s.e.x kit and Focal speakers

[walajeremias]

Hello everyone!
I am looking to use a s.e.x kit with my Focal chorus 706 speakers, which have the characteristics below:

Frequency response (+/- 3dB) 55Hz - 28kHz
Low frequency point - 6dB 47Hz
Sensivity (2.83V / 1m) 90dB
Nom. impedance 8 Ohms
Minimum impedance 3,6 Ohms
Recommended amplifier
power
25 - 120W

And also use for low impedance headphones, like audeze or similar.

Will s.e.x kit work?

Thanks!

[Paul Birkeland]

Sound will come out for sure!  If you asked this question 20 years ago, we would likely say absolutely not, but we have since observed a good number of folks using 87-90dB sensitive speakers with SEX amps and Stereomours with no complaints, so you'll be in that gray area where in a small room where you're sitting close to the speakers and not listening loudly, it will likely be OK.  In a larger room, at larger power levels, or with very complex music, maybe not so much.

[walajeremias]

Thanks a lot Paul!
Well it will be like 20-30 m² of room, since these speakers are not suited for something larger than that

Will it still be good?

[Paul Birkeland]

I would say try it and see or at minimum take some measurements of what kind of listening SPL you reach 1M away from your speakers.

[walajeremias]

It is very hard to just try it, because I will import the SEX amp to Brazil
Is there any way to measure the SPL with simple tools? Maybe a smartphone mic?

[Paul Birkeland]

Yes, use your smart phone and a measuring tape to get 1M away from your speakers, then listen at a normal level.  There should be a peak hold setting that will tell you the maximum SPL achieved.

[walajeremias]

Awesome

So I've tested.

Around 80 dB in a normal volume, 1 meter (3 ft) distance

[Paul Birkeland]

You could get there with 2W.

[walajeremias]

hmmm

then it will be the max output of S.E.X?

[Paul Birkeland]

This is a handy calculator:
https://myhometheater.homestead.com/splcalculator.html

You have 90dB sensitive speakers, 2W of amplifier power, 3 feet of distance, 2 speakers, then you can fill in the placement.

[walajeremias]

Yep I think that calculation nails it

Even at further distance (like, 10 feet) would be a reasonable sound volume I guess....

[Paul Joppa]

In most rooms,  the sound level is uniform unless you are closer than about one meter. This is because of room reverberation and is called the critical distance.

In large rooms, such as churches or concert halls, it can be 3m to 10m - but the audience is still in the reverberant field

[walajeremias]

Great! nice to know

Well it would be by my own pleasure in a room/apartment no more than 20 m² (I think). So it would be enough even for loud listenings.

Thank you once more Paul!