My first post - Surround back - now you see it now you don't?

[Jarrau]

Hi, I hope I can get some help on this situation.

I have a JVC THX Ultra 7.1 receiver (RX-DP10) which decodes DTS-ES & Dolby - EX.

I have recently installed the two surround back speakers to take advantage of the extra coded sound in the 'back' channel(s).

The strangest thing happens - I bought two DVDs as test discs to try:
1. Revenge of the Sith - Star Wars - which is THX & Dolby Digital EX compatible.
2. GoldMember - DTS 6.1 discrete.

I have the decoder set to 'AUTO Detect' on the receiver.

When I put in the Starwars disc it activates the Dolby digital logo. When the movie starts there is a quick promo for the THX sound which lights up all 7 speakers. This promo goes for about 20 seconds. Then the movie begins and the system drops back to 5.1. I cannot get the surround back speakers to work during the movie? Why is this so?

When I play Goldmember the DTS logo lights but again only 5.1 channels and the surround back speakers are not activated.

Why would the receiver activate all 7 channels during the THX promo and then turn off when the movie starts?
Why would the receiver not activate the surround back channels with a 6.1 DTS movie?
Any tips would be appreciated - it is driving me crazy!

Thx
Ray.

 

[TLS Guy]

Hi, I hope I can get some help on this situation.

I have a JVC THX Ultra 7.1 receiver (RX-DP10) which decodes DTS-ES & Dolby - EX.

I have recently installed the two surround back speakers to take advantage of the extra coded sound in the 'back' channel(s).

The strangest thing happens - I bought two DVDs as test discs to try:
1. Revenge of the Sith - Star Wars - which is THX & Dolby Digital EX compatible.
2. GoldMember - DTS 6.1 discrete.

I have the decoder set to 'AUTO Detect' on the receiver.

When I put in the Starwars disc it activates the Dolby digital logo. When the movie starts there is a quick promo for the THX sound which lights up all 7 speakers. This promo goes for about 20 seconds. Then the movie begins and the system drops back to 5.1. I cannot get the surround back speakers to work during the movie? Why is this so?

When I play Goldmember the DTS logo lights but again only 5.1 channels and the surround back speakers are not activated.

Why would the receiver activate all 7 channels during the THX promo and then turn off when the movie starts?
Why would the receiver not activate the surround back channels with a 6.1 DTS movie?
Any tips would be appreciated - it is driving me crazy!

Thx
Ray.

Can you go into the menu and set up the rear backs manually? I suspect you can.

 

[AVRat]

Are you selecting the appropriate soundtrack on the disk menu? Most movies default to the 5.1 soundtracks.

 

[GlocksRock]

On some movies you have to set the decoders manually, as the discs aren't properly flagged.

 

[Jarrau]

Thanks for suggestions

The rear backs are selected.

I have the right track selected from the disc i.e. DTS or Dolby 5.1 which are the only two surround options.

Why does it all work (7.1) when the THX promo comes on then drop back to 5.1 when the Star Wars movie starts??

More suggestions please as we have not cracked this problem.

 

[fmw]

Why does it all work (7.1) when the THX promo comes on then drop back to 5.1 when the Star Wars movie starts??

Because the sound track is 5.1?

 

[evilkat]

The rear backs are selected.

I have the right track selected from the disc i.e. DTS or Dolby 5.1 which are the only two surround options.

Why does it all work (7.1) when the THX promo comes on then drop back to 5.1 when the Star Wars movie starts??

More suggestions please as we have not cracked this problem.

Jarrau, if you have the option on your receiver, select Dolby Prologic II or DTS Neo 6. I think both of these decoders are matrix decoders, which means it should upconvert your 5.1 soundtrack available in the movie disc to 7.1.

See if that gives you sound through the rear speakers.

 

[adam71]

Are you sure your receiver can decode DTS-ES "discrete" ?? Or just "matrix". Not that matrix is a bad thing since thats all DD-EX is.

Also, keep in mind just because you have this processing doesn't mean the disc will contain info for these channels at all times.

 

[TLS Guy]

Correct description please

I have been trying to help you sort this out. However you have not described your JVC correctly. The JVC site will not recognize anything concerning your receiver in your original post.

Usually I can solve these issues after downloading the manual. Please give details of year and model number for your particular piece of Far Eastern over sold gear.

 

[AVRat]

I have the decoder set to 'AUTO Detect' on the receiver.

Is this the Input mode detection (pg 23) or the THX Surround mode detection (pg 38)?

Have you tried using the THX button on the remote?

 

[Jarrau]

Thanks for all your replies!!

I have looked at all of the above suggestions and are still getting the same results.

My unit is a JVC RX-DP10 -
homecinemachoice.com/reviews/hccreviews/Amplifiers/JVC/JVCRX-DP10.php

From the manual:
THX Surround EX (DTS-ES compatible)
THX Surround EX is a format that has additional left and right
surround back channels on the basis of Dolby Digital 5.1
channels. It improves the definition and the sense of sound
movement in surround (rear) channels.
• This receiver is also compatible with DTS Extended Surround
(DTS-ES)—another multichannel surround containing
additional left and right surround back channels.

