal strip, you can bi-wire the speakers with two pairs of cables, or even ‘bi-amp’ however Harbeth does not recommend this. I used Synergistic Research Atmosphere UEF Level 4 speaker cables (review coming) bi-wired for this review. These were connected primarily to the NAD Masters M12/M22 power and pre amplifier combination for the burn-in and initial testing period, playing back digital files and CD’s from an AVM CS2.2 and the AVM SD3.2 (review coming).

Listening Impressions

The very first impression that I had of the Super HL5plus was very positive. Without the benefit of many days of seasoning or finding the optimum position within the listening room, it was obvious that they are a loudspeaker with a wide array of capabilities. They fill a room with a large soundstage, and a full lush warm sound that had some typical BBC monitor mid bass bloom. But as I gave them some time to bed in and then experimented with positioning, their true capabilities were shown and it was well worth the effort. They certainly smoothed out and became almost totally neutral. I have to admit that I wasn’t expecting them to neutralise to the extent that they did and to sound so darn good. They played very well in my small listening room, but also sounded even better in a large open space.

They have an innate ability to draw you in to the sound and to be immersed in the experience. For instance, playing “Miss Bea” by the McCoy Tyner Quartet was eye opening in the way that all the instruments played so cleanly in their own space within the soundstage. Apparent was the pure and liquid midrange that allowed me to relish the tonality of each of them, especially the tenor saxophone of Joe Henderson. His playing imparted a sense of freedom and calming carefreeness that I really enjoyed. They are able to deliver a reasonable sense of touch, depending on the amplifier powering them. The speed and timing is very good at all frequencies except for the bass, were it is just a touch slower than the higher registers are. This wasn’t always noticed and I don’t consider this to be a flaw, it is simply a characteristic of the sound that is presented.

Johnny Frigo playing jazz guitar at a frantic pace on “Stompin' At The Savoy”, with the two guitars of Bucky and John Pizzarelli has little bass content but has plenty of mids and highs. The pace and timing of the three guitars is spot on, as each is easy to pick out and follow. The success of the track depends on the precise timing of each of the players and it absolutely succeeds on that count.

Playing more contemporary music that has a solid bass line that drives the tune, “Broken Skin” by Nitin Sawhney highlights a slight lack of uniformity. It is the first track off the album with the same name and has been very well recorded, with deep strong and extended bass lines. The Super HL5plus has no problem playing the bass cleanly with good, but certainly not ultimate bass extension; after all it only uses a single 200mm (or 8”) driver. The bass lines and kick drum seem just a tad slow as if it takes a moment or so for the deeper bass to fully extend and flesh out.

As mentioned earlier, this is certainly dependent upon the power amplifier that you use. With the Elektra Reference HD which (250W/channel class A/B) the pace seemed a touch slower and more ponderous than with the NAD M12. The NAD offers similar output power, but like most switching amplifiers seems to have a little extra delivery speed in the sub 100hz area. Both are excellent amplifiers but they enjoy differing characteristics. That realisation highlights another attribute of the Harbeths; neutrality and faithfulness to the auxiliary equipment.

The quality and attributes of the source, cabling and amplification will play an important role in the overall enjoyment of the Harbeth Super HL5plus as they are particularly true to them. I wouldn’t say that they’re fussy but if you do take the time to mix and match your components to your version of sonic nirvana, then you will surely benefit from your choices.

I also tried a pair of Triode TRV-M88SE mono block power amps (review coming). These are a modern Japanese made amplifier that utilises a pair of KT88 vacuum tubes running in class AB and rated at 50W/channel. I’ve heard people say that Harbeths usually work very well with tube amps and I’m happy to report that it’s true. The Triodes amplifiers were certainly the best pairing partners that I heard in my system. Wow, there was breathtaking transparency, even more detail and realism and a naturalness that made me just want to keep playing more and more of my favourite music. It was just so involving musically. The combination is special, the synergy outstanding. 

I left my system playing while I briefly left to go and help out a neighbour. When I returned “Tides” by Nitin Sawhney happened to be playing, reasonably softly and as I walked into my home I was immediately drawn into the music and the accuracy of the piano and the fine detail and phrasing of the cymbal work. It was beautiful and engaging, relaxed and yet dynamic, full of natural harmonics and colourful tones. It sounded right and I didn’t wish for anything more.

The Harbeth User Guild discusses the need for about 45W into 8 ohm per channel as a good starting point for domestic use and that 100W will provide “a reserve of power for the louder music passages if used with care.” I was satisfied with the 50W into 8 ohm per channel that the Triode amps delivered; they had the current delivery capability to usefully control the speaker. It could easily play at “natural and safe listening levels” that the user guild speaks of, but on very dynamic or music with lots of bass energy, they started to compress the peaks and wouldn’t go overly loud without sounding distorted. More power will always allow greater headroom and the ability to play louder averages and peaks.

The Super HL5plus can certainly take the increased power and convert it into greater sound energy, but they feel more comfortable playing at recommended “natural” listening levels. Daft Punk “Lose Yourself to Dance” has a heavy bass line and rhythmic kick drum with lots of bass energy in it. They will certainly play this popular dance track with gusto and force, but the really outstanding quality is not so much how well it handles the bass or how loud they will go, but how well the midrange and top end integrates allowing focus on the brilliant rhythm guitar, Pharrell Williams voice and the wonderful timing of all the parts that combine to make it so enjoyable.

