FE126e Bass Reflex Problem

[edward87]

I recently decided to build a pair of speakers using the fe126e driver. Due to limited time and tools i went for the recommended fostex bass reflex design because it looked easy.
I tried to follow the designs as closely as possible and i think the job i did was pretty good . I havent tweaked the speakers or added damping inside or anything, just put them straight in and started playing music
I have them set up with a small 10W amp and for the most part they sound great! Amazing detail, everything sounds really clear and i am noticing things in music i never heard before! The only problem is the bass. Below 60hz i cant really hear anything much (which i expected), then the bass comes in. However it soon drops off again and goes fairly quiet before coming in again at around 150 hz (These frequencies are rough guesses from listening to a 20hz - 20khz sweep). This results in quite a noticeable "one note bass" when listening to certain types of music
I am wondering if there is a way to improve the bass between 60 - 150 hz some way, make the response a bit flatter.

Any suggestions appreciated

Thanks, Edward

 

[Bob Brines]

Welcome to room mode!

If you have an 8' ceiling, you have a peak ~70Hz with serious troughs either side. The suck-out at 150Hz is floor/ceiling bounce. There is really nothing you can do to the speakers to fix the problem. You will have to do some room treatment to minimize the problem.

Bob

 

[chrisb]

Depending on which of the 2 boxes "recommended" by Fostex (either the 10.5 liter simple ported, or the "unique hybrid BR/BLH" ), IMHO you'll can't expect much in the way of decent bass (lets say upper mid-bass down) with this driver, regardless of optimized room treatment, BSC, EQ etc.

To really shine on its own -i.e. without support woofer(s), this driver really wants some type of BLH- of which there are numerous well proven DIY or open source designs.

edit: then there's the matter of "synergy" - what type of 10W amp? I've heard these sound much fuller, warmer and engaging with a DIY 3W P/P or SET tube amp (Bottlehead 2A3) than with 20 watt Class T (Kingrex T20) or even 50W conventional Silicon amp (Rotel RB850)

 

[planet10]

As Chris says, FE126 really needs a horn to make any bass... in a BR a roll-off starting below 150-200 Hz is about right.

dave

 

[djn]

You can also take them outside and see if that hole is there. I think Bob is right. Room suck....sucks

 

[chrisb]

You can also take them outside and see if that hole is there. I think Bob is right. Room suck....sucks

fair enough, but being fairly familiar with this particular driver and the quantity and "quality" of bass performance from the enclosures under discussion, I think there may be 2 separate issues at play