#1
i know the jcm 900 has diode clipping but is it in both channels or just channel b? i looked up the schematics but i have no idea how to interpret them. does anyone have any knowledge on this?
#2
Does it honestly matter? If it sounds good, use it.

╠═══════╬═══════╣

THE SINE WAVE SURFER σƒ τλε τρπ βπστλεπλσσδ

╠═══════╬═══════╣


[quote="'[BurnTheDusk"]']Boss pedals may be built like tanks but I would rather buy a cardboard box that is on my side than pay for a tank that is working against me.
#3
Quote by Dr.Pain-MD
Does it honestly matter? If it sounds good, use it.


i completely agree with you but is curiosity a crime?
Last edited by no_thing101 at Jul 5, 2009,
#4
Definetly not. I'm glad you're not one of the people who automatically dismisses something if it has diodes in it. My guess is that the clipping would only be used for the distortion channel (I am assuming you're talking about the Dual Reverb) and thus the diodes would only be active on Channel B.
EDIT: That is because a clean signal does not need to be clipped (the purpose of the diodes is clipping).

╠═══════╬═══════╣

THE SINE WAVE SURFER σƒ τλε τρπ βπστλεπλσσδ

╠═══════╬═══════╣


[quote="'[BurnTheDusk"]']Boss pedals may be built like tanks but I would rather buy a cardboard box that is on my side than pay for a tank that is working against me.
#5
Quote by Dr.Pain-MD
Definetly not. I'm glad you're not one of the people who automatically dismisses something if it has diodes in it. My guess is that the clipping would only be used for the distortion channel (I am assuming you're talking about the Dual Reverb) and thus the diodes would only be active on Channel B.
EDIT: That is because a clean signal does not need to be clipped (the purpose of the diodes is clipping).


well channel A isnt a clean channel. it is the cleanER channel. i can still dish up some gain (but not much). it sounds warmer and has more volume so i was wondering if that is because it has no diode clipping.
#6
Ah. In that case I'm guessing it just either bypasses a gain stage or maybe has a different tonestack because if it still clips I doubt that they would take the diodes out.

╠═══════╬═══════╣

THE SINE WAVE SURFER σƒ τλε τρπ βπστλεπλσσδ

╠═══════╬═══════╣


[quote="'[BurnTheDusk"]']Boss pedals may be built like tanks but I would rather buy a cardboard box that is on my side than pay for a tank that is working against me.
#7
I'm pretty sure the 'gain sensitivty' control is the main one for adding diode clipping.

I agree that the 900 gets a lot of flak for it's diode clipping, which is strange considering how many players use a Tubescreamer or DS-1 in front of their JCM800s....
#8
Quote by kyle62
I'm pretty sure the 'gain sensitivty' control is the main one for adding diode clipping.

I agree that the 900 gets a lot of flak for it's diode clipping, which is strange considering how many players use a Tubescreamer or DS-1 in front of their JCM800s....


i forgot to mention that i am talking about the dual reverb version (which doesnt have the sensitivity knob)

here are the schematics. is there anyone that can read them?


Last edited by no_thing101 at Jul 5, 2009,
#9
Quote by kyle62
I'm pretty sure the 'gain sensitivty' control is the main one for adding diode clipping.

I agree that the 900 gets a lot of flak for it's diode clipping, which is strange considering how many players use a Tubescreamer or DS-1 in front of their JCM800s....

i personally like the 900 better then the 800. i have two clips on my profile. take it away is played with an 800 and mind your head on a 900. both with a les paul and both with nothing in front of the amp. the tone of the 900 is far and away the winner between those two recordings.

EDIT: on topic, i have no idea about what goes on inside those things and the schematics are beyond my circuit knowledge.
Last edited by joe_k at Jul 5, 2009,
#10
Ask in the Gear Building and Customizing, kurtlives91 should probably know, or at least be able to work out that from the schematic.
#11
Quote by Goldenglove
Ask in the Gear Building and Customizing, kurtlives91 should probably know, or at least be able to work out that from the schematic.


done and thanks for the suggestion.
#12
Remember, not all JCM 900's have diodes in the preamp.

JCM900 Models 2500, 2501, 2502 & 2100, 2101 (non SLX) do use a diode bridge for clipping and are not SLX models which did not begin production until 1993.

JCM900 Models 2100SLX & 2500SLX do not use diode clipping at all and instead use additional tube gain stages. Its easily identified with its complement of 5 pre-amp tubes which includes the PI.
MARSHALL JVM 210H
PEAVEY JSX
KRANK 412
MESA 412
FENDER STRATS
DIMARZIO
CELESTION