On Sun, 31 Oct 2021 03:21:22 -0700 (PDT), Phil Allison
<pallison49@gmail.com> wrote:

>Don Pearce wrote:
>===============
>>
>> >>>
>> >>> **DC coupled of course. Capacitors are so 1950.
>> >>
>> >> ** Are there any low frequency roll offs in the power amp ?
>> >
>> >**Nope. Frequency response is DC to 150kHz @ -2dB.
>> >
>> >> Or do subsonic inputs go right through to the speaker ?
>> >
>> >**Yep. Until the subsonic protection system is triggered. With the
>> >advent of CD players and other digital sources, subsonics are rarely a
>> >problem anymore. There is a coupling capacitor from the phono section in
>> >the preamp. Line inputs are all DC coupled.
>>
>>
>** So Don puked:
>>
>> As long as the phono section is capacitively coupled you're fine.
>
>** Oh really ??
>
>> You can get speaker-destroying signals at 5-10Hz from a cartridge
>> depending on the quality of arm damping.
>>
>
>** How exactly is that then ??
>
>When ( not if ) a tone arm is dropped onto an LP at volume - what stops a massive subsonic ?
>
>Do no aux input items *ever* make one of them either ?
>
>Many CD players are speced at being -0.5 dB at 5Hz.
>
>Might be an issue ?
>
>
>
>...... Phil
>
>
>
Having trouble there? Records are not flat and the ripples create
massive subsonic signals. If they happen to occur at the arm's
resonance they will be worse. The preamp has to work quite hard in
cutting out this stuff and a capacitive input on the phono connection
is a belt and braces approach that drops these signals even further.

But CD players specced at 0.5db at 5Hz? Why would that be a problem?
Ripply CDs don't generate LF signals.

d

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On Monday, November 1, 2021 at 12:04:44 AM UTC+11, Don Pearce wrote:
> On Sun, 31 Oct 2021 03:21:22 -0700 (PDT), Phil Allison
> <palli...@gmail.com> wrote:
>
> >Don Pearce wrote:
> >===============
> >>
> >> >>>
> >> >>> **DC coupled of course. Capacitors are so 1950.
> >> >>
> >> >> ** Are there any low frequency roll offs in the power amp ?
> >> >
> >> >**Nope. Frequency response is DC to 150kHz @ -2dB.
> >> >
> >> >> Or do subsonic inputs go right through to the speaker ?
> >> >
> >> >**Yep. Until the subsonic protection system is triggered. With the
> >> >advent of CD players and other digital sources, subsonics are rarely a
> >> >problem anymore. There is a coupling capacitor from the phono section in
> >> >the preamp. Line inputs are all DC coupled.
> >>
> >>
> >** So Don puked:
> >>
> >> As long as the phono section is capacitively coupled you're fine.
> >
> >** Oh really ??
> >
> >> You can get speaker-destroying signals at 5-10Hz from a cartridge
> >> depending on the quality of arm damping.
> >>
> >
> >** How exactly is that then ??
> >
> >When ( not if ) a tone arm is dropped onto an LP at volume - what stops a massive subsonic ?
> >
> >Do no aux input items *ever* make one of them either ?
> >
> >Many CD players are speced at being -0.5 dB at 5Hz.
> >
> >Might be an issue ?
> >
> >
> >
> Having trouble there? Records are not flat and the ripples create
> massive subsonic signals.

** Where exactly ??
Not at an amp's output.
Saying "speaker destroying" is a massive over claim.

> But CD players specced at 0.5db at 5Hz? Why would that be a problem?

** So nearly 2V rms at 5Hz on an aux input is a non issue ??

Sub-sonics exist in real sounds and condenser mics reproduce them as output signals.

When ( not if ) a tone arm is dropped onto an LP at volume - what stops a massive subsonic ?
Do no aux input items *ever* make one of them either ?

