AKG C451 mics
 

Is anyone here still using AKG C451 mics, or remembers using them?

I've had my 4 for some time but am becoming more and more aware of a low
level hum on the output. The hum gets worse the more of them that are
plugged in to the mixer. If only one is faded up, the hum gets worse as
others are plugged in. At first I thought the phantom power supply was
giving trouble but I have now tried them on two different mixers and a,
stereo, standalone mic pre-amp (M-Audio) with similar results. I wondered
if one of them was drawing too much current and dragging the PS down but it
doesn't seem to matter which combination of mics I use. I think the hum is
100 hertz, which still suggests PS but on three differant i/ps?

Both mixers and the standalone are fine when used with dynamic mics.

The C451s are long in the tooth so are they prone to draw high current as
they age? Or am I barking up the wrong tree altogether?

Any suggestions, polite ones, would be appreciated.

Thanks.

Alan S.

AKG C451 mics
 

Does the buzz happen in any location, or just in one. I was thinking some
kind of inductive or rf pick up in the particular location, after all, not
much to go wrong in this way is there?
Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:
__________________________________________________ __________________________________________________ __________


"Alan S." wrote in message
.145...
Is anyone here still using AKG C451 mics, or remembers using them?

I've had my 4 for some time but am becoming more and more aware of a low
level hum on the output. The hum gets worse the more of them that are
plugged in to the mixer. If only one is faded up, the hum gets worse as
others are plugged in. At first I thought the phantom power supply was
giving trouble but I have now tried them on two different mixers and a,
stereo, standalone mic pre-amp (M-Audio) with similar results. I wondered
if one of them was drawing too much current and dragging the PS down but
it
doesn't seem to matter which combination of mics I use. I think the hum is
100 hertz, which still suggests PS but on three differant i/ps?

Both mixers and the standalone are fine when used with dynamic mics.

The C451s are long in the tooth so are they prone to draw high current as
they age? Or am I barking up the wrong tree altogether?

Any suggestions, polite ones, would be appreciated.

Thanks.

Alan S.

AKG C451 mics
 

"Alan S."

Is anyone here still using AKG C451 mics, or remembers using them?


** The C451 is not a mic - but a pre-amp / handle for the CK series of
capsules.


I've had my 4 for some time but am becoming more and more aware of a low
level hum on the output. The hum gets worse the more of them that are
plugged in to the mixer. If only one is faded up, the hum gets worse as
others are plugged in.

** That can only mean the phantom power has hum.


At first I thought the phantom power supply was
giving trouble but I have now tried them on two different mixers and a,
stereo, standalone mic pre-amp (M-Audio) with similar results. I wondered
if one of them was drawing too much current and dragging the PS down but
it
doesn't seem to matter which combination of mics I use. I think the hum is
100 hertz, which still suggests PS but on three differant i/ps?

** Your story indicates that it is all 3.


Both mixers and the standalone are fine when used with dynamic mics.


** Naturally.


The C451s are long in the tooth so are they prone to draw high current as
they age?

** C451s draw about 6mA from a 48 volt phantom supply - many other mics
draw less than this.

The design is such that they work fine from as little as 9 volts of phantom
at the mic signal pins, with a much lower current draw than when that
voltage is 48.

From recollection, C451s are not particularly immune from hum on the phantom
supply ( there should NOT be any of course ) so your probelm as decribed is
not likely due to any fault in the mics.


...... Phil

AKG C451 mics
 

"Brian Gaff" wrote in
m:

Does the buzz happen in any location, or just in one. I was thinking
some kind of inductive or rf pick up in the particular location, after
all, not much to go wrong in this way is there?
Brian


It has been apparent at two different locations in particular, both of them
CofE churches as it happens. It was, however, with the same mic cables. Can
I assume that the phantom power supply would not work if one leg or ground
is missing on the cable? They were each approximately 25metres.

Thanks for your thought, but to be pedantic, it is a hum, not a buzz. If it
was a buzz I'd be looking for things like lighting dimmer buzz etc.

