I have noticed a number of people are running Beyma TPL's " open baffle" and with custom rear chambers. I have therefore experimented to see what the effects are of removing the rear compression chamber off my Beyma TPL's.
Bit of background - i am running mine in a custom "le cleach" expansion horn which are significantly larger than the standard OEM horns. The only noticeable effect was smoother roll off below <1000Hz. I am currently running them crossed @ 1200Hz and am looking at lifting this as they can sound harse. (I suppose secretly i was hoping the rear chamber experiment may sort out the harshness)
Attached below is a trace of the 3 configurations - all measurements taken from listening position 2.5m away. http://i1227.photobucket.com/albums/ee439/vinylnvalves/beymarearchamber_zpsd6bc79ca.png
The rear chamber i made had non-parallel sides in a 3:2:4 ratio with approx volume of 5 ltrs. I stuffed around 50% of this with BAF.
You can see the OEM chamber has the flattest response, i don't understand why my oversize chamber is so bad. Do i need to put back the felt on the back of the driver? Any suggestions on ways to improve the FR. I think they sound better without the chamber, but the loss of imagery outways this, so some type of chamber needs to go back on them
Bit of background - i am running mine in a custom "le cleach" expansion horn which are significantly larger than the standard OEM horns. The only noticeable effect was smoother roll off below <1000Hz. I am currently running them crossed @ 1200Hz and am looking at lifting this as they can sound harse. (I suppose secretly i was hoping the rear chamber experiment may sort out the harshness)
Attached below is a trace of the 3 configurations - all measurements taken from listening position 2.5m away. http://i1227.photobucket.com/albums/ee439/vinylnvalves/beymarearchamber_zpsd6bc79ca.png
The rear chamber i made had non-parallel sides in a 3:2:4 ratio with approx volume of 5 ltrs. I stuffed around 50% of this with BAF.
You can see the OEM chamber has the flattest response, i don't understand why my oversize chamber is so bad. Do i need to put back the felt on the back of the driver? Any suggestions on ways to improve the FR. I think they sound better without the chamber, but the loss of imagery outways this, so some type of chamber needs to go back on them
Very interesting, pictures of the horn? And some data on size, cut-off frequency etc?
(Please 😃)
Br
Gisle
(Please 😃)
Br
Gisle
- Status
- Not open for further replies.