Dirty Digital [sic.]
 

In article , Phil Allison
scribeth thus

"tony sayer"

YOU have no ****ing idea how common it is to find audio gear that is RF
sensitive.

No I suppose not. A career that spanned TV transmitters up to 40 kW
transposers to 2 kW ReBroadcast receivers and demodulators , AM
Transmitters to sever hundred kW and FM to some 40 odd..

Audio equipment by Rupert Neve and Audix, Pye TvT, Work with the UK
radio communications agency radio communications investigation service,
the BBC, Cambridge university, cellular and communication radio sites
broadcast sites...

No I suppose not;!..


** So you have ZERO idea about the gear musos use and how commonly it is
sensitive to RFI - cos you have no experience of it.

Your musos over there must have some very ropey gear indeed;)..

So you have no idea that full room RFI screening of sound recording studios
has been standard practise since the 1960s.

Has it really!, even good broadcast ones?..

So you have no idea that the RFI issues have got WORSE, not better, since
that time.


Nope we've found them to be better as regards susceptibility and
generation and considering the number of mobile phones around thats very
good going.

If you make the rule that mobiles shouldn't be in studios when people
have bought their own old gear in then you've no practical need to go to
all that bother and expense to screen them both 'agin magnetic fields
and RF ones .. DC to daylight. Modern wired in studio equipment using
balanced line working is very immune to this as is CAT 5 cabling..

You agree the laws of physics have not changed.


Strewth M8 ! get a life will yer!, you've got about the same sense of
humour as my Sheila;!..


G'day.....

--
Tony Sayer

Dirty Digital [sic.]
 

In article , Phil Allison
scribeth thus

"Dave Plowman (News)"
Eeyore :

Phil is as is usually the case very much correct. There's heaps of utter
****e out there to this day, 'designed' by clots without the first clue
about RF susceptibility (or what 'ground' really is !).

Then don't use it. I don't.

If you're talking about crappy guitar amps etc then screen them in the
studio rather than spend millions attempting to screen the studio when
it's simply not needed.


** RFI screening a recording studio does not cost millions - nothing like
it.

Compared to the elaborate sound-proofing, acoustic treatment and installing
silent air-con - it is a puny additional cost.




Normally achieved by fitting copper mush ( ie coper fly wire) over all the
internal surfaces of the studio and control room. Joins are folded and
soldered together.

Seen the cost of copper nowadays?, akin to a semi precious metal!. The
Pikeys will have it away in no time.


Means the studio can use any piece of gear they like and musos can drag
in
any old pile of valve or antique transistor junk
without fear a passing taxi or police car transmitter will break in
during a
session.

blimey! are they still using spark transmitters down the?..


A very simple, common sense precaution.

Incomprehensible to folk who have no common sense.

****wits like Sayer, Plowman and Pearce - for example.

Including you then.!..

--
Tony Sayer

Dirty Digital [sic.]
 

The ability to de-modulate strong RF signals is built into most items of
audio gear - the valves and transistors at the input do it. The RF energy
enters the circuitry on the signals and sometimes the speaker cables.

Such connecting cables act as antennas and the RF signal goes straight in on
the braided copper shields of 1/4 inch guitar and XLR leads.

Many classic guitar amps like Marshalls are very prone to this form of RF
injection.

Could you then explain the way this happens in detail if you wish and --
-especially- with valved equipment's?..


A mobile phone can also cause problems with older gear, but it must be
fairly close in order to do so.

So the megawatt spark transmitter taxis don't cause problems then?..


--
Tony Sayer

Dirty Digital [sic.]
 

My friends at Westwick don't get continual repeat business (from top clients)
by being crap at their job.

Don't suppose they don't .. seems however they do go for overkill which
isn't good engineering. After all its not rocket science building a
studio..


Normally achieved by fitting copper mush ( ie coper fly wire) over all the
internal surfaces of the studio and control room. Joins are folded and
soldered together.

The UK contractor Westwick uses prefers sheet steeel with continuous weld, but
I've used copper mesh elsewhere with good results. They also have some neat
method for dealing with windows that's a damn clever structure and keeps them
fairly EMC opaque.

Yep use the same ones as on a Voyager, high lead content;!..



Means the studio can use any piece of gear they like and musos can drag in
any old pile of valve or antique transistor junk

Oh Lord ! Could I tell you a story there !


without fear a passing taxi or police car transmitter will break in during a
session.

Have you noticed that for sometime now the old bill have used quite low
powered handsets?. And that more and more Taxi firms are using GSM for
comms?..and they left AM a long-time ago and the only, it seems use
spark Tx's in the bad lands of Oz;.....


--
Tony Sayer

Dirty Digital [sic.]
 

"Dave Plowman (News)" wrote:

Phil Allison wrote:
Most electric guitars are very prone to ( audio frequency) electric
fields - cos the pickups have no ES shields and some of the wiring is
also unshielded.

As a result - most electric guitar become nearly unusable in close
proximity (ie a few metres) to mains frequency driven fluoro lighting
or triac dimmed lighting.

Oh dear. You allow that unsorted in 'your' studio while spending millions
on screening?

You fit grounded wire mesh 'socks' over any fluoro tubes.


Rule one for you amateurs. Don't provide a source of interference in your
studio when it can be avoided. Prevention is better than cure.

The other lighting is DC halogen controlled by variable output SMPSs.

Graham

Dirty Digital [sic.]
 

Phil Allison wrote:

"Don Pearce = Posturing ****** "

But if what you want is an EMI shield, you don't make an enormously
expensive steel box - any simple and cheap conductive mesh will do as
well.

** Take that up with Eeyore.

It was the recommendation of the EMC company who fitted it all. Blowed If I can
remember their name now, I recall they make 19" racking kit too.

According to them the thickness of the material is important and they use as
much as they consider is required.

Graham

Dirty Digital [sic.]
 

Don Pearce wrote:

Guitarists who are serious and understand the
issues modify their guitars to screen all the electrics.

No. Most who own old originals won't let an engineer anywhere near them lest
it 'modify' the sound.

Graham

Dirty Digital [sic.]
 

Don Pearce wrote:

Combine that with humbucking pickups

And the sound will change.

Graham

Dirty Digital [sic.]
 

"Dave Plowman (News)" wrote:

Rather like those who see their favourite pop vocalist using an SM58 etc and
assume
it's the best mic ever made...

A mic I loathe with a vengeance.

Graham

Dirty Digital [sic.]
 

Eeyore wrote:

Don Pearce wrote:

Guitarists who are serious and understand the
issues modify their guitars to screen all the electrics.

No. Most who own old originals won't let an engineer anywhere near them lest
it 'modify' the sound.

Graham


It's no problem. Every top guitarist has a tech who works on his guitars
- they need constant fettling if they are to stay playing well, and
adding screening to the cavities is just one of the tasks that is standard.

d