Acousticians' Guild

The Acousticians' Guild is the chartered body of the Tower responsible for the measuring, tempering, and licensing of sound, and for the supervision of the Lucid Static environment within any registered Lucid Vault. It is among the oldest guilds of the middle floors and among the least popular, a reputation it has never sought to correct. Its seat is at Resonance Hall, on the floor the Guild refers to in its instruments only as the Tuned Floor; the number of that floor appears on no map issued by the Guild of Formal Cartographers.

Guild membership is by audition and by silence, in that order. The audition is brief. The silence lasts one year and one day, and the candidate is expected to fill it.

Charter and Concordance basis

The Guild's authority derives principally from Fourth Concordance, Annex 2, which grants it "sole competence over all sounds occurring at a height, and over the licit absence of such sounds." The phrasing has been litigated at least nine times, most recently in a dispute with the Guild of Groundskeepers over whether a stair may be said to occur at a height when it is being descended quickly.

The Guild is named in the Twelfth Concordance as a party to the triennial review of Lucid Vault operations conducted at Vault Place, jointly with the Guild of Oneirology. The two guilds maintain a working relationship conducted almost entirely in writing, and largely in disagreement.

Lucid Bronze and instrument fabrication

The Guild's principal material is Lucid Bronze, which it does not manufacture and does not permit others to work. Fabrication is carried out under licence to the Glasswrights' Guild, designated GL-Beta-7 in the registry of the Inter-Guild Logistical Network Guild, whose craftsmen cast the rough bells and tubes that the Acousticians subsequently tune, reject, or — in the case of one unlucky batch in the winter of the year recorded as 1147 — return with a note reading only "these are the wrong shape."

Finished instruments are held in the Held-Note Register, a bound inventory kept in duplicate. The Register records every instrument by pitch, mass, and reason for retention. The reason is frequently "none given."

Monitoring of the Lucid Vault

Within a Lucid Vault, the Guild's task is to ensure that the Lucid Static remains in a state of arrested flow — neither still nor running, but held at the threshold at which it may be observed without being spent. This is achieved by continuous sounding of a reference tone from a fixed array, and by the attendance of at least two Guild monitors at all times, who are forbidden to speak to one another for the duration of the shift.

"The Static is not to be woken, and it is not to be put to sleep. It is to be kept at the edge of hearing, where it may be counted."

— Second Concordance, Annex 11, clause 4

The prohibition on speech is practical rather than ceremonial. On two recorded occasions, monitors who conversed during a shift produced a deviation in the reference tone sufficient to require the Vault's closure for eleven days, and in one case the replacement of the entire array. The Guild does not discuss the second occasion.

Governance and the Silent Divan

Senior members of the Guild sit on the Silent Divan, the council through which governance of the Sultanate is exercised. The Guild's representation on the Divan is fixed at three seats, though the Seating Schedule of the Divan has listed four Acousticians at every count since the schedule's last recension, and no correction has ever been issued. The Margin Commentators Guild has noted the discrepancy in three separate commentaries; the Reflector Guild has declined to comment on the ground that the question is not reflective.

Internal discipline is administered by the Office of the Held Note, which hears complaints and issues findings in the form of a single sustained tone transcribed into notation. A finding of censure is written as a minor second. Expulsion is not written at all.

The Tuning Dispute

The Guild's longest-running disagreement concerns the Standard Pitch Question: whether the Tower's reference pitch should be fixed at the value established by the Third Concordance or permitted to drift as the upper floors have drifted. The Guild of Harmonic Theorists holds that pitch is a property of the Tower at large and cannot be legislated. The Acousticians hold that pitch is a property of an instrument and can be legislated precisely.

The matter was referred to the Constructivist Guild in the year recorded as 1189, which returned the opinion that a pitch not fixed is not a pitch but a tendency. The Acousticians adopted the opinion as precedent. The Harmonic Theorists have never accepted it, and continue to tune to a value the Acousticians describe in correspondence as "notional."

In 1204 the Guild issued a general instruction that all bells rung on the lower floors be struck at the shoulder rather than the lip, on the finding that shoulder-struck bells carry further without being heard. Compliance is not monitored.

Relations with other bodies

The Guild's practical needs — candles, sealed tubes, the movement of monitors between floors — are met through the Inter-Guild Logistical Network Guild, whose schedules the Acousticians describe as "audible" when they are on time and decline to describe otherwise. Candidates for the silence-year are housed and fed by arrangement with the Scribes' Guild of the Middle Floors, an arrangement the Scribes have twice attempted to renegotiate and twice withdrawn after a single meeting.

The Guild maintains no public register of members. It has never stated how many Acousticians there are, and the figure given in the Concordance of Registers — "sufficient" — is the only figure in that volume not accompanied by a numeral.