Thanks again.

Alan S.

AKG C451 mics
 

"Phil Allison" wrote in
:


"Alan S."

Is anyone here still using AKG C451 mics, or remembers using them?


** The C451 is not a mic - but a pre-amp / handle for the CK series
of capsules.

I think most epeople referred to them as C451 mics but for the record,
it was C451 bodies with CK1 capsules.



I've had my 4 for some time but am becoming more and more aware of a
low level hum on the output. The hum gets worse the more of them that
are plugged in to the mixer. If only one is faded up, the hum gets
worse as others are plugged in.

** That can only mean the phantom power has hum.


At first I thought the phantom power supply was
giving trouble but I have now tried them on two different mixers and
a, stereo, standalone mic pre-amp (M-Audio) with similar results. I
wondered if one of them was drawing too much current and dragging the
PS down but it
doesn't seem to matter which combination of mics I use. I think the
hum is 100 hertz, which still suggests PS but on three differant
i/ps?

** Your story indicates that it is all 3.

My first reaction but I couldn't couldn't believe 3 different PSs were
_faulty_.


Both mixers and the standalone are fine when used with dynamic mics.


** Naturally.


The C451s are long in the tooth so are they prone to draw high
current as they age?

** C451s draw about 6mA from a 48 volt phantom supply - many other
mics draw less than this.

The design is such that they work fine from as little as 9 volts of
phantom at the mic signal pins, with a much lower current draw than
when that voltage is 48.

From recollection, C451s are not particularly immune from hum on the
phantom supply ( there should NOT be any of course ) so your probelm
as decribed is not likely due to any fault in the mics.


..... Phil





If I have three phantom supplies which are unable to deliver the
required current, which appears to be the case, then, I need to use an
outside supply. I've been out of the scene for a few years so which are
good units these days?

Thanks for your input, Phil.

Alan S.

AKG C451 mics
 

In article ,
Alan S. wrote:
Is anyone here still using AKG C451 mics, or remembers using them?

Hi Alan ;-) Yes indeedy - I also have a few.


I've had my 4 for some time but am becoming more and more aware of a low
level hum on the output. The hum gets worse the more of them that are
plugged in to the mixer. If only one is faded up, the hum gets worse as
others are plugged in. At first I thought the phantom power supply was
giving trouble but I have now tried them on two different mixers and a,
stereo, standalone mic pre-amp (M-Audio) with similar results. I
wondered if one of them was drawing too much current and dragging the
PS down but it doesn't seem to matter which combination of mics I use.

Properly designed phantom should be immune to a dead short since standoff
resistors are used at each mic input. That's not to say all mixers have
properly designed phantom.


I think the hum is
100 hertz, which still suggests PS but on three differant i/ps?

Both mixers and the standalone are fine when used with dynamic mics.

The C451s are long in the tooth so are they prone to draw high current
as they age? Or am I barking up the wrong tree altogether?

Not one I've come across.

Any suggestions, polite ones, would be appreciated.

It does sound like a PS fault to me - have you tried other phantom powered
mics? Have you access to a scope to look at the DC?

--
*Never underestimate the power of very stupid people in large groups *

Dave Plowman London SW
To e-mail, change noise into sound.

AKG C451 mics
 

"Alan S." wrote in message
.145...
"Brian Gaff" wrote in
m:

Does the buzz happen in any location, or just in one. I was thinking
some kind of inductive or rf pick up in the particular location, after
all, not much to go wrong in this way is there?
Brian


It has been apparent at two different locations in particular, both of
them
CofE churches as it happens. It was, however, with the same mic cables.

Then I think the cables might well need looking at.

Can
I assume that the phantom power supply would not work if one leg or ground
is missing on the cable? They were each approximately 25metres.

If ground is missing the phantom power will not work. It will work if one
leg is missing, but you will get poor audio and added noise.


David.

