help in analysing a speaker levelling problem

[asraghwa]

Hi,

I am kind of new to operating HT audio systems and need some help, I have recent purchased a NAD pre/Power amp combo and am operating them with my definitive technologies speakers. While setting up the speaker sound level systems from the Preamplifier I found that my front left speaker (floor standing, active) needs to be set up at 7.0 DB to produce same level of sound ( white noise I guess?) as the Front right speaker which is set at 0.0 DB. I have checked the phasing of all speakers and its wired correctly

The question - does it mean something is wrong? if yes than with the speaker or power amp or pre amp?

Thanks in advance

 

[TLS Guy]

Hi,

I am kind of new to operating HT audio systems and need some help, I have recent purchased a NAD pre/Power amp combo and am operating them with my definitive technologies speakers. While setting up the speaker sound level systems from the Preamplifier I found that my front left speaker (floor standing, active) needs to be set up at 7.0 DB to produce same level of sound ( white noise I guess?) as the Front right speaker which is set at 0.0 DB. I have checked the phasing of all speakers and its wired correctly

The question - does it mean something is wrong? if yes than with the speaker or power amp or pre amp?

Thanks in advance

Yes one of the units is faulty.

First switch speakers and see if the side switches, if it does, the quieter speaker is faulty. If it does not change, then it is the pre amp or amp. Now switch the preamp to amp connections over. If the side switches the fault is in the preamp, if it does not the amp is at fault. That will tell you which unit needs to be exchanged.

I assume that you have set the balance control correctly.

 

[asraghwa]

Thanks TLS!!

Appreciate the suggestions, I am not sure what you mean by balance control? I am using M15 and M25 as pre and power amps.

 

[MDS]

7 dB is a pretty large difference but it doesn't necessarily mean anything is wrong. I assume you were balancing the levels using the internal test tones of the pre-amp (pink noise) and an SPL meter. The meter is reading the SPL at the listening position and room acoustics affect how the sound from each speaker reaches the listening position.

My front speakers are both at zero but my center is at + 6 dB, likely because it is lower than the fronts, and that is simply the level I needed to set to balance all the channels. It doesn't mean the center channel of my receiver is faulty.

 

[speakerman39]

As a few others have mentioned, that is a rather large disparity between your mains. Something is wrong. Have you calibrated using a RS SPL meter and a test cd such as the Rives Test CD II? The thing I really like about the Rives is that is has compensation already built in to address the non-linearity of the RS SPL meter. Thus, checking the levels should give you a better idea of where the problem(s) is. Hope this helps and good luck.

 

[TLS Guy]

Thanks TLS!!

Appreciate the suggestions, I am not sure what you mean by balance control? I am using M15 and M25 as pre and power amps.

I didn't realize you had an AV receiver. I thought you had a two channel set up. Every level will be set through the software.

Just play the system as two channel to check it. Select two channel stereo. Play a mono source and see if you have a central image between the speakers. If you do, ignore what the auto system is telling you, and set the speakers the same. If the image is to the louder main speaker then do the tests I suggested.