How to conjure dynamics from FR drivers?

[steviedon]

Disclaimer: Yes, I have searched....extensively. Dynamics......complex low low bass lines, kick drums, guitar shredding, etc.

Due to my recent acquisition of some fe127e drivers I'm planning a side project as a housewarming gift for a friend......the preliminary plan is the fonken floorstander mkII, w/ a sub (w8-740p) playing down to 30ish hz. This friend happens to LOVE hard complex rock/metal (pantera, mudvayne, RATM, etc. etc.).

From my scouring this forum and others, it seems a satisfying listening experience (within the hard rock genre) can? be achieved by relieving the FR driver mains of <100hz input. I can do this easily in the digital realm as I'll also be gifting him my old SS reveiver.

The Q is......am I urinating up a rope here, or am I on the right track? Myself? I love the fullrange sound, but for a rock junkie who also sings lead in a hard rock band, will this plan be ultimately disappointing?

Critique invited. I can post my sims of the sub if needed. Thanks in advance for any input.

[ra7]

Giving the FR driver help below 100 Hz allows you to play louder. And it will certainly play rock, but if you're expecting concert levels then it simply isn't going to happen.

[Josephjcole]

I've got a fostex 108 which plays 300Hz up with a 12" prosound driver from there down. That certainly helps with the dynamics... it's still no match for a compression driver though. Have you seen the various econowave threads? If I was building something for someone who really wanted to rock I would start with something more along those lines. Or possibly a Emenince Beta 12lta.


Joe

[Nelson Pass]

Maybe you should make some headphones out of them.

[ra7]

Originally Posted by Nelson Pass

Maybe you should make some headphones out of them.

[Godzilla]

>>> This friend happens to LOVE hard complex rock/metal...
>>> a sub (w8-740p)...
>>> Maybe you should make some headphones out of them.

Lol, Nelson! I have 127e and that beefy TB sub too. It's not very efficient and will require power to goose it right. I'm curious what cabinet you're using with it?

My 127e's are hooked up to Onkyo solid state and the whole setup remains off for months at a time. They got much more play time when the cheap Sonic Impact amp was in place and more still with the Cary tube amp... but i aint no metal head (not that there's anything wrong with that).

[pjanda1]

Does your old receiver have links between the preamp and amp? If so, I suggest driving the sub(s) from the preamp, and using at least a single cap as a high pass filter for the mains. You need to know the input impedance of the amp section to get the value(s) right.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers

[Vix]

You can still use that tiny Fostex, you just need a pair of Goldwood GW-1858 and some wood: http://www.quarter-wave.com/Project08/Jordan.pdf

That will rock!

[mondogenerator]

i like a bit or Pantera myself, and one thing ill say is:

go with the sub, XO the fostex somewhere suitable.

but imho the most important thing:

i dont know the frequency response of the driver in question but with any guitar music, due to the use of presence controls on amplifiers, certain fullrangers may sound 'harsh' IF there is any significant peaks in output around 3-4k. Other than that theres no reason it couldnt sound great. i kinda agree that maybe a big mid-HF horn might do a better job with a 12" or bigger woofer, if only in the polar response higher up in frequency. but then with the fostex, you could go OB and for the sub: H frame or even just 'normal' vented, sealed etc

[chrisb]

Originally Posted by mondogenerator

i like a bit or Pantera myself, and one thing ill say is:

go with the sub, XO the fostex somewhere suitable.

but imho the most important thing:

i dont know the frequency response of the driver in question but with any guitar music, due to the use of presence controls on amplifiers, certain fullrangers may sound 'harsh' IF there is any significant peaks in output around 3-4k. Other than that theres no reason it couldnt sound great. i kinda agree that maybe a big mid-HF horn might do a better job with a 12" or bigger woofer, if only in the polar response higher up in frequency. but then with the fostex, you could go OB and for the sub: H frame or even just 'normal' vented, sealed etc

I'm quite familiar with this driver and the particular enclosure steviedon has in mind, and while the FE127 is (was) not the "harshest" of the 12X series, it does have some issues a little higher ( circa 6-7k), particularly when driven hard, that can be substantially reduced by certain treatments.

Several other models in the FE/FF series have been used in OBs, (notably FF85K and FE126E), but the floor space required for them to work best (even an H frame) is not always available - which the selection of FS Fonken design suggests.

In a smallish room a single powered woofer XO between 100-120 would be a neighborhood in which the 127 could still do well in lower midrange dynamics up to moderately high levels. This is within the range of line level low pass filters on most compact pre-fab subs (or you could build your own). Keep in mind that to gain full benefit, you'd want to HP the Fostex, and the passive speaker level networks on cheaper plate amps is not their strong point, and not all are easily accessible for modification/ parts upgrade.

And of course, the end user might not be as discriminating as the builder, and non-destructive distortion or harshness might be quite acceptable.