In 1959 the BBC developed a two-way studio monitor, the LS5/1. After testing a 305mm bass cone made with new thermoplastics, they developed the LS5/5 and LS5/6 monitors, in a very compact design that proved very useful, and the start of many new BBC monitors. They licenced the designs to British manufacturers, explaining the research and materials technology. As a result, companies like Harbeth, Spendor, Rogers Audio, Chartwell, Goodmans and Stirling Broadcast flourished.

Harbeth

Harbeth was founded in 1977 by Dudley Harwood, the senior engineer at the BBC's Research Department. The name Harbeth is an amalgam of HARwood and elizaBETH, his wife. It was Harwood's discovery and patenting of the application of polypropylene plastic that paved the way for him to retire from the BBC and to found Harbeth the speaker company.

The original Harbeth HL Monitor (known as the Mk1) was the world's first loudspeaker to use the brand new polypropylene cone. Other contemporary monitors used Bextrene as the bass/mid cone material, which required manually applying doping to the cones. Harwood's polypropylene did not require this doping process as it was inherently better damped, so it was lighter, louder, cheaper and more repeatable to manufacture.

You can read the full story at the Harbeth website.

Alan Shaw is the current owner and designer at Harbeth since around 1986. The factory is located in Lindfield, in West Sussex (south of London), England where everything is designed and manufactured. 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, every speaker is again tested before shipment, to ensure that it leaves the factory in perfect condition and to the designer’s specification. They are shipped as pairs of speakers, with a left and right speaker.

Harbeth HL-Compact 7ES-3

The subject of this review is the Harbeth HL-Compact 7ES-3. It is available in any of 5 wood finishes, Eucalyptus, Cherry, Maple, Rosewood and Tiger Ebony. My sample pair were finished in Eucalyptus ($4,990 RRP) and look bright and modern, with the ability to blend with most décor. The retail price in Australia ranges from $4,790 to $5,490 depending on the selected veneer. The Compact 7ES-3 are the second speaker in the Harbeth line-up and the range tops out with the Harbeth Monitor 40.2 for $22,190 (RRP).

I borrowed a good set of speaker stands that the Australian Harbeth distributor, Audio Magic, also imports, from the HiFi Racks Ltd brand ($590 RRP). They are handmade in the UK with solid hardwood construction. These stands are strong and rigid, perfect for supporting the loudspeaker without any movement and providing ideal decoupling from the floor. They came with metal spikes for carpet or hard surfaces.

The Compact 7ES-3 speakers are a medium size speaker, measuring 520mm tall x 272mm wide and 305mm deep. With them sitting on the stands, the tweeter is 1000mm from the floor. They are a two-way ported design, using the Harbeth RADIAL™ drive.

Harbeth say:

You can think of Harbeth RADIAL™ technology as a reinforced plastic which solves numerous engineering challenges.  Unless cones behave in a pistonic way across the entire audio range, as RADIAL™ ones do, it’s impossible to achieve a really natural sound.

Evidently the non-disclosed material is extremely stiff and rigid, with Harbeth pointing out that the cone can withstand the weight of a hefty 4.9kg steel billet placed on top of it, in contrast to many cones that are pretty feeble. The mid/bass is a 200mm RADIAL2 driver with a complementary 25mm Ferro-cooled dome tweeter. The quoted frequency response is 45Hz – 20kHz within 3dB.

Construction

In their construction, Harbeth uses ‘thin-wall’ cabinet technology. This concept was thoroughly researched by Harbeth's founder Dudley Harwood at the BBC and the company has stuck with it over the years. It is a contributing factor in the Harbeth “house” sound.

Harbeth state:

The cabinets are crafted from thin (typically 12mm) panels which, by virtue of their profile, lend themselves to being internally acoustically damped in a way that is impossible with conventional 'thick wall' panels such as 18mm (3/4 inch) chipboard or MDF. We work harmoniously with the knowledge that the human ear is intolerant of buried resonance in the middle frequencies to steer panel resonances out of the critical band and into the region of inaudibility.

You can see by the photos, there are screws holding both the front and rear panels together to the frame. Despite the visible screws, the speakers appear to be manufactured to a high standard with a perfect veneer finish. The front grill is removable, with some care, but the speaker has been engineered to be used with the grill in place. The binding posts are situated at the rear of the speaker and are gold plated brass, suitable for spades, bare wire or banana plugs.

