JapanDave dedicated theater build. - Page 9

Are there 3 aux inputs, L, R and C? I'd definitely use the MC inputs on the back of the amp and switch to MC mode.

Great build man! Wish I would have caught this earlier. I'm interested to see how you solve the pressure problem. I hope that the concrete isn't too big of a factor as that is similar to what my room is. I'll be watching this one.

JD,

Use direct mode. Stereo mode and other modes invoke Audyssey (if enabled) and bass processing whereas direct does not. I have the Integra model before yours and I get a big difference in direct mode vs other modes when measuring with REW. Use the multi-channel inputs for the centre channel but you should be able to use any input on the pre-amp (including the ones at the front) for the left and right.

However, given the grief you're getting with the centre channel, use the multi-channel input for all the speakers so you eliminate any variable but use direct mode!.

Cheers,
Jamie

Firstly, there are two modes for Direct - one with bass, and one without. You might have to do two sets of measurements for each speaker to compare the two modes. To change the mode, hit Menu on the remote. Once the main menu is displayed on the screen or front of the pre-amp, use the down arrows on the remote or front panel to select 3. Audio Adjust and hit Enter, then select Direct, press enter and then select Analog and press Enter and toggle the subwoofer value between Yes and No to get the response with bass signals and without.

Now to connect up to measure with REW, go to the main menu of the Integra (hit Menu on the remote). Select 1. Input/Output Assign and press enter. Once the next menu comes up, press down a few times and select 5. Analog Audio Input and press Enter. Now select Multich and set it to the source (eg. DVD) that you're going to use to measure with REW. Exit the menu and then select the source that you just assigned the Multich input to. Once the appropriate source is selected, press the Audio button on the remote until either Multich or Analog is displayed on the front of the pre-amp.

With the cable, connect the white cable end into either the left, centre or right on the multi-channel input on the Integra depending on which speaker you want to test. When measuring, set REW to use the left channel to measure.

Direct mode is the same no matter whether it's Movie, Music or Game. Just make sure one is selected and a small Direct indicator is lit on the front LCD panel of the Integra.

Cheers,
Jamie

Your LCR and sub plots clearly indicate that Bass Management and the internal Xovers in your pre-pro were not active during the time of the measurement.

Can you hook up the center channel speaker to the left or right channel output on your amp/processor?

I'm not sure what Dennis is trying to test and I haven't followed all of your REW plots. If you are trying to compare the output of the LC&R speakers, playing the same tones off the same channel but to different speakers would do the trick, IMHO.

Just choose Subwoofer on/off for the two modes. I don't have your pre-amp so I was following the instructions in the manual for your pre-amp model (which is very similar to mine).

I don't know why you're not getting the multi-channel direct mode. Your pre-amp is the next model up from mine and it may work differently but normally pressing the 'Audio' or 'Audio Selector' button on the front of the pre-amp should select the multi-channel input once it has been assigned to the specific source you are using.

I think you've pretty much got it. Now measure from your main listening position at your approximate seated ear height to compare with these plots.

Try not to measure from the exact centre of your room (whether that be length, width or height) unless you want to see a ton of dips and peaks in the bass region.

I reached out to some colleagues to come up with some nearfield plots of other speakers for you to compare.

 

30th octave.pdf 27.8212890625k . file

 

document1.pdf 145.224609375k . file

 

Theater NF.pdf 145.3642578125k . file

General Comments:
A pro would use something along the lines of a Quantum Data 780 or Sencore DAG to generate the audio test signals. These devices will output DD or DTS encoded test signals and allow the calibrator to specifically address a given channel. Should a QSC DSP be part of the output chain, each channel's output can be turned off making this process a bit easier.

Pre-Pro in the loop.
It is helpful to keep the pre-pro in the calibration loop. The decoding/processing delays can be noted (has an impact on ITDG and ETG results). As well, it allows the bass management function to be viewed. For example, Bass Management ON, Xover to (80Hz), and then overlay the front channel(s) response over the sub(s) response to view the actual crossover point and the crossover slopes. (Usually not a problem with a THX certified pre-pro. I have seen pre-pros where the slopes are dead wrong and an 80Hz setting is producing a 100Hz xover point.) The only way you can properly match the subwoofer levels with the mains is to do it this way or by a full range RTA live.

Near Field Measurements
Taking near field measurements of the speakers is the first step, always. The near field shows what the speakers are doing and if anything is broken ... like an Xover or a blown tweeter. In the general scheme of things, attempting to fix poor speaker response with an external EQ is not always successful and some response error correction shouldn't even be attempted. In the end, knowing the speaker's response allows you, during room calibration, to separate out what the speakers are doing vs room effects.

Dave, if I understand your circumstances correctly:

1. Your previous speakers in your previous (non dedicated) room did not cause you this hearing distress.

2. Your current speakers in your previous room did cause this distress.

3. Your current speakers in your current room also cause this distress.

From this, it is pretty safe to say the speakers are the culprit. With that in mind, the question is what are the speakers doing that might create this problem for you. You may have developed a sensitivity to distortion in narrow areas of the frequency spectrum. Looking at the near field plots, there are differences between the L, C and R speakers ... the signficance of these differences is difficult to tell without very precise level matching and then an over lay of the three plots. However, they all exhibit a very deep, narrow notch at just below 800Hz, your left is showing something going on at 2kHz (also apparent in the C and R but not as deep), and nasty peak at about 5.5kHz. The notch at 800Hz cannot be addressed by PEQ whilst the stuff at 5.5kHz can be fixed.

I'm rather suspicious of the "stuff" going on at 5.5kHz as being something you could be reacting to ... the 800Hz notch could also be contributing to the issue.

Next steps. I'd suggest you have friends over and see if they have the same issue(s) you have...if not, it could easily be a specific sensitivity in your hearing which has been exacerbated by these particular speakers ... an audiologist may be able to sort this out. As well, the problem you're experiencing could be resolved using different speakers. That's a tough approach because that means listening to other speakers in a geography where this is less than easy to do. I would vote for a visit to an audiologist just to verify your hearing and then listening tests.

Can I ask what you do in Japan? Curious if you are an exPat living there or if you emigrated there? I've always thought it very hard for an 'outsider' to get situated in Japan, as I have understood that the culture is fairly 'xenophobic'.

My own dealings with Japan thru business have reinforced that to some extent, although the younger generation in Japan seems less so.

If you don't feel comfortable saying, thats fine, but I am curious how you got situated over there. (Big assumption being that you weren't born/raised there and moved there recently).

"wish I could have someone closer to do measurements like this for me, but unfortunately I don't. All that stuff you just said went straight over my head."

I agree Dave it can make it near impossible without the right gear & understanding..
There must be someone in Japan with the Knowledge and Gear to fine tune..

Perhaps Dennis may know someone & could put you in touch with them over there, Or better still the man him self ..

If it were me & at all posible I would look at the possibility of working out something with Dennis for further assistance in fine tuning your Theatre
& perhaps renting all the needed components so you can take reliable measurements for Dennis to Analize..

Cheers..

Dave, are you in the military? I was a corpsman in the Navy Reserve and spent 2.5 weeks in Yokosuka. That was a fun experience.

Not sure if your graphs are good or not. I don't know why they are different volumes. I think you can post them on the REW forum for feedback also....though Dennis should be able to help you out.

Andreas ... clearly the speakers are not level matched; however, that is not our current, more pressing issue.

Nice Dave. They look comfortable.
Did the store you ordered them from organize shipping or did you have to do it yourself.
I'm looking at options to get some to Australia.