Best way, if any, to connect LG TV to audio amp ?

luggsie

Active Member
I've just got an LG TV 32LE5900 and wanted to drive an external amp to get simple stereo. I'm testing with a Typhoon 5.1 amp with optical, coax and component inputs. After some hours messing with cables and connectors I get the following "features", probably something to do with copy protection

1. The TV ouputs optical audio when fed with HDMI, under some conditions, eg. I can use a Sony HDD recorder as a DVD player or replay analogue TV programs prerecorded off air. But there is no AV audio o/p from the TV.
2. If the HDD recorder input is switched to the AV signals from a SKY box for direct feedthrough onward via HDMI, the TV gives no external audio signal outputs from any sockets (its internal speakers are OK).
3. TV outputs AV audio from AV1 SCART socket when fed from its own RF antenna input derived from the same SKY1 box but then there is no optical output option.
4. There is no way to get any audio output from the TV when it is fed with AV inputs (eg cables from the same SKY box).

A LG 19LD350 TV works in exactly the same way so I don't think it's a TV fault. It *always* puts audio out from the headphone socket, but quality is not so good and it may be mono.

Is the way forward to get an AV (L, R audio plus composite video) to HDMI converter. If so what to get and is this guaranteed to fool the TV into thinking it has a digital input so I can consistently get an optical audio output from the TV for all types of input ?


luggsie
 

PSM1

Distinguished Member
If you have an AV reciever then you should connect all the sources direct to the reciever and not via the TV. This would get around all your issues and give you sound from all sources.
 

luggsie

Active Member
thanks, an AV receiver seems the (expensive) way to go. In the meantime it inspired the idea of tapping the audio off the TV inputs instead of outputs as a workaround. I just checked the audio delay in the TV and there doesn't seem to be any, so there wouldn't be a lip-sync problem.

luggsie
 

Mark.Yudkin

Distinguished Member
Your main problem is that you bought a TV that doesn't have analogue audio outs, and digital output from HDMI sources is proscribed by HDCP (HD Copy Protection).

However, your LG has a headphone output, and you can use that to work around the issue for stereo signals. You need a 3.5mm stereo jack - 2 x RCA connector. You'll need to use (near) maximum volume.

The optical output should work for non-HDMI sources, including its builtin tuner(s), so check it's enabled in the menus and that the cable is functional , specifically that you haven't destroyed the cable by over-bending, something that is trivial to do even when being extremely careful.

For surround sound through your Typhoon, you'll be best off using the optical connection from the source(s) (DVD, Sky).
 

luggsie

Active Member
that not quite correct, there is an analogue o/p on AV1 but it's *only* enabled when the signal source is the RF antenna ! The optical output is only enabled when the input is HDMI but then not always. Feeding analogue AV through the Sony HDD recorder to its HDMI connection to the TV produces no optical but if the AV is recorded on the Sony and then played back, it does enable the optical. So both the Sony DVD and the LG TV are playing tricks with functionality.
There don't seem to be any menu options to enable outputs though I heard of a hidden setup menu yesterday.

I think its all a conspiracy to sell more AV receivers.

luggsie.
 

luggsie

Active Member
After a lot more testing, the Typhoon amp seems a bit dodgy and sometimes is not locking onto its optical input. This explains some of the apparent lack of audio outputs from the TV. An elderly Sherwood AV receiver always works on the optical o/p from the LG TV which is, of course, perfectly in lip sync with the picture.
Just as well as the audio delay in the TV is a substantial 130ms, a bit beyond most AV receiver audio sync adjustment range AIUI. Not sure if the TV supports audio feedback through HDMI as it isn't listed in the spec. so one way forward is to get an HDMI AV receiver with a big sync delay range.
 

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