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previous: dshepp806 I, too, am interested in a quad top... -- 1140476694 View Thread

Re: Ready, Fire! aim...

2/21/2006 10:14 PM
Jeff E
Re: Ready, Fire! aim...
Funny you should ask, Doyle - I just put the finishing touches on it last weekend after the cab and straggling parts came in.  
I used the Weber kit which ended up coming with a tweed Mojo cab and Weber signature alnico 12's. I built it with the kit parts with the following exceptions:  
- Installed the Collins mod (watch your mailbox, Bruce!)  
- Fender style pilot light assembly.  
- Replaced standby switch with a formerly original Fender bf ground switch.  
- Installed a front panel switch to select two- or four- tube operation. This involved running a 10w 150 ohm cathode resistor in series with a 5w 180 ohm resistor, each having its own 50uF bypass cap. In normal four tube operation the junction of the pair of resistors and caps is switched to ground, giving 150 ohms and 25uF, and the all four cathodes are connected together.  
Flip the switch to 5e3 mode and the connection between the inner and outer pairs' cathodes is broken and the effective resistance is 330 ohms with 25uF bypass.  
I run a 5Y3 with 2 6V6's and a GZ34 with 4 6V6's. For proper output impedance matching, the 4 ohm tap is used in 4 tube mode, and in 5e3 mode the 2 ohm tap is used.  
She sounds great with a tele, but still a little muddy with humbuckers for my taste. Addressing that will probably be my next project. I couldn't have gotten this far without the help of the guys here, especially Bruce Collins.  
As to your question about assembled boards, I'm not aware of any being available for the 5e3x2, though an assembled 5e3 board would lend itself to modification with different cap and resistor values.  
Good Luck!