AKG C451 mics
 

In article ,
Alan S. wrote:
It has been apparent at two different locations in particular, both of
them CofE churches as it happens. It was, however, with the same mic
cables. Can I assume that the phantom power supply would not work if
one leg or ground is missing on the cable? They were each approximately
25metres.

Seem to remember a one legged cable just results in a low output from a
451. Which may well give hum if you increase the gain for a distant mic.
Do you not have a 'bright eyes' phantom tester? Basically two leds built
into an XLR. If not contact me - I'm sure I've got a spare.

If you lose the screen you'll get no audio at all, IIRC.

--
*42.7% of statistics are made up. Sorry, that should read 47.2% *

Dave Plowman London SW
To e-mail, change noise into sound.

AKG C451 mics
 

"David Looser" wrote in
:

"Alan S." wrote in message
.145...
"Brian Gaff" wrote in
m:

Does the buzz happen in any location, or just in one. I was thinking
some kind of inductive or rf pick up in the particular location,
after all, not much to go wrong in this way is there?
Brian


It has been apparent at two different locations in particular, both
of them
CofE churches as it happens. It was, however, with the same mic
cables.

Then I think the cables might well need looking at.

Yes, it's looking that way. I'll bet there's a rogue somewhere! Now
where's my bright-eyes?



Can
I assume that the phantom power supply would not work if one leg or
ground is missing on the cable? They were each approximately
25metres.

If ground is missing the phantom power will not work. It will work if
one leg is missing, but you will get poor audio and added noise.


David.





Thanks again.

Alan S.

AKG C451 mics
 

"Dave Plowman (News)" wrote in message
...

Seem to remember a one legged cable just results in a low output from a
451. Which may well give hum if you increase the gain for a distant mic.


With a one-legged cable the audio must pass through the phantom power
supply, thus directly adding any hum or noise it creates to the audio. The
level will also be down.

If you lose the screen you'll get no audio at all, IIRC.

Because there will then be no phantom power at the microphone.

David.

AKG C451 mics
 

"Dave Plowman (News)" wrote in
:

In article ,
Alan S. wrote:
Is anyone here still using AKG C451 mics, or remembers using them?

Hi Alan ;-) Yes indeedy - I also have a few.

Hello Dave.


I've had my 4 for some time but am becoming more and more aware of a
low level hum on the output. The hum gets worse the more of them that
are plugged in to the mixer. If only one is faded up, the hum gets
worse as others are plugged in. At first I thought the phantom power
supply was giving trouble but I have now tried them on two different
mixers and a, stereo, standalone mic pre-amp (M-Audio) with similar
results. I wondered if one of them was drawing too much current and
dragging the PS down but it doesn't seem to matter which combination
of mics I use.

Properly designed phantom should be immune to a dead short since
standoff resistors are used at each mic input. That's not to say all
mixers have properly designed phantom.


I think the hum is
100 hertz, which still suggests PS but on three differant i/ps?

Both mixers and the standalone are fine when used with dynamic mics.

The C451s are long in the tooth so are they prone to draw high
current as they age? Or am I barking up the wrong tree altogether?

Not one I've come across.

Any suggestions, polite ones, would be appreciated.

It does sound like a PS fault to me - have you tried other phantom
powered mics? Have you access to a scope to look at the DC?


My Heathkit scope went the way of all flesh many moons ago! But my gut
instinct says PS. I just couldn't believe 2 mixers and one standalone
all had a problem. A careful cable check has been suggested, just in
case there's a rogue. Ah, memories of those aweful _tails_ on the booms
at TVC.

Alan S.

AKG C451 mics
 

"Dave Plowman (News)" wrote in
:

In article ,
Alan S. wrote:
It has been apparent at two different locations in particular, both
of them CofE churches as it happens. It was, however, with the same
mic cables. Can I assume that the phantom power supply would not work
if one leg or ground is missing on the cable? They were each
approximately 25metres.