There is no doubt that the Harbeths have very good resolving ability, so virtually everything it plays has a clarity and precision to it. I lined up the Abegg Trio playing Haydns “Moderato Assai” has cleanliness and a purity that is just so easy to listen to. Every note played from the horns sounding just as it should be, with the notes leaving the instrument and filling the playing room with natural reverb as they perfectly intermingle with the violins and other instruments. The soundstage is beyond reproach with great front to back distinction and a huge but natural spread that extended right across the listening room. 

Super HL5plus vs HL Compact 7ES-3

I can clearly remember the last pair of Harbeths that I reviewed, the HL Compact 7ES-3. This model also uses the RADIAL2 200mm bass driver, but are in a smaller sized enclosure. I commented extensively on the construction of the cabinet and described the thin wall philosophy and how it affected the overall sound quality. I wasn’t fully convinced that the lack of strength and mass in the cabinet allowed a full range of musical genres to be played in an uncoloured manner and that some box colorations are audible. However in the Super HL5plus the box colorations are virtually absent, even though the same construction is used, along with the same bass driver. What has changed is the increase in box dimensions and the resulting increase of internal volume. Perhaps it’s the additional volume, perhaps it’s the way that the interior is damped, I’m really not certain. But what I am certain of is that it sounds much more refined and cleaner, whilst essentially still having the same character. The result is that a wider range of musical genres can be played with complete confidence. Even music with heavy bass content and rhythmic drive sounds awesome, albeit without the highest range of available output levels available.

In that last review I listened to Bon Iver’s “Lump Sum” and I wrote that:

“Lump Sum” has more musical energy content in a region that the Harbeth’s are less comfortable with. The strumming of the guitar’s lower registers are heard slightly diffused. You can hear the cabinet resonate at times with the deeper overdubbed voice and guitar notes.

So I took the opportunity to listen to the same track with the Super HL5plus as it is a repeatable test. Sure enough, the larger Harbeths sailed through the track without any untoward cabinet resonances. The deeper notes are replayed cleanly without the cabinet induced overhang of the HL Compact 7ES-3. Again, I can’t explain how it achieved it, but it really made me enjoy the larger speaker much more. Not only are the deeper notes cleaner but they are also extending lower and with more push or energy than the Compact 7’s. The sub 200hz region is much more linear and smoother and that really adds class and polish to what is an already accomplished speaker.

Conclusion

It is easy to understand why the Super HL5plus has consistently been Harbeths best-selling line for some 38 years now. Whatever musical genre is played, the Harbeths will faithfully communicate the essence of what is being played along with all the detail, harmonics, timbre, tonality, nuances, dynamics and richness of the original recording. It is a faithful and honest loudspeaker that gets out of the way of the music and delivers music in a truthful manner, never edgy but always smooth, warm and complementary. They have the ability to accurately relay the characteristics of the axillary equipment, so some care should be taken to get the absolute best of them.

I love the manner in which they fill the room with a huge soundstage and allow one to become engrossed and enthralled in the performance. This speaker allows music to come alive and to disappear in the room, being left with the performance. The balance that they exhibit with well recorded acoustic music is absolutely stunning. They reveal so much detail, with so much clarity and purity, that you are sure to discover new things in your musical collection.

As a value equation, it is easy to subjectively hear the $2,000 odd difference between these and the smaller model on sound quality alone. When you consider that the next model up in the Harbeth product range is the 40.2 and is priced at over $21,000, the Super HL5plus start to look like a bit of a bargain. I’m sure that you will be hard pressed to find another loudspeaker, from any international brand name, to do all the things that the Harbeths do for the asking price. They certainly have a charm and magic about them that is intoxicating. I really enjoyed listening to them and heartily recommend to anyone looking at purchasing a loudspeaker under $10,000 to give the Harbeths a serious listen. You too may just fall in love with them.

Pro’s

• Musicalness, Tonality, Natural and engrossing sound quality, better sound and value than the HL Compact 7ES-3

Con’s

• Old school DIY look, slightly slow bass

Harbeth is distributed in Australia by Audio Magic.

Specifications

• Transducer system: 3-way vented: 200mm Harbeth RADIAL2™ bass/mid; 25mm Ferro-cooled done tweeter, 20mm dome SuperTweeter
• Freq. response: 40Hz-20kHz +/-3dB free-space, grille on, smooth off-axis response
• Impedance: 6 ohms.
• Sensitivity: 86dB/1W/1m
• Amp. suggestion: Works with a wide range of amplifiers, ideally from 25W/channel.
• Power handling: 150W programme
• Connector: Four 4mm gold-plated binding posts for wires or plugs (biwireable)
• Dimensions (hxwxd): 635 x 322 x 300mm (+12mm for grille and binding posts)
• Finish: Cherry, tiger ebony, eucalyptus, rosewood.
• Space needs: Overall response optimised for use away from walls.
• Stands: To bring ears level with tweeters: typically 16-20 inches. (Tweeter: 475mm up from cabinet base)
• Weight: 15.8kg each, unpacked