Physical central channel vs phantom center - Odd behaviour

A

Andrein

Senior Audioholic
Hi everyone.

After about 7 years since I built my current 4.2 system I decided to add a central channel mostly for movies dialogue but also for multi channel music. Have been using phantom center so far and was happy except some movies where voice might be a bit difficult to hear

Haven't gotten to movies yet but found something weird with music.

When I switch central channel setting from none to small in my avr (Yamaha a1070), I notice that a lot of content goes to central channel from fronts and overall sound stage changes. It is becoming more 3 dimensional but with focus on center. Also I would say that mids become less pronounced and I think amount of bass gets lower. This happens when I use 2 channel music upmixed to 5.2 using Dolby Surround. In some DSP modes it is more noticeable than in others but happens with all DSP modes. Have not yet tried true multichannel content.

Central channel spread function does not help. It does nothing in my case it seems.

All channels are level matched and distance calibrated by ypao.

Any ideas why I might get this?

My setup - Yamaha a1070, Anthem MCA 525, Fronts - Proac 148, Rears - Proac 118, Center - Proac Central Voice, 2x svs SB2000
 
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TLS Guy

TLS Guy

Seriously, I have no life.
Hi everyone.

After about 7 years since I built my current 4.2 system I decided to add a central channel mostly for movies dialogue but also for multi channel music. Haven't gotten to movies yet but found something weird with music.

When I switch central channel setting from none to small in my avr (Yamaha a1070), I notice that a lot of content goes to central channel from fronts and overall sound stages. It is becoming more 3 dimensional but with focus on center. Also I would say that mids become less pronounced and I think amount of bass gets lower. This happens when I use 2 channel music upmixed to 5.2 using Dolby Surround. In some DSP modes it is more noticeable than in others but happens with all DSP modes. Have not yet tried true multichannel content.

Central channel spread function does not help. It does nothing in my case it seems.

All channels are level matched and distance calibrated by ypao.

Any ideas why I might get this?

My setup - Yamaha a1070, Anthem MCA 525, Fronts - Proac 148, Rears - Proac 118, Center - Proac Central Voice, 2x svs SB2000
What sound mode are you using? There are a variety of up mixers. All except DD surr are awful in my opinion.
Go to pages 66 and 67 of your manual, and see how to change sound modes, and make sure you have DD Surr selected.

If that does not help, get rid of YAPAO. Just use it for distance and levels. Switch off Eq. functions. I only use Audyssey for levels and distance and nothing else. I have heard YPAO is the worst of the lot, and would certainly never let it Eq any system of mine.
 
A

Andrein

Senior Audioholic
What sound mode are you using? There are a variety of up mixers. All except DD surr are awful in my opinion.
Go to pages 66 and 67 of your manual, and see how to change sound modes, and make sure you have DD Surr selected.

If that does not help, get rid of YAPAO. Just use it for distance and levels. Switch off Eq. functions. I only use Audyssey for levels and distance and nothing else. I have heard YPAO is the worst of the lot, and would certainly never let it Eq any system of mine.
All DSP modes have the same problem. I tried DD Surround and Standard which I use most. I used ypao just to get levels and distances just like you. Then manually put them in Manual configuration. So no EQ is enabled
 
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TLS Guy

TLS Guy

Seriously, I have no life.
All DSP modes have the same problem. I tried DD Surround and Standard which I use most. I used ypao just to get levels and distances just like you. Then manually put them in Manual configuration. So no EQ is enabled
In that case I suspect you are playing music in the popular domain. You never play 2 channel pop music via an upmixer as it always goes to the center channel. Classical music on the other hand is recorded with a wide spectrum of left right information. Pop recordings are all close to double mono in my experience.

I have Wav.Lab 6 loaded on my DAW in the HT room. I can look at the information and see the direction of all sounds on a moment to moment basis. Pop music stays very close to the vertical central axis, whereas classical music had "dancing" circular lines encompassing the whole screen. If I have to work, with and master pop recordings, I never use the upmixer. The problem is not with your equipment, but with the cloth eared engineers who record and mix that genre of music.
 
