[Steve Parker[_2_]]

What is the consensus on coiling short to medium length cables.
Say less than 25 ft.
I'm old school and over and under just about everything, but I'm
running into a lot grips/2nds who just straight coil a 20 footer.
Mind you, I've never had a problem when I've asked for an over and
under, and they seem to naturally go over and under on longer runs.

Anyway, am I being picky???


-


Steven Parker

Video Production Specialist
ITCS/ACES
67A Mumford Hall, MC-710
University of Illinois
Urbana, IL 61801

"I absolutely refuse to be anonymous.
Don't use handles. Use your real name.
Have the conviction to identify your ideas."

[Don Pearce[_3_]]

On Mon, 08 Jun 2009 10:50:44 -0500, Steve Parker
wrote:

What is the consensus on coiling short to medium length cables.
Say less than 25 ft.
I'm old school and over and under just about everything, but I'm
running into a lot grips/2nds who just straight coil a 20 footer.
Mind you, I've never had a problem when I've asked for an over and
under, and they seem to naturally go over and under on longer runs.

Anyway, am I being picky???

If you have cables that need cooling, they are made with far too thin
a wire gauge. Get fatter cables.

If you are talking about signal cables - mics I guess - then coiling
them makes no difference. The coils are in common mode, the signal in
differential mode. Just make them tidy so no-one trips.

d

[Mike Rivers]

Steve Parker wrote:

I'm old school and over and under just about everything, but I'm
running into a lot grips/2nds who just straight coil a 20 footer.

It's just a matter of personal preference. I know people who never
use over-and-under because it's too easy to end up with a string
of knots if you're not careful when uncoiling it.

I use over-and-under for cables that get too heavy for me to hold
up while coiling them, because that seems to work better when
laying the coil on the ground or in a box. I tend to coil short
cables over-and-over.

I never use the fold-it-in-half, fold-it-in-half-again, and again, and again
method, but some people use nothing else.


--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Steve Parker[_2_]]

Personally I've never had the knot problem.
But I could see this being a problem with new/starting out crew.
I may have to rethink this..

And I have never been able to make the fold and fold again work for me.

-


Steven Parker



Mike Rivers wrote:
Steve Parker wrote:

I'm old school and over and under just about everything,..

It's just a matter of personal preference. I know people who never
use over-and-under because it's too easy to end up with a string
of knots if you're not careful when uncoiling it.

[Don Pearce[_3_]]

On Mon, 08 Jun 2009 15:58:09 GMT, (Don Pearce) wrote:

On Mon, 08 Jun 2009 10:50:44 -0500, Steve Parker
wrote:

What is the consensus on coiling short to medium length cables.
Say less than 25 ft.
I'm old school and over and under just about everything, but I'm
running into a lot grips/2nds who just straight coil a 20 footer.
Mind you, I've never had a problem when I've asked for an over and
under, and they seem to naturally go over and under on longer runs.

Anyway, am I being picky???

If you have cables that need cooling, they are made with far too thin
a wire gauge. Get fatter cables.

If you are talking about signal cables - mics I guess - then coiling
them makes no difference. The coils are in common mode, the signal in
differential mode. Just make them tidy so no-one trips.

d

Ok, I see I got your meaning wrong. I prefer to keep long cables on
drums, and wind them on and off without twist. If I have no drum for a
long cable, I use a figure-8 drape that has no net twist.

d

[Roy W. Rising[_2_]]

(Don Pearce) wrote:
On Mon, 08 Jun 2009 10:50:44 -0500, Steve Parker
wrote:

What is the consensus on coiling short to medium length cables.
Say less than 25 ft.
I'm old school and over and under just about everything, but I'm
running into a lot grips/2nds who just straight coil a 20 footer.
Mind you, I've never had a problem when I've asked for an over and
under, and they seem to naturally go over and under on longer runs.

Anyway, am I being picky???

I coil everything ... cables, ropes, hoses, test leads ... *everything*
over and under.

I do it in hand with smaller things, on the floor for larger ones. "Figure
eight" is good for things like camera cables that have to pay out as the
camera trucks away from the anchor point.

There's a certain satisfaction to holding onto one end of a 100' mic cable
and throwing the coil across a stage, watching it land straight-arrow on
the deck.

The problem of knots comes from allowing the end you hold to have slipped
through the center so it is on the wrong side of the coil.

--
~ Roy
"If you notice the sound, it's wrong!"

[Richard Crowley]

"Don Pearce" wrote ...
(Don Pearce) wrote:
Steve Parker wrote:
What is the consensus on coiling short to medium length cables.
Say less than 25 ft.
I'm old school and over and under just about everything, but I'm
running into a lot grips/2nds who just straight coil a 20 footer.
Mind you, I've never had a problem when I've asked for an over and
under, and they seem to naturally go over and under on longer runs.

Anyway, am I being picky???

If you have cables that need cooling, they are made with far too thin
a wire gauge. Get fatter cables.

If you are talking about signal cables - mics I guess - then coiling
them makes no difference. The coils are in common mode, the signal in
differential mode. Just make them tidy so no-one trips.


Ok, I see I got your meaning wrong. I prefer to keep long cables on
drums, and wind them on and off without twist. If I have no drum for a
long cable, I use a figure-8 drape that has no net twist.

Except for short (15 ft, 5m) cables, I keep mine plugged end-to end
and rolled up on those orange hand reels sold at home improvement
stores for storing electrical extension cords. I have around a dozen of
them for 3-pin standard XLR, 5-pin "stereo" XLR, speaker, power,
and BNC (video) cables. They are generally easier for amateur helpers
to manage who otherwise have no special cable management experience.

It makes them easier to deploy quickly as one can just pull off as much
as needed quickly. And then when rolling them up during the strike, one
can use a damp towel to clean off the cable (and tension it) as it is rolled
back onto the reels.

The short cables (and jumpers, adapters, etc.) I keep coiled ~6~8
inches diameter with the end looped through to hold it together, etc.
and put into the appropriate box. I have separate boxes for short
XLR cables, RCA cables, BNC cables, and one for IEC power
cables and power strips.

Big heavy cables (multi-core TV camera cables, etc.) are done in
the figure-8 stacking as Mr. Pearce describes, but I don't find that
as practical for smaller cables except in a fixed situation. All my stuff
is mobile.

[Scott Dorsey]

Steve Parker wrote:
What is the consensus on coiling short to medium length cables.
Say less than 25 ft.
I'm old school and over and under just about everything, but I'm
running into a lot grips/2nds who just straight coil a 20 footer.
Mind you, I've never had a problem when I've asked for an over and
under, and they seem to naturally go over and under on longer runs.