...... Phil

On Sun, 31 Oct 2021 14:40:41 -0700 (PDT), Phil Allison
<pallison49@gmail.com> wrote:

> Having trouble there? Records are not flat and the ripples create
>> massive subsonic signals.
>
>** Where exactly ??
> Not at an amp's output.
> Saying "speaker destroying" is a massive over claim.
>
It's called hyperbole.
>
>> But CD players specced at 0.5db at 5Hz? Why would that be a problem?
>
>** So nearly 2V rms at 5Hz on an aux input is a non issue ??
>
> Sub-sonics exist in real sounds and condenser mics reproduce them as output signals.
>
>When ( not if ) a tone arm is dropped onto an LP at volume - what stops a massive subsonic ?
>
>Do no aux input items *ever* make one of them either ?
>
>
>..... Phil

What is going to produce 2V at 5Hz? Mastering gets rid of all that
stuff and CDs don't have a mechanism to generate it unasked.
And dropped tone arms are exactly the sort of stuff you want to
minimize - hence AC coupling at several points along the signal chain.
Putting a specific capacitor on a phono input is a good way to help
mitigate stuff like that, whatever unknown deck is plugged in.

d

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Don Pearce wrote:
============
>
> >** Where exactly ??
> > Not at an amp's output.
> > Saying "speaker destroying" is a massive over claim.
> >
> It's called hyperbole.

** More correctly know as pommy BULLSHIT !

> >> But CD players specced at 0.5db at 5Hz? Why would that be a problem?
> >
> >** So nearly 2V rms at 5Hz on an aux input is a non issue ??
> >
> > Sub-sonics exist in real sounds and condenser mics reproduce them as output signals.
> >
> >When ( not if ) a tone arm is dropped onto an LP at volume - what stops a massive subsonic ?
> >
> >Do no aux input items *ever* make one of them either ?
> >
> >
> What is going to produce 2V at 5Hz?

** The CD player - cos nothing stops it.

> And dropped tone arms are exactly the sort of stuff you want to
> minimize - hence AC coupling at several points along the signal chain.

** So you say now - but previously you falsely claimed:

" As long as the phono section is capacitively coupled you're fine. You
can get speaker-destroying signals at 5-10Hz from a cartridge
depending on the quality of arm damping. "

> Putting a specific capacitor on a phono input is a good way to help
> mitigate stuff like that, whatever unknown deck is plugged in.

** It isn't a "good way" or even an effective one.

...... Phil

In article <iu6n5eFp4btU1@mid.individual.net>,
Trevor Wilson <trevor@rageaudio.com.au> wrote:
> On 31/10/2021 10:36 am, Phil Allison wrote:
> > Trevor Wilson wrote:
> > =================
> >>>
> >>> May I ask, is this pre-amp coupled to the power amp via a capacitor
> >>> or is it DC coupled?
> >>>
> >>> Bob.
> >>>
> >>
> >> **DC coupled of course. Capacitors are so 1950.
> >>
> >
> > ** Are there any low frequency roll offs in the power amp ?

> **Nope. Frequency response is DC to 150kHz @ -2dB.

> > Or do subsonic inputs go right through to the speaker ?

> **Yep. Until the subsonic protection system is triggered. With the
> advent of CD players and other digital sources, subsonics are
> rarely a problem anymore. There is a coupling capacitor from the
> phono section in the preamp. Line inputs are all DC coupled.

I've only seen this on one DVD ever but it can be reproduced with
ease..

The DVD is Master and Commander a film with Russell Crowe. there is a
scene in the film where there is a considerable DC offset on the 5.1
sound track. The offset is sufficient to trip the protection on an
Arcam P7 power-amp every time at normal volume.

At the time (2004) I wrote to Arcam and some of their reply here...

"Hi,
I have checked the Master and Comander DVD here it has a period of
about 400mS arround 12:40s that has a significant DC bias. About 0.5V
on the preamp outputs (ie. a significant part of the available
range has been taken up by DC as the outputs are 2V rms)"

Cheers,

Bob.

On Mon, 01 Nov 2021 09:23:41 +0000 (GMT), Bob Latham
<bob@sick-of-spam.invalid> wrote:

>In article <iu6n5eFp4btU1@mid.individual.net>,
> Trevor Wilson <trevor@rageaudio.com.au> wrote:
>> On 31/10/2021 10:36 am, Phil Allison wrote:
>> > Trevor Wilson wrote:
>> > =================
>> >>>
>> >>> May I ask, is this pre-amp coupled to the power amp via a capacitor
>> >>> or is it DC coupled?
>> >>>
>> >>> Bob.
>> >>>
>> >>
>> >> **DC coupled of course. Capacitors are so 1950.
>> >>
>> >
>> > ** Are there any low frequency roll offs in the power amp ?
>
>> **Nope. Frequency response is DC to 150kHz @ -2dB.
>
>> > Or do subsonic inputs go right through to the speaker ?
>
>> **Yep. Until the subsonic protection system is triggered. With the
>> advent of CD players and other digital sources, subsonics are
>> rarely a problem anymore. There is a coupling capacitor from the
>> phono section in the preamp. Line inputs are all DC coupled.
>
>I've only seen this on one DVD ever but it can be reproduced with
>ease..
>
>The DVD is Master and Commander a film with Russell Crowe. there is a
>scene in the film where there is a considerable DC offset on the 5.1
>sound track. The offset is sufficient to trip the protection on an
>Arcam P7 power-amp every time at normal volume.
>
>At the time (2004) I wrote to Arcam and some of their reply here...
>
>"Hi,
>
>I have checked the Master and Comander DVD here it has a period of
>about 400mS arround 12:40s that has a significant DC bias. About 0.5V
>on the preamp outputs (ie. a significant part of the available
>range has been taken up by DC as the outputs are 2V rms)"
>
>Cheers,
>
>Bob.

