Hi,

Obviously physics dictates air movement and bass, but practically speaking, for a similar range of speakers from the same manufacturer, which will have the best sound quality, bass, midrange, etc?

The application would be the rear speakers on a w123 coupe and sedan.

With a clean enough looking grille, Id be OK putting an aftermarket speaker/grill in the cars... At least the CD.

But Im trying to grasp the practical benefit to going bigger, particularly to 6x9...

Id have then fed via an amplifier...

Thanks!

__________________
Current Diesels:
1981 240D (73K)
1982 300CD (169k)
1985 190D (169k)
1991 350SD (113k)
1991 350SD (206k)
1991 300D (228k)
1993 300SD (291k)
1993 300D 2.5T (338k)
1996 Dodge Ram CTD (442k)
1996 Dodge Ram CTD (265k)

Past Diesels:
1983 300D (228K)
1985 300D (233K)

If you are still looking for speaker you need to try sites like eBay.

That doesnt answer the question I asked though...

__________________
Current Diesels:
1981 240D (73K)
1982 300CD (169k)
1985 190D (169k)
1991 350SD (113k)
1991 350SD (206k)
1991 300D (228k)
1993 300SD (291k)
1993 300D 2.5T (338k)
1996 Dodge Ram CTD (442k)
1996 Dodge Ram CTD (265k)

Past Diesels:
1983 300D (228K)
1985 300D (233K)

quality is subjective and difficult to assess, but the larger the diaphragms, the louder and deeper the possible bass. between two round speakers it is trivially easy to say that the the 6.5 will out-rock the 5.25. i would likewise expect a 6x9 to do better than the 6.5. how much better? not that much, probably, but i would always err on the larger side where there is room to accomodate it.