Setup

I used the Compact 7ES-3 speakers with a variety of amplifiers, including a small and colourful Dared 25W tube amp, through to the powerful NAD M22 250W class D (review coming). They appear to be quite easy to drive and there is no real need to have a very powerful amplifier to drive the Harbeth’s to beyond ‘realistic’ levels. As per the detailed instruction manual, they are best placed away from wall boundaries, a minimum of 0.75m. This avoids ‘acoustically coupling’ a speaker to the surface (wall, floor, ceiling or corner.) Placing bookshelves or furnishings behind or beside a speaker can greatly improve the low frequency response. I tried the speakers both in a very large room with them 1.5 - 2m away from the walls, as well as in smaller room with nearfield listening. In both cases the tonal balance was very similar, so with a little care, it would be safe to assume that they are quite room friendly and that most users will not have problems finding a suitable position for enjoyable listening. It is also recommend that you provide some angle or toe-in from the speaker face to the listener, with between 0 and 10 degrees suggested.

Although Harbeth suggest a few hours or less to 'burn-in' the speakers, I found that it took a couple of days before they became tonally stable and the initial lump in the mid bass to smooth out. This is entirely normal as far as I’m concerned and it is not a reflection on the manufacturer or the product. Everything takes some playing time to season the many internal components that make up a complex product.

Once I was satisfied that everything was sounding at its best, I put on some familiar music and started to give them a serious listen. I found that the Harbeth’s sounded very well matched to the Dared Saturn Signature 25W valve integrated amplifier (review coming), so much of my listening impressions are with that amplifier. I used the amps 8ohm speaker outputs they sounded best this way, along with trying a couple of brands of good quality speaker cables including the excellent Tellurium Q Ultra Black. Cables certainly do make a difference with these loudspeakers.

Listening

My first impressions were that the speakers exhibited a great deal of detail and complexity. They are very revealing of musical nuances and harmonics, particularly in the midrange and treble regions. This initial impression remained throughout the review period. Well recorded natural instruments and voices were portrayed really cleanly and were relayed with a lifelike realism. The treble was very smooth, highly detailed, reasonably extended and was never harsh, taxing or overbearing. I would go so far as to say that it made music sound sweet and pleasant. It was very well integrated with the midrange, with no apparent gaps, so the crossover design was spot on. Listening to wooden instruments, like strings, piano and acoustic guitar, or female voices were very pleasing and had a wonderfully lush euphoric sound.

The lower midrange to bass was also smooth but with less power, depth and extension than I am used to. It rolls off smoothly and what is available, is fine so long as you don’t overly tax them. I would have preferred a little more, particularly as I listen to wide variety of music genres, but this loudspeaker has not been designed with that in mind. In my research I found 2 interesting suggestions that Harbeth publish in their FAQ:

There is no such thing as a 'perfect speaker' - it all depends what you want the speaker to do for you. Do you want it to spice-up the recording? To give you the immediacy of a front row seat? To project high frequencies with a glass-like cutting edge? A thumping bass end? In that case, I regret to say there is nothing in the Harbeth line-up that will really suit your taste.

And also:

Play at a reasonable level: Harbeth speakers are deliberately designed to sound just like real life when played at a normal, reasonable level. They do not need to be driven hard and unlike many other speakers that do not need to be pushed to 'come alive'.

So headbangers with a penchant for annoying the neighbours need not apply. That is not what these speakers are about. Classical music, folk, ambient, chamber, jazz, instrumental, voices, etc. really do work well. AC/DC does not. I’m pleased that Harbeth have the good sense to say that up front, not everyone is that honest.

It was with simple recordings, particularly tracks without a lot of deep bass energy that they sounded at their best, and with the most accuracy. Over a couple of weeks I tried a number of well recorded musical genres that included a good mix of symphonic and chamber, jazz, vocals and small group indie in the mix.

David Elias “Vision of Her” is a simple track that features an upright bass and two acoustic guitars. It exhibits a lovely tonal quality of the guitars, the plucking/strumming pattern is superb and the vocal is very complimentary. Through the Compact 7ES-3 the track is reproduced in a very musical way, with a touch of added warmth. Very inviting. Next was Norwegian 2L label’s recording of “Violin Concerto No. 4 in D major, K218- Allegro” with Marianne Thorsen. The horsehair bow drawn across the violin strings sounds alive, invigorating, with fine detail and delivered in a manner that is not tiring and never grating, neither is it harmonically bare or boring.

Pilgrimage “Campus Stella/Field of Stars” from the “9 Songs of Ecstasy” album combines a modern bass line and percussion along with an ethereal vocal. The track has considerable bass content and this is nicely conveyed, with a reasonable amount of bass weight that works well with the rest of the track, setting a nice tempo and drive. The vocal is the beautiful voice of Catherine Bott, a London based soprano. It is a stylistic approach to a medieval sound and it sounds very evocative through the Harbeth’s.

I’m a big fan of Bon Iver. One of my Canadian friends always corrects me with the proper pronunciation of his name, but in any case we agree that he is very talented. Listening to “Skinny Love” from the “For Emma, Forever Ago” album, was very enjoyable with lots of detail, colour and naturalness. The Harbeth’s were very comfortable playing this track. But a different track, “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 were heard slightly diffused. You can hear the cabinet resonate at times with the deeper overdubbed voice and guitar notes.

