how reducing noise in guitar preamps?

[Kevin Aylward]

"Kevin Aylward"










** Obvious to anyone who is not mentally ill - like YOU are.






** Obvious to anyone who is not mentally ill - like YOU are.



** Shame about the ** 500 kohm** volume pot on most electric guitars
and the 1 Mohm resistor on the J-FET gate.

The high source impedance of the guitar PU does NOT attenuate their
thermal noise like a 5 k ohms resistor !!

DAMN SHAME what happens when the guitar's volume pot is turned down
slightly from its max position - instantly making the source
impedance very high and resistive ( 100 -200 kohms typical).

Kinda swamps the tiny noise contribution of a 4.7 k series resistor !!

I never have my volume pots at any setting other than full up. Its the
professional way to play. It keeps the S/N at its best. It shunts the 1M
input amplifier resister, keeps the signal at its highest level and it
reduces the effect of cable capacitance. I use a volume pedal in the
insert point of the amp. Guitar volumes are only for those that don't
know how to their equipment to best effect.

If you are using the internal distortion of an amp, guitar volumes are
simply useless. One needs to set the amount of distortion and volume
independently. You can only do this after the distortion stage.

Aylward is totally INSANE .

Standard ASININE performance for someone who has bi-polar disorder
and ASD.




** Not at all.




** Have built over 100 SS guitar amps (my own design & with J-FET
inputs) and serviced around 6000 valve and SS guitar amps over the
last 36 years.

Oh... build and repair...so you are a repair tech with delusions of
grandeur.

Seen, played and repaired most types of electric guitar too - Les
Pauls, SGs, Strats, Teles etc.





** Absolutely for sure.

Most electric guitar PUs in common use DO generate lots of buzz and
hum.

Again, I disagree. If the guitar is a modest distance away from the amp,
a decent humbucker does not pick up any significant hum. Sure, at very
high distortion gains, hum is magnified a lot, but so is the thermal and
shot noise.


Kevin Aylward B.Sc.
[email protected]
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

"There are none more ignorant and useless,than they that seek answers
on their knees, with their eyes closed"

 

[Kevin Aylward]

And after the guitar's 'volume' control ? What then ?

A good point, although I personally always have my guitar volume full up
so its only the 1M end to end impedance. I always use a volume pedal in
the insert point of my amp...Which brings up another point. Those folks
at Marshal just don't seem to have it all together, and that's after 40+
years making amps. Their amps have a bloody parallel effects loop, so
you can't break the connection to insert a volume pedal. Indeed, even
phase peddles are useless because they rely on precise cancellation of
straight and delayed signal, oh.. and don't forget compressors equally
useless. I think they looked at a mixer, and just didn't understand what
and why it does what it does.

So, it was the back and forth emails to Paul Marshal, where upon I was
graciously sent the schematics so I could perform the relevant
modifications on my todd.

Kevin Aylward B.Sc.
[email protected]
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

"There are none more ignorant and useless,than they that seek answers
on their knees, with their eyes closed"

 

[Phil Allison]

"Kevin Aylward Fuckwit TROLL "

I never have my volume pots at any setting other than full up.

** Now the lying, POS is really desperate !!

Pretending HE is the topic.

Kevin Aylward is completely INSANE

Standard ASININE performance for someone who has both bi-polar disorder and
ASD.

Again, I disagree.

** Now the lying, POS is really desperate.

Pretending HE is the topic.

Kevin Aylward is totally INSANE .

Standard ASININE performance for someone who has both bi-polar disorder
and ASD.






........ Phil

 

[Eeyore]

Do tell, please show us a microphone preamp with 100 dB S/N. I may want to
have one.

It's not a microphone pre-amp.

Graham

 

[joseph2k]

The s/n of the pickup signal itself will depend hugely on the environment
due to the likely induction from stray magnetic fields and the like.

Acheiving ~ 100dB s/n from the elctronics is quite trivially simple
though.

Graham

Do tell, please show us a microphone preamp with 100 dB S/N. I may want to
have one.

 

[joseph2k]

"Kevin Aylward Fuckwit TROLL "




** Now the lying, POS is really desperate !!

Pretending HE is the topic.

Kevin Aylward is completely INSANE

Standard ASININE performance for someone who has both bi-polar disorder
and ASD.





** Now the lying, POS is really desperate.

Pretending HE is the topic.

Kevin Aylward is totally INSANE .

Standard ASININE performance for someone who has both bi-polar disorder
and ASD.






....... Phil

Get the h*ll of my internet you damned troll. Yes you Phil.

 

[Fred Bloggs]

Get the h*ll of my internet you damned troll. Yes you Phil.

*Your* internet?? Who the hell do you think you are?

 

[Frank Bemelman]

*Your* internet?? Who the hell do you think you are?

I suppose the first (or last, depending how you look at it) ten
meters UTP cable are mine

 

[Phil Allison]

"joseph2k"


Get the h*ll of my internet you damned troll. Yes you Phil.

JosephKK

Gegen dummheit kampfen die Gotter Selbst, vergebens.
--Schiller



** How come these criminal scumbags never got nuked like the Japs ??




........ Phil

 

[Michael A. Terrell]

"joseph2k"

Get the h*ll of my internet you damned troll. Yes you Phil.

JosephKK

Gegen dummheit kampfen die Gotter Selbst, vergebens.
--Schiller

** How come these criminal scumbags never got nuked like the Japs ??

....... Phil

Isn't your name on the top of that list, Phillis?


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida