6SJ7 Pentode 18 watt Lite...Formerly the ABSOLUTE Minimum

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StarGeezers
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6SJ7 Pentode 18 watt Lite...Formerly the ABSOLUTE Minimum

Post by StarGeezers »

Would anybody know of the schematic for an ultra simple 18watt... No MV, No TMB, one channel , perhaps a Tweed TC??? Or should we just de-construct the circuit into what we want??? Any assistance would be Greatly appreciated...!!!
We're planning a basic 18Watt P2P in a VJr chassis... :D
Last edited by StarGeezers on Sat 01/15/11 7:57 am, edited 1 time in total.
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kd
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Post by kd »

Look in the downloads section for an 18 Watt Lite llb. It's a simple circuit and an outstanding amp.

Ken
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sub
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Post by sub »

This is the 18W Lite :wink:
Best amp ever :twisted:
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cGil
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Post by cGil »

Okay, one lite coming up. But don't you want the meal deal with the double meat & triple cheese, super size fries, and extra thick jumbo shake with that? After all, it's a lite, so you're cutting down on the calories. :lol:

Gil...
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Post by BBQLS1 »

Even simpler, try the minimalist.
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Post by veets »

+1 on the Minimalist--big benefit here is that it has parallel triodes for the preamp = mo gain. And you can always add a tone control if you like.
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kd
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Post by kd »

The lite llb also has parallel triodes that are switched in an out of parallel at the input jacks.

Ken
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Post by keith »

The Minimalist would be even better if the parallel triodes were drawn as a cascode (cascade?) configuration. I have wired several amps this way, and it literally and absolutely beats the hell out of the parallel version.
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cGil
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Post by cGil »

Hey, why not use sacrifice another one of those of those 6SJ7's you're sitting on and go 'Roctal' with it. You could even throw in a TMB stack with that up front and still have gain to spare.

Gil...
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Post by StarGeezers »

So many possibilities/choices... :? More schematic reading,head scratching :roll: just that my limited skills and simple needs have kept me to the simplest amps possible in the past...P2P w/T strips..
:oops:
cGil, Drat!!! Now you've got me thinking of the Octal business ...I wanted to try the PP EL84' ,but the 6SJ7, AU driver and a couple 6V6's would be NICE too 8O May have to build BOTH ... :D Sure glad I have some extra chassis ..
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Post by zaphod_phil »

Maybe start minimal first time round, and then build the frankenamp with everything thrown in. :)
kd wrote:The lite llb also has parallel triodes that are switched in an out of parallel at the input jacks.
The main difference between the Minimalist and the Lite II is the latter has the tone control, and the two input jacks for single or parallel triodes.
keith wrote:The Minimalist would be even better if the parallel triodes were drawn as a cascode (cascade?) configuration. I have wired several amps this way, and it literally and absolutely beats the **** out of the parallel version.
You could do either. Cascade generally gives more gain than cascode, while cascode sounds somewhat more like a pentode.
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StarGeezers
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Post by StarGeezers »

ZP, "Sound" advice!!! (excuse the pun)...Now where might one find these schematics??? I looked in the downloads with no luck...??? :oops:
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Post by kyoungsteadt »

Geezer,

How about the minimalist with a 6SJ7 as the preamp tube, into 12AX7 PI. I think that would sound really thick and fat. You might even want to consider a pair of 6V6s instead of EL84s in a build.
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Post by StarGeezers »

Considering, considering , Oh my brain hurts !!!! Read :lol:
I can see myself ending up with as many 18watters as I now have Se amps 8O veryhappy
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Post by zaphod_phil »

FYI Lite IIb schematic and layouts are here - http://www.18watt.com/modules.php?name= ... oad&cid=26
Minimalist is on http://www.18watt.com/modules.php?name= ... oad&cid=27
EF86 preamp layout (which can also use a 6SJ7) is at http://www.18watt.com/modules.php?name= ... it&lid=156
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Post by StarGeezers »

ZP, Many many THANKS!!!!!!!! :D I'll start studying them ... WOW !!! That's GREAT stuff....PERFECT!!!! :thumbsup:
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Post by BBQLS1 »

If he's putting this in a VJ chassis, then the minimalist will have a SS rectifier, which will be good for the real estate. The VJ chassis really doesn't have much room.


BTW, I'm right up the road from you!
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Post by StarGeezers »

Yes, simple SS rect....B, our last SE builds in the VJr chassis have been pretty empty...using P2P and T strips ..gobs of room ...Don't see too much of a problem ... a board might crowd things considerably... 8O
Right up the creek eh??? Cool !!!
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Post by bigbeck »

kyoungsteadt wrote:Geezer,

How about the minimalist with a 6SJ7 as the preamp tube, into 12AX7 PI. I think that would sound really thick and fat. You might even want to consider a pair of 6V6s instead of EL84s in a build.
I just did that but with 6l6's instead. Very fat and perhaps it's a little too clean when cranked. Still sounds fantastic. Maybe I'll dump the 6sj7 and cascade a 12ax7. Sort of like a Super Superlite. :wink:
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Post by kyoungsteadt »

I think Geezer will be ok though since his band requires a cleanish tone for a lot of their material.
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