FE 166/ 167/ 206/ 207 - 40 watts?

[otto88]

A 40 watt tube amp is underway. I have a big room and when my wife is out like to crank it up and hear it over the house.

Aftyer looking at quite a few options (including for a while three ways):

I want to use one of these four Fostex above a 15" midbass (Lambda, smooth - on axis up to c 2kHz), to cover "only" from a XO point to be trialled, c 500 – 800 Hz and up. ie a 2 way passive with 94 - 95 db sensitivity

Both to be open baffle. The Fostex quite likely EnABLed.

Relieving the bass and lower mid excursions, would all these Fostex handle 40 watts?
Presumably then depending on my distance from the speakers, being capable of c 105 – 107 dB peaks – cleanly?

Fostex spec sheets say the rated watts inputs are:

Rated watts "Music Power"(?)
166 & 167 22 65
206 30 90
207 45 90

Fostex specs are optimistic, however I’d be using them very conservatively.

Sound realistic?

[Inductor]

I'm not into amps and watts (yet) but is all a marketing tool. You have a music output, so is about double max or continuos amp output (generally for a few seconds only). Then reduce for RMS. Say Music Power 100W, then look for the one you want that is Rated Input 31W. If you have this max output is fine for me. You can work with lower RMS also (percentage lower than all the peacks).

[otto88]

I normally never look at ratings - though normally use drivers where the driver rating is 3 – 10 * higher than the amp output.
Here they're close:

So the question is about how much you could increase the rating, when most of the bass and lower mids (< 600 Hz) aren't going through?

[planet10]

Set up like this, driven by a 40 w amp (active?) you should be VERY loud using all of your amp up....

dave

[hilbren]

I'm using a 3.5 Watt single ended tube amp on a Fostex FE166E.
This setup can go very loud!

Almost forgot, this setup is open baffle..

[otto88]

I dont doubt it's VERY loud, up close

But I might be listening 15 m away, as I said it over (or throughout) the house, ie through walls.

So used > 600 Hz, 40 w wouldn't stain the drivers?

[hilbren]

Let me say it like this: a friend of mine lives in the same street. (one house and one street in between) And he said that he could here my music. At that moment I still had some room to tune up the volume... (I did have my window open, this window is not pointing in his direction (90 degrees off))

Is that enough?

[otto88]

in 6 months I will be living in a non urban district.
And I don't intend to do this every day! Maybe 2 - 3 times a year. Maybe once a year. But I want the system to be able to handle all situations

You are questioning how many dB are needed:
That is partly personal, and remember I am referring only to peaks, not averages. And "undistorted"

Some folk (GM) want 120 dB. I used to aim for 105 Db peaks, now I aim for 110, to have a littel in reserve.

But my question is about the effect of restricted LF . .

Cheers

[mrybczyn]

if you're looking for something all over the house, why not build several smaller speakers, and set them up in different rooms? you can stream audio over network to independent players in each room, or run the speaker cable from a central amp...

[lousymusician]

Originally Posted by otto88

I dont doubt it's VERY loud, up close

But I might be listening 15 m away, as I said it over (or throughout) the house, ie through walls.

So used > 600 Hz, 40 w wouldn't stain the drivers?

I have FE166E's passively crossed at 300 Hz to 2-15" Jamo woofers per side, all OB. I don't find the OB bass 'follows' me through the house that well, and the Fostex start to break up if pushed too hard. They may not break, but they don't sound their best cranked up.

To fill the house with sound, I'd think more about using the Lambda in a box with a horn/waveguide tweeter crossed up around 1500. The Fostex/ob system would be nice at lower volumes (i.e. when your wife is home).

JMO, of course.