I carefully placed a large 2Kg weight on top of each speaker and replayed the same track again. Sure enough, much of the resonance in the bass was diminished. I don’t suggest that they are used that way, but it was an experiment to prove that a “thin-wall” speaker cabinet can be a double edged sword.

I believe that much of the midrange detail, colour and lushness is the result of this design. So long as it is played at reasonable volume levels and without too much deep bass content all is well. If you push the speaker into high volume settings and with lots of bass energy, the cabinet will vibrate sympathetically and produce audible resonances that some may not appreciate. It wouldn’t be accurate. So my earlier advice as to the type of music that you play is relevant. The fact that Harbeth is so well regarded by so many, is testament to the principles researched by the BBC so many years ago working, to add enjoyment to many happy listeners.

Comparisons

I was fortunate enough to have the Rogers LS5/9 65th Anniversary Edition loudspeakers here in the office for audition and comparison. They are very similar in having a long and rich BBC monitor heritage and being of similar size and driver specification. The Rogers are in fact 25-40mm overall smaller in size, but they are around 5Kg heavier in weight. Giving the cabinet sides a tap with your knuckles revealed quite a different resonance, with far more of a solid thunk to the Rogers. Swapping out the Harbeth and Rogers in quick succession in the same system and sitting on the same speaker stands was really interesting.    

Matt Corby “Made of Stone” has a solo piano opening that sounds superb, very clean with large amounts of reverb and decay. During the second chorus crescendo at 2:40 particularly, when the bass and drums get loud, the added bass confuses the whole sound of the Harbeth C7ES-3 with the rest of the content buried and blurred due to the cabinet resonance. By comparison the Rogers LS5/9 didn’t have the gorgeous smooth top end treble of the Harbeth’s, but sounded better in the bass area, with more clean effortless bass notes that gave it a better musical foundation in the loud passages.  It was a similar story playing Dead Can Dance “Song of the Nile”. The drums and male voices were produced cleaner and more solidly through the Rogers, but the Harbeth was better in the top end with just a little more ‘polish’. Both have a lovely, colourful and musical midrange, and with very good imaging. It all depends on your musical taste and preference for the top or bottom ends of the spectrum.   

I also used both brands listening to speech, a sound book with male voices, as well as for general TV listening. It is no surprise that they both sound superb in this role. With the speech-based origins in broadcasting, these speakers reproduce speech naturally and convincingly. It was a pleasure to listen for hours at a time, without fatigue and with great articulation and coherence.

Conclusion

It is important to realise any and all strengths or weaknesses in any product that you are considering for purchase. Knowing how you intend to use a product and your particular preferred genres of music, influences the style of speaker that you should own. The Harbeth Compact 7ES-3 is not a large heavy speaker, so don’t expect strong thumping bass from it, as it’s just not built that way or with that in mind.

I can confirm that the sound qualities and recommendations described by Harbeth are real and factual which is something that I find refreshing.  They are fully capable of producing convincing and emotive music, with clarity and great beauty. I can now understand why many owners love their Harbeth’s and won’t buy anything else.

I believe that they represent reasonably good value for money. And do consider the cost of a good set of speaker stands into the equation, as stands are critical to getting a good synergy working. Thankfully they work very well with any clean sounding amplifier of modest output that doesn’t have to cost the earth. Using a good valve amp is simply icing on top.  

When you think about it, Harbeth have a wonderful heritage that is traceable back to the late 1940’s when the BBC started a program to raise the standard of loudspeakers for everyone. They should be applauded for their efforts, as they also should for the unique products they produce that are themselves musical instruments.

Harbeth is distributed in Australia by Audio Magic.

Pros

Highly detailed, emotive sound. Easy to drive and to listen to. Sweet treble

Cons

Won’t suit some musical tastes. Slightly bass shy, Lively cabinet

Specifications

• Transducer system: 2-way vented: 200mm Harbeth RADIAL2™ bass/mid; 25mm Ferro-cooled dome tweeter with HexGrille
• Freq. response: 45Hz-20kHz +/-3dB Free space, grille on, smooth off-axis response      
• Impedance: 6 ohms
• Sensitivity: 86dB/1W/1m
• Amplifier suggestion: Works with a wide range of amplifiers, ideally from 25W/channel
• Power handling: 150W programme
• Connector: Two 4mm gold-plated binding posts for wires or plugs
• Dimensions: (hxwxd) 520 x 272 x 305mm (+12mm for grille and binding posts)
• Finish:  Cherry, eucalyptus, rosewood, maple, tiger ebony
• Space needs: Overall response optimised for use away from walls
• Stands to bring ears level with tweeters: typically 15 - 21 inches. (Tweeter: 440mm up from cabinet base)
• Weight: 13.2kg each, without packing