A

Andrein

Senior Audioholic
In that case I suspect you are playing music in the popular domain. You never play 2 channel pop music via an upmixer as it always goes to the center channel. Classical music on the other hand is recorded with a wide spectrum of left right information. Pop recordings are all close to double mono in my experience.

I have Wav.Lab 6 loaded on my DAW in the HT room. I can look at the information and see the direction of all sounds on a moment to moment basis. Pop music stays very close to the vertical central axis, whereas classical music had "dancing" circular lines encompassing the whole screen. If I have to work, with and master pop recordings, I never use the upmixer. The problem is not with your equipment, but with the cloth eared engineers who record and mix that genre of music.
Ok, but isn't the purpose of DD Surround's central channel spread feature to fix this? Why isn't it working? Also, why does it affect the bass too?
 
TLS Guy

TLS Guy

Seriously, I have no life.
Ok, but isn't the purpose of DD Surround's central channel spread feature to fix this? Why isn't it working? Also, why does it affect the bass too?
That is because the program is too close to mono. So when you enable center spread you just send mono to all three speakers, and so it all sounds central no matter which speakers you send it too.

I can bet your program material is very sparse on left right information and center centric from the mix.

Just listen to it in two channel stereo, and forget using the center when playing it.
 
A

Andrein

Senior Audioholic
I remember Gene saying Central spread is a good feature. But I see no effect from it at all. On any content. There should be some difference at least between it on and off. I am not getting mono, but I like sound without center more. I guess without center avr splitting center channel material between front speakers creating a wider central stage. I would expect a similar thing with Central Spread.
 
TLS Guy

TLS Guy

Seriously, I have no life.
I remember Gene saying Central spread is a good feature. But I see no effect from it at all. On any content. There should be some difference at least between it on and off. I am not getting mono, but I like sound without center more. I guess without center avr splitting center channel material between front speakers creating a wider central stage. I would expect a similar thing with Central Spread.
I have done careful measurements on all this with test tones. These systems of which DD Surr is the best work mainly on interchannel phase differences, but also intensity.

They do not work at all well unless there are significant phase differences, which translates to timing differences, between the channels. These programs do not work well with bad mixes, which are the rule in the pop world. I never engage these programs in music from the pop culture.

For good classical recordings it works superbly. For the rest I switch to two channel.

You will find it works well in discrete multichannel recordings.
 
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T

Trebdp83

Audioholic Ninja
I remember Gene saying Central spread is a good feature. But I see no effect from it at all. On any content. There should be some difference at least between it on and off. I am not getting mono, but I like sound without center more. I guess without center avr splitting center channel material between front speakers creating a wider central stage. I would expect a similar thing with Central Spread.
The Yamaha RX-A1070’s Dolby Center Spread is only functional when playing two channel signals using Dolby Surround with Center Spread ON. It should spread vocals out evenly to the front channel speakers when working properly.

The loss of bass using the center channel speaker set to SMALL is presumably the result of a crossover setting for the center channel that is too low. YPAO will most likely have set the crossover settings of each speaker at or close to its basement.This will result in the subs not doing what they could and should be doing for you regarding two channel signals.

ALL of the speakers should be set to SMALL with the Extra Bass setting OFF. Set the crossover settings anywhere from 120Hz to 80Hz. Experiment with it and you will find your own sweet spot for each of them. Have fun with it and prepare yourself for the PB 2000 recommendations.;)
 
A

Andrein

Senior Audioholic
I have done careful measurements on all this with test tones. These systems of which DD Surr is the best work mainly on interchannel phase differences, but also intensity.

They do not work at all well unless there are significant phase differences, which translates to timing differences, between the channels. These programs do not work well with bad mixes, which are the rule in the pop world. I never engage these programs in music from the pop culture.

For good classical recordings it works superbly. For the rest I switch to two channel.

You will find it works well is discrete multichannel recordings.
Tried few DTS and Dolby Surround Audio DVDs. They sound much better with Central channel enabled than when I run upmixed against 2ch source. No reduce in bass this time. I guess for multi channel music and movies I will use central speaker but for 2ch upmixed will use phantom center. Especially because I can't see central channel spread doing anything in my system. Maybe I need to try factory reset.
 
isolar8001

isolar8001

Full Audioholic
Also, any "Virtual" speaker functions can affect the center spread effectiveness.
Sometimes you get lucky with any of these AVR's, and two channel sources sound good....mostly it's a crap shoot.
Sometimes, I just say the hell with it and set to 4.1 config...problem solved.
 
