Originally Posted by Meridialien
Malcolm ,

That leaves me in a very difficult place .

I don't live in the UK but have been having problems with my system since adding HD621/AC11/3 X 7200S .

90% of the time , the sound is majestic but the rest of the time the signal to the centre channel seems to be curtailed ( Ive described it to M as ' losing cabin pressure ' whereby the whole thrust of the music or movie just drops off , often leaving only the centre tweeter working on that speaker !).

It happened last night on the intro to ' Casino Royale ' on BD and then rectified itself . It happened this morning on King Crimson's ' Red' on DVD-A and its happening , as I type , on ' Riding with the King ' DVD-A frown

I was in contact with M over the summer as my dealer was on extended leave of absence and did carry out some of the suggested tests they recommended ( eg. swopping out the centre and front left speakers to rule out the centre being the cause ; centre played perfectly for a full day in its new role . Unfortunately , the front left did likewise ! )

Again unfortunately , communication from M ceased suddenly and I'm left with ( temporarily , I hope ) and expensive ' folly ' and no recourse , apparently except to route my enquiries via my dealer . This brings to mind M 's own analogy in the ' DSP Path' pdf recently re-issued :

" Traditional analogue systems behave much like the childhood game in which each player repeats a whispered message into the next player`s ear, and so on down a chain. Each analogue link - turntable, amplifier, cable, speaker - whispers an analogy of what it hears to the next, but something is always lost or added. What emerges at the end, while charming, may not resemble the original message. "

Surely it would make more sense in this case to communicate directly or even ' remote desktopply ' wink to get to the bottom of this as it has been ongoing since February of this year and most of the equipment is still supposed to be under guarantee !

I would never hesitate in recommending M kit on pure sound quality terms when it works but I feel it would be remiss of me not to point out the potential pitfalls of larger , more complex system when you don't live next door to a ' Premium Partner '

Apologies if this is perceived as a rant , but the F80 and most Denon Surround-in-a-Box systems would sound better than mine does today and its quite depressing .

Now back to your normal programming........

~M~

This sounds like a nasty issue to resolve.

Are you running the HD621 direct to 7200's with no Preamp?

If you are running a Preamp. I would try taking the HD621 out of the picture and see how stable things are.

Why do you need an AC11 if you have all 7200s?

I'd try to eliminate AC11 if you can because nobody has reported a problem like this and very few folks have an AC11.

It sounds to me like "who is Master" is getting mixed up. Or "Layout" is bouncing between the two layouts. By any chance do you have both layouts set identical? (that may help workaround the issue if you have them set different). I think this only applies if you have a preamp.

Again though, if you have no preamp you're in new territory and a bit limited in what you can play with to help identify the issue.

Often if you have enough components you can swap, leave out, etc. it's enough to find the culprit.

Try swapping who is master (if it's allowed in your setup, there may be restrictions with your setup and the AC11).

Even if you have to switch to non-RJ45, I would try it, which would help remove the AC11.

Yes, I know you should not have to, but the one loosing out is you and enjoying your investment.

If you can pin point the issue then you'll have better data to communicate with.

Try not running a center if you can. You should be able to do this.

So when you get "tweeter only" sound out center are you sure the other drivers are completely silent or just severly attenuated? If attenuated then it could be a layout/bass management bug. If totally silent, it sure does point to the center speaker. Because nothing outside the speaker could (normally) make midrange and bass driver go completely silent and keep tweeter going. But there are things that could attenuate it (like layout/ bass management issues being irratic).

The HD621 does send flags to trigger layout changes (to the preamp). Often an intro/DVD-menus etc. will be in a different format from the movie and can trigger a layout change.

If I had a preamp and it were my setup. I would try to simplify it as follows. Set ALL 3 speakers large and make sure it's that way in ALL layouts. I bet that would *work aound* the issue if they are set different now. If that works you can proceed one step at a time to sort out what the issue was. This would basically make it so flags for layout changes from HD621 are ignored. And makes bass management pretty basic. This also assumes the mid and bass driver are just attenuated and not silent.

- Fiddler (IMHO)

If you think listening to music is fun, try learning an instrument.
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