scotteggshell
Member
- Joined
- Jan 28, 2009
- Messages
- 20
- Reaction score
- 0
I am trying to understand the Simulclass Power section in my MkIV, if someone has time could they help me out ?
By Looking at the diagram at :
http://www.schematicheaven.com/boogieamps/boogie_mkiv.pdf
Please tell me if I am wrong.
1) It appears to me that one set of tubes is run as Class A and the other in class AB.
2) The 220K(A) res on the screen of one set and the 2.2k(AB) on the other set are used to set the different bias points
3) To by controlling the values of the 220k res on point E you could lower the bias point of both tubes and keep the same difference between them(could I use a rheostat here ?). Thereby biasing one half of the amp with each trimmer
4) OR should the bias voltage be controlled at it's source and keep all 4 tubes ganged together.
Thanx
Scott
By Looking at the diagram at :
http://www.schematicheaven.com/boogieamps/boogie_mkiv.pdf
Please tell me if I am wrong.
1) It appears to me that one set of tubes is run as Class A and the other in class AB.
2) The 220K(A) res on the screen of one set and the 2.2k(AB) on the other set are used to set the different bias points
3) To by controlling the values of the 220k res on point E you could lower the bias point of both tubes and keep the same difference between them(could I use a rheostat here ?). Thereby biasing one half of the amp with each trimmer
4) OR should the bias voltage be controlled at it's source and keep all 4 tubes ganged together.
Thanx
Scott