A

Andrein

Senior Audioholic
The Yamaha RX-A1070’s Dolby Center Spread is only functional when playing two channel signals using Dolby Surround with Center Spread ON. It should spread vocals out evenly to the front channel speakers when working properly.

The loss of bass using the center channel speaker set to SMALL is presumably the result of a crossover setting for the center channel that is too low. YPAO will most likely have set the crossover settings of each speaker at or close to its basement.This will result in the subs not doing what they could and should be doing for you regarding two channel signals.

ALL of the speakers should be set to SMALL with the Extra Bass setting OFF. Set the crossover settings anywhere from 120Hz to 80Hz. Experiment with it and you will find your own sweet spot for each of them. Have fun with it and prepare yourself for the PB 2000 recommendations.;)
All my speakers are small with 80hz crossover which should not be too high for any of them. I like how the system sounds but would like to see how central speaker changes the sound. Especially in movies as sometimes I have trouble to understand what people are saying. I don't use yao except for levels and delays measuring. Generally have no issues with bass in my small room. So 2 sb2000 are more than enough for me))) I will try ported in my next house even if I don't need them. Just for the sake of science at least)))

I found some other weird thing. Changing crossover freqs or small to large or vice versa does not seem to have effect on the sound any more. Suspect this is another reason for factory reset((( I did last calibration few firmware updates ago. So maybe some stale configs causing the problem.
 
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A

Andrein

Senior Audioholic
Also, any "Virtual" speaker functions can affect the center spread effectiveness.
Sometimes you get lucky with any of these AVR's, and two channel sources sound good....mostly it's a crap shoot.
Sometimes, I just say the hell with it and set to 4.1 config...problem solved.
Do you use virtual speakers?
 
A

Andrein

Senior Audioholic
No...many AVR's have that as a default setting though. Best I can make of what they do is something similar to upmixing.
To be honest I haven't noticed virtual channels doing much myself but physical Vs phantom ventral channel without center spread option working gives a huge difference
 
isolar8001

isolar8001

Full Audioholic
To be honest I haven't noticed virtual channels doing much myself but physical Vs phantom ventral channel without center spread option working gives a huge difference
Lots of interactions between all the trickery used on AVR's when it comes to upmixing 2 channel.
You can drive yourself crazy finding a stable solution that you are happy with....then it all changes based on the recording just like TLS Guy has said.
Good thing remote buttons are fairly durable.
 
A

Andrein

Senior Audioholic
Lots of interactions between all the trickery used on AVR's when it comes to upmixing 2 channel.
You can drive yourself crazy finding a stable solution that you are happy with....then it all changes based on the recording just like TLS Guy has said.
Good thing remote buttons are fairly durable.
Yeah. More things to remember. Time to add chat gpt to the receivers)))
 
F

fmw

Audioholic Samurai
Ok, but isn't the purpose of DD Surround's central channel spread feature to fix this? Why isn't it working? Also, why does it affect the bass too?
Stereo wasn't designed with a center channel. Stop using it for music. Your receiver should have a stereo mode. That should turn off content going to the center channel. My receiver does. Use stereo mode for music. Use video sound track modes only for video sound tracks.
 
A

Andrein

Senior Audioholic
Stereo wasn't designed with a center channel. Stop using it for music. Your receiver should have a stereo mode. That should turn off content going to the center channel. My receiver does. Use stereo mode for music. Use video sound track modes only for video sound tracks.
I want to use Dolby Surround upmixer for music. I am not hide hard 2ch guy))
 
isolar8001

isolar8001

Full Audioholic
I want to use Dolby Surround upmixer for music. I am not hide hard 2ch guy))
Yeah....a lot of 2 channel sounds good upmixed. There are just those occasional tracks/albums that want to direct everything to the center.
What is your music source ? Sometimes certain modes are disabled on an AVR depending on the source.
This might be why center spread doesn't seem to work for you.
 
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