Template:FAQ:Space Optimisation (Linn Account) FAQ V3.2

The Linn Account and Space Optimisation

What should I do if I see an error message saying “Sorry, something went wrong”?

If you see this error message, please refresh the browser page. Once the browser page has refreshed:

1. click on your Linn account logo in the top right-hand corner,
2. click on Account Settings, and then
3. click on Start next to Send Activity.
   

This will record any further activity, until the browser page is next refreshed, for debugging purposes. Now attempt to recreate the issue that caused the error; if you are able to recreate the issue, please contact the Linn Service team, and our engineers will then be able to look into the issue with your recorded activity as reference.

Note that this issue may sometimes be related to an old Space Optimisation on your music system; turning off Space Optimisation in Linn Konfig and then refreshing the browser page in your Linn account may, in some cases, solve this issue.

How do I add my speakers to my music system?

Click on the Add Speakers button below the graphic of your music system; a dialog prompting you to provide the manufacturer and model of your speakers will appear.

Select the manufacturer and model of your speakers using the drop-down menus, then click on the Add button; if your speakers’ manufacturer or model does not appear in the drop-down menu, select Other. See §2.2 of the user guide for further information.

How do I add my subwoofer to my music system?

Subwoofers are currently unsupported within your Linn account; please use Linn Konfig to configure your music system.

How do I add my Exakt speakers to my music system?

Exakt speakers are currently unsupported within your Linn account; please use Linn Konfig to configure your music system.

How do I add my surround speakers to my music system?

Surround speakers are currently unsupported within your Linn account; please use Linn Konfig to configure your music system.

How is the new version of Space Optimisation different?

The new version of Space Optimisation uses highly sophisticated acoustic modelling to model the interactions between your speakers and room; this acoustic modelling is based on the finite-difference time-domain method. A simple two-dimensional analogy to this method of acoustic modelling is of a fishing net laid over a pond; each knot in the net defines a discrete measurement location, so that when a stone is thrown into the pond we can track the resulting ripple by measuring its height at each knot. The spatial discretisation employed by this method of acoustic modelling allows the new version of Space Optimisation to correctly consider the effects of: non-rectangular rooms; the placement of features like doors and windows; and the location and rotation of your speakers. Furthermore, the time-domain formulation of this method of acoustic modelling means that the new version of Space Optimisation is now able to reduce both the energy and decay time of any artificial distortions caused by the interactions between your speakers and room, resulting in both a flat frequency response and a uniform decay time. Finally, the new version of Space Optimisation has been designed to give a better balance of low- and mid-frequency energy.

Why does Space Optimisation not use a microphone measurement?

The aim of Space Optimisation is to remove the effects of your room, in order to uncover the unique acoustic characteristics of your speakers; after all, this is what you fell in love with when buying your speakers. In order to do this, Space Optimisation needs to understand both the interactions between your speakers and room and the unique acoustic characteristics of your speakers; the unique acoustic characteristics of your speakers are then subtracted from the interactions between your speakers and room, leaving only the effects of your room.

An acoustic measurement of the interactions between your speakers and room can have many sources of error which may affect the accuracy and repeat-ability of the measurement, including: the choice of measurement stimulus, such as MLS or a log chirp; external noise, such as traffic noise and vibration; quality and calibration of the microphone, which can introduce distortion; and the microphone location, which can be sensitive to within a few centimetres. The use of acoustic modelling removes these sources of error: the model can apply an ideal impulse as stimulus; the modelling domain is free from noise; the model can use an ideal microphone; and the listening location is well-defined. It can thus be seen that acoustic modelling has a clear advantage over acoustic measurement in understanding the interactions between your speaker and room.

The unique acoustic characteristics of your speakers depend on many factors, including: the shape and size of the drive units and ports; the constructive and destructive interference between the drive units, ports and any cabinet-edge diffraction sources; and the angle between the listening location and your speakers. Therefore, a simple on-axis anechoic measurement of your speakers is insufficient information; what is actually required is an anechoic measurement with your speakers in the exact same configuration as you have them in your home. While some manufacturers do publish anechoic measurements of their speakers, both on- and off-axis, it is extremely unlikely that they will have performed an anechoic measurement of your speakers in the exact same configuration as you have them in your home. The acoustic modelling of such a scenario is, however, straightforward; the model can simply turn your room into an anechoic chamber to obtain the unique acoustic characteristics of your speakers in the exact same configuration as you have them in your home. It can thus be seen that acoustic modelling once again has a clear advantage over acoustic measurement in understanding the unique acoustic characteristics of your speakers.

From the above, it is clear that acoustic modelling is the best approach to Space Optimisation.

How long should an optimisation take to calculate?

