Playing an LPCM quad track on a 5.1 system

Help Support QuadraphonicQuad:

jimfisheye

1K Club - QQ Shooting Star
Joined
Jan 8, 2010
Messages
1,885
Some AVRs and some media player apps as well turn out to only be programmed to recognize 2.0 or 5.1. This is not proper or to spec but it's a thing.

Good instructions above. :)
Just wanted to chime in with a sanity check. There really is a bug in some AVR firmware and some media player apps! (Yes bug! This is not to spec.)
 

Ninecats

800 Club - QQ All-Star
Joined
Jun 23, 2015
Messages
840
Location
Sweden
isn’t adding a silent LFE and Center an Ok solution to AVRs that only play 2.0 and 5.1? That means the files have to be ripped.
 

KMO

Active Member
QQ Supporter
Joined
Nov 14, 2006
Messages
68
Its the Sony . . my X800 wont play the Quad...i have to use my Oppo
The X800 outputs LPCM as-is. If it's 4.0 on the disc, it's 4.0 on the HDMI.

This works fine for me with the X800M2 and a Denon AVR-4308.

This is valid behaviour from the X800M2. 4.0 LPCM is a valid format for HDMI.

I believe the Oppo will reformat certain layouts before sending them over HDMI. You normally don't want a player to do that - it would be very bad in some cases - adding empty channels to 2.0 would stop Pro Logic II working, and adding empty channels to 5.1 would stop Pro Logic IIx working.

But if it converts 4.0 to 5.0 (Or 5.1?) then that potentially works around these receivers that don't handle 4.0 correctly, with no down-side I can immediately think of. (Receivers don't have any special processing for 4.0, such as Pro Logic II on the front channels only)

So it's the receiver that's faulty, the Sony X800 working correctly, and the Oppo incorporating a workaround for faulty receivers.
 
Last edited:

KMO

Active Member
QQ Supporter
Joined
Nov 14, 2006
Messages
68
isn’t adding a silent LFE and Center an Ok solution to AVRs that only play 2.0 and 5.1? That means the files have to be ripped.
Are there any receivers that don't handle 5.0? Surely that's common enough? But then I would have said that about 4.0 until hearing of this fiasco...
 

Ninecats

800 Club - QQ All-Star
Joined
Jun 23, 2015
Messages
840
Location
Sweden
Are there any receivers that don't handle 5.0? Surely that's common enough? But then I would have said that about 4.0 until hearing of this fiasco...
There sure is, mine for instance, it handles 4.0 and 5.1 but if I want to play a 5.0 mix I have to rip the discs and add a silent LFE, else I get 2.0.
 
  • Wow
Reactions: KMO

AshBuchanan

Well-known Member
QQ Supporter
Joined
Sep 25, 2018
Messages
108
Location
Cumbria
I'm trying to play the Quadrophonic mix of Wish You Were Here by Pink Floyd from the Blu Ray that comes in the Immersion Box Set. It's in LPCM on the disc
I had the same problem, but luckily in the case of WYWH and DSOTM, the quad mix on the dvds is in dolby and plays fine
 

madscot

Member
Joined
Sep 24, 2020
Messages
44
Location
UK
Good to know, i have never touched the dvd’s, will give them a try later today, thank you
So, an update, I played both 4.0 mixes on the dvd’s, my receiver will play them in direct mode only, at first it was playing them through all speakers in multi channel mode and I thought this is the same as the blu ray, for anyone else struggling with the same problem try the dvd with direct mode
 
Top