Tuning and Voicing

Before I start to tune any flute, I decide on what block and flue configuration would probably be best. This is usually influenced by the type of voice the flute is to have. I cannot stress enough that the block design makes a huge difference to how the flute sounds. As you can see from the Blocks and Artwork page, I have a range of block designs. Some are chimney fronted (useful for new players as the chimney helps prevent the fundamental note from breaking to the octave above if the flute is blown too hard; but note chimneys do make the flute breathier), flat fronted or arched (give a much clearer, crisper, windless voice to the flute; useful for recording flutes), and some have a slipper ramp in the base to focus the air better and work with a grooved flue floor to give a whole range of voices to one flute. No, I am not giving any more details - trade secret of organ pipe makers! Suffice it to say I have 12 different block styles for tuning alone.

Having chosen a tuning block, once I'm happy that the sound is falling within, or extremely close to, the final one, only then do I cut the flute to its real fundamental length (or its apparent length if it is to have tuning holes) using a special jig on the bandsaw. Now, important point: I cut the flute so it is very slightly (about 10 cents) sharp. This is because as you add holes to the flute, you are adding small amounts of extra air column length. The depth of each hole adds slightly, but very significantly, to the total figure. This is not so evident on thin walled or bass flutes, but can be a major factor on normal 5.5 mm (7/32 inch) walled flutes particularly the lower keyed flutes with narrower bore diameters. I therefore tune with decreasing sharpness as I go up the holes, knowing that by the time I have finished all the holes should be at or close to the pitch I want them. The fine tuning comes later once the proper block has been made.

I tune my flutes to play on key at between 65-75 C (unless requested otherwise). I use a Korg CA-30 chromatic tuner, and for concert flutes I also check the tuning against keyboards. I'm also pedantic..I check the actual final length of the flute against the calculation of what it should be; this way I get an idea of how accurate the bore size is, which has a bearing on subsequent tuning calculations. Finally, I check the wall thickness along the bore length using a special jig, as this too greatly affects tuning and playing hole placement.

Having decided at the initial design stage on what key I want, major or minor, how many (if any) tuning holes there will be, whether there's to be 5, 6 or 7 playing holes, and what their diameter should be, this stage puts it into practice and is all maths. As I said, I'm pedantic..until a couple of years ago I would derive the hole placement positions by a new set of calculations for each new flute; I'd come a cropper too many times trying to mark hole positions across from an existing flute to a new one!
Maths, maths and more maths...
The calculations themselves are based on the formulae given by Lew Paxton Price in his invaluable books 'Secrets of the Flute' and 'More Secretsof the Flute.' However, I have taken his equations a little further such that I can derive hole placement positions by using a series of base equations to generate quadratic equations, for which there are some good, free, little computer programs around on the internet. Once I have the measurements for the flute I have just made, it only takes about 15 minutes to generate and mark the first hole position. One major plus doing it this way is that I can take anyone's hand graphs (which show me finger length, palm width, pad size, occlusions - where the tip of one finger bends towards another - reach distances between fingers etc), do the maths on them, and put the playing holes exactly where their fingers fall - to me this is a key part of making any flute.



WORKSHOP
s
Home  g
g
s
Introduction  g
g
s
The Flutes  g
g
s
Hear the Flutes  g
g
s
Blocks and Artwork  g
g
s
Available Flutes  g
g
s
Workshop  g
g
s
Contact & Ordering  g
g
s
Thanks & Links  g
g

That said, I have now made over 300 flutes and have the maths, details and all the measurements for each one, plus the handprints for the people those flutes were made to fit. I can nowadays usually go back to these 'creation sheets' and see what worked, what could have been moved a little one way or another, and can work out where the first hole should be based on this and the measurements of the flute I am making and on the customer's handscan data.

Once the first hole (be it playing or tuning) is marked up on the flute, I drill a 3mm pilot, open this out to about 5mm with a tungsten carbide conical grinding tip on a Dremel, clean the hole and then check the note. From there on, I follow the traditional route and burn the hole out to achieve the desired note. I use medium and large Ahoken Flutemaker's Burning sticks heated with a blowtorch. I far prefer burning because it's much more subtle than a drill or Dremel and there's a scope to make fractional adjustments to a note that you cannot otherwise easily achieve, including undercutting to open up a hole without widening its top diameter. Also, the aroma of the burned wood stays with the flute for a very long time, and is one of the sweetest I know. The downside is waiting for the air in the flute to cool betwen burns, as hot air flies much faster through a flute and can give a pitch reading that is misleadingly sharp.


