High Power 6G2?

Uncle Daddy

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Say I wanted to theoretically build a higher power version of a Brownface Princeton, what would I need to change? The Mojotone chassis fits a 2 1/4 x 2 13/16 PT, same size as the TAD Deluxe Reverb, ([email protected] 160mA). The current PT is a gentle 650v C/tap @ 70mA. I know the sound would change a lot, but what else would need to be changed? There's not too many larger OTs with 8k, so I guess a DR O/T at 6.6k and 20w rating would match the P/T? Anything else?
 

Uncle Daddy

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Interesting, I'll stay tuned. I bet this isn't relevant to your quest, but at some point I'd be really tempted to build a 6G3 instead... ;-)

Been there, done that!
P1130847.JPG
 

Uncle Daddy

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TAD does a 6g3 PT that'll fit the Mojotone 6G2 chassis, with 325v @ 140mA. With the voltage the same as the current one, would I need to change much else other than the OT?
 

Willie Johnson

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You know what would be badass? A 6G2 configured as a head, a tube reverb unit, and an old rack-mount Blue Tube preamp, all crammed into one box, powering a 4x10 cab. Because that would be badass.
 

2L man

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Say I wanted to theoretically build a higher power version of a Brownface Princeton, what would I need to change? The Mojotone chassis fits a 2 1/4 x 2 13/16 PT, same size as the TAD Deluxe Reverb, ([email protected] 160mA). The current PT is a gentle 650v C/tap @ 70mA. I know the sound would change a lot, but what else would need to be changed? There's not too many larger OTs with 8k, so I guess a DR O/T at 6.6k and 20w rating would match the P/T? Anything else?
70mA PT on CT rectifier circuit use can deliver only about 100mA continuous average DC so it limits the output power and I would use only 6V6 or EL84 about 12W tubes.

160mA CT PT max DC average comes 225mA and should supply 6L6A, 5881 and EL34 and 6L6GC if OT impedance is 6k or more
 
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archetype

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Say I wanted to theoretically build a higher power version of a Brownface Princeton, what would I need to change? The Mojotone chassis fits a 2 1/4 x 2 13/16 PT, same size as the TAD Deluxe Reverb, ([email protected] 160mA). The current PT is a gentle 650v C/tap @ 70mA. I know the sound would change a lot, but what else would need to be changed? There's not too many larger OTs with 8k, so I guess a DR O/T at 6.6k and 20w rating would match the P/T? Anything else?

If you're willing to change the tone of the amp to get it to produce more power, what is it that you like about the 6G2? Seemingly not the tone.

IMO there is no louder Princeton. One can pursue making it produce more Wattage, but IMO anything like that produces tone that is not Princeton tone.

If it's just a fun technical exercise, then cool. Have at it and let us know what the result is. If you want louder and keep the same basic tone, try a more efficient speaker.
 

schmee

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A BF Vibrolux PT and a BF Deluxe or the largest 6600 primary OT you can find. I have these in my SF Princeton, and it adds clean headroom a lot.

Or go with the 6L6's and a Vibrolux OT/PT. The BF style I have done still retain much of the Princeton characteristics, due mainly to the Phase Invertor style is my guess.
 

Uncle Daddy

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If you're willing to change the tone of the amp to get it to produce more power, what is it that you like about the 6G2? Seemingly not the tone.

IMO there is no louder Princeton. One can pursue making it produce more Wattage, but IMO anything like that produces tone that is not Princeton tone.

If it's just a fun technical exercise, then cool. Have at it and let us know what the result is. If you want louder and keep the same basic tone, try a more efficient speaker.

I love the 6G2, it's the perfect indoor amp and I really enjoyed building it. It doesn't have that over intrusive bottom end of the Princeton Reverb, and cuts through nicely. I was thinking of building another, just with a bit more oomph, really. My 6G3 is an animal, and doesn't play nicely with the neighbours! I don't need any more volume, but I do like a wolf in sheeps' clothing!
 

archetype

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I love the 6G2, it's the perfect indoor amp and I really enjoyed building it. It doesn't have that over intrusive bottom end of the Princeton Reverb, and cuts through nicely. I was thinking of building another, just with a bit more oomph, really. My 6G3 is an animal, and doesn't play nicely with the neighbours! I don't need any more volume, but I do like a wolf in sheeps' clothing!

Just like Don Henley said, build that perfect beast.
 

archetype

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Might be the speaker. Got a Weber 12 sig alnico smoothcone in it.

The Sig 12A smooth cone should be close to retro Jensenish. The smooth cone should be giving you early breakup, but not really emphasizing low end. If you want that breakup I'd think it's ideal.
 




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