I had mine setup the same way (CEC TV - Yamaha Receiver via D-SUB). I don't have it hooked up that way at the moment because I bought a pre-amp... but I'll be returning it and going back to my original setup (that's a whole other story). 

If you can live with it for the time being, once I reconnect everything back the way it was (probably next week or so), I can tell you at what volume db my speakers turn on. I know our receivers aren't the same, but it should give you a gauge as to whether your unit is requiring a higher signal to trigger on.

Of course, no problem! I hope you get your situation sorted too, it doesn't sound as plug-and-play as I was hoping!

I had a bit of a play, and the Beolab will turn on while emitting a test tone on the subwoofer. Which leads me to believer the whole system won't turn on until there is some low frequency noise / noise specifically from the sub pre-out. 

Im actually considering getting a powered sub with a 'permanantly on' feature as this does seem to be a common problem with subs with an 'auto on' feature. I clearly have my volume too low ;) 

I mainly bought this system for the beautiful satellites / stands, and as I got such a great deal, I don't feel too cheated replacing the Beolab sub. Maybe when I move in the future, I'll be able to have louder volumes and get the benefit of using this sub again. 

The specs of the Beolab 14 state a crossover frequency of 120hz, so the satellites should be simple to connect directly to my receiver. My only concern is that when powered by the sub, the sats are powered via 140 watts, wheras my receiver only outputs 95 watts (at 8ohms) per channel. Do you think these speakers would need more power, and I would be damaging them in this way?

I would not advice you to do this.

The satelites were made to work with the sub.

There is a Adaptive Bass Linearisation (ABL) built in to the complete setup (based in the sub), that balances the sound of the satelites and the sub at different volume/sound pressure..

I am not sure, that you can mimic this bas management with an ordinary receiver.

You might (?) damage the satelites.

MM

I 100% agree with MM on that last post. However,... I am interested to see what outcome you would get by connecting the satellites directly to an external amp.

Anyway, as promised...

With test tone on left speaker, the green light on my BL14 cam on when receiver read 57.5db.

My SPL read 61.5 - 62.0 db, pointed directly at the satellite at about 0.5in away.

I think that's as accurate as I can get, as to how much signal it takes for my system to turn on. Oh yeah, just to confirm, it's connected to an external amp via the D-SUB cable in AMP mode.

Thanks Earle, i'll check my system tonight to compare.

I'm aware that it's not the most optimal way to connect the components, but at the moment, it's not very optimal to have to increase the volume really loud and then quickly turn it down again before the neighbours complain. I'm just a little confused and frustrated by this bizarre limitation, as I expect to turn my TV on and hear sound straight away.

No problem. 

Be aware, the speakers won't turn on instantaneously, per say. However, you really shouldn't be turning the volume way up before they power up, only to have to immediately turn it back down. 

In my opinion, the system should turn on once you reach the level of normal male speech. The key might just be turning the volume up a bit more slowly. There is a delay before the system detects the signal and turns on... and because of this, if I were to turn up the volume rapidly, I could reach incredible levels before the system actually turns on.

Hope that makes sense. Let us know how it works out!

I have a Beoplay s8 2.1 for around 4 years, and recently I upgraded it to 4.1 and connected to the connection hub via a PowerLink Splitter and three RJ45 PL cables, it sounds better than 2.1 (you could say I am biased ^__^).

And I will further add one more satellite to make a 5.1, then connect the system via a D-SUB cable to the AV receiver, maybe one recommended at this forum.

One way to check whether the s8 is the 1st gen or 2nd gen I learned is, to see the 4-digital Type No. on the top nameplate of the Subwoofer, if the number is ranging from 6237 to 6239, then it’s 1st gen; if the number ranges from 6247 to 6249, then 2nd gen, or MK II.

I really enjoy the 4.1 (2X stereo) now, but I look forward to hearing the real 5.1 from this system.

Lastly, thanks for all the great information here, truly helpful when I made decisions for upgrading the system.