Anyway, am I being picky???

A straight coil is fine, though it takes a little bit longer, as long
as you actually pay attention to how the cable wraps. Wrap it like a
rope, don't just roll it up and let it turn into a damaged mess.

I'd be happy if I could just get people to realize how bad elbow wrapping is.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Steve Parker[_2_]]

There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling extends a
cables life. I have some mic cables that are over 20 years old. Tjey
still work fine.
-


Steven Parker

Video Production Specialist
ITCS/ACES
67A Mumford Hall, MC-710
University of Illinois
Urbana, IL 61801

"I absolutely refuse to be anonymous.
Don't use handles. Use your real name.
Have the conviction to identify your ideas."



Scott Dorsey wrote:
Steve Parker wrote:
What is the consensus on coiling short to medium length cables.

A straight coil is fine, though it takes a little bit longer, as long
as you actually pay attention to how the cable wraps. Wrap it like a
rope, don't just roll it up and let it turn into a damaged mess.

I'd be happy if I could just get people to realize how bad elbow wrapping is.
--scott

[Richard Crowley]

"Steve Parker" wrote ...
There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling extends a
cables life. I have some mic cables that are over 20 years old. Tjey still
work fine.

I use mic cables I made in the mid 1970s that still work fine today.
(At least the half of them I haven't lost along the way.) I used the
small, real rubber Belden mic cable (#?) and Switchcraft A3M/A3F.

[Don Pearce[_3_]]

On Mon, 08 Jun 2009 15:17:50 -0500, Steve Parker
wrote:

There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling extends a
cables life. I have some mic cables that are over 20 years old. Tjey
still work fine.

Someone has kindly filmed a demo of the over/under method

http://members.cox.net/mactop/

d

[[email protected]]

On 2009-06-08 (ScottDorsey) said:
A straight coil is fine, though it takes a little bit longer, as
long as you actually pay attention to how the cable wraps. Wrap it
like a rope, don't just roll it up and let it turn into a damaged
mess.

I would agree with this wholeheartedly.

I'd be happy if I could just get people to realize how bad elbow
wrapping is. --scott
I would too.

What I'd be even happier with is if I oculd find some bins
on wheels that would accomodate my snakes and my power
feeder cables for remote truck. I bought a couple of
plastic bins at WAl Mart, but they're not on wheels, sort
of unwieldy on a hand truck, and not that rugged imho.
I"m looking at biting the bullet and building something
myself out of wood, though it would be damned heavy.





Richard webb,
replace anything before at with elspider

[Mike Rivers]

Steve Parker wrote:
Personally I've never had the knot problem.
But I could see this being a problem with new/starting out crew.

It can occur if the free end slips thorugh the center of the coil. I
actually
first learned how to make a string of knots when I was talking with a
sailor.
He showed me what he called a "monkey line" made by coiling a rope
"over and under", passing the free end through the center, and shaking
out the coil. They use it to make an emergency rope ladder.



--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Neil[_7_]]

On Mon, 08 Jun 2009 15:17:50 -0500, Steve Parker
wrote:

There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling extends a
cables life. I have some mic cables that are over 20 years old. Tjey
still work fine.
-
Elbow wrapping is fine if you do it properly. I have cables I have
been elbow wrapping for 20 years and they are fine. Do not pull or
wrap tightly, ensure you don't coil the twists!
Only with short -10 metres of course.
neil

[Arny Krueger]

"Steve Parker" wrote in message
...
There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling extends a
cables life. I have some mic cables that are over 20 years old. They still
work fine.

Not to be contrary, but I have cables that might be over 50 years old, ere
used very haphazardly, and they are still fine, just getting a little stiff.
;-)

[Jay Ts]

Arny Krueger wrote:
"Steve Parker" wrote
There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling extends
a cables life. I have some mic cables that are over 20 years old. They
still work fine.

Not to be contrary, but I have cables that might be over 50 years old,
ere used very haphazardly, and they are still fine, just getting a
little stiff. ;-)

I don't doubt it, but weren't they using much tougher construction
then? Like maybe braided copper wire for the shield, and not thin metal
foil?

There are (have been) so many different types of cable. Maybe some are
more easily damaged by twisting than others.

I'd like to see a study too. Maybe someone could make a machine that
stretches a length of cable, then twists it one direction, then the
other, for a torture test. Then compare its electrical properties before
and after - capacitance, resistance, inductance, and especially, the
ability of the shield to keep noise levels low.

I'd also like to see the results of a "run over by casters" test.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

[Richard Crowley]

Jay Ts wrote:
Arny Krueger wrote:
"Steve Parker" wrote
There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling
extends a cables life. I have some mic cables that are over 20
years old. They still work fine.

Not to be contrary, but I have cables that might be over 50 years
old, ere used very haphazardly, and they are still fine, just
getting a little stiff. ;-)

I don't doubt it, but weren't they using much tougher construction
then? Like maybe braided copper wire for the shield, and not thin
metal foil?

But OTOH, some of the old rubber cables start to get hard and
crack, etc so the cable insulation itself may be the failure mode.

[Scott Dorsey]

Jay Ts wrote:
Arny Krueger wrote:
"Steve Parker" wrote
There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling extends
a cables life. I have some mic cables that are over 20 years old. They
still work fine.

Not to be contrary, but I have cables that might be over 50 years old,
ere used very haphazardly, and they are still fine, just getting a
little stiff. ;-)

I don't doubt it, but weren't they using much tougher construction
then? Like maybe braided copper wire for the shield, and not thin metal
foil?

You can buy cable like that today. You will have to pay more money than
for crap, but it's worth the money.

I'd like to see a study too. Maybe someone could make a machine that
stretches a length of cable, then twists it one direction, then the
other, for a torture test. Then compare its electrical properties before
and after - capacitance, resistance, inductance, and especially, the
ability of the shield to keep noise levels low.

Belden has done all of this stuff. If you ask Steve Lampen, he'll send
you all kinds of propaganda.

I'd also like to see the results of a "run over by casters" test.

I don't know, but I _do_ know that the served shield that msot of the Mogami
cables use can be damaged very badly by rolling a piano over the cable.
The braid shields seem okay.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Peter Larsen[_3_]]

Richard Crowley wrote:

| I use mic cables I made in the mid 1970s that still work fine today.
| (At least the half of them I haven't lost along the way.) I used the
| small, real rubber Belden mic cable (#?)

102-06, Sennheisers with RFI proof dual layer twist screen?

and Switchcraft A3M/A3F.