Seem to remember a one legged cable just results in a low output from
a 451. Which may well give hum if you increase the gain for a distant
mic. Do you not have a 'bright eyes' phantom tester? Basically two
leds built into an XLR. If not contact me - I'm sure I've got a spare.

If you lose the screen you'll get no audio at all, IIRC.


Thanks for the offer, Dave. I have got one somewhere, buried in the goodie
box. It's a long time since I used it - more than eight years since
retiring from TVC and Parkinson's means my days carting gear around are
probably numbered!

Now, where's the goodie box?

Thanks to all for your thoughts.

Alan S.

AKG C451 mics
 

If you lose the screen you will probably get radio Moscow instead..grin.

Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Dave Plowman (News)" wrote in message
...
In article ,
Alan S. wrote:
It has been apparent at two different locations in particular, both of
them CofE churches as it happens. It was, however, with the same mic
cables. Can I assume that the phantom power supply would not work if
one leg or ground is missing on the cable? They were each approximately
25metres.

Seem to remember a one legged cable just results in a low output from a
451. Which may well give hum if you increase the gain for a distant mic.
Do you not have a 'bright eyes' phantom tester? Basically two leds built
into an XLR. If not contact me - I'm sure I've got a spare.

If you lose the screen you'll get no audio at all, IIRC.

--
*42.7% of statistics are made up. Sorry, that should read 47.2% *

Dave Plowman London SW
To e-mail, change noise into sound.

AKG C451 mics
 

On Sat, 30 May 2009 11:21:17 GMT, "Brian Gaff"
wrote:

If you lose the screen you will probably get radio Moscow instead..grin.

Brian

At least that might be interesting. It's always minicabs.

d

AKG C451 mics
 

In article ,
Brian Gaff wrote:
If you lose the screen you will probably get radio Moscow instead..grin.


You'd be surprised. Some time ago I made up 100v line XLR cables using
ordinary mains 2 core flex. Cheaper than screened cable. And found one in
use with a dynamic hand mic - because it was a nice shiny white, rather
than the more usual mic cable grey or black. And apparently worked just
fine. In other words it's the balancing that gives the majority of the
rejection of spurious stuff.

--
*Time is the best teacher; unfortunately it kills all its students.

Dave Plowman London SW
To e-mail, change noise into sound.

AKG C451 mics
 

"Alan S."

It has been apparent at two different locations in particular, both of
them
CofE churches as it happens. It was, however, with the same mic cables.
Can
I assume that the phantom power supply would not work if one leg or ground
is missing on the cable? They were each approximately 25metres.

** All 3 with the same fault??

Yawnnnnnnnnnnnnnnnnnnnnnn



..... Phil

AKG C451 mics
 

"David Loser"


With a one-legged cable the audio must pass through the phantom power
supply,


** The OP is a ****wit TROLL

you ass.

AKG C451 mics
 

"Alan S."

Is anyone here still using AKG C451 mics, or remembers using them?


** The C451 is not a mic - but a pre-amp / handle for the CK series
of capsules.

I think most epeople referred to them as C451 mics but for the record,
it was C451 bodies with CK1 capsules.

** CK1 = basic cardiod capsule.

Got a nice CK2 omni myself I use for response testing.



I've had my 4 for some time but am becoming more and more aware of a
low level hum on the output. The hum gets worse the more of them that
are plugged in to the mixer. If only one is faded up, the hum gets
worse as others are plugged in.

** That can only mean the phantom power has hum.


At first I thought the phantom power supply was
giving trouble but I have now tried them on two different mixers and
a, stereo, standalone mic pre-amp (M-Audio) with similar results. I
wondered if one of them was drawing too much current and dragging the
PS down but it
doesn't seem to matter which combination of mics I use. I think the
hum is 100 hertz, which still suggests PS but on three differant
i/ps?

** Your story indicates that it is all 3.

My first reaction but I couldn't couldn't believe 3 different PSs were
_faulty_.


Both mixers and the standalone are fine when used with dynamic mics.


