Advantages of the construction and materials used in the PETROF IV Grand Piano
Rim

Petrof original. Inner frame is laminated from 9 layers of solid beech and birch lamels. Side wall is laminated from birch plywood lamels. Total thickness of side wall of piano is 5,8 mm. The rim is produced with highest exactness at "CNC machine".
The solid construction of the rim of P IV grand piano ensures high and long term tuning stability and action regulation as well as sound board crown stability which is a prerequisite for perfect performance.

The rim is reinforced by 3 massive spruce posts. The connection is provided by fish-tail and beech dowels. The frame posts are produced with high exactness at "CNC machine".
The frame posts provide a high contour stability of the frame, tuning stability and regulation.

Petrof original. Solid beech core, solid alder outer lining, gabon counter veneer, outer decorative thin veneer.
The robust construction of the legs ensures high stability of the instrument whilst being played.

Czech producer. Gray cast iron, hand worked, drilled at "CNC machine", lacquered.
Precise drilling means exact length of strings and creates good conditions for their optimal oscillation and creation of an exact tone.

Petrof original. Solid brass, polished, lacquered.
Hardware fittings are corrosion resistant, therefore they do not require any maintenance. It is fully comparable to fittings used in the finest world's grand pianos.

Special beech plywood type Multiplex. Original veneer thickness 2 mm compressed to the density 800 - 850 kg/m3 (= 6 veneer layers/cm). High moisture resistant glue.
The pinblock in this grand pianos has a high resistance against atmospheric changes (e.g. humidity). It provides equal torque of tuning pins, which results in a particularly high tuning stability.

Petrof original. The soundboard is made from European spruce. It has a spheric crown and is shaped into wedge block. Thickness 9 mm in the center, tapered to 7 mm (in bass and front part).
Traditionally shaped sound board gives high acoustic performance in all frequencies of the whole range. Its construction greatly contributes to generating the typical tone of PETROF grand pianos.

Petrof original. Treble - solid beech, hornbeam cap, genuine ebony descant cap. Bass - solid beech, hornbeam cap (with a foot bridge). Bridges are blackened by black PUR finish. Hand notched and bored.
The construction of the bridges and materials are comparable in quality with the highest class of standard grand piano bridges. The hornbeam cap of treble bridge supports better transmission of high frequencies onto the sound board. The foot bridge of bass bridge enables an oscillation with bigger amplitude, it improves its sound ability.
The construction and materials used in the P IV grand piano support the creation of typical tone of PETROF instruments and give sufficient acoustic performance to the grand piano.

Steel wire Mapes USA, Röslau Germany. Copper Degen Germany. Longest string 1410 mm. Steel, nickeled.
Strings used in the P IV grand piano are made from string wire of the world's finest quality. The tuning pins are of the highest quality, corrosion resistant and fully comparable to the best marks of grand pianos.

Abel Germany, walnut or hornbeam mouldings. Abel Premium under felt and top felt.
Hammer heads Abel, which are fitted in this grand piano, are some of the best worldwide. They enable the player to get a great variety of tones.

Petrof, hornbeam heads. Felt Laoureux France.
The felt, manufactured by French company Laoureux, is a guarantee of the highest quality proven by generations.

Petrof original action. Wippen rail aluminum. Hammer rail aluminum. Hornbeam action parts.
The PETROF action is quick and with good repetition. Specifically profiled aluminum action rails are very stable also in changing humidity. The action enables the P IV grand piano to be played confidently, even technically demanding passages, and to have full control of creating tones.

Petrof original. The keys are from European spruce. White and black acrylic tops - Polyplex Sweden. Individually balanced keys.
The P IV grand piano has keys of European origin, each keys individually balanced. The quality is proved by more than 140 years of production tradition.

Petrof original. Spruce sandwich board, beech veneered. Solid beech insert in lyre and legs zone. Thickness 47 mm. The key bed is reinforced by beech from below.
Robust key bed of the P IV grand piano is of the same construction as in master concert instruments. It ensures regulation stability of this grand piano's action as well as stability of the whole instrument. It provides a certitude to a playing pianist.

3 pedals, solid brass.
The construction, materials and function of P IV's pedals are comparable in quality with the highest class pianos' pedal mechanisms.