Any Audio Experts Out There?

[AlanHo]

Because I have hearing disability I can only hear the TV audio if it is on ultra loud. Far too loud for my wife and our neighbours. I therefore use Sennheiser RS 120 II RF Wireless Headphones plugged into the headphone socket on the TV. My TV was a Toshiba WL66 42 LCD HD bought in 2006 which was connected to a vintage Sony music centre via SCART to output the TV audio through the Sony surround sound speaker system. (The Sony unit sends DVD video to the TV by HDMI cable).

I have just purchased a Panasonic Viera TX-L42E5B to replace the Toshiba TV (which went belly up) and connected it up in the same way to output audio through the Sony music centre. With my previous TV this worked perfectly but with the new TV there was a lag between the Headphones and TV speakers so that I could hear the headphones (and more quietly) the TV audio speakers out of sync. It is as if there was a timing difference between the speaker output and the headphone output from the TV. The difference was slight, but the ‘echo’ was off-putting. I am not sure which sound track lagged behind the other. The problem existed when I used just the in-built TV speakers (which incidentally are not muted on the new TV automatically when headphones are plugged in) – and when I connected the Sony music centre. Although I normally used wireless headphones, I tried wired ones, and it was the same problem.

I tried various ideas suggested by the retailer without success and assumed that the Sony system was the culprit. Hence I purchased a Panasonic Home Theatre Audio System model SC-HTB20 which is connected to HDMI 2 on the TV (ARC). The SCART connection to the Sony music centre was disconnected and the headphones are still plugged into the TV headphone jack. Hence TV sound is now through the Panasonic home theatre system and DVD’s Radio etc play on the Sony music centre surround sound speakers.

I am disappointed to discover that the 'echo' problem still exists and I am mystified why the old Toshiba TV worked fine and the new Panasonic does not.

It does not appear to result from feedback through the wiring – because if I mute the TV audio – the headphone soundtrack is fine. I am obviously picking up the room noise as well as the headphones which previously must have been in perfect sync for me not to have noticed it with the Toshiba TV. My wife has also tried the headphones and confirms she gets the same “echo” (thus frustrating any attempt by anyone to suggest the echo is reverberation in my empty head).

Is there anything that I can do to eliminate the “echo” heard in the headphones?

I have Emailed Panasonic for advice and await their response – but I “aint” holding my breath.

[AlanHo]

Some additional info in case it is relevant :- The Woofer enclosure contains the Audio electronics. It is connected to the TV by an HDMI cable via HDMI-ACR ports (I don't know what this means - but one of the 4 HDMI ports on the TV is marked ACR and you have to connect the sound system to that port). The sound bar stereo speakers connect to the woofer/control unit with a pair of standard twin loudspeaker wires. There is no headphone socket on the sound system - hence I have to use the one on the TV. I would not trust myself to try and connect to the internal circuitry to make a headphone connection.

The TV speakers are not muted when headphones are connected - this is done using the remote in the TV menu system. Similarly - the home theatre speakers are not muted when the headphones are connected - this is done on the remote using the mute button.

Note that the TV remote controls the sound system when connected via an HDMI ACR socket (which it is).

Headphones

http://tinyurl.com/2cgmedk

Audio System

http://tinyurl.com/ansvdoa

Television

http://tinyurl.com/7m6j4ue

[Gandalph]

OK Alan, and this is just a guess, has the new Telly have an Optical coupling to the Surround sound system. If it has try that and see if there is any difference. The Telly I think will definitely have an optical coupling plug on the back.

[AlanHo]

I will purchase an optical lead to see it that helps as an experiment; but there is a downside.

If I connect the TV to the sound system other than by HDMI-ARC, I lose the Panasonic Viera link which enables me to control the sound system with the TV remote. At present the TV switches the sound system on and off automatically and the TV remote can be used to mute the sound and alter the sound settings. I could probably put up with using two remotes but my wife would find it irritating.

[AlanHo]

I have now tried using an optical lead - but the problem remains.

As a pure amateur my guess is that the TV circuitry is such that there is a small timing difference or latency between the HDMI outputs and the output to the optical and headphone sockets.

The problem did not occur with the original TV so it must be the new TV that is the root cause.

