The 18watt build I'm currently working on has a Lite3 channel and a JCM800-style channel, which may be more along the lines of what you're looking for. I'll post more details once I tune it a little more.
--mark
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18 watt shredder?
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markh
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Jason
Death,
You could try a master volume, -FB, fixed bias, a Celestion with a BIG magnet/voice coil--like a G-12H100, a bigger OT and PT, and cascaded gain stages. If you want to build this into the standard 1X12 or 2X10 cab, you may have to do a bit of re-configuring of the lead dress and layout. It could be done though.
BTW, the preamp section would be easy to get a rip tone from if you build a single channel instead of the normal and trem channels. However, getting the power amp to not sag and take a lot of drive abuse would require a bit of work. Think about a solid state full wave rectifier or a bridge rectifier. Also, keep good tabs on your plate and screen voltages--EL-84's were only designed to withstand about 300VDC--and almost everybody pushes this by about 5%-20%, a lighter primary Z [say 5K to 7K or so]. You also probably want to scoop the mids a bit--so pay attention to the preamp coupling, bypass caps, slope resistor, pot values, etc. The JCM 800 preamp sounds killer. For good bass response and tight damping, I'd think about a lighter OT primary Z, about 350VDC--380VDC max, fixed bias, big Iron [overrated]. The Heyboer is just enough, but still has a bit of sag. I would try something along the lines of 50 Watt Power and Output Transformer, etc. Also, you probably want a higher slew rate and large power filters, OT, PT, coupling caps, gain stages, etc. all play into this.
Jason
You could try a master volume, -FB, fixed bias, a Celestion with a BIG magnet/voice coil--like a G-12H100, a bigger OT and PT, and cascaded gain stages. If you want to build this into the standard 1X12 or 2X10 cab, you may have to do a bit of re-configuring of the lead dress and layout. It could be done though.
BTW, the preamp section would be easy to get a rip tone from if you build a single channel instead of the normal and trem channels. However, getting the power amp to not sag and take a lot of drive abuse would require a bit of work. Think about a solid state full wave rectifier or a bridge rectifier. Also, keep good tabs on your plate and screen voltages--EL-84's were only designed to withstand about 300VDC--and almost everybody pushes this by about 5%-20%, a lighter primary Z [say 5K to 7K or so]. You also probably want to scoop the mids a bit--so pay attention to the preamp coupling, bypass caps, slope resistor, pot values, etc. The JCM 800 preamp sounds killer. For good bass response and tight damping, I'd think about a lighter OT primary Z, about 350VDC--380VDC max, fixed bias, big Iron [overrated]. The Heyboer is just enough, but still has a bit of sag. I would try something along the lines of 50 Watt Power and Output Transformer, etc. Also, you probably want a higher slew rate and large power filters, OT, PT, coupling caps, gain stages, etc. all play into this.
Jason
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