Hi, DJones,

Hope my previous post did not offend. I tried to be clear that I believe you personally do fully understand the dealer's financial constraints.

Next, let my share some of the lessons learned in my 10 years, and dozens of installed pairs, of all Meridian speakers, up to and including DSP8000s (which will also clamp under the following conditions). Some of this has been covered or at least implied, in other posts, but bears repeating:

1. When purchasing a full 24/96 upgrade from my old store, you would certainly have gotten installation and testing at no additional charge. That you didn't is a troubling indicator of dealer service, though it appears they've tried to make up for it. Equally troubling is the recommendation of DSP7ks or the 24/96 upgrade, neither of which should be noticeably pertinent to your problem, in my experience.

22. Calibration (using the G91 -- not available with just the 518 and 500) is not an issue for overheating, as you cannot calibrate digital speakers higher than unity gain, only lower, using any Meridian surround processor. And in a large room, sitting far from the speakers, it is not appropriate to expect or try to get a calibration level of 75dB (this is a common misconception stemming from poor choice of wording in the Meridian processor manual). My own 6000s are in a 23'x28'x11'high room, I sit 12.5 feet from the speakers, and get a calibration level of no more, and often less, than 73 dB at unity gain. I definitely do not use the gain adjustment available in my Z-Systems RDP1 to get higher levels in calibration, but am more than satisfied with the volume levels available.

When using the 518, howver, it is possible to set gain above unity. Don't -- it will definitely cause clipping in the digital domain with high-level software, which can blow tweeters and cause overheating. Make sure you do not apply digital domain gain in the 518 with either the 500 or the G91. Don't use 518 gain to get 75dB calibration levels with the G91, either, for the reason mentioned above.

Please identify what software you are playing. Constant play at 85 (or even 77) of heavy metal or just any loud rock with few or no quiet passages to give the amps a rest will cause overheating,and resultant clamping to protect the speaker (though it shouldn't blow tweeters!). The latest speaker software has added additiional thermal clamping to the midrange driver to help with this problem, and should have been included with the 24/96 upgrade. Latest software is v5.05.

Any of the above can cause permanent damage to the midrange or bass drivers of your speakers. And once that occurs, the only solution is to replace the drivers themselves. Sending the back panel as opposed to the whole speaker to Atlanta won't help.

Finally, do take seriously recommendations to have your hearing tested by a professional audiologist. Most of the so-called tests available on the Web, on CD discs, etc. are virtually useless (e.g., no professional audiologist uses or will guarantee test results above c.9kHz or so). Very high frequency hearing (above 9kHz) is not an issue for your loudness concerns, which are largely a matter of midrange hearing; but any exposure of more than 15 minutes continuous to SPLs above 100 has been established to cause permanent midrange hearing damage in some instances. If this has occurred, the continuing to try to get the levels you love may just result in more hearing loss.

Sorry if this seems redundant to other posts (remember I'm a newbie!) but I thought it might help to gather it together for your consideration.