The calculation time of an optimisation will depend on your room and speakers, with large rooms containing multiple speakers taking longer to calculate than small rooms containing few speakers; optimisation calculations may take anywhere between four and twenty minutes, with a typical optimisation calculation taking around five minutes. See §1.2.3 of the user guide for further information.

The processing time is governed by the processing speed available on the Web services. The expected calculation times are:

Small room (up to 25m²) with small speaker (up to 3 drive units): Typically 4-5minutes

Medium room (25m² - 100m²) with medium speaker (up to 4 drive units): Typically 5-8minutes

Large room (More than 100m²) with a large speaker (4 or more drive units): Typically 8-20minute

Note that if your optimisation calculation takes longer than expected this may be due to an issue where messages from the cloud are failing to reach your browser; refreshing the browser page <f5> or SHFT<f5>, in your Linn account should solve this issue.

How do I apply an optimisation to my music system?

Any optimisation may be applied to your music system by clicking on the radio button next to its name, in the list of optimisations below the Optimisations heading under the Space tab; note that application of an optimisation does not require a recalculation. See §2.3.4 of the user guide] for further information.

How do I see what filters the optimisation is applying?

Bass and treble shelves are currently unsupported within your Linn account.

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Room steps 2.1 Why should I ignore small geometrical features with dimensions less than 10 cm?

Due to the spatial discretisation employed by the method of acoustic modelling used by Space Optimisation small geometrical features with dimensions less than 10 cm can cause inaccuracies in the model. Consid-ering again the analogy of a fishing net laid over a pond, we can imagine a small island in the pond: if this small island lies between knots it will be ignored by our discrete measurements; however, if this small island lies on a knot it will invalidate our measurement at this knot, causing an error which would propagate away from the small island.

2.2 Why should I ignore hard furnishings?

Where rooms contain hard furnishings it is recommended to ignore these; at low frequencies such hard furnishings are usually almost acoustically transparent. While certain hard furnishings, such as cupboards and wardrobes, may add extra resonances of their own, the effects of such resonances are usually highly localised.

2.3 How do I add a free-standing wall?

Free-standing walls are currently unsupported. However, where rooms contain free-standing walls it is rec-ommended to ignore these; at low frequencies such free-standing walls are usually almost acoustically trans-parent. See §3.4.2 of the user guide for further information.

2.4 How do I enter my open plan room?

When entering an open plan room all rooms open to the main listening room should be entered; antecham-bers and additional cavities will add extra resonances and affect decay times. See §2.3.1 of the user guide for further information.

2.5 How do I enter the length of a wall?

In the Floor Plan step you may select any corner with a click, and drag it to any desired location to define the length of a wall. Manual input by typing the length of the wall is not supported, as this would cause a knock-on effect around the other walls of your room as corners are shifted to accommodate the new length. See §2.3.1 of the user guide for further information.

2.6 Why is the minimum grid size on the Floor Plan step 1 cm?

Space Optimisation considers only frequencies below 80 Hz; this corresponds to a wavelength of around 4

m. A grid size of 1 cm allows for accurate entering of wall lengths to 5 mm, which gives an accuracy of around 0.1 % at 80 Hz.

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2.7 How do I find out the construction materials of my room?

The construction materials of your room can be found from the building plans. If you cannot obtain the building plans, simply knock on each surface; a hollow sound would suggest Suspended or Partition con-struction, whereas a sharp sound would suggest Concrete construction. In order of a hollow to a sharp sound, the common construction materials of walls are Partition, Drywall, and Concrete. Similarly, the common construction materials of floors are Suspended Floor and Concrete, and of ceilings are Suspended Ceiling and Concrete. See §2.3.1 of the user guide for further information.

2.8 How do I measure my room features?

When measuring room features only the feature itself, and not any trimmings, should be measured: for a door only the door panel should be measured, and not the door frame; for a window only the window pane should be measured, and not the casement. Any non-rectangular features, such as circular windows, should be modelled as a rectangular feature of equal area.

2.9 Why should I ignore soft furnishings and decorations?

Where rooms contain soft furnishings, such as carpets and curtains, and any decorations, such as paintings and mirrors, it is recommended to ignore these; at low frequencies such soft furnishings and decorations are acoustically transparent.

2.10 Why do features disappear when I change my room dimensions?

When features have been added to a room, and subsequent changes are made to the room dimensions, the features on any affected surfaces will be removed; since the surface dimensions have changed, there is no guarantee that the features on this surface remain valid, and so they are removed. The setup process of Space Optimisation has been designed in a step-based manner; you should complete each step before moving on to the next.

2.11 How do I add floor and ceiling features?

Floor and ceiling features are currently unsupported, and so an approximation procedure must be adopted; the presence of floor or ceiling features, such as trapdoors or skylights, will tend to increase the average absorption of the floor or ceiling, therefore the absorption of the floor or ceiling construction material should be increased in the Absorption step. See §3.2.1 of the user guide for further information.