Kind regards

Peter Larsen

[Al, Cambridge, UK]

On Jun 8, 9:47*pm, wrote:
On 2009-06-08 (ScottDorsey) said:
* *A straight coil is fine, though it takes a little bit longer, as
* *long as you actually pay attention to how the cable wraps. *Wrap it
* *like a rope, don't just roll it up and let it turn into a damaged
* *mess.

I would agree with this wholeheartedly.

* *I'd be happy if I could just get people to realize how bad elbow
* *wrapping is. --scott
I would too.

What I'd be even happier with is if I oculd find some bins
on wheels that would accomodate my snakes and my power
feeder cables for remote truck. *I bought a couple of
plastic bins at WAl Mart, *but they're not on wheels, sort
of unwieldy on a hand truck, and not that rugged imho.
I"m looking at biting the bullet and building something
myself out of wood, though it would be damned heavy.

Richard webb,
replace anything before at with elspider

I think www.sommercable.com (Germany) make flightcases with vertical
drums for heavy multicore snakes, but I can't find product on their
website - may have been in their paper catalogue.
Or it might be www.studiospares.com (UK), also can't find product.

[Arny Krueger]

"Jay Ts" wrote in message
.com...
Arny Krueger wrote:
"Steve Parker" wrote
There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling extends
a cables life. I have some mic cables that are over 20 years old. They
still work fine.

Not to be contrary, but I have cables that might be over 50 years old,
ere used very haphazardly, and they are still fine, just getting a
little stiff. ;-)

I don't doubt it, but weren't they using much tougher construction
then? Like maybe braided copper wire for the shield, and not thin metal
foil?

Point well taken.

There's a middle ground - many modern cables use fine stranded wire in a
loose wrap. Braid looks more elegant but I don't know if it really that
much better.

Nobody in their right mind uses foil jacketed cable for mic cables, do they?
I thought foil was only for permanent installations.

There are (have been) so many different types of cable. Maybe some are
more easily damaged by twisting than others.

The most common signs of abuse leading to hard failure I see is the outer
jacket ripped by heavy abrasion or crushing, and cables just completely torn
apart by twirling.

I'd like to see a study too. Maybe someone could make a machine that
stretches a length of cable, then twists it one direction, then the
other, for a torture test. Then compare its electrical properties before
and after - capacitance, resistance, inductance, and especially, the
ability of the shield to keep noise levels low.

That would be a good test. I wonder if people like Belden do such things.

I'd also like to see the results of a "run over by casters" test.

Unh yes, the steel casters running over a cement floor. Ouch!

But I've seen jackets torn apart by feet on carpeting.

[Jay Ts]

Arny Krueger wrote:
"Jay Ts" wrote:
Arny Krueger wrote:
"Steve Parker" wrote
There are people who I will not hire because they could not break
themselves of the habit of elbow wrapping.

I wonder if anyone has done a study of how long proper coiling
extends a cables life. I have some mic cables that are over 20 years
old. They still work fine.

Not to be contrary, but I have cables that might be over 50 years old,
ere used very haphazardly, and they are still fine, just getting a
little stiff. ;-)

I don't doubt it, but weren't they using much tougher construction
then? Like maybe braided copper wire for the shield, and not thin metal
foil?

Point well taken.

There's a middle ground - many modern cables use fine stranded wire in a
loose wrap. Braid looks more elegant but I don't know if it really that
much better.

Nobody in their right mind uses foil jacketed cable for mic cables, do
they? I thought foil was only for permanent installations.

I wasn't thinking about mic cable, rather guitar cable. I've been
searching for guitar cable I like for at least the past 15 years, and
still haven't found any.

I like braided copper shield because the wires in it coil in opposite
directions, and hold each other in place. I think a loose wrap of fine
stranded wire is used in mic cables to allow the cables to be more
flexible. But I suspect it also makes the cable more vulnerable to
developing gaps in the shield. With balanced mic cable, that's more
acceptable than in unbalanced guitar cable.

I've seen foil shielded cable sold as guitar cable. It was a long time
ago when I didn't know any better than to buy it, and it became a
learning experience for me.

From that, I realized that cables may need to be treated more nicely than
I would think, especially if it's some off brand product I don't
recognize. Many guitar cables are sold with molded connectors, and
there's no easy way to know what's in there without ruining the cable.

The most common signs of abuse leading to hard failure I see is the
outer jacket ripped by heavy abrasion or crushing, and cables just
completely torn apart by twirling.

I'm more concerned about soft failure, such as spaces in the shield
gradually opening up over time, and the cable's electrical properties
(especially capacitance) changing. I think that repeated twisting of the
cable plausibly could cause these, at least for some kinds of cables.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

[Scott Dorsey]

Jay Ts wrote:

I wasn't thinking about mic cable, rather guitar cable. I've been
searching for guitar cable I like for at least the past 15 years, and
still haven't found any.

Make your own. I rather like the Canare instrument cable, but some of
the low-triboelectric-noise cables from Belden actually make great
instrument cables. They are hard to kill.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Jay Ts]

Scott Dorsey wrote:
Jay Ts wrote:

I wasn't thinking about mic cable, rather guitar cable. I've been
searching for guitar cable I like for at least the past 15 years, and
still haven't found any.

Make your own.

I do.

I rather like the Canare instrument cable,

I don't. Canare GS-6 has 49 pF of capacitance per foot, and I'm trying
to get down around 25-30 pF/ft.

Right now, I'm using Mogami 2425, which has just under 40 pF/ft.
Not great, but at least it's better than the Canare.

Capacitance per foot is my #1 priority. It's to minimize shifts of tone
when playing my guitar with passive pickups, not an active circuit.
(Usually I play with the active circuit turned on, to minimize effects of
cable capacitance, but sometimes I like to switch to the passive sound.)

For anyone who didn't understand that, go read this:
http://www.buildyourguitar.com/resou...emme/index.htm

If you don't have time or it's too technical, just skip to the bottom and
look at figure 15.

but some of
the low-triboelectric-noise cables from Belden actually make great
instrument cables.

I know a lot of people love Belden, but every time I've checked Belden's
products, I've come up with nothing better than the Mogami cable I'm
using, or what I was using before that (Carol #1300, which I can no
longer find sold by the foot, if at all.)

Belden lists a #8410 instrument cable, with 33 pF/ft, but I find the
other specs too lacking: a thin, 25 AWG conductor, and just 80% shield
coverage. Their other single-conductor, high-impedance cables all have
too much capacitance.

Specifically, what Belden cables did you have in mind? If they have any
mic or other cable with the right specs, I'd like to know about it. BTW,
I really don't care about toughness, as long as the cable has good
electrical specs. I'll be happy to coil it properly, and keep it from
being run over or stepped on.

