Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: shaun on April 01, 2020, 07:26:32 pm

Title: 6G2 question
Post by: shaun on April 01, 2020, 07:26:32 pm
Hi All. Hope everyone is in good health.

The schematic shown here lacks the tremolo that often comes with the 6G2. So my question is whether this is a complete schematic. If it is, I don't quite understand how the output tube bias works. And if it is, I wonder what that little X in the box, coming off the B+, means - - buried treasure?

Cheers all.
Title: Re: 6G2 question
Post by: sluckey on April 01, 2020, 07:43:57 pm
That schematic was hacked to remove the trem, but it was done by someone that doesn't know what they are doing. The schematic will not work as is.

Best to get schematics from a reputable source such as Hoffman's library. Look at this to solve the X in a box mystery.

     https://el34world.com/charts/Schematics/files/Fender/Fender_princeton_6g2_schem.pdf
Title: Re: 6G2 question
Post by: shaun on April 01, 2020, 07:48:23 pm
Thanks Sluckey. That's what I figured.
Title: Re: 6G2 question
Post by: shaun on April 01, 2020, 07:56:16 pm
In that light, can anyone suggest a simply 6V6 PP amp schematic? I don't need any reverb or trem; just a simple amp, preferably using a 5Y3 rec.
Cheers.

Actually, I suppose a 5E3 with only one input might be close.
Title: Re: 6G2 question
Post by: sluckey on April 01, 2020, 09:18:15 pm
There are literally hundreds of amps that meet your criteria. Take a look in the library. It's fun. You got time, right?
Title: Re: 6G2 question
Post by: shaun on April 01, 2020, 09:20:15 pm
Ha! Yeah, quite a lot of it, actually:).
Title: Re: 6G2 question
Post by: shooter on April 02, 2020, 07:50:39 am
 :icon_biggrin:

SilverTone 1482
(hack off the trem)
Title: Re: 6G2 question
Post by: 66Strat on April 02, 2020, 11:21:41 am
5D3 Deluxe.  :headbang:
https://el34world.com/charts/Schematics/files/Fender/Fender_deluxe_5d3_schem.pdf

Title: Re: 6G2 question
Post by: shaun on April 02, 2020, 01:01:47 pm
The 5D3 looks interesting, although that wiring is probably trickier than it looks at first glance. I also came across this version of the 1482, which looks about as simple as it gets, although I'd put the extra half of the 12ax7 to use in the preamp section - I'd probably insert the typical TB stack between the triodes.
Title: Re: 6G2 question
Post by: shooter on April 02, 2020, 01:12:28 pm
Quote
I'd probably insert the typical TB stack
not a player so.......
if you're a constant knob tweaker sure, otherwise I'm finding I can get what I want in about a minute, then all the knob twisting I need is on the guitar.

Look at the early pages of my thread, Sluckey did a layout for Platefires build, came in handy.  That version is "an upgrade" from the schematic you posted.
Title: Re: 6G2 question
Post by: shaun on April 02, 2020, 02:07:20 pm
Ah. Very cool. Thanks shooter!
Title: Re: 6G2 question
Post by: shaun on April 02, 2020, 03:08:01 pm
Actually, now that I've looked more closely at the 5D3, it couldn't be much simpler. So thanks 66Strat. I think that's what I'm gonna build. Cheers.
Title: Re: 6G2 question
Post by: bmccowan on April 02, 2020, 03:35:17 pm
Not trying to talk you out of a 5D3, as that will be a fine project. Just throwing out some other ideas:
Z-28 - I built one of these and then rewired the preamp for a 5879 instead of a EF86 - One of my favorites
Route 6V6 - based on a Z Route 66 - simple amp with a great sound - I built mine in an old Bogen chassis reusing the iron.
Any of the earlier Gibson 2-6V6 amps - GA40 Ls Paul amp can easily be done without the trem channel.
Valco 2-6V6 amps - the Thunderbolt preamp is very simple and can be easily done with 6V6s
And of course you can go back to your original idea of the 6G2 non trem - you just need a corrected schematic.
Hey, the way things are going, you might have time to make all of them.
Title: Re: 6G2 question
Post by: shaun on April 02, 2020, 04:59:57 pm
Thanks bmc. I'll look through those schematics. If I don't use them now, it will be good to have them in my filing system next time I do a build. Much appreciated.
Title: Re: 6G2 question
Post by: bmccowan on April 02, 2020, 05:50:10 pm
BTW - I LOL'd at the buried treasure remark. Bravo Zulu
Title: Re: 6G2 question
Post by: tubenit on April 03, 2020, 06:53:56 am
Here is one to throw into the mix of things to consider.  A  "minimalist" 6V6 Plexi with boost switch, passive FX and PPIMV using only two 12AX7's, two 6V6's and a 5V4 or 5Y3.  For a minimalist approach, it has a lot going for it.

I drew this up just for you to look at...………….  :icon_biggrin:

The mosfet cathode follower is very easy to implement and the mosfet in the CF position does NOT hinder the tone at all. In fact, I can't tell any difference between a tube triode or a mosfet as a CF. The link is to ARCHIVE about mosfets complete with photos, schematics and layouts.  I have a mosfet CF in my current HoSo56 the minimalist 6BM8 amp.

http://el34world.com/Forum/index.php?topic=21873.0

With respect, Tubenit
Title: Re: 6G2 question
Post by: DummyLoad on April 03, 2020, 08:38:58 am
no trem 6G2 that should work. see attached. 30K in bias supply might need to be swapped for 33K to 43K to get close(r) to -37V.

good luck! 


--pete
Title: Re: 6G2 question
Post by: bmccowan on April 03, 2020, 09:38:56 am
Still looking for the buried treasure though, eh?