When selecting “DIGITAL AUTO,” the following indicators
indicate the digital signal format of the incoming signal.
LINEAR PCM : Lights up when Linear PCM signals come in.
DIGITAL : Lights up when Dolby Digital or Dolby Digital
EX signals come in.
: Lights up when DTS Surround or DTS-ES
signals come in.

More info:
The THX mode does light up THX SURR EX and does project some sound from the surr. back speakers. However I think this is a simulated sound as the extra back speaker symbols that represent a EX or ES signal still are not lit.

Tonight I tried another DVD, the animation 'CARS'. This lit up all the channels including the surr. back. It is a Dolby EX sound track. This was a relief as I thought the receiver was not working properly.

However here is the curious thing. I took the StarWars & Gold Member DVDs to my friend's house. He has a 6.1 EX/ES receiver.
The StarWars Disc performed as it did on my receiver, i.e. it lit up the Dolby EX light only during the THX promo and then went back to 5.1 when the movie started. Even though 5.1-EX was selected on the disc.
Gold Member however did light up the DTS-ES symbol, which it doesn't on my system - still can't understand this one.

Are there many discs that are miss flagged or more sensitive from one receiver to another for decoding? Being digital I thought it would have been on or off - no variation.

At least I have experienced Cars in Dolby - EX. However yet to experience DTS - ES discrete - I will have to try more discs.

BTW I did try a different DVD player on my system, which gave the same results. Even tried both coaxial & optical cables and again the same results.

I hope that different DTS - ES software will trigger the surround back speakers so I can at least be Physiologically satisfied.

Any other suggestions would be much appreciated.

 

[TLS Guy]

Thanks for all your replies!!

I have looked at all of the above suggestions and are still getting the same results.

My unit is a JVC RX-DP10 -
homecinemachoice.com/reviews/hccreviews/Amplifiers/JVC/JVCRX-DP10.php

From the manual:
THX Surround EX (DTS-ES compatible)
THX Surround EX is a format that has additional left and right
surround back channels on the basis of Dolby Digital 5.1
channels. It improves the definition and the sense of sound
movement in surround (rear) channels.
• This receiver is also compatible with DTS Extended Surround
(DTS-ES)—another multichannel surround containing
additional left and right surround back channels.

When selecting “DIGITAL AUTO,” the following indicators
indicate the digital signal format of the incoming signal.
LINEAR PCM : Lights up when Linear PCM signals come in.
DIGITAL : Lights up when Dolby Digital or Dolby Digital
EX signals come in.
: Lights up when DTS Surround or DTS-ES
signals come in.

More info:
The THX mode does light up THX SURR EX and does project some sound from the surr. back speakers. However I think this is a simulated sound as the extra back speaker symbols that represent a EX or ES signal still are not lit.

Tonight I tried another DVD, the animation 'CARS'. This lit up all the channels including the surr. back. It is a Dolby EX sound track. This was a relief as I thought the receiver was not working properly.

However here is the curious thing. I took the StarWars & Gold Member DVDs to my friend's house. He has a 6.1 EX/ES receiver.
The StarWars Disc performed as it did on my receiver, i.e. it lit up the Dolby EX light only during the THX promo and then went back to 5.1 when the movie started. Even though 5.1-EX was selected on the disc.
Gold Member however did light up the DTS-ES symbol, which it doesn't on my system - still can't understand this one.

Are there many discs that are miss flagged or more sensitive from one receiver to another for decoding? Being digital I thought it would have been on or off - no variation.

At least I have experienced Cars in Dolby - EX. However yet to experience DTS - ES discrete - I will have to try more discs.

BTW I did try a different DVD player on my system, which gave the same results. Even tried both coaxial & optical cables and again the same results.

I hope that different DTS - ES software will trigger the surround back speakers so I can at least be Physiologically satisfied.

Any other suggestions would be much appreciated.

Please can you give the complete model number. These are the options I get when entering RX-DP10 in the JVC manual search.
RX-DP10RSL
RX-DP10VBK
RX-DP10VBKJ
RX-DP10VSL
RX-DP10VSLC

I have a feeling the problem my lie in your speaker set up procedure on the JVC, at least partly.

 

[Jarrau]

Thanks for your interest TLS Guy.
Model is RX-DP10RSL

I have found out that the StarWars Return of the Sith disc has a fault with all copies made.
It is stamped all over with THX EX & Dolby EX but only the THX trailer is encoded - the movie is only in 5.1 - apparently this was an error or omission when the DVD disc was made - surprised no else has mentioned this.

I hope the model number helps. Yet to experience DTS 6.1, however I have only tried Gold Member, which does work in 6.1 on my friends system but not mine.