The "Stone Cold Bitch"

Guitar-Rocker

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Hey all, This build started off completely as another amp, and I've rebuilt it into what it is now. It's now a 14watt 6V6 modified version of a Friedman Brown Eye idea.

This has a typical High / Low set of input jacks, but they are nothing like a Friedman's BE. Low input is it's own separate 33K input, High is it's own separate 33K input.

On low the 33k input goes through a 12AX7 stage, voiced at 180K plate with a 2.7K/ .68uF cathode. Much like a hot rodded Bright channel of a Marshall Plexi. This stage goes to the "Overdrive" pot. Near the "Overdrive" pot is a mini switch that serves two functions. If the mini switch is toggled up, then that pot becomes a "Volume/Overdrive" function that bypasses the tonestack and goes through the FX loop to the phase invertor, producing a glorious clean tone. If the mini switch is toggled down, then that "overdrive pot" acts like a hot rodded Plexi "Bright channel" that goes through the tonestack, to the FX loop, then to the phase invertor.

If you plug into the high jack the 33K input goes through the other 12AX7 stage, voiced at 120K plate with a 820R/ 2.1uF cathode. This stage goes through the coupling cap, through a voltage divider and cascades into the other 12AX7 stage. The signal then goes through the "Overdive" pot which now acts as a straight "Gain" pot on to the CF stage, then through the tonestack, FX loop, Master Volume to the phase invertor. As much gain as needed.

The chassis is a Modulus aluminum chassis, PT is a stand up Hammond, OT is a MPS OT20PP. Power tubes are Raytheon Made in England Black glass 6V6GTA rated at 14 watts, jacks are Cliff, pots are CTS, resistors are Draloric, plate resistors are 2W Vishay metal films, preamp coupling caps and the tonestack caps are Mullard/Philips mustard caps, ERO coupling caps in the power amp, Belton sockets, old stock preamp tubes, Carling switches, tube rectified with a old stock 5V4 and the amp is cathode bias. It turned out to be a really fine toned amp. I have to have the proper faceplate made, I used an old recycled plate for temporary. Pics below:









 

john l

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Great looking build Terry. Ive always thought your low watt plexi amps looked like fun. Do you have a link or a series name for those dark brown vishay metal films? Think Id like to give them a spin on a couple things.
 

Guitar-Rocker

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John, I buy the Vishay / BC Components 2 watt resistors at mouser. They are the same physical size as a typical 1/2watt carbon film. These are the PR02 series and all of them start with Mousers part number of 594-5083NW, then the value afterwards. Such as a 1.5K has a Mouser part number of : 594-5083NW1K500J. They are 2Watt metal film. The product category is passive components>resistors>film resistors>metal film resistors-through hole with Vishay as the vendor and the watts rating at 2 watts
 

NewReligion

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Hey all, This build started off completely as another amp, and I've rebuilt it into what it is now. It's now a 14watt 6V6 modified version of a Friedman Brown Eye idea.

This has a typical High / Low set of input jacks, but they are nothing like a Friedman's BE. Low input is it's own separate 33K input, High is it's own separate 33K input.

On low the 33k input goes through a 12AX7 stage, voiced at 180K plate with a 2.7K/ .68uF cathode. Much like a hot rodded Bright channel of a Marshall Plexi. This stage goes to the "Overdrive" pot. Near the "Overdrive" pot is a mini switch that serves two functions. If the mini switch is toggled up, then that pot becomes a "Volume/Overdrive" function that bypasses the tonestack and goes through the FX loop to the phase invertor, producing a glorious clean tone. If the mini switch is toggled down, then that "overdrive pot" acts like a hot rodded Plexi "Bright channel" that goes through the tonestack, to the FX loop, then to the phase invertor.

If you plug into the high jack the 33K input goes through the other 12AX7 stage, voiced at 120K plate with a 820R/ 2.1uF cathode. This stage goes through the coupling cap, through a voltage divider and cascades into the other 12AX7 stage. The signal then goes through the "Overdive" pot which now acts as a straight "Gain" pot on to the CF stage, then through the tonestack, FX loop, Master Volume to the phase invertor. As much gain as needed.

The chassis is a Modulus aluminum chassis, PT is a stand up Hammond, OT is a MPS OT20PP. Power tubes are Raytheon Made in England Black glass 6V6GTA rated at 14 watts, jacks are Cliff, pots are CTS, resistors are Draloric, plate resistors are 2W Vishay metal films, preamp coupling caps and the tonestack caps are Mullard/Philips mustard caps, ERO coupling caps in the power amp, Belton sockets, old stock preamp tubes, Carling switches, tube rectified with a old stock 5V4 and the amp is cathode bias. It turned out to be a really fine toned amp. I have to have the proper faceplate made, I used an old recycled plate for temporary. Pics below:










I love your ideas applied here Terry. Always keeping the R & D fresh. Very clean layout & dress. I especially like your choice choice & use of components in key positions.

Looking forward to some tones before g brother.

Thanks for sharing your skills & work.

David
 


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