Teansfer function 250hz roll-off followed by peaks, dips and peaks and dips look terrible to me.
Perhaps a front horn to bring up the low treble - upper mid combined with a BLH to help with the bass would even things out more, IDK. Looks like a lot of work.
I don't recall the limited ed FESOL series this is based on as having such a ragged Fq resp. transfer function.
What am I missing here, are you seeing something I'm not?
Perhaps a front horn to bring up the low treble - upper mid combined with a BLH to help with the bass would even things out more, IDK. Looks like a lot of work.
I don't recall the limited ed FESOL series this is based on as having such a ragged Fq resp. transfer function.
What am I missing here, are you seeing something I'm not?
Its a typical fr response for typical full range. Except not altered to make it look better.
See Rutcho's measurements for similar fullfange, yes, they look ugly, but such is reality of fullrange.
Loudspeaker Raw Driver Measurements
See Rutcho's measurements for similar fullfange, yes, they look ugly, but such is reality of fullrange.
Loudspeaker Raw Driver Measurements
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So, what do you guys make of the Fostex FE208NS 8"? Any good? What size and type of box, horn or OB?
Fostex FE208NS 8" Full Range
Fostex FE208NS 8" Full Range
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Almost all modern foam surrounds are very stable and do disintegrate like the 1st generation.
Old speakers with foam surrounds… first thing you do is gently poke them too see if them fall apart.
Cloth is old school. 1st gen FE103 (up until 2yk) have cloth surrounds. Othen coated which sometimes causes proplems (stiff surround syndrome). With modern forming techniks we may well see something like formed flax surrounds.
Volvo/Polestar standard seats and other interior bits are made from flax. There are initial reports of work with a flax based alternative to carbon fibre, 40% heavier ATM, but much more recyclable and once sorted probably cheaper. I can see a lot more applications using what they are learning. Like hemp (could also likely be used the same way) a million uses.
Progress in materials technology and every other technical disipline are improving/extending/innovating at an ever more rapid rate. Just think, the modern telephone (ie pocket computer) is only about a dozen years old.
Almost all speaker driver makers are VERY conservative and slow to embrace new stuff. Even so a 20 year old gem like the FE108e∑ is still a competitive driver. FExxx in general have some significant issues, the really nice ones are few & far between. They ar enot without their assets, and many people love theirs. Most FExxx are also expecting to be driven with a higher output impedance amplifier. Fostex has made more than a few that were dogs (ie FE138e-SR). On paper this one makes me think it might be one of those.
dave
Old speakers with foam surrounds… first thing you do is gently poke them too see if them fall apart.
Cloth is old school. 1st gen FE103 (up until 2yk) have cloth surrounds. Othen coated which sometimes causes proplems (stiff surround syndrome). With modern forming techniks we may well see something like formed flax surrounds.
Volvo/Polestar standard seats and other interior bits are made from flax. There are initial reports of work with a flax based alternative to carbon fibre, 40% heavier ATM, but much more recyclable and once sorted probably cheaper. I can see a lot more applications using what they are learning. Like hemp (could also likely be used the same way) a million uses.
Progress in materials technology and every other technical disipline are improving/extending/innovating at an ever more rapid rate. Just think, the modern telephone (ie pocket computer) is only about a dozen years old.
Almost all speaker driver makers are VERY conservative and slow to embrace new stuff. Even so a 20 year old gem like the FE108e∑ is still a competitive driver. FExxx in general have some significant issues, the really nice ones are few & far between. They ar enot without their assets, and many people love theirs. Most FExxx are also expecting to be driven with a higher output impedance amplifier. Fostex has made more than a few that were dogs (ie FE138e-SR). On paper this one makes me think it might be one of those.
dave
Good to know. 108e∑ is also 90dB vs. 108NS 87dB. I guess there's a reason the current e∑ line has remained unchanged for so long!
I can confirm that the FE108NS does indeed sound excellent. I commend Fostex for publishing truthful response graphs.
There is indeed a -5dB dip at 750Hz. But it doesn’t seem that bad once mounted in an enclosure. The overall sound character is similar to the FE108EZ but will a little more attack on the leading edge of transients. Overall a beautiful sounding driver. Shown is the response in a 3 litre sealed enclosure measuring 190mm wide.
There is indeed a -5dB dip at 750Hz. But it doesn’t seem that bad once mounted in an enclosure. The overall sound character is similar to the FE108EZ but will a little more attack on the leading edge of transients. Overall a beautiful sounding driver. Shown is the response in a 3 litre sealed enclosure measuring 190mm wide.
Fostex’s most recent published data is no better or worse than actual test data from other brands with similar full range drivers. It’s simply that Fostex no longer publishes frequency response graphs with 1/3 octave smoothing. You can see this in my most recent blog post where I compare the FE108NS against the long standing FE108EZ. The new NS version actually measures smoother than the EZ series. Off-axis polar maps are also improved with the new version.
https://josephcrowe.com/blogs/news/fostex-fe108ez-versus-fe108ns
https://josephcrowe.com/blogs/news/fostex-fe108ez-versus-fe108ns