Then perhaps the line inputs should have a coupling cap too.

d

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Bob Latham
==========
>
> >I have checked the Master and Comander DVD here it has a period of
> >about 400mS arround 12:40s that has a significant DC bias. About 0.5V
> >on the preamp outputs (ie. a significant part of the available
> >range has been taken up by DC as the outputs are 2V rms)"
>>

** Wow - so your Arcam P7 is DC coupled from in to out ?

Bet large & deep subsonics are common on DVDs.

........ Phil

On Mon, 01 Nov 2021 09:45:28 GMT, spam@spam.com (Don Pearce) wrote:

>>I have checked the Master and Comander DVD here it has a period of
>>about 400mS arround 12:40s that has a significant DC bias. About 0.5V
>>on the preamp outputs (ie. a significant part of the available
>>range has been taken up by DC as the outputs are 2V rms)"
>>
>>Cheers,
>>
>>Bob.
>
>Then perhaps the line inputs should have a coupling cap too.
>
>d

I should add that coupling caps can actually make the problem worse.
If you start with a 1V pk-pk square wave and put it through a coupling
cap that is a bit too small, what comes out is a 2V pk-pk spiky wave.
Sure the power is less, but power amps are voltage sources - they
don't run in a matched condition. So a high-passed square wave may
well push an amp into clipping.

d

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In article <86dc1b98-71d6-4de6-a51e-e1ccf5949f87n@googlegroups.com>,
Phil Allison <pallison49@gmail.com> wrote

> > >I have checked the Master and Comander DVD here it has a period
> > >of about 400mS arround 12:40s that has a significant DC bias.
> > >About 0.5V on the preamp outputs (ie. a significant part of the
> > >available range has been taken up by DC as the outputs are 2V
> > >rms)"

> ** Wow - so your Arcam P7 is DC coupled from in to out ?

Indeed, yes it is.

> Bet large & deep subsonics are common on DVDs.

That maybe so but I've only experienced one disc that gave a
noticeable issue.

Bob.

On 1/11/2021 8:23 pm, Bob Latham wrote:
> In article <iu6n5eFp4btU1@mid.individual.net>,
> Trevor Wilson <trevor@rageaudio.com.au> wrote:
>> On 31/10/2021 10:36 am, Phil Allison wrote:
>>> Trevor Wilson wrote:
>>> =================
>>>>>
>>>>> May I ask, is this pre-amp coupled to the power amp via a capacitor
>>>>> or is it DC coupled?
>>>>>
>>>>> Bob.
>>>>>
>>>>
>>>> **DC coupled of course. Capacitors are so 1950.
>>>>
>>>
>>> ** Are there any low frequency roll offs in the power amp ?
>
>> **Nope. Frequency response is DC to 150kHz @ -2dB.
>
>>> Or do subsonic inputs go right through to the speaker ?
>
>> **Yep. Until the subsonic protection system is triggered. With the
>> advent of CD players and other digital sources, subsonics are
>> rarely a problem anymore. There is a coupling capacitor from the
>> phono section in the preamp. Line inputs are all DC coupled.
>
> I've only seen this on one DVD ever but it can be reproduced with
> ease..
>
> The DVD is Master and Commander a film with Russell Crowe. there is a
> scene in the film where there is a considerable DC offset on the 5.1
> sound track. The offset is sufficient to trip the protection on an
> Arcam P7 power-amp every time at normal volume.
>
> At the time (2004) I wrote to Arcam and some of their reply here...
>
> "Hi,
>
> I have checked the Master and Comander DVD here it has a period of
> about 400mS arround 12:40s that has a significant DC bias. About 0.5V
> on the preamp outputs (ie. a significant part of the available
> range has been taken up by DC as the outputs are 2V rms)"
>
> Cheers,
>
> Bob.
>

**I'll take your word for it. I have a few (3) stereo systems. No home
cinema systems.

Phil Allison wrote:
============
> Bob Latham
> ==========
> >
> > >I have checked the Master and Comander DVD here it has a period of
> > >about 400mS arround 12:40s that has a significant DC bias. About 0.5V
> > >on the preamp outputs (ie. a significant part of the available
> > >range has been taken up by DC as the outputs are 2V rms)"
>

** This claim is highly dubious.

I have a copy of that DVD and checked it between 12.00 and 13.30.
With a DMM connected to L & R output on my Sony DVD player, there is no such offset.