** Naturally.


The C451s are long in the tooth so are they prone to draw high
current as they age?

** C451s draw about 6mA from a 48 volt phantom supply - many other
mics draw less than this.

The design is such that they work fine from as little as 9 volts of
phantom at the mic signal pins, with a much lower current draw than
when that voltage is 48.

From recollection, C451s are not particularly immune from hum on the
phantom supply ( there should NOT be any of course ) so your probelm
as decribed is not likely due to any fault in the mics.



If I have three phantom supplies which are unable to deliver the
required current, which appears to be the case, then,


** Nope.

The actual case is your story is 100% total ********.




......... Phil

AKG C451 mics
 

In article ,
Phil Allison wrote:
I think most epeople referred to them as C451 mics but for the record,
it was C451 bodies with CK1 capsules.

** CK1 = basic cardiod capsule.

By far and away the most common combination was a 451 with CK1 capsule -
in Alan's and my side of the industry anyway - so there was no need to
call it anything other than a 451. The handmic version was called a 421
omni. The gun mic varieties weren't used - the Sennheisers were so much
better.

Got a nice CK2 omni myself I use for response testing.

I've got a couple of what was known as the TV omni with a built in
windshield. IIRC, CK22. Quite a rarity.

--
*Why do we say something is out of whack? What is a whack? *

Dave Plowman London SW
To e-mail, change noise into sound.

AKG C451 mics
 

Phil Allison wrote:
"David Loser"


With a one-legged cable the audio must pass through the phantom power
supply,


** The OP is a ****wit TROLL

you ass.


That is strange...how did you manage to climb out of my killfile ????

Ahh well, not to worry......plonk !

AKG C451 mics
 

"Dave Plowman (News)"
Phil Allison

I think most epeople referred to them as C451 mics but for the record,
it was C451 bodies with CK1 capsules.

** CK1 = basic cardiod capsule.

By far and away the most common combination was a 451 with CK1 capsule -
in Alan's and my side of the industry anyway - so there was no need to
call it anything other than a 451.


** Local jargon.

The handmic version was called a 421 omni.


** Kindly post a link to one of them.

The hand held mic 451 capsule was the CK5 - essentially a CK1 capsule
fully sprung and wind shielded.



..... Phil

AKG C451 mics
 

In article ,
Phil Allison wrote:

"Dave Plowman (News)"
Phil Allison

I think most epeople referred to them as C451 mics but for the record,
it was C451 bodies with CK1 capsules.

** CK1 = basic cardiod capsule.

By far and away the most common combination was a 451 with CK1 capsule -
in Alan's and my side of the industry anyway - so there was no need to
call it anything other than a 451.


** Local jargon.

The handmic version was called a 421 omni.


** Kindly post a link to one of them.

Sorry, typo. Should have been 451 omni.

The hand held mic 451 capsule was the CK5 - essentially a CK1 capsule
fully sprung and wind shielded.

In TV at the time we normally used omnis as hand mics. Not the same sort
of levels of foldback you get these days. An omni is far better for hand
held use - less 'popping' and level changes if it's moved around.

Look for CK22 for that capsule. Built in windshield so small 'in shot'.

--
*You are validating my inherent mistrust of strangers

Dave Plowman London SW
To e-mail, change noise into sound.

AKG C451 mics
 

In article 4a2816f3.105242859@localhost, Don Pearce
scribeth thus
On Sat, 30 May 2009 11:21:17 GMT, "Brian Gaff"
wrote:

If you lose the screen you will probably get radio Moscow instead..grin.

Brian

At least that might be interesting. It's always minicabs.

d

When did you hear minicab radio breakthrough last?..

Seeing that AM has been out of fashion for some 20 years now?.

At least in the UK...

--
Tony Sayer

AKG C451 mics
 

In article , Dave Plowman (News)
scribeth thus
In article ,
Brian Gaff wrote:
If you lose the screen you will probably get radio Moscow instead..grin.


