I brought one of theses a few years ago and never fitted it and then I mislaid it and while cleaning out a cupboard I found it 
I have hunted for this a few times as member Pab wanted to take off my hands and I dont think theses are available any more.
So if anyones interested let me know but Pab must get first refusal as I did promise it to him a few years back
All information on fitting can be found on the link below, also if you do some searching on the owners club you should find some further information.
How about £50 posted, im open to any offers
http://www.r75-parts.de/en/sle/index.php
In most cases Rover 75 owners complain about weak bass performance of their Symphony/Alpine radio. They wish more dynamics and power especially at low frequencies. SLE is a microprocessor module which is installed into the radio unit and significantly enhances the sound.The SLE module is suitable for all Rover 75 Symphony audio systems (sometimes called 'Alpine') with or without installed Lo-Line navigation system. If you have the Harman & Kardon premium audio system you may experience even more sound improvement because of the additional amplifier and subwoofer.The reason for poor sound are neither the eight loudspeakers (rated as being of good quality), nor the preamps or poweramps (4x 30W)used within the radio system. Even turning the bass settings to the maximum value of +9 won't bring the desired results.Like many high quality car radios, even the Symphony's audio processor has a built-in so called'Loudness' function. Unfortunately this function can not be activated because of missing software support and some missing electronic components. The loudness function amplifies lower frequencies at low and midrange volumes. Result is a dramatic improvement of sound dynamics especially in car environments.The Symphony Loudness Enabler module complements the radio electronics with some parts needed for full loudness functionality. Moreover the microprocessor attaches to the internal radio data communication and activates loudness if desired. Those changes to the data communication are not permanent and have to be performed every time some sound settings are changed by the user - not to mix up with a normal programming device which is removed after use.There are no changes made to the original radio control software. If Symphony Loudness Enableris removed from the radio circuit board, its original condition will be automatically restored.All advantages at a glance:no expensive power amps and/or equalizers necessary,no timeconsuming, expensive and awkward cabling,no speaker change,no change to the car electronics - only radio has to be removed and opened,reversible, i.e. the original state of your radio can be restored at any time just by removing the SLE module,SLE can be enabled or disabled by the 'PHONE' key on your radio. On any Symphony this key has no function but if it will be used in the future, SLE doesn't disturb its functionality.The operational state of SLE is stored and doesn't have to be set after turning ignition off and on,SLE is installed into the radio case, invisible from outside,no change to another radio (DIN-case) needed; the pleasant Rover 75 dashboard optics is left untouchedinstallation procedure takes about 30-45 minutes
I have hunted for this a few times as member Pab wanted to take off my hands and I dont think theses are available any more. So if anyones interested let me know but Pab must get first refusal as I did promise it to him a few years back
All information on fitting can be found on the link below, also if you do some searching on the owners club you should find some further information.
How about £50 posted, im open to any offers
http://www.r75-parts.de/en/sle/index.php
In most cases Rover 75 owners complain about weak bass performance of their Symphony/Alpine radio. They wish more dynamics and power especially at low frequencies. SLE is a microprocessor module which is installed into the radio unit and significantly enhances the sound.The SLE module is suitable for all Rover 75 Symphony audio systems (sometimes called 'Alpine') with or without installed Lo-Line navigation system. If you have the Harman & Kardon premium audio system you may experience even more sound improvement because of the additional amplifier and subwoofer.The reason for poor sound are neither the eight loudspeakers (rated as being of good quality), nor the preamps or poweramps (4x 30W)used within the radio system. Even turning the bass settings to the maximum value of +9 won't bring the desired results.Like many high quality car radios, even the Symphony's audio processor has a built-in so called'Loudness' function. Unfortunately this function can not be activated because of missing software support and some missing electronic components. The loudness function amplifies lower frequencies at low and midrange volumes. Result is a dramatic improvement of sound dynamics especially in car environments.The Symphony Loudness Enabler module complements the radio electronics with some parts needed for full loudness functionality. Moreover the microprocessor attaches to the internal radio data communication and activates loudness if desired. Those changes to the data communication are not permanent and have to be performed every time some sound settings are changed by the user - not to mix up with a normal programming device which is removed after use.There are no changes made to the original radio control software. If Symphony Loudness Enableris removed from the radio circuit board, its original condition will be automatically restored.All advantages at a glance:no expensive power amps and/or equalizers necessary,no timeconsuming, expensive and awkward cabling,no speaker change,no change to the car electronics - only radio has to be removed and opened,reversible, i.e. the original state of your radio can be restored at any time just by removing the SLE module,SLE can be enabled or disabled by the 'PHONE' key on your radio. On any Symphony this key has no function but if it will be used in the future, SLE doesn't disturb its functionality.The operational state of SLE is stored and doesn't have to be set after turning ignition off and on,SLE is installed into the radio case, invisible from outside,no change to another radio (DIN-case) needed; the pleasant Rover 75 dashboard optics is left untouchedinstallation procedure takes about 30-45 minutes