[Gandalph]

Sorry Alan, it was worth a try as "according to the books' an Optical sound coupling is faster than other couplings.

[MANEMAN]

I have had a word with Alan on the telephone about his problem since he posted, and come up with a few ideas as to what could be the cause of his problem. Since I spoke to him I have also managed to download the manual for his TV and sound system to give me a better view of things.

To my mind this is a digital / analogue delay problem, the Home Cinema system receiving a digital signal from the TV, whilst the headphones are receiving an analogue input.

One of the problems here is knowing exactly how Panasonic sourced the analogue audio for the headphone socket. Either as pure analogue, - or perhaps as digital audio converted to analogue ?

Which ever way it is done it would seem that Panasonic did not envisage someone listening with headphones whilst having the main speakers on as well.

As Alan is awaiting a reply back from Panasonic we of course firstly await their take on the problem.

This could well be a design fault for which there will be no cure other than to spend time, thought, and a little money to put right. It could maybe take just a press on the remote in "Sound Settings" to find some sort of audio juxtaposition where everything drops into place and starts to sync, or It may be as Gandalph has suggested worth trying an optical audio lead. With audio delays such as this measured in milliseconds, anything is worth a try.

I have suggested to Alan that he could purchase an HDMI Digital-to-Analogue converter and feed the headphones from that. But, if that is the way that Panasonic have already sourced the headset jack on the TV anyway, the delayed audio problem may still exist. It really is a "Suck it and see" scenario if Panasonic don't come up with any answers. ( http://www.amazon.co...pd_sim_sbs_ce_4 )

I will just mention Alan that on Page 40 of the Manual you will see reference to turning On/Off NICAM Stereo.

Can you try that in both positions and let us know if that makes a difference ? In fact you can have a twiddle with all in there because it has got a "Reset to Defaults" option.

Since looking at the manual for the Home Cinema setup I can see that making up a couple of headphone sockets by wiring them into the speaker wires is probably going to be a "No-Go" also without the wiring diagram for the speakers.

What you are up against is Hi/Lo filters for Bass and seperation, plus the digitalisation with the lip sync delay and the

ARC circuitry. Wiring to the two upright thin speakers only, would give you a very limited range of frequency at the headset.

Wonderful the digital world init ? I used to get ghosting on the old analogue TV, now I get full on digital blocking. Always had a good bitrate on FM radio, now with DAB the bitrate is crap, and there are loads of serviceable analogue satellites flying around in space broadcasting bugger all !! - Moan....Mumble....Bloody............Governm...... :)

Let us know how you get on Alan.

John.

[Gandalph]

If the Headset is Analogue and obviously being used with a digital output, that could also be the problem. A bit rate mismatch on the conversion side. I would try and borrow a pair of Digital headphones (preferably cordless) and try them to see if that would correct the problem.

[AlanHo]

I will just mention Alan that on Page 40 of the Manual you will see reference to turning On/Off NICAM Stereo.

Can you try that in both positions and let us know if that makes a difference ? In fact you can have a twiddle with all in there because it has got a "Reset to Defaults" option.

The menu system on the TV varies according to the equipment that is connected and other factors. For some reason the NICAM setting does not show up - it being associated with analogue stuff that is connected. In addition - when the panasonic sound system is connected the only settings available are, headphone volume, voice guidance and reset to default. I presume it knows there is a sound system connected and assumes that the external sound sysytem will provide all the modes and settings. In the case of the Panasonic sound bar I am using - this is restricted to volume, bass level, mute, dialog effect and a choice from 3 surround sound settings.

I have tried all the permutations without success.

If the Headset is Analogue and obviously being used with a digital output, that could also be the problem. A bit rate mismatch on the conversion side. I would try and borrow a pair of Digital headphones (preferably cordless) and try them to see if that would correct the problem.

I don't have any known source for the loan of digital headphones. In fact, I had no idea such a thing exists. The question then is - if I find a source, how are these connected to the TV?

[Gandalph]

Exactly the same way as you analogue set.

[AlanHo]

I have already tried connecting direct wired headphones to the TV which produced the same echo as my current analogue wireless headphones. Are digital headphones really going to be any different with regard to signal synchronisation with the speakers. If so - why? A dumb question perhaps but having looked at the price of digital headphones of any quality I would need to be very sure of success before I raided the piggy bank to that extent.

