Welcome, Guest. Please login or register.
Did you miss your activation email?
November 23, 2024, 05:07:39 AM
Home Help Search Login Register
News: Ceriatone Forums are up and running!!!
 
Guests please register
Note: If you want to help you can donate to keep the forums alive.



Do you want to advertise on this forum ? Send me a private message.



Amplified Parts
+  Ceriatone Forum
|-+  British Style
| |-+  JCM 800 2203, 2204, 2550, 2555
| | |-+  JCM 800 2204 - JMP 2204 QUESTION
« previous next »
Pages: [1] Go Down Print
Author Topic: JCM 800 2204 - JMP 2204 QUESTION  (Read 8181 times)
hotguit
Newbie
*
Offline Offline

Posts: 4


View Profile
« on: August 27, 2009, 04:03:16 PM »

Hi
I've noticed that in my 1985 JCM 800 2204 (horizzontal inputs) there are two 10K 1 W res. while in my 1978 JMP 2204 only one (the circuit is the same, one with pcb mounted pots, the other with chasis mounted pots) SEE PICTURE
Why? how does it affect the tone?
Is it a good idea remove it and put a jumper (on jcm 800?)
thank you
hot


* CERIATONE 2204 1.JPG (219.16 KB, 1348x890 - viewed 1062 times.)
Logged
cmoore
Sr. Member
****
Offline Offline

Gender: Male
Posts: 351


View Profile
« Reply #1 on: August 27, 2009, 07:38:54 PM »

Does one amp have a choke, and the other does not?
Logged
hotguit
Newbie
*
Offline Offline

Posts: 4


View Profile
« Reply #2 on: August 28, 2009, 08:58:23 AM »

both have choke.
Same circuit, different layout
hot
Logged
DanLurie
Newbie
*
Offline Offline

Posts: 2


View Profile
« Reply #3 on: September 15, 2009, 10:28:40 AM »

It's an extra decoupled stage in the high voltage line. It provides more filtering to the preamp.  I believe it's part of the original circuit. The filtering is a good thing in a higher gain amplifier. No need to jump it.

How do the two amps compare in sound??
Logged
hotguit
Newbie
*
Offline Offline

Posts: 4


View Profile
« Reply #4 on: October 15, 2009, 01:41:17 PM »

jmp has a warmer and creamier tone and starts overdriving at about 12 o clock (preamp pot)
jcm is harsher and les compressed; it starts overdriving at about 14 o clock
bye
hot
Logged
Kitarist
Administrator
Sr. Member
*****
Offline Offline

Gender: Male
Posts: 253


View Profile
« Reply #5 on: October 18, 2009, 11:33:25 PM »

What kind of mod do you need to do to transform a JCM into a JMP?

Thanks!!!
Logged

Music has to breathe and sweat. You have to play it live
Pages: [1] Go Up Print 
« previous next »
Jump to:  


Login with username, password and session length

Powered by MySQL Powered by PHP Powered by SMF 1.1.12 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!

CeriaTone Forum is not afiliated with Ceriatone Amplifications. The CeriaTone and name, logo and related trademarks and service marks, owned by CeriaTone. , are registered and/or used in the U.S. and many foreign countries. All other trademarks, service marks, and trade names referenced in this site are the property of their respective owners.