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I was wondering if the a Trinity 18 Watt Plexi could run 6V6 tubes easily vs EL84s. (No major changes to circuit or transformers except tube sockets and wiring to them) like a Reinhardt MI-6, or would you need a different OT.

The Triwatt has made the JJ 6V6 my favorite tube.

Yes, I know you make the V6, but I am of the mind that the less tubes, less switches, & less wiring = less problems.

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ROB

Just bigger sockets and changed wiring, plus a couple of resistor value changes. You have to change the power tubes' cathode resistor to something like 270 ohms IIRC (ie whatever the V6 schematic shows). Also change the PI's tail resistor to 22k. As you have the Plexi version there, the PI's cathode resistor is probably already 470 ohms, unless yours is an earlier version of the Trinity Plexi. If it isn't 470 ohms already, then it's also recommend to change it to that value.

FYI some folks think of JJ 6V6s as "current day NOS" tubes.

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Great tones come in small glass jars!

I don't have the "18 Watt Plexi" yet. (Future Winter Project)

I was comparing the the layouts of the V6 to the standard 18 Watt, and there is not that much more wiring. The only thing is I think(?) the V6 only comes in a "Head Style Chassis", but I would most likely built a head anyway.

Thanks:

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ROB

You can build a 6V6 amp no problem in a combo, just cant have both 6V6 & EL84 like in the v6 modle we have. In a head you can have both.

Pretty straightforward change and fun too!

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Coco I haven't looked at the schematics or layout but I'm wondering how close this would be to a Mark Huss Plexi???

Here's Marks http://mhuss.com/Plexi6V6/Plexi6V6.gif
and the trinity is in the resources section. Same "basic" layout but some different values.

Marks circuit is pretty different but the concept works as far as a 6V6 Marshall goes. Marks is a difernt best from design perspective though, fixed bias is just one difference.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Yes, in reality they're coming at a similar goal from two opposite directions. One is from the Marshall 18W, cathode biased, tube rectifier, no NFB type amp, but with 6V6 tubes. The other is the classic Marshall Plexi design with fixed bias, NFB, SS rectification, etc, using 6V6s. Both make for nice Marshall style amps.

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Great tones come in small glass jars!

Coco and ZP thanks for the replies. Aside from the design differences what, if any, are the sonic differences? I'm trying to decide on whether or not to do a 20 watt 6v6 1987x style or the real 50 watt deal. With VRM(VVR) becoming so popular and easy to implement I'm starting to wonder why I should even bother with a 6v6 version.

Thoughts and comments appreciated.

Thanks

A VVR/VRM is real easy to install into a cathode-biased amp like a Marshall 18W. However, it's quite a bit more complicated with a fixed-biased amp, and requires a special kind of VVR. So that option would be equally difficult both on a Mark Huss style 6V6 Plexi or 50W Plexi. Both give similar tones, although the 6V6 version is a little smoother and creamier, with excellent detail. From personal experience I can also tell you that a 6V6 Plexi is one real loud amp. Both those amps are also more complex builds than a regular 6V6 18W. IMO if you want to regulate the power of a fixed biased amp, like a Plexi, a variac on the PT is by far the best and simplest way, provided you use a separate filament transformer to keep the heaters at 6.3V.

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Great tones come in small glass jars!

SPAM!!

Although the V6 could be an option, simplifying with fewer tubes, switches, and wiring might indeed reduce potential issues. Pokerogue