This site has something for you if you are either making a violin or you want to improve a low cost violin or viola.

By tuning the top & back plates you can get a good instrument that responds well to the bow and that can sound like a £1500 instrument.

 This site available in all the major world languages here at Google translation in French, Spanish, German or Greek  ....

So, what is this site for?

This site is for people who are making a violin or viola, and those who want to modify a low-cost and poor-sounding instrument to dramatically improve its tone and playability.

I’m not trying to sell you anything here. Really. I believe strongly in the ‘Wiki’ idea: I feel a need to communicate what I know, so that’s what I want to do for other amateurs. What I ask in return is to hear your story, so please comment in my blog, or better mail me back to let me know what you’ve learned in fiddle making!

Tap Tones for the front and back of violins.

The front and back of a violin when on their own are called ‘plates’. Adjust the tap-tones of these ‘plates’ using a thumb-plane and scraper, then measure the tap tones using your home computer: you’ll need some kitchen scales too. This allows you to be more confident that your first or your next fiddle will sound excellent! Or perhaps you could also improve the quality of sound from a low-cost, poor sounding violin as I do!

This isn’t my work really. It’s using, summarising and building on the years of work others, the great names have done over the last 60 and more years. I have no problem with standing on the shoulders of others. I’m an experimental researcher by inclination and training: ‘try it!’ I say. And I love reading and learning what others have written. I hope you benefit.

Good tone: the search for the grail.

At the heart of getting good tone from a violin is matching the front and back plates, with just the right properties of stiffness and weight in both. Tap tones are a measure of the stiffness properties of the plates. What this method will do is show up the quality of the wood itself, especially the spruce of the front or belly. So don’t just use any old wood. Use good old wood.

By setting these tap tones to chosen frequencies, as well as matching them front and back, almost any factory violin can have its tone dramatically improved, whatever wood it is made from.

The tap-tone method outlined on this website allows you to choose the tone you get too. It could be a ‘student’ tone with easy bowing, or perhaps instead a ‘solo’ instrument tone with unforgiving or hard bowing, but very powerful, and suited to real solo work. My personal preference is for ‘chamber’ and ‘orchestral’ tone instruments somewhere between the two: easy to bow, and flexible in use, suited to an Irish pub session, a quartet or in a symphony orchestra.

Limitations: you need craftsmanship too

This however is not a cure to all human suffering. Much or even most of a violin’s quality of sound derives from just ‘good practice’ in its making. There is no substitute for proper, patient, practiced craftsmanship and artistry in the making and modification of an instrument. It should be, it must be a work of art! I cannot begin to teach any of that. I can only help with some of the science and engineering aspects. Go to a craftsman for craftsmanship, and set aside some years to do it.

Tuning the plates

Plate tuning can help make your first or your tenth violin a good instrument - a fine reward for 10’s of hours of work. And it is not at all difficult. I personally mostly use this method to improve the tone and playability of factory-made or damaged fiddles, such as ones with bad soundpost cracks.

Significantly, I have found a way of quickly measuring Mode 2 and Mode 5 frequencies of violin backs and the back’s weight, without removing the back from the bouts (sides and blocks). So all I do need to remove is the front (the belly) and the fingerboard of a factory fiddle to work on the back to set up its ‘stiffness factor’, and then I modify the front to match it. So get in touch with me if you want to know more.

Carving a brand new spruce front for an old, indifferent or damaged fiddle can also give you remarkable results: but you have to start with good new spruce though!

Arching and thicknesses

If you want to know what arching and thicknesses to use for the plates, have a look at this page. Then have a look at Acoustics for Violin Makers by Erik Jansson in “Chapter V: Vibration Properties of the Wood and Tuning of Violin Plates”. Here is just page 25 extracted from it with a scheme to gradually reduce thicknesses of plates in an appropriate way while keeping Modes 2 and 5 under control. This series of papers by Erik Jansson is a key reference work on acoustics and the violin: and it’s free! He used to work with Carleen M Hutchins (CAS) and really knows his stuff. Have a look on the links page too.

History: start at the beginning

Every journey begins with but a single step, and every organization begins with a single member. That’s me. My committee meetings always run without a hitch.

Well, I’ve always wanted a Stradivarius or Guarnerius violin, but somehow I can’t seem to muster that first £ million. I played a Guarnerius violin once, and it spoiled me: how could I, that bowing arm be making that fabulous sound? That sound, that’s a bit like a professional soloist on a CD? Well, with all the arrogance I could muster as a qualified engineer, I decided if I couldn’t buy one, I’d have to make one. And of course, I know that as soon as I get a Strad then my amateur scratchings will be instantly transformed into something truly wonderful ......

Carleen M Hutchins, and the CAS.