What I really want is something like Klotz instrument cable AC110 (22 pF/
ft) or maybe AC106 (29 pF/ft), but I haven't been able to find anyone who
sells it by the foot. (I don't have much use for 100 meters of guitar
cables!)

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

[Chris Hornbeck]

On 11 Jun 2009 04:02:50 GMT, Jay Ts
wrote:

Capacitance per foot is my #1 priority. It's to minimize shifts of tone
when playing my guitar with passive pickups, not an active circuit.
(Usually I play with the active circuit turned on, to minimize effects of
cable capacitance, but sometimes I like to switch to the passive sound.)

Assuming that you don't believe in any magical properties
in guitar cables (some do; could even be true; don't ask me)
maybe all you need for a robust translatible sound is a
choice of loading capacitances upstream of your active
buffer.

I might otter incorporate that in my next guitar amp build.
More damn switches.

Much thanks,
Chris Hornbeck

[Jay Ts]

Chris Hornbeck wrote:
Jay Ts wrote:

Capacitance per foot is my #1 priority. It's to minimize shifts of tone
when playing my guitar with passive pickups, not an active circuit.
(Usually I play with the active circuit turned on, to minimize effects
of cable capacitance, but sometimes I like to switch to the passive
sound.)

Assuming that you don't believe in any magical properties in guitar
cables (some do; could even be true; don't ask me) maybe all you need
for a robust translatible sound is a choice of loading capacitances
upstream of your active buffer.

That was a good guess, and you were very close!

After reading the Lemme article, I spent many hours playing around adding
capacitance and/or resistance across the pickups, to see if I could
improve my guitar's passive sound. If you have the parts handy, it's
pretty easy to reproduce the effect he shows in his plots, and hear it to
experience the effect for yourself.

What I learned was that the pickups that I planned to replace "someday"
were actually quite good, once the resonant peak was sufficiently muted.
After some experimentation with altering the resonant frequency, I
realized that it was the peak itself that was bothering me, and wrecking
the sound of my guitar when played through studio monitors!

So I put a 250K thumbwheel trimpot across the pickups ahead of the active
circuitry, and adjusted it to a balance I like. (Too low, and it drops
the high frequencies too much. Too high, and the resonant peak becomes
objectionable).

Now my guitar sounds a lot better -- either with the active circuit on or
off. When used passively, for sufficiently low-capacitance cables, the
audible effect of the cable is diminished because there is no resonant
peak. The cable just acts to change the lowpass frequency of the pickup,
which is no longer such a critical factor.

I might otter incorporate that in my next guitar amp build. More damn
switches.

Try changing your guitar first! A $1.50 trimpot saved me the expense of
new pickups, which might not have solved anything.

If you like the sound of pickup resonance, rip the stupid tone controls
out of your guitar and replace them with a rotary switch and capacitors
as Helmuth Lemme suggests. He's not kidding when he says you get a lot
more creative control with one of those than you do with typical guitar
tone controls.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

[Mike Rivers]

Jay Ts wrote:

Capacitance per foot is my #1 priority. It's to minimize shifts of tone
when playing my guitar with passive pickups, not an active circuit.
(Usually I play with the active circuit turned on, to minimize effects of
cable capacitance, but sometimes I like to switch to the passive sound.)

For anyone who didn't understand that, go read this:
http://www.buildyourguitar.com/resou...emme/index.htm

If you don't have time or it's too technical, just skip to the bottom and
look at figure 15.

Also, look at Figure 16. He calls this an "inferior" pickup, but to me
(with my
engineer's hat on - I don't have an electric guitarist's hat), it looks
like with
what's a fairly typical amplifier load, it's pretty good - no resonant
peak to
tame, and a gentle rolloff down to about 3.5 or 4 kHz.

It really depends on whether your preferred sound can take advantage of
a resonant peak to bring out what's there above 3 kHz, or whether it gets
in the way either as harshness or noise. I can see that if you want that
high
end boost and increase the capacitive load, while you can move the peak
around a bit, the greatest effect will be to increase the high frequency
rolloff.

The author of that article has something to sell. But I guess you know what
you like when you hear it.

Belden lists a #8410 instrument cable, with 33 pF/ft, but I find the
other specs too lacking: a thin, 25 AWG conductor, and just 80% shield
coverage.

The way to make a low capacitance cable is to make the "plates" as far
apart as possible. You can make the overall cable larger in diameter, but
in order to keep it reasonable, you need to make the inner conductor smaller
in diameter so it has a smaller surface area. You can make a cable with
much lower capacitance, but it would be about the size of a garden hose.

What I really want is something like Klotz instrument cable AC110 (22 pF/
ft) or maybe AC106 (29 pF/ft), but I haven't been able to find anyone who
sells it by the foot. (I don't have much use for 100 meters of guitar
cables!)

You could do what others do - build and sell expensive cables. After the
first
20 or 30 sales, you'll have paid for your own set of cables, and then when
someone on line poo-poos your cables as being filled with snake oil, you can
stop advertising.

Run the numbers. What's the difference in frequency response between your
pickup with an extra 400 pF across it (the difference between 30 and 50
pF/ft
for a 20 foot cable)? And more important, is it sonically significant?

--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[WillStG]

On Jun 8, 3:11*pm, (Scott Dorsey) wrote:
Steve Parker wrote:

What is the consensus on coiling short to medium length cables.
Say less than 25 ft.
I'm old school and over and under *just about everything, but I'm
running into a lot grips/2nds who just straight coil *a 20 footer.
Mind you, I've never had a problem when I've asked for an over and
under, and they seem to naturally go over and under on longer runs.

Anyway, am I being picky???

A straight coil is fine, though it takes a little bit longer, as long
as you actually pay attention to how the cable wraps. *Wrap it like a
rope, don't just roll it up and let it turn into a damaged mess.

Well if you want to lasso a steer, you have to over and under your
lariat or you can't just throw it and not have it get tangled. Wire
is wound generally like rope is, and both want to naturally wrap over
and under. Video Tri-Ax cable is the same, but being heavy guys
sometimes lay it on the floor in a figure 8 and then fold it over,
same thing.

I'd be happy if I could just get people to realize how bad elbow wrapping is.

Think Cowboys and Sailors have this same discussion about wrapping
ropes?

Will Miho
NY TV/Audio Post/Music/Live Sound Guy
"The large print giveth and the small print taketh away..." Tom Waits

[Scott Dorsey]

Jay Ts wrote:

I rather like the Canare instrument cable,

I don't. Canare GS-6 has 49 pF of capacitance per foot, and I'm trying
to get down around 25-30 pF/ft.

Right now, I'm using Mogami 2425, which has just under 40 pF/ft.
Not great, but at least it's better than the Canare.

