THE HARP

The single action harp in the Empire style was built in 1809 after the stamped sign “LYDIATT 1089  7” on the bell-crank block. It has 42 strings, running from Eb1 to d4. Total height 172 cm. The 8th pedal works for the shutters built in the body shell back.

The harp is signed “Sebastian Erard’s PATENT HARP   N 1224 / No.18. Great Marlborough StreetLONDON” engraved into the right hand mechanism plate. Some wooden parts carry the number “1233” while the pedals are stamped “1231”.

Pedalbox, base of pillar and capital are decorated with gilded stucco (compo) work. The capital shows busts on pedestals, ram’s heads, palm leaves and so forms a kind of Grecian artwork. Pillar is fluted. Varnish is black colour. The soundboard is decorated with 2 figures, printed on gilded paper as well as ornamented borders made in the same manner. The 5 shutters of the swell mechanism have each 1 figure, printed on gilded paper and surrounded with black colour.

DAMAGES

The neck is slightly damaged by worms. The soundboard is in acceptable condition, no large shrinking cracks, but forming a stomach in the bass area where some fibres are broken in the centre, resulting from unsuitable strings.

The shutters – built in the body shell back – are well, but two parchment bands are broken.

The stucco has some split-offs and a few parts are missing in the base of the pillar. The gilding is mostly rubbed or split off. Soundboard figures and shutter figures are rubbed or split off largely. The black varnish is partly split off.

The brass plates are dark by dirt. 5 adjusting bridges are broken, 1 pin is lost. The iron parts of the mechanism and the pedals are rusty.

One tuning peg is bent and broken.

THE  MAIN  RESTORATION  WORKS  2006

After dismantling the harp parts and mechanism, the surviving bass strings are measured: they might have been created for early Grecian double-action harps, as they show thin copper wire wound on a thin steel core, with a layer of silk in between. For my opinion they seem too strong for a single-action harp and I guess that silk-core strings would be more adequate.

Mechanism: The iron parts are cleaned with ammoniac 12% and rust had to be removed with vinegar acid 80%. The brass plates and small parts are cleaned with “Sigolin”. The plates are covered with a thin layer of Lascaux Acryl varnish. Three broken adjusting bridges are replaced (f’; a’; g”), two other bridges are soldered. A broken fork on disc g3 is soldered. The linen bandage of the pedal rods were in fine state, just needed to fix some endings of the linen bands, the threads are cleaned of rust with wire-brush. The cloth lining of the pillar is destroyed by moths. I replaced it with a new band on the inner side.

The pedals and also the springs are cleaned of rust with iron brush. Pedal leathers are renewed as well as some linings of the pedal box notches.

The tuning pegs are cleaned of rust with phosphor-acid 2,5%. One tuning peg has to be turned as new (bb°). A simple new tuning key was adapted.

Shoulder: I glued and secured the shoulder piece (cutaway) with additional screws from both sides.

The shutters were dismantled and put out of the body shell to replace two parchment bands.

Decoration: The figures on the shutters and on the soundboard and the border ornaments are secured and laid down with “Medium für Konsolidierung” of LASCAUX. The figures on the top two shutters are additionally covered with a thin layer of clear Lascaux Acryl varnish. The black colour is retouched.

I cleaned the black varnish (colour) with distillate water.

The soundboard black colour was now painted over with “Lascaux Studio” Acryl black colour to complete the whole surface and to surround clearly the figures silhouettes. Two layers of clear Lascaux Acryl varnish are put over the whole soundboard.

The body shell black is refreshed with VIOL cleaning oil.

The stucco parts are glued where they were loose, but no replacements were requested.

It was not requested to renew the gilding so I left it untouched.

The “throat” part (between mechanism and capital) was glued with a modern silicon-glue before; I cleaned it and then placed a small screw through the right hand plate to fix it without glue, such as seen in most other Erard harps of that period (actually no screw nor plug was found here…).

The stringing is now calculated to a tension of around 380 kp at a’ = 430 Hz (354kp at 415Hz). After the adjustment is done the intonation works well with 8th-comma temperament, but most of the adjusting bridges are at their top position; thus giving us a hint that even 6th-comma temperament might have been original. The stomach of the soundboard on the other hand is shortening most of the bass string length; these adjusting bridges are now situated very low.

The sound result is now warm, clear and transparent. The shutters allow changing of sound colour resonance but do not really act as a dynamic effect.

Tuning pitch at   a‘ = 430 Hz (415 Hz possible)          8th-comma temperament.

Beat Wolf , Schaffhausen, August 2006.