Over the years, trying to make some awful violins sound better, what I needed was a rationale to this mending and tinkering. So my long-suffering wife bought be the collected works of the CAS (Catgut Acoustical Society) for Christmas two years ago. A remarkably lady called Carleen Maley Hutchins co-founded the CAS nearly 50 years ago, and I remember her first article well: my mum showed it to me in the early 60’s when it was printed in Scientific American (Nov 1962). You can get back-copies if you do a web search. A later article by Carleen (about 1982) can be found here on a Russian website, which I’ve put into a .pdf file here. The excitement of that approach stayed with me.

Traditionally violin makers tune the front and back plates around an ‘F’ to ‘F sharp’ tap tone**, with the back plate a semitone or tone above the front. The many tap-tone methods has been around for well over a hundred years (see footnote) and probably very much longer. Unfortunately factory-made fiddles, all that many of us can afford, have never even heard of ‘tap tones’ or even suffered much care in manufacture. Indeed many of these fiddles have so much wood in the back that if burned they could heat a small home for an evening.

The role of the home computer

What has changed over the last 5 years is that the ubiquitous home computer (shown right), used with a cheap microphone, has made available to us methods for measuring tap tone frequencies quickly. It takes me a minute or so to measure the tap tones of a violin plate. Carleen would need perhaps an hour, and Signor Antonio Stradivari ? Well he needed a very well trained ear and maybe a a ‘standard’ wooden rod to tap for comparison. A good ear helps these days, but is not essential.

First I found that Carleen’s methods of adjusting the tap tones of front and back to an octave (1:2 ratio of Modes 2 and 5 frequencies in both) just did not produce really good fiddles: They were better, but still not very good. I think it’s partly because the wood for factory fiddles, especially the fronts, is not top, low density, prime-choice wood!

Makers can pay as much for the wood as some might pay for a violin outfit: Simeon Chambers has a good range of wood at reasonable prices. He suggests the light Englemann spruce for bellies, with a density (specific gravity) of 0.34 to 0.38, which is much less than than normal European spruce at 0.45.

Dr. Nigel Harris

Some 8 months ago I came across an article by Dr. Nigel Harris’s on the web that now seems to be the next step in the mysterious connection between the tap tones of a violin’s plates, its playability (the violin’s is ease of bowing), and a real quality and depth of sound. In addition, as Dr. Harris puts it: it can make a given tone reproducible, violin to violin!

Dr. Harris, who sells some seriously good (and pricey) violins, at Harris & Sheldon (violin.co.uk) links the plates’ Mode 5 (called the ring tone),  Mode 2 (the ‘X’ Mode), and now also the weight of plates front and back in a formula that yields what he calls the ‘Stiffness Factor’. His work on over 1000 violins shows that if the front and backs have a similar ‘stiffness factor’ then a good fiddle will result. It will sound good and similar to other fiddles with the same matched plate ‘stiffness factors’.

What I have done is broaden Dr. Harris’s work a little, combining Carleen’s work on Student /Amateur / Orchestral and Solo tones with Dr. Harris’s so that I can pick and choose what ‘kind’ of tone I want. On this website I give a method for applying the technique. I have verified that it works by modifying 8 violins of all types so far, but there’s some way to go yet.

What this is all about: making a £75 ($150) violin sound like a £1500 ($3000) violin

So this web site is all about just how to measure tap tones and how to apply Dr. Harris’s ‘plate stiffness factor’ formula either to help you make a new violin, or to modify an existing and poor-sounding £75 ($150) factory fiddle to get it to play and sound like a £1500 ($3000) violin.

Have a look at the various pages here. In particular, have a look at how to easily measure tap tones, and how to use them to get matching front and plates even when using less than the best spruce and maple. I’ll show too the various stages of how I modified some constructionally challenged instruments.

You can’t do much damage to a £30 ($60) violin: at worst it’s £30 of experience. Warning: but do not try this at home children, it can seriously damage your father’s favorite violin.

Feedback: tell me what you think, and tell me about your experiences.

Let me know what you think of this site and its contents: violin plate tuning seems to evoke strong emotions in luthiers ...... so let me know what you think: now ! It’s all work in progress, so I’ll include your comment (no promises though).

So please Email me, or comment here in my blog ......

PS: Amusingly, this website is also available in the Russian language, but I’m still looking for the Russian for “tinkerer”. Perhaps any native Russian speakers could help out here. It is also available in all the major world languages here at Google translation in  French, Spanish, German or Greek  ....

** F# is 370 Hz, F (natural) is 349.2 Hz, and E is 329.6 Hz. The reference here is to Ed. Heron-Allen’s book on violin making of 1885-6. Believe it or not he refers to Modes 2 and 5 and ‘nodal lines’ on p.133, and tells the reader how to visualise them using sand and a bow!  Yes, that’s from 123 years ago.