Quantifying Performance Trade-offs from non-"textbook" BR Alignments

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Measurement, in-room response if suitable to your tastes.
Glaring result would be presence of boominess indicating a rise in the q of the lower knee.
Muddy sounding(not taut) drums due to a stretching of group delay transients.
 
Last edited:
True.
Delay around tuning, different tuning has a different sound.

To me 40-50hz is thuddy or thunky, some call it one note bass and i see (hear) why.

27hz-30hz sounds better to my ears.

At twice above tuning, the delay is same as a sealed.

But..........

Stuffing ports going from 27hz tuning to sealed (approximately 1/2 area needed for 4th order), it wasn't any "faster", it just seemed like someone went to a 10 band eq and slid the 30hz slider down 6db, very unsatisfying.

Ebs (extended bass shelf where you tune well below the f3) tuning can seem like a clean but lean sealed.
I also have a sub that is tuned to 27hz, also its f9 (9db down).

It is very clean but needs some boost for earthquake rumbles.


I have a 10" b102 in 1.4ft3 tuned to 47hz, it runs wide open and rolls off above 1khz to a tweet.
Ideally it would be in 2.3ft3 tuned to the same but need slightly larger box.
Its qts is around .4 and fs just under 50hz.
I keep the port stuffed, but am curious what it would sound like tuned to 27hz.........
 
Last edited:
Some says, it's irrelevant to use "old school" textbook alignments. Just use an adequate simulation software and see the result as graphs. It's all ok, but how to interpret the results is another question.
Otherwise, the classic T/S parameter calculations works only around the actual drivers FS, this is why I find it difficult to predict what will eventually be the sound of the box. You usually don't use drivers around FS only.
Scan-Speak's Toolbox software uses advanced driver parameters which is closer to the real world nature of a speaker. Unfortunately only a few Scan-Speak driver has the advanced parameters published, but i found it to be reliable and the predicted response is much closer to what i measure in the built box, than with classic parameters.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.