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From: TerryKing on 15 Apr 2010 04:19
>Say, do people remove the volume (and tone) pots? They seem to be useless.

High-end (used to be custom-only) guitars put the preamp/conversion IN
the guitar. If you have a pot panel that's removable you're golden.
Else it's like arthroscopic surgery.

All the previously-mentioned detractors like noise from pots,
connectors, cable capacitances etc. are avoided.

Some my recording-engineer friend talked about had both magnetic
pickups and microphones in the same guitar.

Low Noise would be great for classical guitar. But a LOT of the
guitar noises that make money are "Down in the noise level" anyway :-)

Usually the big problem is the darn cables, hum pickup, ground loops
etc, external to the guitar. My friend has installed 120VAC "Balanced
to ground" power in his professional studio, which greatly reduces
60Hz pickup in lots of places. And a common-point ground/neutral
connection to a 6 inch wide copper strap that runs through the floor
slab and stubs up in the equipment locations. Recently this approach
is even IN the Electrical Code. Previously, he was fortunate in that
he was in remote Vermont, 100 miles from the nearest electrical
inspector...

24 bits might be 'excessive', but "Moderation In the Pursuit Of Clean
Signals is Not a Virtue". (Was that Barry Goldwater??)


From: whygee on 15 Apr 2010 04:39
TerryKing wrote:
>> Say, do people remove the volume (and tone) pots? They seem to be useless.
>
> High-end (used to be custom-only) guitars put the preamp/conversion IN
> the guitar.

I use to remove all knobs from my guitars,
I see no point in having TWO volume controls in series
(one in the guitar, the other in the amp).
I don't use amps anyway.
Oh, and the "tone" knobs are also removed,
I love the bare sounds of each guitar.
My idea is that any sound alteration should be left to
post-production, after the sound has been recorded...

As a side effect, the removed knobs leave a few holes
in the guitar's body, where there is a little void,
that then acts as a resonant chamber.
So I have an old SANOX guitar that sounds
good with AND without amplification,
depending on the strings' quality.
With this model, the guitar is more versatile
without knobs than the original version...

yg
--
http://ygdes.com / http://yasep.org
From: Colin Howarth on 15 Apr 2010 07:23
In article
<15cbedf8-8ec6-4d36-9109-6c8a3ee78fc9(a)g11g2000yqe.googlegroups.com>,
TerryKing <terry(a)terryking.us> wrote:

> >Say, do people remove the volume (and tone) pots? They seem to be useless.
>
> High-end (used to be custom-only) guitars put the preamp/conversion IN
> the guitar. If you have a pot panel that's removable you're golden.
> Else it's like arthroscopic surgery.


Oh. I'm good at that. :-) I'd put switches where the pots are to change
between series and parallel wiring of the humbuckers for example.


> All the previously-mentioned detractors like noise from pots,
> connectors, cable capacitances etc. are avoided.


Sounds good.


> Some my recording-engineer friend talked about had both magnetic
> pickups and microphones in the same guitar.
>
> Low Noise would be great for classical guitar. But a LOT of the
> guitar noises that make money are "Down in the noise level" anyway :-)
>
> Usually the big problem is the darn cables, hum pickup, ground loops
> etc, external to the guitar. My friend has installed 120VAC "Balanced
> to ground" power in his professional studio, which greatly reduces
> 60Hz pickup in lots of places. And a common-point ground/neutral
> connection to a 6 inch wide copper strap that runs through the floor
> slab and stubs up in the equipment locations. Recently this approach
> is even IN the Electrical Code. Previously, he was fortunate in that
> he was in remote Vermont, 100 miles from the nearest electrical
> inspector...


I don't have a problem until I connect my MacBook Pro to mains...


> 24 bits might be 'excessive', but "Moderation In the Pursuit Of Clean
> Signals is Not a Virtue". (Was that Barry Goldwater??)


:-)
From: Ralph Barone on 15 Apr 2010 09:51
In article <colin-685382.12213914042010(a)free.teranews.com>,
Colin Howarth <colin(a)howarth.de> wrote:

> In article <82khg3Fc4vU1(a)mid.individual.net>,
> "Phil Allison" <phil_a(a)tpg.com.au> wrote:
>
> > "Paul Keinanen"
> >
> > > In order to avoid noise and hum problems, I would definitively want to
> > > build the amplifier into the guitar,
> >
> > ** Why ?
> >
> > Don't you believe that a few metres of well shielded co-axial cable can
> > deliver the signal from a guitar PU without introducing hum or noise ?
> >
> > It's the guitar's PUs ( and any unshielded internal wiring) that are
> > sensitive to electric and magnetic hum fields, not the connecting cable.
>
>
> Perhaps Paul (and certainly I) are a victim of that
>
> A little learning is a dangerous thing; drink deep, or taste not the
> Pierian spring: there shallow draughts intoxicate the brain, and
> drinking largely sobers us again.
>
> thing. :-)
>
>
> I'm surprised no-one has yet said "what's this obsession with low noise?
> An E-guitar isn't a Stradivarius!"
>
> The whole issue is (or I'm making it) a bit more complicated than it may
> seem.
>
>
> Pro audio (not that I'm a pro) is mostly digital these days. My digital
> audio workstation (aka computer) likes 192 kHz 24bit input. That may
> seem like overkill considering that I don't even hear up to 20 kHz
> anymore BUT...
>
> Guitar pickups (resistive/inductive) in combination with cable
> capacitance have their own resonance, distortion and filtering
> characteristics (ie. sound) and, in the old days, these even change
> depending on what effects boxes you plug into, due to varying load
> impedance.
>
> However, now, ALL the signal modification (including filtering and
> distortion) is supposed to be going on in the computer using amp
> modelling, equalisation, artificial distortion etc.
>
>
> If I'm sampling 24 bits, I'd like the input signal to be as clean as
> possible. The ADC wants 5.6 Vpp (full scale). That's differential input,
> so each signal is supposed to be 2.8 Vpp, ie. around 1 V rms.
>
> The pickups output around 300 mV rms.
>
> 1 bit of that is, ummmm, about 18 nV.
>
> -> low noise amps, pre-amp as soon as possible.
>
>
> --colin

Plug your guitar into a scope and whack the hell out of the strings.
You might be surprised what sort of peak voltages you can get.
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