I have found several threads on various forums about the same problem - but without any proven solutions. I am surprised because there must be lots of couples with a similar problem. I first posted the question on the AV forum which specialises in Home Entertainment equipment. My post has received 66 views but not a single response. Hence I am bound to conclude that this is going to be a tough one to crack.

My present feeling is that the least expensive solution is to use closed headphones to prevent leakage of room noise and for us both to attend a semaphore or deaf signing course so that we can communicate when watching TV.

[Gandalph]

That is why I suggested you try and borrow a pair before you went and purchased some. They may or may not solve your problem.

I have a pair of Philips cordless headphones that I used to use when my wife was alive. When she was asleep I used to pop them on to save waking her up and they worked flawless. They are analogue but the Stereo was absolutley brilliant through them with no latency either. All I could hear was the television and nothing else. I could see the bedroom from the lounge and used to check about every five minutes to make sure she hadn't woken up and was calling me, because if she had I wouldn't have heard her.

[MANEMAN]

Alan has already got some wireless headphones Gandalph.

Alan Said: I therefore use Sennheiser RS 120 II RF Wireless Headphones plugged into the headphone socket on the TV.

The problem as I see it is that the only audio source for headphones on this Panasonic TV is analogue, and whether the headset used is wireless or hard-wired, the resultant audio signal heard is going to be "different" from the one heard from the speakers. - Different in as much as one or the other of the signals has a slight delay. (Latency)

If proved that the headset signal was arriving before the sound from the The Home Cinema speakers, it would be viable to feed the headphone out socket into a headphone Pre-amp with variable electronic delay. This is where things can start to get a bit pricey ! ( http://altomusic.com...er_pid115866.am ) I suspect this unit is Mono only as well !

There are cheaper alternatives to applying delay to an analogue signal, but unfortunately most manufactured delay systems seem to cater for musicians rather than the home user. A stereo delay for headphones could be built very cheaply if anyone wanted to spend time building two of these: http://electronicdes...-uses-1-bit-adc

Experimentation at this level means either buying or building "Hardware", that may or may not work. :(

But.................. If you were to feed the output from the headphone socket into a (Spare) computer and plug the headphones into the output of the computer, - things become cheaper and a lot easier. There is a lot of free variable sound delay software available. The following VST Plugin used with a player like Winamp or similar would probably solve the problem: http://www.voxengo.c...uct/sounddelay/

Well. That is me all thought out for today Alan. :D

Stuffing some cottonwool in Libby's ears and turning the volume way up as you suggested seems a lot less complex.

I did suffer my own latency problems between my piano / guitar and output which I wrote about on the forum here a while back. Managed to cure that by installing "asio4all" though.

Keep us updated Alan. Here is a picture of the VST delay (Free !) :

[AlanHo]

Bloody 'ell - do you need a pilots license for that beast?

Thanks for the thoughts - I am going to put the problem on the back burner until I hear from Panasonic. (I will give them 7 days to answer - if not - I will hit the phones).................(telephones not headphones)

[AlanHo]

I have resorted to a temporary cludge pending any advice from Panasonic.

I have stuck some black duct tape over the outside of each headphone ear piece to (sort of) convert them to almost the closed type. It has cut down the echo dramatically and there is just enough noise leakage from the room to allow my wife to gain my attention if necessary.

Heath Robinson I know - but needs must.

[Gandalph]

Any word from the Panasonic front yet Alan?

[AlanHo]

Any word from the Panasonic front yet Alan?

Not yet.

I sent them my message using the contact form on the UK Panasonic web page on the 25th January.

A couple of guys on another forum advised me from experience that if I get a reply - and it's a big fat IF - it will take about a month.

Meanwhile I have found that if my wife has the TV sound on at a low setting (just high enough for her to hear) and I have the volume on the headphones fairly loud, the echo - though just detectable - is not intrusive.

[rong]

If there's an echo I take it one of you is out of sink with the mouths of people speaking, if so do you have a sink setting in your sound settings that you can adjust slightly th place it between the two of you. I say this as my Samsung telly or surround system has this. Cant remember which it is though.

