Newsgroup: it.arti.musica.strumenti.chitarra
Titolo: Marshall: all valve head? in inglese e pure lungo.

Non mi ricordo chi, perchè come al solito faccio casino con i nomi e i
post, mi chiedeva maggiori info sul fatto che i Marshall siano o meno all
valve head, in particolare la serie jubilee. Bene, qui c'è la risposta!
Grazie a Peps che mi ha postato il messaggio, anche se poi ha letto solo
le prime 2 righe, ritendendosi d'accordo e soddisfatto!
Early JCM-800's with diode clipping
By the early 1980's, Marshall was producing amps that mixed tube and
transistor distortion. The transistor distortion was accomplished by
adding "diode clipping" circuits among the tube preamp gain stages, which
gave the amps a lot more distortion, but sacrificed warmth. The tubes
before the diodes helped to push guitar signal into the diodes, where they
were clipped (distorted), and the tubes after the diodes both amplified
and "warmed up" the sound somewhat. These and later Marshalls had a
bright, buzzy distortion, especially at low volumes. When cranked up loud,
the power tubes would begin distorting, thickening up the sound to reduce
the harsh, thin, buzzy distortion. Another unsual (for Marshall) feature
was that the EQ was positioned early in the preamp, just after the first
gain stage. This would be changed on later JCM-800 models: moved to after
3 gain stages, just like on the 2203 amps. And the new 4210/2205 amps
sported (had) an effects loop, something new for Marshall. This allowed
guitarists to put their delay pedals after the preamp distortion for
cleaner delays. Finally, Marshall used a post phase inverter master volume
for these amps. Marshall would later change back to a master volume after
the EQ (but before the phase inverter) much like the 2203 amps. 
Some metal players loved these new Marshalls, whereas many older rock and
blues players hated them. 
The 1980's marked a confusing period for Marshall, as they were
simultaneously still making 1. non-master volume amps: circuits 1987 (50
watt model) and 1959 (100 watt model), 2. 1970's style Master volumes
(circuit 2203-all tube signal path), and 3. the new models with tubes and
transistor distortion mixed, like the 50 watt 4210. 
Many players call all 2203 style master volumes JCM-800's, but these 2203
amps were being made long *before* Marshall began calling their amps
JCM-800's. Also, there were JCM-800's being made which used diode
clipping, and thus were *not* the older style 2203 circuit. 
So, if you hear someone talking about a "JCM-800", he could mean an all
tube 2203 master volume circuit (first produced in the 1970's, and which
Marshall continued to make in the 1980's). Or he could be talking about
one of the newer circuits with diode clipping, first made in the 1980's.
You could ask him "What model number are you refering to?". Or "Are you
talking about the 2203 circuit with an all tube signal path, or the
circuits with the mix of diode clipping and tube distortion?" If he says
something stupid like "All JCM-800's are the 2203 circuit! No JCM-800's
have diode clipping!", then you can tell him he's full of shit. (i.e. he's
either lying or just plain ill-informed) You can say, "Marshall's 50 watt
combo (model 4210) and 50 watt head (model 2205) both use diode clipping.
Just look in the "History of Marshall" book. 
Marshall's later JCM-800's
Marshall modified the new design, and a 1988 schematic for the 2210 (head)
and 4211 (combo) amps show an extra tube gain stage after the diode
clipping. The diode clipping itself had been altered to a more complex
arrangement-more like a diode bridge rectifier, and the EQ was
repositioned to after the third gain stage. Much like the 2203 amps. 
For Marshall's 25th Anniversary, they came out with the Jubilee amps,
favored by Slash or Guns and Roses, and recently reissued as the "Slash"
amps. These are among the most popular JCM-800 amps, which is somewhat
ironic, as they probably have to greatest use of diode clipping. Which at
low volume, to my ears, makes the amps sound too trebley. When cranked,
however, they can get an aggressive, yet warm tone. 
Marshall's JCM-900 amps continued to rely on pretty much the same formula
as the later JCM-800's. There were lots of differences (some of which
added gain), but the basic style remained the same: two gain stages in
series, diode clipping, third gain stage and EQ and master volume. Some
JCM-900 amps used IC's (transistor opamps) for additional gain. Some claim
that Marshall began using lower quality components in these JCM-900's,
which reduced reliabity. I've heard complaints that the output transformer
blows up more easily at high volumes than the output transformers used in
earlier Marshall amps. 
Marshall designed these amps with the late 1980's metal players in mind,
so they have a lot of gain and thin, buzzy transistor clipping mixed in
with the tubes.
Borgiaz           
A grande richiesta, la signature con caratteri standard!  
 
           (.) (.)
            )   (
           (  @  )
 
 

            (  @  )
ecco, vedi ad esempio,
dalle prime due righe della tua signature capisco che è una brutta gnocca!
ziopeps

dalle prime due righe della tua signature capisco che č una brutta gnocca!
MA SE SONO MODELLATE SU TUE SPECIFICHE!!!
(confronta la vecchia versione he he he !)
Borgiaz

Borgiaz <bor...@NOSPAMlibero.it> wrote in message
3971fe45...@news.infinito.it...

no no no no
 le mie specifiche sono le seguenti:
( . ) ( . )
c'č la sua bella differenza!;-)

 c'è la sua bella differenza!;-)
Beh......non ti si puo' certo dare torto !!!
;-)))
ciao
ale

vedo che il mio post in inglese ha riscosso grandi consensi !

>vedo che il mio post in inglese ha riscosso grandi consensi !
Hai soltanto avuto culo, amico :)
Fr@nK 
NEW! Ora disponibile anche su ICQ# 75893128 !!
*Ho conosciuto mia moglie perche' entrambi andavamo con lo stesso
ragazzo* (David Bowie)
 

Hai soltanto avuto culo, amico :)
Beh, insomma...io speravo di fare incazzare qualcuno , di vedere lotte
furibonde sul fatto che i marshall sono solo dei paedalini da 100w ...
-- Borgiaz
 
   ICQ # 70428611
 

 furibonde sul fatto che i marshall sono solo dei paedalini da 100w ...
il tuo rack da soprammobile è stato promosso a sgabello per le mie stanche
natiche la prossima volta che ti vengo sentire suonare
ritieniti onorato!:-P
pepssssss