With the success of the previous series, why did Harbeth need to change it?   

As you know, we have been running the Standard series alongside the Anniversary series on our production line for a few years. You would be surprised at how few components are common to these two series. The cabinets are different (veneer choices and cut-out for the terminals), all the capacitors are of a different style, shape and size on the crossover boards and there is an adaptor board in the Anniversary speaker to convert the connection of the WBT terminals into a long-term ‘Harbeth standard’ for internal wiring. 

Taken together, this has expanded the number of unique products that we offer to over forty-five, and that has proved to be a complex logistical matter for a small company. So the core rationale behind the planned phase-out of the Anniversary series has been ‘simplification and standardisation’ – the new XD series has reduced forty-five product lines into sixteen, with efficiency gains throughout production. 

How did you first approach the challenge of improving the new XD series? 

Interesting question. My first desire was to eliminate all the cosmetic features of the Anniversary series as that moment of celebration has now passed. That means, any elements which added complexity (such as the WBT connectors), even though they looked impressive, had to be removed. Of course, the customers had become accustomed to the Anniversary sonic performance and we had to at least match that in the XD series, but in a simplified package. The art was to know what features added complexity without justified sonic advantage and remove only those. 

 What are the main innovations that have made the difference to the sound of the new XD series? 

My test and measurement facilities give me a sonic ‘microscope’ into the performance of the speaker. Over the years I have invested in a more and more powerful analytical ‘microscope’, and small deviations from perfection that I could not observe years ago are now very obvious. So I have flattened-out small ‘lumps and bumps’ in the frequency response by using custom made resistors, coils and capacitors. So the overall sound is better integrated bass/mid/top. 

In particular, which speaker are you most proud of in the new range? 

I’ve always had a particular fondness for the Compact 7. I like the form factor. When I heard the Compact 7ES-3 I could hardly believe that it was the product of my own creation! Of course, the completely redesigned P3ESR-XD is also very special. 

If you had to summarise the effect of all these changes? 

I have, coincidentally, been reading over the last year about Japanese management practice, and in particular the influence of Honda in LEAN manufacturing philosophy. It seems that business efficiency is really the secret of great success, and the XD series is not just another Harbeth family, but the encapsulation of a shift in Harbeth’s approach to production.