You'd be surprised. Some time ago I made up 100v line XLR cables using
ordinary mains 2 core flex. Cheaper than screened cable. And found one in
use with a dynamic hand mic - because it was a nice shiny white, rather
than the more usual mic cable grey or black. And apparently worked just
fine. In other words it's the balancing that gives the majority of the
rejection of spurious stuff.



Indeed it is .. we once used around three miles of phone cable overhead
and underground for an RSL and apart from a bit of "top" loss its was
very quiet indeed;)..
--
Tony Sayer

AKG C451 mics
 

"Dave Plowman (News)"

You'd be surprised. Some time ago I made up 100v line XLR cables using
ordinary mains 2 core flex. Cheaper than screened cable. And found one in
use with a dynamic hand mic - because it was a nice shiny white, rather
than the more usual mic cable grey or black. And apparently worked just
fine. In other words it's the balancing that gives the majority of the
rejection of spurious stuff.


** If you wire a twin shielded mic cable in unbalanced mode - there is no
problem either.

Proving beyond doubt that balancing is irrelevant to noise rejection with
mics.

However - *IF* an unshielded pair is used for a mic, balancing ( plus
good RF rejection) becomes critical to a usable result.




..... Phil

AKG C451 mics
 

On Sun, 31 May 2009 13:21:11 +0100, tony sayer
wrote:

In article 4a2816f3.105242859@localhost, Don Pearce
scribeth thus
On Sat, 30 May 2009 11:21:17 GMT, "Brian Gaff"
wrote:

If you lose the screen you will probably get radio Moscow instead..grin.

Brian

At least that might be interesting. It's always minicabs.

d

When did you hear minicab radio breakthrough last?..

Seeing that AM has been out of fashion for some 20 years now?.

At least in the UK...

That's probably when I last heard it! In fact not since I last used
valves and suffered from a rectifying contact in the socket.

d

AKG C451 mics
 

On Sun, 31 May 2009 13:22:33 +0100, tony sayer
wrote:

Indeed it is .. we once used around three miles of phone cable overhead
and underground for an RSL and apart from a bit of "top" loss its was
very quiet indeed;)..

I was once told that the cables on telephone posts are arranged to
form a twisted pair. (I.e. the cables move from insulator to
insulator so that they twist around each other.)

Pardon my ignorance, but what is an RSL?

Thanks,

--
Chris Isbell
Southampton, UK

AKG C451 mics
 

In article , Chris Isbell
scribeth thus
On Sun, 31 May 2009 13:22:33 +0100, tony sayer
wrote:

Indeed it is .. we once used around three miles of phone cable overhead
and underground for an RSL and apart from a bit of "top" loss its was
very quiet indeed;)..

I was once told that the cables on telephone posts are arranged to
form a twisted pair. (I.e. the cables move from insulator to
insulator so that they twist around each other.)

Well they are twisted to stop crosstalk like the wires in a CAT 5
cable..

Pardon my ignorance, but what is an RSL?


Sorry .. Restricted Service Licence a form of short term broadcast
licence usually for FM radio normally issued for some event or other.

In this instance with was used to link two studios together...
Thanks,


--
Tony Sayer

AKG C451 mics
 

Dave Plowman (News) wrote:

You'd be surprised. Some time ago I made up 100v line XLR cables using
ordinary mains 2 core flex. Cheaper than screened cable. And found
one in use with a dynamic hand mic - because it was a nice shiny
white, rather than the more usual mic cable grey or black. And
apparently worked just fine. In other words it's the balancing that
gives the majority of the rejection of spurious stuff.


I'm told that Cat 5 Ethernet cable also works great for audio if you need
several channels, presumably because the pairs are tightly twisted. The
other advantage is that it is relatively cheap.

AKG C451 mics
 

"Chris Isbell" wrote in message
...
On Sun, 31 May 2009 13:22:33 +0100, tony sayer
wrote:

Indeed it is .. we once used around three miles of phone cable overhead
and underground for an RSL and apart from a bit of "top" loss its was
very quiet indeed;)..