Well, this is the problem. If you want low capacitance, you need small
structures, and that means fragile cables with a lot of triboelectric
noise. You don't get something for nothing.

Capacitance per foot is my #1 priority. It's to minimize shifts of tone
when playing my guitar with passive pickups, not an active circuit.
(Usually I play with the active circuit turned on, to minimize effects of
cable capacitance, but sometimes I like to switch to the passive sound.)

What you want, then, is a scope probe cable. This is a cable with a fairly
stiff plastic tube inside the braid, which loosely supports a very thin
center conductor. Characteristic Z is all over the place but shunt
capacitance is very low.

There is one of those cables in the Radio Guide... I think it might be
RG-416 but I won't guarantee it. Similar cables have been used for car
radio antennas and the high-Z playback heads for Ampex 300 and 350 recorders.
Easiest source, though, is probably to scrap an old Tektronix scope probe.

The problem is that these cables will get damaged a LOT more easily than
a conventional guitar cable.

but some of
the low-triboelectric-noise cables from Belden actually make great
instrument cables.

I know a lot of people love Belden, but every time I've checked Belden's
products, I've come up with nothing better than the Mogami cable I'm
using, or what I was using before that (Carol #1300, which I can no
longer find sold by the foot, if at all.)

The Belden material I am thinking of is something like 9239. It's 44 pF
per foot, but it has a steel strength member that makes it very hard to
damage, and it uses a special dielectric and some carbon impregnation that
almost eliminates handling noise.

Specifically, what Belden cables did you have in mind? If they have any
mic or other cable with the right specs, I'd like to know about it. BTW,
I really don't care about toughness, as long as the cable has good
electrical specs. I'll be happy to coil it properly, and keep it from
being run over or stepped on.

See, I would consider toughness to be the number one priority, with
handling noise number two, and capacitance number three.

What I really want is something like Klotz instrument cable AC110 (22 pF/
ft) or maybe AC106 (29 pF/ft), but I haven't been able to find anyone who
sells it by the foot. (I don't have much use for 100 meters of guitar
cables!)

Buy a big roll... make cables for your friends, use it for unbalanced audio
lines of all sorts. I'll occasionally buy a large order of something if I
need it... I always find some use for the rest of it although sometimes it
has taken twenty years....
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[WillStG]

On Jun 11, 10:15*am, (Scott Dorsey) wrote:
Buy a big roll... make cables for your friends, use it for unbalanced audio
lines of all sorts. *I'll occasionally buy a large order of something if I
need it... I always find some use for the rest of it although sometimes it
has taken twenty years....
--scott

I have a spray can of Finger Ease and a quarter roll of Radio Shack
Copper speaker wire older than that.

Will Miho
NY TV/Audio Post/Music/Live Sound Guy
"The large print giveth and the small print taketh away..." Tom Waits

[Jay Ts]

Mike Rivers wrote:
Jay Ts wrote:

Capacitance per foot is my #1 priority. It's to minimize shifts of tone
when playing my guitar with passive pickups, not an active circuit.
(Usually I play with the active circuit turned on, to minimize effects
of cable capacitance, but sometimes I like to switch to the passive
sound.)

For anyone who didn't understand that, go read this:
http://www.buildyourguitar.com/resou...emme/index.htm

If you don't have time or it's too technical, just skip to the bottom
and look at figure 15.

Also, look at Figure 16. He calls this an "inferior" pickup, but to me
(with my engineer's hat on - I don't have an electric guitarist's
hat), it looks like with what's a fairly typical amplifier load,

Your engineer's amp, or a guitar amp? The vintage guitar amp
shematics I've seen typically have very high input impedances (like 500K
or 1Mohm). I assume this is to preserve the resonant peak of passive
pickups.

it's pretty good - no resonant peak to
tame, and a gentle rolloff down to about 3.5 or 4 kHz.

I was surprised to learn that I was better off without a resonant peak,
because the resonant frequency of a pickup is said (by pickup
manufacturers!) to be one of most important pickup characteristics.

I've tried reducing the resistance across the pickup below what is
required to reduce the peak, and I really didn't like the result.
The guitar sounded dead and lossy. But, other people might like that,
and maybe the effect could be useful for some things.

We'd have to get that "inferior pickup" in a guitar and listen to it to
really understand what it sounds like.

The author was using it as an example of a pickup with strong eddy
currents, which he thinks is a poor design. The frequency response chart
doesn't tell everything.

It really depends on whether your preferred sound can take advantage of
a resonant peak to bring out what's there above 3 kHz, or whether it
gets in the way either as harshness or noise. I can see that if you want
that high end boost and increase the capacitive load, while you
can move the peak around a bit, the greatest effect will be to
increase the high frequency rolloff.

Yes, very right.

The author of that article has something to sell.

Yes, obviously. And it's good to keep that in mind when he's calling a
pickup with no resonant peak "inferior". His product that is a rotary
switch with capacitors won't do much on that pickup.

What I really want is something like Klotz instrument cable AC110 (22
pF/ ft) or maybe AC106 (29 pF/ft), but I haven't been able to find
anyone who sells it by the foot. (I don't have much use for 100 meters
of guitar cables!)

You could do what others do - build and sell expensive cables. After the
first 20 or 30 sales, you'll have paid for your own set of cables,
and then when someone on line poo-poos your cables as being filled
with snake oil, you can stop advertising.

I know, I know ...

Run the numbers. What's the difference in frequency response between
your pickup with an extra 400 pF across it (the difference between 30
and 50 pF/ft for a 20 foot cable)? And more important, is it
sonically significant?

Yes. The cable I'm using daily is actually about 410 pF (10 feet of
Mogami 2425 plus 2 Neutrik phone plugs), and I can hear the effect of the
cable. It was easier to hear before I reduced the resonant peak. Now
there is less difference between active and passive sounds, but there is
still a difference.

In a a listening test it can be difficult to tell the difference between
two similar cables, because of the seconds of quiet time while unplugging
one cable and plugging in the other (on both ends) ... along with other
variables, such as playing style. But when I made a test circuit and
could switch between capacitors of different values quickly for an A/B
comparison, 400 pF made an obvious difference. I was quite surprised at
how obvious! I was asking myself if I could tell the difference between
47 pF and 100 pF. I wasn't so sure in that range.

Look at Lemme's chart again. With his 1972 Fender Stratocaster pickup,
switching from a 47 pF capacitor to a 470 pF capacitor changed the
resonant frequency from about 8 KHz to about 4.5 KHz. And going from
there to 1000 pF took the peak down to around 3.2 KHz. The peak is about
12 dB high! Think of it this way: if you were doing that with a bandpass
filter combined with a -12 dB/octave lowpass filter, wouldn't you notice
the difference?

