What is it that defines a Wreck?
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What is it that defines a Wreck?
This is an honest, curious question I'm asking. I've listened to Youtubes and read threads till I'm stupid, but I want to know wherein the magic lies in terms of the circuitry. I ask because I have a Crate Vintage Club 20 that I built into a head years ago. It's a non reverb model, but has a hole for a third 12ax type tube and two EL84s. It has a good PT, but I'll replace the OT with a Hammond 125se if that helps. I'm game to gut it and think it would be fun to build a Mini-Wreck so I'm open to opinion, pictures, links, help, etc.
"I fought the Tone . . . and the Tone won"
Re: What is it that defines a Wreck?
Around here, a 'Wreck' would be one of three well documented amplifier models designed by Ken Fischer. They are the 2x EL-34 or 2x 6V6 Express, the 4x EL-84 Liverpool, and the 4x EL-84 Rocket. The Liverpool and Express are relatively high gain when compared to a tweed Bassman and the Rocket is very much like a Vox AC-30. Some 2x EL-84 versions of the Liverpool and Rocket have been built.
Performance of all three is more sensitive to lead dress, voltages, and component specifics than one would expect. The gain structure of the Express & Liverpool is somewhat unique. I don't believe in magic.
Performance of all three is more sensitive to lead dress, voltages, and component specifics than one would expect. The gain structure of the Express & Liverpool is somewhat unique. I don't believe in magic.
Re: What is it that defines a Wreck?
That sounds fine, but can anyone point me to a layout for 2 - EL84's based on a Wreck type of circuit?
"I fought the Tone . . . and the Tone won"
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skyboltone
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Re: What is it that defines a Wreck?
Just use the express circuit and layout except obviously the pin outs of the EL-84. Change the PI bias resistor to 1K and the tail to 39K. I've used 8K primarys and I've used 10.5K primarys. I'm still trying to make up my mind which I like. I haven't heard the two side by side. U2 (Dana) uses 10.5K primarys when he builds them. The output impedence of a pair of tubes in push pull changes depending on the amount of NFB. I'm sure either OT would sound the same depending on the amount of NFB. The 10.5K sorta copies the Liverpool lashup with 100K back from the 8 ohm tap. I make mine with fixed bias but I don't think anyone else is doing that. Try a 150 ohm instead of 130 ohm cathode bias resistor, or better yet put in a 250ohm adjustable.mike9 wrote:That sounds fine, but can anyone point me to a layout for 2 - EL84's based on a Wreck type of circuit?
.02
Dan
The Last of the World's Great Human Beings
Seek immediate medical attention if you suddenly go either deaf or blind.
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Seek immediate medical attention if you suddenly go either deaf or blind.
If you put the Federal Government in charge of the Sahara Desert, in five years time there would be a shortage of sand.
Re: What is it that defines a Wreck?
I kinda do believe in magic, FWIW. That said, if I had to name an ingredient in the TW build it would be the circuit path's directness - from input to output.
In fact, the circuit is so uncomplicated, you can only build a one channel version if you want it to be what KF intended. A two channel amp has resistive loads that keep one channel from interferring with the other, for example, just to get the volume pots to work properly or the reverb channel to function properly, etc.. So a TW is a one channel amp without effects because of this 'direct path' circuit idea, which is kinda unique.
The last point I would make to define its true beauty is the way the entire circuit is built 'in balance'. Which is to say that everything kinda 'craps out' at the same time? In other words the preamp isn't too gainy that it distorts before the power amp section distorts. It all happens at the same time which translates to................BEAUTIFUL GUITAR TONE AND A BEAUTIFUL FEELING AS YOU PLAY!!!!!!!!!!!!! You are just 'hooked up', tapping the JUICE, whatever you want to call it. Once you have the experience of this, things will change for you as a gtr player, I really believe this to be true. And this then, is my reference to 'magic'. And it does seem like magic when you have played everything under the sun and not had quite this experience. To be connected like this to your music, well, what can this be called if not MAGIC?
In fact, the circuit is so uncomplicated, you can only build a one channel version if you want it to be what KF intended. A two channel amp has resistive loads that keep one channel from interferring with the other, for example, just to get the volume pots to work properly or the reverb channel to function properly, etc.. So a TW is a one channel amp without effects because of this 'direct path' circuit idea, which is kinda unique.
The last point I would make to define its true beauty is the way the entire circuit is built 'in balance'. Which is to say that everything kinda 'craps out' at the same time? In other words the preamp isn't too gainy that it distorts before the power amp section distorts. It all happens at the same time which translates to................BEAUTIFUL GUITAR TONE AND A BEAUTIFUL FEELING AS YOU PLAY!!!!!!!!!!!!! You are just 'hooked up', tapping the JUICE, whatever you want to call it. Once you have the experience of this, things will change for you as a gtr player, I really believe this to be true. And this then, is my reference to 'magic'. And it does seem like magic when you have played everything under the sun and not had quite this experience. To be connected like this to your music, well, what can this be called if not MAGIC?
Most people stall out when fixing a mistake that they've made. Why?
Re: What is it that defines a Wreck?
Thanks again - it's starting to make some sense. Rooster that was damn near poetic - 
"I fought the Tone . . . and the Tone won"
Re: What is it that defines a Wreck?
Damn double post again 
"I fought the Tone . . . and the Tone won"
Re: What is it that defines a Wreck?
Mike - do yourself a favor and use a better OT than the Hammond... If you are going to the trouble of building this, find an old output tranny from a Scott or Magnavox stereo on fleabay that ran 2xEL84's per side, or better still a Heyboer OT for an 18 watt clone.
Trust me, it's worth the few extra dollars.
Trust me, it's worth the few extra dollars.
Re: What is it that defines a Wreck?
One Heyboer 18 watter on the way - thanks for that one.doctord02 wrote:Mike - do yourself a favor and use a Heyboer OT for an 18 watt clone. Trust me, it's worth the few extra dollars.
"I fought the Tone . . . and the Tone won"