How not to tune a flute!

Wrong! I keep my first disastrous solo attempt at tuning over the workshop door to remind me how important the calculation process is and not to shortcut it.

I usually aim for (and have calculated for) the playing hole to end up between 1/4" (6mm) and 5/16" (8mm) diameter for a normal adult midkey flute. When the first hole has been burned, I will re-check against the calculations, see where the maths or previous flute creation sheet says the next hole should be and drill and burn that one. I would stress here that I do sometimes make intuitive adjustments to the spacing of the playing holes if, for example, the maths says the centre of the next hole should be 32mm away, but I'm fairly sure it needs to be a little closer to get the hole the right diameter for the client's hand. The rule is: the further down the barrel (towards the foot) the bigger a hole must be to achieve any given note; conversely, to produce the same note higher up the barrel would need a smaller hole. Playing hole size is very much a player's preference. I have seen some flutes with holes big enough to lose a finger in, and others where the holes are barely bigger than 1/8". Always remember, small holes give a poorer tone, the larger the hole the better (up to a point!)

up from the foot of bass flutes is usually the one that needs this. The other trick I use when I have to overcome large inter-hole distances (for example where a scale needs a three or four semitone shift between adjacent holes) is using variable wall thickness. I am not going to give any more away, except to say that if you deepen a hole by say 6 to 8 mm it's pitch goes down half a semitone... see the Yew pentatonic mode 5 flute on the Air Spirit gallery page.

Having tuned the flute, I'll carefully sand (400 and 600 Grit) around the newly burned holes and make sure the holes are clean edged and walled. I then go back and check the voicing and do any adjustments necessary before putting the flute to one side to settle for at least two days. After that, I then re-check it and make any fine adjustments to the tuning before moving on to decoration and finishing.


Playing holes
Right! Good-sized burned playing holes

Voicing a flute starts in the making of it. I have several specially designed ramp, channel, SAC vent and fipple designs which allow for very quiet flutes, very loud ones, or ones which can have both a flat bottomed block or a channelled block put on them for wide tonal ranges - the secrets for these designs will stay just that! The actual voice box mechanics can be very complicated in order to get the desired end result in terms of sound, tone, air flow, responsiveness etc. All SVF flutes are designed as 'clear-note' flutes, with a minimum of breathiness - although this can be built in if needed! But note: a breathy flute has character while a windy flute is often weak and rough sounding; the two are NOT the same! Once tuned, the final voicing of an assembled flute, that is the incremental filing, sanding, shaping of the fipple edge, sound hole and flue, and refinement of the block design, can be very quick or (more often) take hours or days. I cannot offer advice here - it's a personal choice, but I make the decision on how I want the flute to sound (clear, breathy, sharp, mellow etc.) and do most of the voicing work at this point.


Ahoken flute burning sticks
Tuning tools

I will at some point put up a separate page on voicing, since I have spent a lot of time studying organ pipe voicing, and now sometimes use 'nicking' or v-shaped score marks on the flue channel of bass flutes to give a really rich, resonant, earthy tone to them. However, this technique requires precision in the shape and angle of the cuts, the depth of the cuts, and their length and position; it's not for the faint-hearted, as if you get it wrong the flute is ruined!
 


Wood - choosing, preparing and sectioning
Cutting and routing the blank
Fipples, voice boxes and flues
Sanding, glueing and shaping
Finishing, Artwork and Blocks


 


I have deliberately NOT gone into the maths of tuning. If you want further details, please feel free to contact me. I am well aware it is possible to take this to 'nerd' level, and that comparative marking off a sister flute can, and often does, work well enough. However, I make flutes in such a way now that I'm almost always making one-offs, so do not run a batch of similar flutes off at one go. I have also omitted some of the more advanced points such as sometimes tuning the playing holes slightly sharp to compensate for the flattening which can occur when the hole above is burned.

Click on images to enlarge them in a new pop-up window.
 The Owlhouse • Milford • Surrey • UK • dc@secondvoiceflutes.co.uk

© Second Voice Flutes 2018