Sony STRDB790 AFD = No Pro Logic on Cable?!

digitaldave

Active Member
I've just got a Sony STRDB790 receiver, and I've noticed that if I use 'AFD Auto' with my NTL cable, I only get stereo sound. The same if I select 'Dolby Pro Logic'. The only way to get the rear channels to output something is to use DPL2 or DTS Neo :confused:. However, things seem to work perfectly with a DVD. Any ideas what's going on? Is this a 'feature' of the STRDB790' ?;)

Thanks,

Dave.
 

bob1

Well-known Member
That sounds normal ,afd is detecting a stereo input so is going into stereo.IT will only detect any other fomat when fed with a digital input like a dvd player.
 

digitaldave

Active Member
Bob,

Thanks for the reply :smashin:.

Now that I think about it, your explanation makes sense. I guess I'll leave it in DPL2 mode for TV then, and let the digital sources auto select.

Next question, why do DD soundtracks appear on the front panel aas 'Dolby Digital 3/2.1'??? I know that it adds up to 5.1, but wouldn't it be easier to just list it as 5.1?

Thanks,

Dave.
 

bob1

Well-known Member
Originally posted by daveabrey


Next question, why do DD soundtracks appear on the front panel aas 'Dolby Digital 3/2.1'??? I know that it adds up to 5.1, but wouldn't it be easier to just list it as 5.1?

Thanks,

Dave.
Yes it would be easier its just the way they have done it,there might be a reason for it but i don't know what it is.
 

clayts450

Member
IT's so you know whether the rear channel is discrete or matrixed in, I think :)

e.g. Se7en (dts ES Discrete) shows as dts 3/3.1, normal dts or ES Matrix (eg Gladiator) shows as dts 3/2.1 etc

Does anyone else get virtually no output from the subwoofer on ProLogic 2 or is it just me ? I'm sticking with dts Neo 6 (no separate .1 channel)
 

digitaldave

Active Member
Sorry for dragging this up again, but I've recently dropped ntl for Sky+. I'm using the optical connection to the STRDB790, and it still only decodes stereo using AFD - I thought it would pick up a pro logic signal. Does this mean that Sky doesn't even transmit pro logic on normal TV? I know that you get DD on some movies, but I'd assumed you'd get pro logic :confused:.
 

Lester

Active Member
Sky, Terrestrial etc. are broadcasting a stereo signal (even though some programmes contain Pro Logic information). So "AFD" will simply detect this and send stereo to the speakers.

By selecting "Normal Surround" you're asking the amp to decode any Pro Logic information and then reproduce it according to which flavour you prefer (PL, PLII Music or Movie).

At least that's how I think it works on my Sony amp. :smashin:
 

digitaldave

Active Member
Lester said:
Sky, Terrestrial etc. are broadcasting a stereo signal (even though some programmes contain Pro Logic information). So "AFD" will simply detect this and send stereo to the speakers.

By selecting "Normal Surround" you're asking the amp to decode any Pro Logic information and then reproduce it according to which flavour you prefer (PL, PLII Music or Movie).

At least that's how I think it works on my Sony amp. :smashin:
But I would have thought that if the signal contained a Pro Logic mix, then AFD would pick it up? Maybe I just haven't found anything that's actually coming through in pro logic :D.
 

Cable Monkey

Novice Member
Pro Logic is totally passive. The only way I know for an amp to auto switch is if it is transmitted on a Dolby Digital 2.0 signal with the pro logic flag set. The amp will then autoswitch (my Sony does anyway). Otherwise it is set to pro logic as a default and will switch to DD if it detects it.
 

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