Originally Posted by javeryh
OK - today was supposed to be the day... I cannot for the life of me figure out the equipment. I have no experience with this stuff and it is frustrating me.
- I had a picture coming from the projector but now there's nothing. A green light is flashing which indicates that it is "waiting for a signal" but my PS4 is on and I can hear the sound from the menu. I had a game working but when I switched to a blu-ray I lost the picture and cannot seem to get it back. I can't even seem to turn off the projector.
- When I did have a picture, I was having a hard time getting it to fill the screen area completely. I have been playing with the levelers on the feet but no luck. When I raise one side the other side gets messed up. Probably need more patience. Also, everything seems to be in 16x9 mode - not sure if I'll have to recalibrate for 2.40:1 but I haven't even been able to get into that mode yet.
- My eyes must also be terrible because I can't even tell if the picture is in focus. The green grid that is there for calibration always looks fuzzy no matter what I do.
- When the game on the PS4 was running the picture seemed way too dark. I'm sure there are brightness settings but I haven't found them yet.
- There is a ridiculous loud humming noise coming from the subwoofers. It is so distracting. I am not sure what "gain" is (although I know it's not volume). During the receiver calibration, it asked that I set the volume if the subwoofers to 50% but there's no volume control on my subs so I didn't do anything. The receiver couldn't hear them so I turned the gain knobs about 1/3 of the way up which caused the humming noise.... but now the receiver could hear them.
It feels like I'm in way over my head and I've only got about 4 hours until showtime. Ugh.
First let me say your theater looks amazing!
I’m just about to start construction on my own at home which I’m hoping will look as good as your when it is done.
I see / hear your frustration with the picture and sound setup. I can imagine how weird it must feel.. regarding the humming noise from the subs, it sound like you may have a grounding issue.. check that your sub amplifier is earthed properly and that the internal wiring of the subs is correct. You may also want to borrow a sub from someone else to ensure it’s not a general electrical earthing issue.
Regarding the overall sound system.. it looks like you built the speakers yourself so right now you have no reference for what each speaker should sound like, much less how they should work together as a complete atmos surround setup. It would probably feel weird for anyone standing in your room listening to it because of this added complexity regarding speaker construction. In addition to this you have amps and receivers you’ve not coupled with the speakers before so there’s another layer of complexity.. basically for every piece of equipment you add to a sound system the more layers of complexity there are.
The first thing I recommend you do regarding sound is calibrate your system.
Below is some information regarding calibrating a theater system. I copied some of this from one of my Dolby manuals that we use at work. Even though this talks about 5.1 (or a 6 channel system) for the most part you can duplicate the surround channel calibration for atmos channels as well.
You will need a reference for this. The best reference is Pink Noise. Pink Noise sounds like White Noise but is not exactly the same. You can find pink noise generators on some DVD content, THX discs used to have it in the setup menu for instance. If you cannot find any which specifically say “Pink Noise” then you can always use an App like Tone Generator Pro and generate the noise from you iPhone or iPad using the headphone output.
Listening Room Calibration
Setting up your listening environment is a crucial element in enabling you to properly evaluate content. You should only need to do this once for each monitor system or room; however, quick checks are advised before each session to confirm the correct calibration settings.
Prior to listening in a multichannel environment, the monitoring system must be calibrated to establish a balance between all channels and to ensure that all speakers play back at the correct level relative to the listening reference position.
The best option is to use your amplifier gain (trim) controls to set proper playback levels. Your amplifier (or receiver) should have the ability to adjust the relative level between speakers.
This allows you to maintain optimum signal-to-noise performance from the decoder and BluRay.
To properly calibrate speaker levels, use an SPL meter. A suitable and relatively inexpensive meter is available from Radio Shack. You can also use an iphone App that I often use at work when an SPL meter is not available; the App is called SPL meter.
Relative level between channels is more important than absolute level, so the accuracy of this meter is sufficient for channel balancing.
What is most important is that all of the main channels are set to the same SPL (Sound Pressure Level) absolute level is secondary to this. However, as a guide, here are some examples of conventional level settings.
For film content, test noise at reference level should produce an SPL of 85 dBC for each of the main front channels (Left, Center, Right) and 82 dBC for each Surround channel . The lower Surround level is specific to film-style mixing rooms.
For television content, test noise at reference level is typically set to produce an SPL ranging from 79 to 82 dBC for each of the main five channels. The lower reference level for television reflects the lower average listening levels preferred by the consumer (typically 70 to 75 dBC).
For music, each speaker channel should be set to the same SPL (just as in television mixing). There is no standard practice for reference levels for music mixing. Some engineers prefer to mix louder than others do, but if the levels between channels are correct, the overall level is not as crucial.
Listening Room Calibration - Measuring SPL
WARNING: Before you turn on a test noise, be sure that your playback system is set to a moderate listening level. Adjust your amplifiers and Beware that if the playback level is very high, you may risk damaging your speakers or possibly your hearing.
To accurately measure SPL:
1. Sit in the reference listening position. Set the SPL meter to “C” weighting and “slow” response.
2. Facing the front speakers, hold the SPL meter at chest level, with the microphone facing up at an angle of approximately 45 degrees to the center speaker. Keep the meter at arms length to prevent measuring audio that may reflect from your body.
3. Keep the SPL meter in this position. Make sure that the meter is aimed at the center speaker as you take readings for the Left, Center, and Right speakers.
4. To take the SPL readings for the Left Surround or Right Surround speakers, keep the meter at the same angle and position as you did for the front speakers. Turn your body 90 degrees from the Center speaker toward the wall closest to the Surround speaker you are measuring. This minimizes “shadowing” or obscuring the meter with your body.
Make adjustments to each individual channel’s trim setting, using your amplifier gain (trim) controls for each single channel to achieve the SPL required for each channel.
The ideal test noise for subwoofer calibration should be band-limited pink noise, lowpass filtered at 120 Hz.
To properly calibrate the subwoofer, a real-time analyzer (RTA) is required. If an RTA is not available, you can approximate the settings with an SPL meter.
When using an RTA, proper calibration requires setting the LFE channel signal to be sent to the subwoofer, within its typical bandwidth of 20-120 Hz, 10 dB higher (as measured by the RTA) than the main channels.
The precision of this measurement varies with the quality of the meter used.
If an RTA is not available, setting the subwoofer channel 4-6 dB higher, as measured by an SPL meter, provides an approximate level. For example, set the subwoofer channel to 89 dBC when the Center channel measures 85 dBC.
Once you’ve achieved SPL calibration using the above technique you’ll have a good starting point for how you may want to tune the room to your own tastes.
I hope this helps!