[Gandalph]

Any word from the Panasonic front yet Alan?

Not yet.

I sent them my message using the contact form on the UK Panasonic web page on the 25th January.

A couple of guys on another forum advised me from experience that if I get a reply - and it's a big fat IF - it will take about a month.

Meanwhile I have found that if my wife has the TV sound on at a low setting (just high enough for her to hear) and I have the volume on the headphones fairly loud, the echo - though just detectable - is not intrusive.

Well if it takes them a Month to reply, if at all, they must be having a hell of a lot of e-mails sent to them. Either that or they must be trying to replicate the problem to come up with a solution.

[AlanHo]

Panasonic have at last replied to my complaint as follows :-

Dear Mr. xxxxxxxxxx,

Thank you for your email regarding your Panasonic product. We appreciate that you have kindly taken the time to write to us with your enquiry.

Due to the complexity of your request, your details have been forwarded to our specialist team for further investigation.

Please rest assured that you will be contacted by a member of our team, as soon as a resolution to your enquiry becomes available.

In the interim, We hope this information has been of some assistance to you.

Kind Regards,

Ray L

Customer Service Team

Panasonic UK

--- Original Message ---

FROM:[email protected]

SENT:26/01/2013 15:01:00

To:UK_Panasonic HOME ENTERTAINMENT-Mailbox

SUBJECT:WEBFORMEMAIL /HOME ENTERTAINMENT/WEBFORM/EMAIL/HE/1/2<

Enquiry Number: 112816-1359212363

Customer name: Alan xxxxxxxxxxxxxxx

TEL: xxxxxxxxxxxx

Message: I have just purchased a Viera TX-L42E5B to replace a 6 year old Toshiba LCD TV which was connected to a Sony music centre via SCART to output the TV audio through the Sony surround sound speaker system. I installed the new Viera TV in the same way.

I have hearing problems and need to use headphones whilst my wife listens to the TV sound at a lower volume from the audio set up. With my previous TV this worked perfectly but with the new TV there was a lag between the Headphones and TV speakers so that I could hear the headphones (and more quietly) the TV audio speakers out of sync. It is as if there was a timing difference between the TV speaker output and the headphone output from the TV. The difference was slight, but off-putting, and I am not sure which sound track lagged behind the other. The problem existed when I used the just in-built TV speakers – and when I connect the Theatre Audio system. I normally use wireless headphones but I tried wired ones and it was the same problem.

I tried various ideas suggested by the retailer without success and assumed that the Sony system was the culprit. Hence I purchased today a Panasonic Home Theatre Audio System model SC-HTB20 which is connected to HDMI 2 on the TV (Viera Link) and the headphones are plugged into the TV headphone jack.

I am disappointed to discover that the problem remains and I am mystified why the old Toshiba TV worked fine and the new Viera does not.

Is there anything that I can do to eliminate the “echo” heard in the headphones?

[Gandalph]

Not a lot of help at this point are they.

Hopefully they will try and reproduce the problem then find a solution. They may even send out an engineer from a local depot or department store to try and help. Fingers crossed they will come up with something.

[AlanHo]

The final message from Panasonic - brilliant aint it?

Dear Mr. Hopkinson,

Thank you for your e-mail.

Our escalations team have come back to me to advise the following-

I am afraid that there is no update for this, what is more than likely causing this is the TV processing the audio and the video which is then causing a slight audio delay. There are no updates, if the customer is unhappy with the TV they will have to talk to there retailer to see about an exchange or refund.

I trust that this information is of assistance to you. Should you have any further enquiries, please do not hesitate to contact our Technical Department via email, or alternatively on 0844 844 3899 between 9am and 5pm, Monday to Friday. Please quote your customer reference number: 447713

Kind Regards,

Ray L

Customer Service Team

Panasonic UK

[MANEMAN]

About what you would expect. :(

"We see this as purely a retail customer fault, as you should have taken headphones with you when you made the purchase. - Sort it out yourself."

I do like the line: "Our escalations team have come back to me to advise the following"

I can see me trying to fit that one in on some of the posters. :lol:

[Gandalph]

Great. No resolve there then.

I would have a word with the store where you bought the Television and see if you can get it changed. Take your headset along with you and give a few a try before you buy.