I think there are reasons why some guitarists do not notice the effect of
different guitar cables. For example, common guitar speaker cabinets (say
a 2x12 cabinet) may have response to just 5 KHz. But if you are listening
to a guitar through higher fidelity equipment, it's easier to hear.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

[Jay Ts]

Scott Dorsey wrote:
Capacitance per foot is my #1 priority.

What you want, then, is a scope probe cable.

Scott, thanks for this idea.

This is a cable with a
fairly stiff plastic tube inside the braid, which loosely supports a
very thin center conductor. Characteristic Z is all over the place but
shunt capacitance is very low.

There is one of those cables in the Radio Guide... I think it might be
RG-416 but I won't guarantee it. Similar cables have been used for car
radio antennas and the high-Z playback heads for Ampex 300 and 350
recorders. Easiest source, though, is probably to scrap an old Tektronix
scope probe.

Ok, well, after the recent discussion here of PC oscilloscopes vs.
traditional ones, I picked up a Tektronix 2232 DSO from an eBay seller,
and it came with a couple of old Tek scope probes (P6108), which I
quickly replaced with new ones. The cables are actually not stiff, but
are more flexible than typical guitar cables.

I measured the capacitance of one, and it's just 42 pF, total (7 pF/ft).
Nice. On the other hand, I measured a DC resistance of the center
conductor of about 260 ohms. This is off the scale in comparison to any
other (non-broken) guitar cable, and I'm going to have to think about it
before deciding that it's ok to use as a guitar cable.

These scope probes are in really bad condition, and are only 6 feet long,
so I don't think I'll try using them as guitar cables other than as a
quick proof-of-concept test. But maybe I'll go shopping for cable such as
the ones used for this, and Belden or some other company might make
something I can use.

The problem is that these cables will get damaged a LOT more easily than
a conventional guitar cable.

I would assume so, but thanks for the warning anyway.

See, I would consider toughness to be the number one priority, with
handling noise number two, and capacitance number three.

Yes, I understand. For many applications, that's very reasonable.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

[Richard Crowley]

"Jay Ts" wrote ...
I measured the capacitance of one, and it's just 42 pF, total (7 pF/ft).
Nice. On the other hand, I measured a DC resistance of the center
conductor of about 260 ohms. This is off the scale in comparison to any
other (non-broken) guitar cable, and I'm going to have to think about it
before deciding that it's ok to use as a guitar cable.

The whole reason for needing low-capacitance is because the
impedance is so high. What difference is 260 ohms (or even 1 K
or 5K) series resistance going to make at those kinds of very high
impedances?

[Scott Dorsey]

Jay Ts wrote:

I measured the capacitance of one, and it's just 42 pF, total (7 pF/ft).
Nice. On the other hand, I measured a DC resistance of the center
conductor of about 260 ohms. This is off the scale in comparison to any
other (non-broken) guitar cable, and I'm going to have to think about it
before deciding that it's ok to use as a guitar cable.

Series resistance is just fine. You got a 1M ohm input resistance...
a measly 260 ohms is so low in comparison it will hardly make a
measurable difference.

These scope probes are in really bad condition, and are only 6 feet long,
so I don't think I'll try using them as guitar cables other than as a
quick proof-of-concept test. But maybe I'll go shopping for cable such as
the ones used for this, and Belden or some other company might make
something I can use.

Belden doesn't make a similar "loose tube" cable.... but complain to
Steve Lampen and suggest that he start making it. I don't have a good
source for long runs of it.... I was actually looking for a couple hundred
feet at one point for a VLF antenna that was a sub-wavelength stub.

The problem is that these cables will get damaged a LOT more easily than
a conventional guitar cable.

I would assume so, but thanks for the warning anyway.

See, I would consider toughness to be the number one priority, with
handling noise number two, and capacitance number three.

Yes, I understand. For many applications, that's very reasonable.

Every festival I work, we have at least one musician a day with a bad
cable. At the East Coast Jazz Festival, we had one bass player come in
with a bad cable two years in a row. Might have been the same bad cable.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Richard Crowley]

"Scott Dorsey" wrote ...
Every festival I work, we have at least one musician a day with a bad
cable. At the East Coast Jazz Festival, we had one bass player come in
with a bad cable two years in a row. Might have been the same bad cable.

My favorite double-bass story (not necessarily aprocryphal)...
So the village musicians have assembled again to do their annual
performance of Messiah. As usual, the double-bass player barely
gets his instrument and bow ready as the conductor is about to
give the downbeat.

The conductor stops and yells: "Fred, don't you want to tune first?"
Fred replies: "Why? Isn't it in the same key as last year?"
rimshot

Actually observed at the Civic Auditorium in Portland when Peter
Schickele came to do his "play-by-play" during the first movement
of the Beethoven 5th:

As they were playing along (between other stunts) suddenly there is
a loud groan from the double-bass section, and Bill Walters (Peter's
stage manager dressed as a referee) runs in, blows his whistle, and
stops the play.

Shickele says: "Oh, there's annother of those groin injuries in the bass
section. That is bound to happen when they put them so close together."
At that point two EMTs in white uniforms from the local ambulance
service run in with a stretcher and haul the player off the stage. They
immediately return and put his instrument on the same stretcher and
whisk it off stage as well.

Shortly, an electric bass player wearing the black leather jacket from
a popular local rock band shows up with his instrument in one hand
and a small amp in the other hand. At the sight of him, all the other
bass players show varying signs of doubt, distain and disgust. He
walks into the section and says loudly "hey, where can I plug in my
amp?" To his credit he plays the rest of the movement quite well.

[Mike Rivers]

Jay Ts wrote:

Your engineer's amp, or a guitar amp? The vintage guitar amp
shematics I've seen typically have very high input impedances (like 500K
or 1Mohm). I assume this is to preserve the resonant peak of passive
pickups.

I think it's to not let the inductance of the pickup act as a high-cut
filter.

I was surprised to learn that I was better off without a resonant peak,
because the resonant frequency of a pickup is said (by pickup
manufacturers!) to be one of most important pickup characteristics.

It may be one of a given pickup's most important characteristics, but
this is like calling a bug a feature. There just isn't much coming from
a guitar string in the range of that peak, and it probably creates some
phase oddities between the overtones. This may be what gives
the pickup a certain characteristic sound. Honestly, before this
discussion I never knew that pickups had a resonant peak in the
audio range. But as an engineer, I'd rather do without it. As a
guitarist, apparently you would, too.

I've tried reducing the resistance across the pickup below what is
required to reduce the peak, and I really didn't like the result.
The guitar sounded dead and lossy. But, other people might like that,
and maybe the effect could be useful for some things.

