bluesky636
Active Member
- Joined
- May 4, 2015
- Messages
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Just completed my latest and last amp build (I'm 68 years old and have built a Fender 5F6A, Fender 5F1, Trainwreck Express, and heavily modified a Fender Blues Deluxe Reissue, and Fender Champion 600 Reissue. I think that's enough.), a Fender 5E8A head.
All my builds have been based on Weber's kits to which I have added my own little tweaks. Note that the Weber kits do not come with instructions, only a schematic and wiring diagram. You do need to know what you are doing. I have a BSEE (1976, the last year that vacuum tubes were part of the curriculum) and learned to solder while in college.
The head version of the Weber 5E8A is unusual in that the chassis is the same chassis as used in their 2x12 combo cabinet kit. As a result, when built as a head the tubes sit parallel to the bottom of the head instead of hanging vertically.
The head is then plugged into a Crate 4x12 cabinet loaded with 16 ohm Celestion G12M-25 reissues. The cab is wired to allow a choice of stereo 8 ohms, mono 4 ohms, or mono 16 ohms. The output transformer of the 5E8A is 4 ohms.
The power transformer is wired for 120 VAC input (as are all my amps). My wall outlets measure between 122 and 124 VAC so I use a AmpRX Backline Power Station to bring the voltage down to about 118 VAC. Power tubes (JJ 6L6GCs) are biased about 60% (still tweaking the bias). Preamp tubes are JJ 12AX7s (2) and JJ 12AX7s for the voltage amp and phase inverter. Weber Copper Cap WU4GBs (2) are the rectifiers. I've added a bias adjustment pot to the front panel to be used with a dual bias probe.
That's about it for technical details so here are some photos. I have ordered name and serial number plates for front and back. Hope you like.
All my builds have been based on Weber's kits to which I have added my own little tweaks. Note that the Weber kits do not come with instructions, only a schematic and wiring diagram. You do need to know what you are doing. I have a BSEE (1976, the last year that vacuum tubes were part of the curriculum) and learned to solder while in college.
The head version of the Weber 5E8A is unusual in that the chassis is the same chassis as used in their 2x12 combo cabinet kit. As a result, when built as a head the tubes sit parallel to the bottom of the head instead of hanging vertically.
The head is then plugged into a Crate 4x12 cabinet loaded with 16 ohm Celestion G12M-25 reissues. The cab is wired to allow a choice of stereo 8 ohms, mono 4 ohms, or mono 16 ohms. The output transformer of the 5E8A is 4 ohms.
The power transformer is wired for 120 VAC input (as are all my amps). My wall outlets measure between 122 and 124 VAC so I use a AmpRX Backline Power Station to bring the voltage down to about 118 VAC. Power tubes (JJ 6L6GCs) are biased about 60% (still tweaking the bias). Preamp tubes are JJ 12AX7s (2) and JJ 12AX7s for the voltage amp and phase inverter. Weber Copper Cap WU4GBs (2) are the rectifiers. I've added a bias adjustment pot to the front panel to be used with a dual bias probe.
That's about it for technical details so here are some photos. I have ordered name and serial number plates for front and back. Hope you like.
