1. Method of transmitting audio signals between a transmitter and at least one receiver, comprising the steps of:
(a) resolving an audio signal into a number n of spectral components through a number n of frequency selective filters;
(b) storing the resolved audio signals in a two-dimensional array having a multiplicity of fields, and wherein frequency and time are stored as dimensions of the array and the amplitude as a particular value to be entered in a field within the multiplicity of fields of the array;
(c) combining each field of the multiplicity of fields into a field group wherein there are a plurality of field groups formed from the multiplicity of fields, and each field group is formed from at least three adjacent fields;
(d) assigning a priority to each group of the plurality of field groups, the priority of one group over another group becoming greater based upon at least the function of the greater the amplitude differences of the values of a group
(e) sorting the field groups of said array with the aid of their priority value;
(f) storing andor transmitting the groups to the at least one receiver in the sequence of their priority; and
(g) transmitting said audio signals at low transmission bandwidths so as to minimize transmission losses.
2. Method as claimed in claim 1, characterized in that the entire audio signal exists as an audio file and is processed and transmitted in its entirety.
3. Method as claimed in claim 1, characterized in that only a portion of the audio signal is processed and transmitted in each instance.
4. Method as claimed in claim 1, characterized in that the audio signal is resolved into its spectral components by means of FFT.
5. Method as claimed in claim 1, characterized in that in the receiver the groups transmitted in accordance with their priority are assigned to a corresponding array, the values of the array still to be transmitted being calculated through interpolation from the already available values.
6. Method as claimed in claim 1, characterized in that from the existing and calculated values in the receiver an electric signal is generated and converted into an audio signal.
7. The method of claim 1, wherein said assigning step further comprises assigning a priority to each group of the plurality of field groups, the priority of one group over another group becoming greater based upon utilization of one or more functions selected from the group comprising:
(i) the greater the amplitudes of the group’s values; andor
(ii) the closer the group is to the current time.
8. The method of claim 1, wherein said transmission step further comprises transmitting individual frequency components, wherein said individual frequency components further comprise amplitudes and phases.
9. Method of transmitting signals between a transmitter and at least one receiver, comprising the steps of:
(a) resolving a signal into a number n of spectral components though a number n of frequency selective filters;
(b) storing the resolved signals in a two-dimensional array having a multiplicity of fields, and wherein frequency and time are stored as dimensions of the array and the amplitude as a particular value to be entered in a field within the multiplicity of fields of the array;
(c) combining each field of the multiplicity of fields into a field group wherein there are a plurality of field groups formed from the multiplicity of fields, and each field group is formed from at least thee adjacent fields;
(d) assigning a priority to each group of the plurality of field groups, the priority of one group over another group becoming greater based upon at least the function of the greater the amplitude differences of the values of a group;
(e) sorting the field groups of said array with the aid of their priority value;
(f) storing andor transmitting the groups to the at least one receiver in the sequence of their priority; and
(g) transmitting said signals at low transmission bandwidths so as to minimize transmission losses.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A substrate for an additive manufacturing process, the substrate having a build surface for fusing to a part being formed on the substrate by the additive manufacturing process, wherein the substrate is configured to provide relatively high stiffness in a direction substantially perpendicular to the build surface, whilst having a low longitudinal stiffness in the plane of the build surface.
2. A substrate according to claim 1, having an upper portion nearest the build surface and a lower portion, wherein the upper portion includes a different construction andor material to that of the lower portion.
3. A substrate for an additive manufacturing process, the substrate having a build surface for fusing to a part being formed on the substrate by the additive manufacturing process, wherein the substrate has an upper portion nearest the build surface and a lower portion, and wherein the upper portion includes an array of protrusions with their longitudinal axis aligned substantially perpendicular to the build surface.
4. A substrate according to claim 3, wherein tops of the protrusions provide at least a portion of the build surface.
5. A substrate according to claim 3, wherein bases of the protrusions are integrally formed with the lower portion of the substrate.
6. A substrate according to claim 3, wherein the protrusions are slender, preferably having an aspect ratio of at least 3.
7. A substrate according to claim 3, wherein the protrusions each have straight sides substantially perpendicular to the build surface.
8. A substrate according to claim 3, wherein the protrusions each have a taper of increasing cross section towards the build surface.
9. A substrate according to claim 3, wherein the substrate is a monolith.
10. A substrate according to claim 3, wherein a gap between adjacent protrusions is filled by a material dissimilar to that of the protrusions.
11. A substrate for an additive manufacturing process, the substrate having a build surface for fusing to a part being formed on the substrate by the additive manufacturing process, and one or more slits extending from the build surface through part of the thickness of the substrate.
12. A substrate according to claim 11, wherein the slits are provided in an upper portion of the substrate, and a lower portion of the substrate is substantially solid.
13. A substrate according to claim 11, wherein the slits form a grid.
14. A substrate according to claim 13, wherein the build surface is substantially rectangular and the grid is aligned substantially with an edge or a diagonal of the build surface.
15. A substrate according to claim 11, wherein the slits are provided on only a portion of the build surface.
16. A substrate according to claim 11, wherein the slits have a substantially uniform width.
17. A substrate according to claim 11, wherein the substrate is a monolith.
18. A substrate according to claim 11, wherein the base of each slit has a radius corner.
19. A substrate for an additive manufacturing process, the substrate having a build surface for fusing to a part being formed on the substrate by the additive manufacturing process, wherein the substrate has an upper portion nearest the build surface and a lower portion, and wherein the upper portion includes a different material to that of the lower portion.
20. A substrate according to claim 19, wherein the lower portion has a higher stiffness than the upper portion.
21. A substrate according to claim 19, wherein the upper portion includes a material of high ductility and low yield strength as compared with the material of the part intended to be fused to it during the additive manufacturing process.
22. A substrate according to claim 19, wherein the upper portion includes a includes a material of low elastic modulus and high strain to failure as compared with the material of the part intended to be fused to it during the additive manufacturing process.
23. A substrate according to claim 19 wherein the upper portion includes a material that is weldable with the material of the part intended to be fused to it during the additive manufacturing process.
24. A substrate according to claim 1, wherein the substrate is re-useable for building successive part(s) by the additive manufacturing process.
25. A substrate according to claim 24, wherein a top layer of the substrate is removed after each build to redefine the build surface.
26. A system for creating a part by an additive manufacturing process, the system including a substrate in accordance with claim 1.
27. A system according to claim 26, configured to create the part layer by layer.
28. A system according to claim 27, configured to create the part by selectively sintering successive powder layers.
29. A method of forming a substrate for an additive manufacturing process, comprising providing a plate, and cutting one or more slits extending from the upper surface of the plate through part of the thickness of the plate.
30. A method according to claim 29, wherein the slits are cut by electrical discharge machining (EDM) or by a laser.
31. A method of forming a substrate for an additive manufacturing process, comprising using an additive manufacturing process to form a substrate having an upper portion and a lower portion, wherein the upper portion includes an array of upstanding protrusions.
32. Use of a system according to claim 26 for creating a part by an additive manufacturing process.