Shaffer & Hopkins JV14 (14 Watt High/Low Gain Marshall 2204 Circuit) ♫

NewReligion

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The JV14 is a (Joint Venture) 14 watt 3 & 4 stage high gain amp which cleans up well when the guitar is rolled down and brings it on when full up on both Low (3 stages of gain) & High (4 stages of gain).

It's concept came from my mentor, Terry Shaffer of Shaffer Amplification. Terry asked if I would be interested in joining him on this joint venture to which I said it would be my honor. Terry did the heavy lifting on building the entire amp in the circuit form of a Marshall 2203/2204 powered by a set of "6CM6" Power Tubes in addition to the buffered effects loop. The PCB is from Jason Tong a.k.a. Headfirst Amplification.

Once the amp was completed as a Marshall based 2204 circuit Terry delivered the amp to me in person December of 2021. I then began to reconfigure the preamp section & added the 4th stage of gain in a non coplanar point to point approach.

The intent was to offer a "Low Wattage" amplifier that carries a big sound in addition to responding to the guitarists touch, feel & use of the guitar.

Thank you Terry. I am humbled by your invitation. Your Friend, David...♫

 

pedecamp

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The JV14 is a (Joint Venture) 14 watt 3 & 4 stage high gain amp which cleans up well when the guitar is rolled down and brings it on when full up on both Low (3 stages of gain) & High (4 stages of gain).

It's concept came from my mentor, Terry Shaffer of Shaffer Amplification. Terry asked if I would be interested in joining him on this joint venture to which I said it would be my honor. Terry did the heavy lifting on building the entire amp in the circuit form of a Marshall 2203/2204 powered by a set of "6CM6" Power Tubes in addition to the buffered effects loop. The PCB is from Jason Tong a.k.a. Headfirst Amplification.

Once the amp was completed as a Marshall based 2204 circuit Terry delivered the amp to me in person December of 2021. I then began to reconfigure the preamp section & added the 4th stage of gain in a non coplanar point to point approach.

The intent was to offer a "Low Wattage" amplifier that carries a big sound in addition to responding to the guitarists touch, feel & use of the guitar.

Thank you Terry. I am humbled by your invitation. Your Friend, David...♫


Sounds great David, which of your mods did you add to it?
 

Guitar-Rocker

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I think I can explain. Two fold reasons actually. First off, I have minor hearing damage in the upper range registers from being an Industrial Electrician for most of my life. And when El84's hit that range as they are pushed, for me it's like "fingernails on a chalk board". I literally have to leave the area where they are being played aggressively.

The other reason I prefer the 6CM6's is that they share similar specs with the 6V6's, only in a smaller glass envelope. I prefer that tone of the 6CM6's over the EL84's, as I think they have all of the good aspects of both the EL84 and the 6V6, much like a cross between the two tubes, and to me exhibit none of the ear fatigue issues.

Before I get slayed on here, yes for sure there are damn fine EL84 amps out there , but this is the route that we chose to go.
 

DirtySteve

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I have the same problem with EL84 tubes. I thought it was my speakers or my pickups or anything else I could blame it on and I spent a lot of money trying to fix the problem. I had several el84 amps and since I thought the problem was something other than the amp it made sense that every amp I tried I still had the issue. I took me a long time before I finally figured out it was the el84s.
 

Guitar-Rocker

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To me it's a shame that I cannot tolerate the EL84, because the tube does distort nicely, and a builder has more choices of iron, depending on the desired net result.

I sold a killer EL84 amp to a local up in Indianapolis, who loved the tone, but after two weeks he came back and asked if he could trade it back in for a different amp because as he put it "those tubes are killing my ears".
 

Gene Ballzz

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Some great descriptions and examples of why & how a VOX AC30 can "cut through a mix" so well, but be kind of tiring to the ears over long periods of time! There is a very fine line between being effectively "present" in a mix and being "fatiguing" to the ears! Music is intended to be pleasing and relaxing to the ears, NOT painful!
Just My :2c:,
Gene
 


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