The 12:40 time corresponds with some fairly loud drumming ( a beat to arms).

" Smoke and Hocum. "

....... phil

In article <7c8ad072-1501-4ff2-970f-d50785dc71ebn@googlegroups.com>,
Phil Allison <pallison49@gmail.com> wrote:
> Phil Allison wrote:
> ============
> > Bob Latham
> > ==========
> > >
> > > >I have checked the Master and Comander DVD here it has a
> > > >period of about 400mS arround 12:40s that has a significant
> > > >DC bias. About 0.5V on the preamp outputs (ie. a significant
> > > >part of the available range has been taken up by DC as the
> > > >outputs are 2V rms)"
> >

> ** This claim is highly dubious.

> I have a copy of that DVD and checked it between 12.00 and 13.30.
> With a DMM connected to L & R output on my Sony DVD player, there
> is no such offset.

> The 12:40 time corresponds with some fairly loud drumming ( a beat
> to arms).

> " Smoke and Hocum. "

> ...... phil

Believe what you want.

Bob.

On Mon, 01 Nov 2021 09:23:41 +0000 (GMT), Bob Latham
<bob@sick-of-spam.invalid> wrote:

>
>I have checked the Master and Comander DVD here it has a period of
>about 400mS arround 12:40s that has a significant DC bias. About 0.5V
>on the preamp outputs (ie. a significant part of the available
>range has been taken up by DC as the outputs are 2V rms)"
>
>Cheers,

I've done an FFT and I can't see it. This plot shows it lowpass
filtered at 50Hz. Plenty of material for the LFE speaker, but no DC
offset. You should see the line lifting to about -12 if there was.

http://soundthoughts.co.uk/look/mc.png

d

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In article <6181a6fc.45087796@news.eternal-september.org>,
Don Pearce <spam@spam.com> wrote:
> On Mon, 01 Nov 2021 09:23:41 +0000 (GMT), Bob Latham
> <bob@sick-of-spam.invalid> wrote:

> >
> >I have checked the Master and Comander DVD here it has a period of
> >about 400mS arround 12:40s that has a significant DC bias. About 0.5V
> >on the preamp outputs (ie. a significant part of the available
> >range has been taken up by DC as the outputs are 2V rms)"
> >
> >Cheers,

> I've done an FFT and I can't see it. This plot shows it lowpass
> filtered at 50Hz. Plenty of material for the LFE speaker, but no DC
> offset. You should see the line lifting to about -12 if there was.

> http://soundthoughts.co.uk/look/mc.png

OK fine but I'm not lying, why on earth would I?

I don't see why Arcam should lie either. Their comments came from
Andy Dutton, Senior Engineer 26-04-2004.

More likely the problem was pointed out to the disc manufacturer and
they changed it for future production.

I wasn't the only one with the issue either, there was a whole thread
about it on AV forums at the time.

Andy went on to say...

As has been mentioned here before both the AV8 and P7 are DC coupled
with servos to remove any DC offset. This is to preserve the bass
timing and improve sound quality by removing electrolicitc capacitors
from the signal path.
For this to work we rely on CD and DVD manufactures not to record DC
on their disks. It has no benifit as you cannot hear it all it does
is make the drive units cones flap about, so there is no reason to
record it on the disk.
We cannot change the DC detector time in the P7 as it is a hardware
feature and to AC couple the AV8 all the time would compromise the
sound quality.
However you can solve this problem by creating a preset
configuration using the THX or THX EX settings in Speaker Sizes menu.
This will create a speaker setup using all small and direct all of
the base to the subwoofer (or you can manualy set all speakers to
small with sub present if you prefer) . This effectively AC couples
the AV8 in the digital domain and your subwoofer will almost
certainly be AC coupled so will not have the same problem.
This preset can then be used whenever you have a disk that has been
incorrectly recorded with DC on it. I would recomend using your
standard configuration for other disks (unless you have a THX type
sub sat set up in which case you should not have seen this problem
anyway) as you will get better sound quality.

