Hello all:
I have been an ardent reader of all things BeoWorld for the last 2 years and finally have found myself in need of some of the professional advice beyond that which is archived.
Before I begin, I'd like to thank all of the committed contributors to this forum as it provides we Bang & Olufsen owners a ready source of brilliant analysis as well as enjoyable commentary.
That said, up until this week, my system has consisted of a BeoSound 2300 and a pair of BeoLab 6000's. While I have wholeheartedly enjoyed my "dream" system for a number of years, I have been itching to upgrade the speakers to either BeoLab 8000's or BeoLab 3's.
Just this past week, I purchased a mint, like new pair of BeoLab 3's that are approximately 3 years old. I have hooked them to my BeoSound with the appropriate Mk III speaker cables. I confirmed that the cables are Mark III's by both the arrow on the connector end as well as having tested them with my ohm meter. This morning, I had an opportunity to test them at higher volumes as I was the only one home.
First of all, I noted that the BeoLab 3's sound great and am very pleased with the improvement over my 6000's. However, had I not "moved up" and had an opportunity for a side by side comparison, I probably would have continued to just love my BL 6000's and accept them as the perfect speaker for me. Where upon I turn up the volume on my 6000's and experience distortion, I noted that the BL 3's keep things in very good musical order. Base is far improved as well as the overall musical separation. A very nice investment and upgrade! I thought....
It turns out, that I have a problem and this is where I need some advice from the sages of BeoWorld. I loaded up some CD's to provide a good crisp signal source for testing their potential. The 6000's were disconnected and the 3's were hooked up. As I increased the volume, the two Beolab 3 speakers would start to shut off just momentarily and come back on automatically. Sometimes one would shut out and sometimes 2 at the same time. Music would play fine for a few seconds and then shut down. On and off - on and off. What I found most interesting is that the LED did not shift from Green to Orange indicating a trip of the Thermal Protection System. And, again, they came back on by themselves after seconds. This began at about the 72 volume level (the BeoSound 2300 has a 1 to 90 volume range.)
The speakers are sitting on the rubber doughnut stands. I checked all of my connections, both BeoLink and mains to make sure that they were firm. I moved the speakers to different positions and I also switched from "Wall" to "Free Standing" and back. Nothing seems to remedy the situation. Interestingly, it would happen less with a radio station playing as opposed to CD. At one point, the right speaker did trip the Thermal Protection Circuit and the LED turned Orange indicating it had kicked in (or out). As stated in the user manual, I pulled the mains and waited 5 minutes. The speaker recovered. My listening room measures 13 by 24 feet.
For the record, I have never experienced with my BeoLab 6000's a similar trip or shutdown, irregardless of the volume. I also feel that a level of 72 on the volume is far to low to be presenting a challenge to a 250 Watt Ice Amp'd speaker of the $4,200 price range. Is this to be expected due to their small size? Is this normal? If so, then they are certainly not the speakers for me!
I read through the Service Manual and was wondering if perhaps the Power Supply jumpers are in the wrong position - perhaps set for European 220 volt (I'm in the USA). I purchased them from a USA seller and he didn't mention anything negative about them and they look new and appear to have never been serviced or opened and again, it is happening to both speakers. Any advice you can provide would be greatly appreciated!