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Hey, stop that scrolling, the answers are down here... no peeking... you've got to take the tests like everyone else.
Shop drawings demonstrate to the consultant that the contractor has considered the details and implications of what they are about to build and install. They also allow the contractor, the consultant and the architect or owner to verify that everyone is expecting the same thing when the job is done. While some contractors seem to dislike shop drawings because of the time it takes to finish them, but a well thought out set of shop drawings can be like a paint-by-numbers set of instructions for the installation crew.
We really expect that by the time we've been asked to make the substantial completion inspection that the system should work properly, and all the equipment should be properly installed. The last thing we want to find is that the substantial completion inspection was scheduled so that the contractor could meet the net 30 deadline on the supplier invoices. If the inspection was already scheduled, then inform the consultant as soon as you know the inspection can't be completed.
Everything had better work, just like it's supposed to. this is not the time to spring any "improvements" on the consultant. All functions and signal paths should function properly.
Aircraft cable is the best choice, as properly installed cable, saddles and crimps or clamps can be quickly checked for integrity. Chain slings have to be removed and x-rayed annually to verify that no stress fractures are developing. Chain rattles, and chain cannot be finely adjusted (pretty much a link at a time). Mountain climbing rope... well, if you have to ask...
There's nothing quite as conspicuous as misaligned connector edges when they are mounted on a square or rectangualr panel. The tolerance we expect to see is about 1 degree off parallel as a maximum.
I hope we don't really have to explain this one. The exposed drain wire in shielded cable should be less than 0.5" long. Any longer and it is prone to making contact with the signal wires when the wire bundle is moved.
Small misalignments generate destructive interference which produces lobes in the coverage pattern. Where the waves from each speaker are in phase, they add together, where they are out of phase they cancel out completely. In between, there is varying amounts of cancellation in the combined sound waves. The cancellation is wavelength dependent, so it changes pattern with each and every frequency.
If there is a microphone that is prone to feedback, then it is the microphone to use to measure the loudspeaker system. It will tell you about the time and frequency domain behaviour of the system as "heard" by the problem microphone. You can find peaks caused by lobes in the loudspeaker system coverage, or other frequency response anomalies or reflections that are triggering the feedback.
If every stage of the sound system signal chain clips at the same time, then the system has the best gain structure for headroom. This may not always be achievable without adding T or H pads in the signal chain. There are situations where the system will be too loud in this configuration, and then the amplifiers may need to have input pads installed. This may result in a loss of headroom in the signal chain before the amplifiers, but an improvement in signal to noise at normal operating levels. This headroom loss can be fudged with a really good quality limiter with lots of headroom, set to allow transients through but catching high average levels.
The correct answer is of course B, make sure all signal paths have full specified bandwidth and that the distortion and noise figures are within specification. This applies to both active and passive signal paths.
Once you have determined the actual signal delay requirement through measurement you should add 15-20 milliseconds to the delayed signal. This has the major benefit of reducing the dramatic comb filtering that may be experienced by moving one's head slightly when in the field of coverage of the main system and the delay system. It also means that the delay setting is suitable for most of the seats in the delay infill area, as opposed to the one seat that the measurement was taken in. Adding extra time also allows the level to be slightly higher without drawing attention to the delayed signal.
When equalizing a system using a conventional 1/3 octave cut and boost equalizer it is preferable to have less than 6dB of level setting difference between adjacent filters. This reduces coloration caused by the filter set itself, and improves the time domain behaviour of the equalizer. If adjacent filters have more than 6dB of difference it is likely indicative of some other problem, possibly a time delay related problem.
Video coaxial cable should not be bent at a hard right angle, it can crush the foam insulator for the inner conductor and make the bend behave like a filter or attenuator. The minimum bend radius for RG58 type cable should be 2.0".
A 1/3 octave real time analyser and a pink noise source is only really suitable for setting the overall system level. A real time analyser cannot be used to set delays as the 1/3 octave wide filters will not show up the narrow comb filters caused by signal delays. An RTA does not have the time domain discrimination to be used to set the direct sound equalization as it integrates all the sound in the room over a 300millisecond time period. Setting the direct sound equalization requires a time domain analyser such as aTEF or MLSSA type analyser.
Oh please, we should not have to tell you, let us know as soon as you know the product is not available, let's not have any surprises at substantial completion thank you very much!
Of all the light output measurements used in video projectors, ANSI lumens is the one with the measurement methodology specified. That does not mean that each manufacturer is absolutely accurate in how they specify ANSI lumens, but it is the only comparable specification of the three shown..
This seems like it should be easy, but oddly enough this seems to be the hardest to get would-be contractors to understand. We don't just pick the coverage, bandwidth, power handling and configuration out of a hat, we've selected the speaker for it's applicability to the application. The coverage, bandwidth, power handling, size, shape and price are all factored into the selection. If you're going to offer an alternate product we want to see some demonstration that you have at least thought about how the speaker has to work in that location. At least we expect the same coverage angle, that would indicate that you know how the speaker will be covering the seats. The old rock n' roll approach of throwing a box up any place, regardless of coverage won't cut it here buddy!
This is the contracting business we're talking about after all. Use the least expensive product in the allowable alternates, it will increase your chances of winning the bid, and it requires less capital outlay at the beginning of the job. This is a business issue not a technical issue, but you have to stay in business long enough to get the job finished.
This is a litagious society we live in, the specification covers everything mounted to the building, even the equipment supplied by manufacturers has to be anchored to the building structure, and those mounting points have to be approved.
Take a factory training course if you want to bid. Until you're familiar with the product you can't formulate a realistic bid for labour. If this is the first project using the product, we don't want our client being the guinea pig for your learning curve. there's nothing worse than having a partially finished project hung up for weeks or months because the software has caused a problem.