Cheers,

Bob.

On Wed, 03 Nov 2021 08:57:33 +0000 (GMT), Bob Latham
<bob@sick-of-spam.invalid> wrote:

>OK fine but I'm not lying, why on earth would I?

I wasn't imagining for one moment that you were lying. I'm well aware
that many differing versions of soundtracks get released, and probably
a new mastering engineer gets involved at every print run. If you
want, you can extract the offending bit of yours in WAV or FLAC format
and I can take a look at it. I'd be interested to see the difference.

d

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Bob Latham
==========
>
> >OK fine but I'm not lying, why on earth would I?
>

** Explain how you did your tests.
What instruments were used ?

Why use your pre- amp out as a test point ?
How did you arrive at 400mS ?
How did you get 0.5V DC ?

Other "scientists " need to be able to repeat your experiment .
Remember " Cold Fusion " ???

....... Phil

In article <617fccfb.6747578@news.eternal-september.org>, Don Pearce
<spam@spam.com> wrote:

> I should add that coupling caps can actually make the problem worse. If
> you start with a 1V pk-pk square wave and put it through a coupling cap
> that is a bit too small, what comes out is a 2V pk-pk spiky wave. Sure
> the power is less, but power amps are voltage sources - they don't run
> in a matched condition. So a high-passed square wave may well push an
> amp into clipping.

A square wave will be more audibly loud, though, so help alert the listener
to the idiotic source content.

I've always used dc break caps. But when you aim at a flat response that is
only 0.2dB down at 20Hz, and want to avoid excess dispersion, daft LF input
signals may still get though.

Jim

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In article <59847afd3ebob@sick-of-spam.invalid>, Bob Latham
<bob@sick-of-spam.invalid> wrote:
> I've only seen this on one DVD ever but it can be reproduced with ease..

> The DVD is Master and Commander a film with Russell Crowe. there is a
> scene in the film where there is a considerable DC offset on the 5.1
> sound track. The offset is sufficient to trip the protection on an Arcam
> P7 power-amp every time at normal volume.

> At the time (2004) I wrote to Arcam and some of their reply here...

> "Hi,
>
> I have checked the Master and Comander DVD here it has a period of about
> 400mS arround 12:40s that has a significant DC bias. About 0.5V on the
> preamp outputs (ie. a significant part of the available range has been
> taken up by DC as the outputs are 2V rms)"

Wow! (Pun intended!) That's an insane thing to put on a DVD.Is it
deliberate, or down to carelessness? i.e. are they going for 'Earthquake'
special effects or just being stupid?

Given some of the idiotic 'mastering' I've observed on CDs, maybe we
shouldn't be surprised that equivalent idiocy pops up on some DVDs. But you
kinda hope the makers had more sense.

Jim

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In article <iuaudpFjf7hU1@mid.individual.net>, Trevor Wilson
<trevor@rageaudio.com.au> wrote:

> **I'll take your word for it. I have a few (3) stereo systems. No home
> cinema systems.

FWIW we simply use a stereo setup connected to the TV. Stereo, so choose
the stereo or stereo-mixdown by default. Not noticed encountering anything
like Bob has, so far as I know.

Jim

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In article <7c8ad072-1501-4ff2-970f-d50785dc71ebn@googlegroups.com>, Phil
Allison <pallison49@gmail.com> wrote:
> Phil Allison wrote: ============
> > Bob Latham ==========
> > >
> > > >I have checked the Master and Comander DVD here it has a period of
> > > >about 400mS arround 12:40s that has a significant DC bias. About
> > > >0.5V on the preamp outputs (ie. a significant part of the
> > > >available range has been taken up by DC as the outputs are 2V
> > > >rms)"
> >

> ** This claim is highly dubious.

> I have a copy of that DVD and checked it between 12.00 and 13.30. With
> a DMM connected to L & R output on my Sony DVD player, there is no such
> offset.

> The 12:40 time corresponds with some fairly loud drumming ( a beat to
> arms).

> " Smoke and Hocum. "

What sound formats/tracks does the disc have?

Jim

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In article <61824ff0.3103203@news.eternal-september.org>,
Don Pearce <spam@spam.com> wrote:
> On Wed, 03 Nov 2021 08:57:33 +0000 (GMT), Bob Latham
> <bob@sick-of-spam.invalid> wrote:

> >OK fine but I'm not lying, why on earth would I?