The typical tone control on a guitar consists of a capacitor in series
with a variable resistor, shunted across the pickup.

We'd have to get that "inferior pickup" in a guitar and listen to it to
really understand what it sounds like.

It might be inferior because of the magnetic structure, not the lack
of a resonant peak.

The author was using it as an example of a pickup with strong eddy
currents, which he thinks is a poor design. The frequency response chart
doesn't tell everything.

Exactlyl.

Yes. The cable I'm using daily is actually about 410 pF (10 feet of
Mogami 2425 plus 2 Neutrik phone plugs), and I can hear the effect of the
cable. It was easier to hear before I reduced the resonant peak.

Can you describe what you're hearing? Just because you can hear a
difference doesn't make it bad, only if it sounds worse with one cable
than another. Or worse with a long cable than a short one. And is this
difference something that you can't compensate for with a little tweak
of the tone controls on the amplifier? You may be worrying about
something that's really trivial.

In a a listening test it can be difficult to tell the difference between
two similar cables, because of the seconds of quiet time while unplugging
one cable and plugging in the other (on both ends) ... along with other
variables, such as playing style.

This is why I say your concerns may be strictly academic. There's no
reason not to do some research, but you need to decide whether the
different matters. Will it run the song one way or the other?

But when I made a test circuit and
could switch between capacitors of different values quickly for an A/B
comparison, 400 pF made an obvious difference.

I'm not surprised. But you have to connect the guitar to the amplifier with
SOMETHING. Perhaps the best solution for you is to make or buy a
buffer that presents a high impedance (and low capacitance) to the pickup
and a low impedance to the outside world. This what active electronics in
a guitar does, but it may do other things and that's why you don't
always prefer the sound of your guitar with the active circuit. You need
a very flat and low distortion buffer with lots of dynamic range so you're
amplifying (and hence listening to) everything that comes out of the pickup.

Look at Lemme's chart again. With his 1972 Fender Stratocaster pickup,
switching from a 47 pF capacitor to a 470 pF capacitor changed the
resonant frequency from about 8 KHz to about 4.5 KHz. And going from
there to 1000 pF took the peak down to around 3.2 KHz.

Well, that's how an L-C parallel resonant circuit works.

I think there are reasons why some guitarists do not notice the effect of
different guitar cables. For example, common guitar speaker cabinets (say
a 2x12 cabinet) may have response to just 5 KHz. But if you are listening
to a guitar through higher fidelity equipment, it's easier to hear.

Well, like the doctor said, don't DO that.

--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Jay Ts]

Scott Dorsey wrote:
Jay Ts wrote:

I measured the capacitance of one, and it's just 42 pF, total (7 pF/ft).
Nice. On the other hand, I measured a DC resistance of the center
conductor of about 260 ohms. This is off the scale in comparison to any
other (non-broken) guitar cable, and I'm going to have to think about it
before deciding that it's ok to use as a guitar cable.

Series resistance is just fine. You got a 1M ohm input resistance...

I *may* have a 1M input resistance. Or I might have less. There is a wide
range of input impedances in equipment that is designed to be used with
guitars. I think it will be ok, because if I am using something with a
lower input resistance, I won't be plugging a passive pickup into it
anyway.

Still, one of my concerns is that I may try using the cables for other
things, where somehow, it may matter. I suppose that putting labels on
the cables, so that I remember that they're different, would be
sufficient.

But my greater concern isn't the input at the preamp, it's what's going
on inside the guitar. I just want to feel comfortable that the resistance
will not be a significant influence on the resonant peak of the RLC
guitar circuit, which includes the inductance of the pickup coil along
with its resistance and capacitance, along with whatever resistors and
capacitors I put across it (parallel) to intentionally modify the
resonant peak, and there's the volume control, and then the capacitance
and now resistance of the cable, along with any effect produced by the
input of the preamp that the cable is plugged into at the other end.

I admit, I'm not fully (really, even nearly) up to speed on understanding
RLC circuits, so please forgive me if I'm being slow.

I *think* that it is always true in RLC circuits, that the capacitance
(whether series or parallel) affects the resonant frequency, and
resistance (whether series or parallel) affects the Q, or in other words,
the height and width of the peak.

If that is true, then I only need worry about the Q of the circuit. But,
the DC resistance of the pickup -- I think -- is mostly what determines
that, and in some pickups that is as low as about 2.5 Kohms (and I don't
know about all pickups!). So I don't feel really safe yet. As I said,
understanding resonance in RLC circuits is still beyond me, so I don't
know if the resistance of the cable comes into play, or by how much.

I will probably need to run some Spice simulations, read some more about
RLC circuits, and play with some actual circuits before I am really clear
on this.

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

[Jay Ts]

Mike Rivers wrote:
Jay Ts wrote:

Your engineer's amp, or a guitar amp? The vintage guitar amp
s[c]hematics I've seen typically have very high input impedances
(like 500K or 1Mohm). I assume this is to preserve the resonant
peak of passive pickups.

I think it's to not let the inductance of the pickup act as a high-cut
filter.

It's my current understanding(?) that adding resistance in parallel with
the inductor affects only the Q of the resonant low-pass RLC circuit, not
the frequency.

I was surprised to learn that I was better off without a resonant peak,
because the resonant frequency of a pickup is said (by pickup
manufacturers!) to be one of most important pickup characteristics.

It may be one of a given pickup's most important characteristics, but
this is like calling a bug a feature. There just isn't much coming from
a guitar string in the range of that peak,

I disagree with that.

and it probably creates some
phase oddities between the overtones. This may be what gives the pickup
a certain characteristic sound. Honestly, before this discussion I never
knew that pickups had a resonant peak in the audio range.

Ok, well, here's something for you to study:

http://www.seymourduncan.com/comparetones

It lists the resonant frequencies of all of Seymour Duncan's pickups.
(Along with other specs.)

But as an engineer, I'd rather do without it.

If you heard the same thing in a condensor microphone, you'd be all over
it trying to equalize it out, or you'd just toss the mic in the trash ...
although many condensor mics have a little peak in frequency response
around 12 KHz, and some people call it "air" and think it's a feature,
not a bug. ;-)

As a guitarist, apparently you would, too.

In this case it seems to work better for me. But they make dobros and
other resonator guitars, and they're supposed to sound pretty special!
Having resonance in the electronics is just the "electric guitar" way of
doing it, I suppose.

While I was playing around with various values of capacitors, I got some
really cool sounds with the larger values. It's a very different sound
than you'd get from using a tone control.

