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      09-14-2012, 05:58 AM   #8
United Kingdom

Drives: BMW X5 xDrive40d
Join Date: Jul 2011
Location: London

iTrader: (2)

Originally Posted by mob17 View Post
Regarding playing it in a street its simple, turn the ms-8 volume down and then use the pink noise to set gains. The pink noise is unfiltered so you have to do it at lowish volumes. Obviously you have to ensure that you dont give a speaker too much power. The point of level matching the speakers is that it gives the ms-8 ideal conditions to calibrate and process all that info. You can increase the gains after but obviously this would cause the ms-8 powered channels to be attenuated. So it wouldnt be a good idea if you have a ms-8 powered centre.

I think the best course of action would be:

1) find out at what gain position is the maximum safe gain for each speaker. Either do this by ear or multimeter.
--> Why is this required? As I wrote before most of amp will anyway easily overpower ms-8 amplification

2) level match. So probably means reduce your amp gains to match rears and any other ms-8 powered channels. I think even if you dont reduce the gains, the ms-8 will limit the power of your amped speakers anyway.
--> If this is the case then isn't level matching pointless as MS-8 will anyway reduce the input to the amp automatically matching the level across the car?
3) increase gains to level desired.

In my set up this worked because the only ms-8 powered channels are my rears. So after calibration i can increase my amp gains, with only my rears being attenuated, which i dont really care about. However if you have an unamped centre (which i think you do?) then it would really mess with your front stage if you increased the gains after calibration. So you have 3 options:

--> Yes I have unamped center, no one does 5 or 7 mid-range to high channel amp . Neither I can fit 3 boxes (1 MS-8 and 2 amps) in my E60 However I have exactly the same driver across the car, Stock L7 speakers (and alpine tweeter attached to the centre), they are 2 ohm and think should draw more power from ms-8 then DLS 4 ohm ones. But no way they can match PDX-4.150 150watt channel each, I know 150 watt is a bit of overkill but I didn't have a choice.

1) Level match and leave the gains as they are. This is the best solution if you don't want to add anything else.

2) Get a very efficient centre speaker, like a DLS 424, so its "louder" for a given wattage. So it might even match your amped channels but still running off the ms-8. Even if it doesn't match exactly, it will be louder than what you have, therby reducing the amount you turn your amp gains by.

3) Amp your centre. Might be able to amp your rears for similar prices.

For calibration volume its the same way as i pm'd you. Basically level match with the pink noise in test menu, then using an iphone app adjust the ms-8 volume until you get a 50-55db reading. This will give you a range of 5 ms-8 volumes which you should try.
I am assuming all these needs to be done from driver seat, even the level matching using iphone app, correct? or shall I do it from centre of car which means SPL from all the speaker will same (around centre console)?

Also advise me if Focal KRS/VRS 100 range will help me here (can't afford Morels) to get better result (not that I am complaining with the current setup, it is good, looking for step further), I can source them for around 180ish delivered, worth the money in my setup?

Sorry again for basic questions but I am trying to understand and learn the idea and procedure of level matching not just to follow it for the sake for getting it done.
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