Basic gramophone question…

I thought this might be useful as a real world illustration in an E89

What we have are Eton B100 X N 100mm speakers designed for BMWs..they retail for around £200 a pair


https://eton-audio.com/upgrade-audio/ug-b100-x-n.html

What we have is 3 screen shots from the DSP s/w tool managing the DSP/ amp in my car.

One shot shows what, in an ideal world we would expect the speaker to perform like..that is a flat line across its entire useable response range.

In my car there’s one in the dash behind the idrive screen and one centred between the seats at shoulder height.

Once we run the real time analyser which during this process is listening to ‘pink noise’ that is random noise adjusted by frequency for constant energy and then work out the response , the DSP s/w then works out what corrections to apply across the whole applicable spectrum to make this speaker sound ‘normal’ adjusted for the industry standard car..(living rooms have a different correction profile).

Before we run the RTA we adjust the calculation to take into account where each speaker is in relation to the listener..so we input the straight line distance between each speaker and the listener into the DSP s/w tool.

There are two pictures, the one with most squiggles is the front speaker, the other is the rear speaker.

Several points arise..

The same speaker in a different location behaves differently based on what lies behind the speaker, but more importantly what lies ahead of the speaker…

Clearly in this case the front centre speaker is having all sorts of issues as the sounds st different frequencies bounce of the dash the windscreen etc.

This same technique is used now in almost all car audio since around 2010..it’s a way of compensating for cheapo speakers and the challenges of each car cabin..of course normslly the manufacturer locks these adjustments into the audio system and are not user useable.
 

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Firstly thanks for the links to the available kits B21 and Silverstar. :thumbsup:

Having listened to a 3 series Source sounds in Sheffield built a couple of years ago comprising of Focal mids, tweets and two underseat subs driven by the standard head unit but through a DSP and set up with an anyliszer that’s what I’m aiming for, wasn’t cheap, nor was it crazy, but the sound was the best I’ve heard by a long way for the cost. I can’t get anything under the seats as Silverstar said so it’s either a sub in a custom build behind the passenger seat or in the boot, not decided yet. I’ll fit everything then get Source to equalise it. What’s spoiled it is the kits mentioned would have sufficed but after hearing the 3 series…. :o :oops:

If you put a decent kit in a roadster yes some of it is lost but there’s more than enough to still make it superb, Porsche do a £3200 Burmester option that is very very good, doesn’t need anything adding, sounds pretty epic in a Boxster roof down, so for me anyway it’s worth it. :driving:
 
IMHO having seen what a few folks have done retrofitting the 676/677 sub trim on the back of the cabin and the quality of the bass that would be an easier option..quite a few second hand panels available on the market..

I’m pleased with this set up now with better subs and the DSP/amp..
 
john-e89 said:
Firstly thanks for the links to the available kits B21 and Silverstar. :thumbsup:

Having listened to a 3 series Source sounds in Sheffield built a couple of years ago comprising of Focal mids, tweets and two underseat subs driven by the standard head unit but through a DSP and set up with an anyliszer that’s what I’m aiming for, wasn’t cheap, nor was it crazy, but the sound was the best I’ve heard by a long way for the cost. I can’t get anything under the seats as Silverstar said so it’s either a sub in a custom build behind the passenger seat or in the boot, not decided yet. I’ll fit everything then get Source to equalise it. What’s spoiled it is the kits mentioned would have sufficed but after hearing the 3 series…. :o :oops:

If you put a decent kit in a roadster yes some of it is lost but there’s more than enough to still make it superb, Porsche do a £3200 Burmester option that is very very good, doesn’t need anything adding, sounds pretty epic in a Boxster roof down, so for me anyway it’s worth it. :driving:

For the subs I think you have three or four options,

1) as done by Mr Tourette (I think) install the underseat subs but behind the seats attached to the lower part of the bulkhead trim

2) Retrofit subs in the location where the factory subs are installed as per what I did, great results but a huge undertaking

3) Build a custom box with appropriate subs to sit in the area behind the seats where the small shelf and netting is but again that's a lot of work and if you have pass through in the bulkhead you will loose it and

4) the final option and probably the easiest with good results is to get a downfiring enclosure to sit on the boot floor, Kicker do one with a 10" sub (I think) that fits perfectly in that space only caveat is you need the pass through in the bulkhead.
 
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