I've started thinking of it more like this: analog synths have resonant
low-pass filters, and they are a huge part of the sound of the
instrument. I have a synth (E-mu Xtreme Lead 1) that allows the resonant
frequency to be shifted around in realtime using a controller knob. And
it can be a lot of fun. Synths are designed to maximize the effect, and
it's a lot more noticeable on a square wave with lots of high harmonics.

Maybe it's because I'm used to playing with my synth, but I was noticing
a similar effect while trying increasingly larger capacitors across my
pickup. So now I am thinking of guitar pickups as transducers with built-
in resonant low-pass filters. It's not as "in your face" as with a
synthesizer, but IMO it's creatively useful.

Yes. The cable I'm using daily is actually about 410 pF (10 feet of
Mogami 2425 plus 2 Neutrik phone plugs), and I can hear the effect of
the cable. It was easier to hear before I reduced the resonant peak.

Can you describe what you're hearing?

OMG. If I knew this would come up, I would have considered making
recordings, so you and others could just listen to it! But I'm really
busy, and I wasn't thinking about that. If I haven't already described it
well enough, I don't think adding more words will do any good.

Just because you can hear a
difference doesn't make it bad, only if it sounds worse with one cable
than another. Or worse with a long cable than a short one.

Right. Or maybe it will sound better -- to some people -- when using a
long cable, because it depends on where the resonant peak ends up.
Depending on the total capacitance, the resonant frequency might land
somewhere nice, or not. I noticed this effect while trying different
capacitance values. And I have no idea if others would perceive the same
kind of thing or not.

But if that effect is real, it might explain why some guitarists think
that a particular cable is "magic".

Anyway, my goal is to have cables that have really low capacitance, so
the shift of the resonance is small, and hopefully, not significant.
I don't know any way to move the peak up in frequency, only down, so I
can't undo the effect of the cable later in the signal chain.

Also, I'd like to have the pickup resonance sound the same when I switch
back and forth from active to passive!

But when I made a test circuit and
could switch between capacitors of different values quickly for an A/B
comparison, 400 pF made an obvious difference.

I'm not surprised. But you have to connect the guitar to the amplifier
with SOMETHING. Perhaps the best solution for you is to make or buy a
buffer that presents a high impedance (and low capacitance) to the
pickup and a low impedance to the outside world.

That is exactly what I've been using in my guitars almost since Day One.
But every so often, I like to switch it off and play passive for a change
of pace. I just want that sound to be a good sound, not the muddy, icky
sound I've gotten in the past, which was a result of not knowing what I
was doing, and getting "whatever"!

Jay Ts
--
To contact me, use this web page:
http://www.jayts.com/contact.php

[Don Pearce[_3_]]

On 12 Jun 2009 04:59:15 GMT, Jay Ts
wrote:

and it probably creates some
phase oddities between the overtones. This may be what gives the pickup
a certain characteristic sound. Honestly, before this discussion I never
knew that pickups had a resonant peak in the audio range.

Ok, well, here's something for you to study:

http://www.seymourduncan.com/comparetones

It lists the resonant frequencies of all of Seymour Duncan's pickups.
(Along with other specs.)

There is a youtube interview with Seymour Duncan. He is talking about
the time he had to repair Blackie - Eric Clapton's "Layla" Strat. He
changed the volume pot, following which Clapton told him the tone had
changed - gone too bright. Duncan, being the careful chap he is, had
kept the parts he changed, and comparing pots, he found that although
both were nominally 250k, the new one was actually about 280k. He
found one much closer to spec, put it in and all was well again with
Blackie.

d

[Mike Rivers]

Jay Ts wrote:

I *may* have a 1M input resistance. Or I might have less.

You can measure it easily.

Still, one of my concerns is that I may try using the cables for other
things, where somehow, it may matter. I suppose that putting labels on
the cables, so that I remember that they're different, would be
sufficient.

Why not just pack the guitar cables with your guitar?

But my greater concern isn't the input at the preamp, it's what's going
on inside the guitar. I just want to feel comfortable that the resistance
will not be a significant influence on the resonant peak of the RLC
guitar circuit

So, listen. Pick out a cable that you like. As discussed, you may LIKE
the sound of the guitar with the resonant peak moved to a different place,
or smoothed out. But you can't make that judgment by comparing A to B and
saying "I can hear a change so it must not be good." You have to decide
how you want the guitar to sound and if you can get that sound by using
a specific cable, then so be it. Or maybe you'll want to run your guitar
through a box with a switched collection of capacitors and resistors to
customize the load (and a buffer on the output so it'll work the same
into any input).

But then, until you have established your system with your sound (which
may involve more than one amplifier) you'll need to consider whether the
differences between one amplifier and another, even if you were to isolate
the pickup from the input impedance of the amplifier, are more significant
than the differences between cables.

I *think* that it is always true in RLC circuits, that the capacitance
(whether series or parallel) affects the resonant frequency, and
resistance (whether series or parallel) affects the Q, or in other words,
the height and width of the peak.

The resonant frequency is determined by L and C. The shape of the peak
is determined by parallel resistance. But the resistance can also act,
along
with the inductance and capacitance, as a filter - not one with a resonant
peak, but one which will have a 6 dB per octave slope. So to fully
characterize
a circuit, you need to consider all of the filter circuit paths. To make
design
and understanding easier, we make assumptions that this effect will be
enough greater than that effect within the range of frequencies of interest
so that we can ignore the lesser one. But our ears can be more revealing
than our calculations or electrical measurements.

I'll give the guy whose web page you're studying credit for attempting to
use measurements to explain what he hears. That's the right thing to do.
But I don't know whether he's measuring the right thing, or all of the
things
he should be measuring.

If that is true, then I only need worry about the Q of the circuit. But,
the DC resistance of the pickup -- I think -- is mostly what determines
that

The DC resistance of the load, since it's directly in parallel with the
resonant
circuit, is also significant. In designing guitar amplifiers, we
(usually) try to
make this as high as possible so that it has minimal effect on the pickup.
But if what we want is to make the circuit closer to being critically
damped
(no significant resonant peak, and smooth rolloff beyond the resonant
frequency), we may want to use a lower load impedance.

In practice, I suspect, the resonant peak extends the high frequency
output of the pickup, boosting what's pretty weak coming off the string
(or magnet assembly). This is why the usual reaction to too low a load
impedance on a pickup is that it makes the guitar sound dull - and that
what we want is a frequency response that is NOT flat. But this is
something for guitarists and guitar designers to argue about. We can
make the electronics work any way they want it to work.

I will probably need to run some Spice simulations, read some more about
RLC circuits, and play with some actual circuits before I am really clear
on this.

First, listen when you're playing. Try to quantify what you're hearing.

--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)