> I wasn't imagining for one moment that you were lying.

Thanks.

> I'm well aware that many differing versions of soundtracks get
> released, and probably a new mastering engineer gets involved at
> every print run. If you want, you can extract the offending bit of
> yours in WAV or FLAC format and I can take a look at it. I'd be
> interested to see the difference.

Thanks for that Don.

Actually, I had a quick look for the disc this morning and didn't
find it. That doesn't mean I don't have it anymore it may just be in
the loft but it is possible SWMBO has taken it to a charity shop.

I'll have a better look later.

Cheers,

Bob.

In article <5ec0881f-0976-4382-97de-6b28bc034498n@googlegroups.com>,
Phil Allison <pallison49@gmail.com> wrote:
> Bob Latham
> ==========
> >
> > >OK fine but I'm not lying, why on earth would I?
> >

> ** Explain how you did your tests.
> What instruments were used ?

I didn't do any tests as such nor did I claim that I did. I played
the disc and it tripped the protection. I played the disc again, it
tripped again. End of tests.

> Why use your pre- amp out as a test point ?
> How did you arrive at 400mS ?
> How did you get 0.5V DC ?

None of that came from me! As I wrote - It came from Andy Dutton at
Arcam.

> Other "scientists " need to be able to repeat your experiment .
> Remember " Cold Fusion " ???

I did repeat my bit.

Actually, (I've not looked) but this *may* all be in the Arcam
section of AV forums from the time, I'll look later.

Bob.

In article <5985008df2noise@audiomisc.co.uk>,
Jim Lesurf <noise@audiomisc.co.uk> wrote:
> In article <7c8ad072-1501-4ff2-970f-d50785dc71ebn@googlegroups.com>, Phil
> Allison <pallison49@gmail.com> wrote:
> > Phil Allison wrote: ============
> > > Bob Latham ==========
> > > >
> > > > >I have checked the Master and Comander DVD here it has a period of
> > > > >about 400mS arround 12:40s that has a significant DC bias. About
> > > > >0.5V on the preamp outputs (ie. a significant part of the
> > > > >available range has been taken up by DC as the outputs are 2V
> > > > >rms)"
> > >

> > ** This claim is highly dubious.

> > I have a copy of that DVD and checked it between 12.00 and 13.30.
> > With a DMM connected to L & R output on my Sony DVD player, there
> > is no such offset.

> > The 12:40 time corresponds with some fairly loud drumming ( a
> > beat to arms).

> > " Smoke and Hocum. "

> What sound formats/tracks does the disc have?

Not seen the disc for some time and couldn't find it this morning.
I'll have another look later. It would have been a 5.1 output I'm
sure, either dolby or DTS. I will try to confirm later.

Bob.

In article <59858ba18dbob@sick-of-spam.invalid>,
Bob Latham <bob@sick-of-spam.invalid> wrote:
> In article <5985008df2noise@audiomisc.co.uk>,
> Jim Lesurf <noise@audiomisc.co.uk> wrote:

> > What sound formats/tracks does the disc have?

> Not seen the disc for some time and couldn't find it this morning.
> I'll have another look later. It would have been a 5.1 output I'm
> sure, either dolby or DTS. I will try to confirm later.

Much to my surprise I've found it !!

It was 5.1 DTS

Bob.

In article <598589798dbob@sick-of-spam.invalid>,
Bob Latham <bob@sick-of-spam.invalid> wrote:
> In article <61824ff0.3103203@news.eternal-september.org>,
> Don Pearce <spam@spam.com> wrote:
> > On Wed, 03 Nov 2021 08:57:33 +0000 (GMT), Bob Latham
> > <bob@sick-of-spam.invalid> wrote:

> > >OK fine but I'm not lying, why on earth would I?

> > I wasn't imagining for one moment that you were lying.

> Thanks.

> > I'm well aware that many differing versions of soundtracks get
> > released, and probably a new mastering engineer gets involved at
> > every print run. If you want, you can extract the offending bit of
> > yours in WAV or FLAC format and I can take a look at it. I'd be
> > interested to see the difference.

> Thanks for that Don.

> Actually, I had a quick look for the disc this morning and didn't
> find it. That doesn't mean I don't have it anymore it may just be in
> the loft but it is possible SWMBO has taken it to a charity shop.

> I'll have a better look later.

I've found it !

5.1 DTS.

If it was a stereo CD extracting to flac or WAV 99.99% of the time
really easy. But extracting 5.1 DTS from a DVD, how would I do that?

Bob.