I was once told that the cables on telephone posts are arranged to
form a twisted pair. (I.e. the cables move from insulator to
insulator so that they twist around each other.)

Pardon my ignorance, but what is an RSL?

Thanks,

--
Chris Isbell
Southampton, UK

A Restricted Service License. Ofcom, the UK government Regulator for
Broadcasting, issues temporary licenses for special events. Typically they
are for 30 days in any one year, on FM, and usually power is limited to
25watts ERP or less.

Some RSLs, like our Hospital Radio Station are long-term, but we are
restricted to broadcasting to the local Hospital on AM, and are not allowed
to acknowledge on-air any listeners from outside the Hospital grounds that
may be listening to us. By going on the Internet, we can now acknowledge
outside listeners, but must be careful not to imply that they heard us on
1350.

RSLs are an expensive way to get on-air, as Ofcom charge a lot of money,
£2000 if I remember correctly for 30 days broadcasting a year or to a tiny
area.

S.
--
http://audiopages.googlepages.com

AKG C451 mics
 

On Sun, 31 May 2009 17:34:31 +0100, Chris Isbell
wrote:

On Sun, 31 May 2009 13:22:33 +0100, tony sayer
wrote:

Indeed it is .. we once used around three miles of phone cable overhead
and underground for an RSL and apart from a bit of "top" loss its was
very quiet indeed;)..

I was once told that the cables on telephone posts are arranged to
form a twisted pair. (I.e. the cables move from insulator to
insulator so that they twist around each other.)

Pardon my ignorance, but what is an RSL?


I presume he's talking about a Restricted Service License. This would
be something like a special temporary FM transmitter serving an event
(the British Grand Prix will certainly have one next month).

It would need a signal feed from a studio somewhere.

d

AKG C451 mics
 

Don Pearce wrote..


That's probably when I last heard it! In fact not since I last used
valves and suffered from a rectifying contact in the socket.

All you'd hear today is a short databurst.
http://www.cabmaster.com/

--
Ken
http://unsteadyken.sitegoz.com/

AKG C451 mics
 

In article , UnsteadyKen
scribeth thus
Don Pearce wrote..


That's probably when I last heard it! In fact not since I last used
valves and suffered from a rectifying contact in the socket.

All you'd hear today is a short databurst.
http://www.cabmaster.com/

You'd be very lucky to hear that or would have to be in the taxi!..

Despite all the GPRS data they still use the voice radio to sort out all
the things that data messaging can't!..
--
Tony Sayer

AKG C451 mics
 

In article , TonyL
scribeth thus
Dave Plowman (News) wrote:

You'd be surprised. Some time ago I made up 100v line XLR cables using
ordinary mains 2 core flex. Cheaper than screened cable. And found
one in use with a dynamic hand mic - because it was a nice shiny
white, rather than the more usual mic cable grey or black. And
apparently worked just fine. In other words it's the balancing that
gives the majority of the rejection of spurious stuff.


I'm told that Cat 5 Ethernet cable also works great for audio if you need
several channels, presumably because the pairs are tightly twisted. The
other advantage is that it is relatively cheap.






Yes it does its also very good for ordinary phone comms..
--
Tony Sayer

AKG C451 mics
 

"Chris Isbell" wrote in message
...
On Sun, 31 May 2009 13:22:33 +0100, tony sayer
wrote:

Indeed it is .. we once used around three miles of phone cable overhead
and underground for an RSL and apart from a bit of "top" loss its was
very quiet indeed;)..

I was once told that the cables on telephone posts are arranged to
form a twisted pair. (I.e. the cables move from insulator to
insulator so that they twist around each other.)

Open -wires were arranged that way. Two pairs on 4 insulators were rotated
90 degrees every so often forming a quad. But therse all went out of use
years ago, in overhead cables the pairs are twisted inside the cable.

David.