Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: p2pAmps on June 23, 2021, 05:51:16 pm

Title: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 23, 2021, 05:51:16 pm
This is a single channel AB763-ish with added presence control and a good ole 3 knob verb (Dwell, mix, tone) and no trem circuit.  I also added an attenuator of sorts as this bad boy is hot in the frontend.  So far I have built about a dozen and I think we have a good one here from the reports.  Thought I would share with your guys. 

Note: the music playing through it is my pal Travis Toy as it's hard to test things with a guitar in my hand (plus I suck)

Cheers

Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: jordan86 on June 23, 2021, 07:17:00 pm
Gorgeous. That’s an amp I’d love to build. Similar to a Dr Z EZG50 but with twice the power I imagine?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: sluckey on June 23, 2021, 07:41:03 pm
Want to share the schematic?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 23, 2021, 07:47:33 pm
Want to share the schematic?

Yeah if I had one LOL.  I need a master like you to draw me one up "hint hint"
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: sluckey on June 23, 2021, 08:21:45 pm
I might could do that. Need a lot more than a short video though.
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 23, 2021, 08:22:57 pm
I might could do that. Need a lot more than a short video though.

I'll shoot you a call Steve...
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: tubeswell on June 24, 2021, 01:31:56 am
Want to share the schematic?

Yeah if I had one LOL.  I need a master like you to draw me one up "hint hint"


Something like an Allen Old Flame?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 06:07:33 am
Something like an Allen Old Flame?
[/quote]

I'm not sure as I have never looked at any Allen amps.  I know who David is however and he certainly has a great reputation with his stuff. 
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: Ed_Chambley on June 24, 2021, 07:16:10 am
Sounds like Alabama Jubilee. Whatever you are building there is hardly ill concieved.  Now PTP, just incase you can use this amp with a telecaster, there are some very cool links here.  Brent cannot sing, but he doesn't need too.


Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 07:20:50 am
Sounds like Alabama Jubilee. Whatever you are building there is hardly ill conceived.  Now PTP, just in case you can use this amp with a telecaster, there are some very cool links here.  Brent cannot sing, but he doesn't need too.

Hey Ed!  Brent can certainly play that Tele huh :). Did some work on some of his gear and he is a great guy as well.  Good times
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: Ed_Chambley on June 24, 2021, 07:25:22 am
Sounds like Alabama Jubilee. Whatever you are building there is hardly ill conceived.  Now PTP, just in case you can use this amp with a telecaster, there are some very cool links here.  Brent cannot sing, but he doesn't need too.

Hey Ed!  Brent can certainly play that Tele huh :). Did some work on some of his gear and he is a great guy as well.  Good times
That he is.  I couldn't believe it when I was introduced to him.  I knew the name and all his work to that point, but I thought he would be hip, you know.  Naw, he is nerdier than me and you put together.
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: Ed_Chambley on June 24, 2021, 07:28:53 am
Now what it the "Attenuator?" A master volume of some sort?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 07:32:26 am
Now what it the "Attenuator?" A master volume of some sort?
Same sort of effect Ed.  It really is a way to back off the pre-amp section where it ties to the power section.  This amp has a hot front end and is just so loud.  I pulled the 220K mix resistor and added a 250K pot as a test and it worked out really nice without changing the sound of the amp at all.  That being said I decided to incorporate into all future Bad-Dawgs and have added to most of the existing ones I have built (about a dozen or os)
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: sluckey on June 24, 2021, 07:35:53 am
Said another way, it's a pre PI MV, just slightly different from this...

     http://sluckeyamps.com/tdr/tdr.pdf
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: Ed_Chambley on June 24, 2021, 07:51:33 am
I got ya!  I know you have sold these because I am a you tube stalker.  I was thinking you would want to stay clean being made to play Pedal Steel.
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 07:53:43 am
I got ya!  I know you have sold these because I am a you tube stalker.  I was thinking you would want to stay clean being made to play Pedal Steel.

Yes I had steel guitar in mind with this but turns out it's a pretty good guitar amps as well if you want that loud and clean thing.  I use pedals anyway so it works for me.
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: Ed_Chambley on June 24, 2021, 08:00:21 am
I got ya!  I know you have sold these because I am a you tube stalker.  I was thinking you would want to stay clean being made to play Pedal Steel.

Yes I had steel guitar in mind with this but turns out it's a pretty good guitar amps as well if you want that loud and clean thing.  I use pedals anyway so it works for me.
Yea, well, you probably good enough to play clean, but I have heard some string nasty sustaining guitar sounds coming from your fingers through a Princeton, but you do have the Nashville Studio geetar players secret weapon. I got one too.  The green Chinese overdrive.
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: Ed_Chambley on June 24, 2021, 08:01:56 am
BTW,  When did you finally turn off your Weller?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 08:07:55 am
BTW,  When did you finally turn off your Weller?

I just leave it on LOL
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: sluckey on June 24, 2021, 12:48:21 pm
I see the half power switch is not connected. What are your intentions? How will you connect it?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 01:09:17 pm
I see the half power switch is not connected. What are your intentions? How will you connect it?

Yeah it’s connected steve
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: sluckey on June 24, 2021, 03:15:05 pm
OK, so is it simply switching a pair of 6L6 cathodes in/out? Something else?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: sluckey on June 24, 2021, 03:17:45 pm
Also, what value filter caps and dropping resistors? Can you open the doghouse and take a hi-rez pic?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 03:33:47 pm
Also, what value filter caps and dropping resistors? Can you open the doghouse and take a hi-rez pic?

Caps are 2-100uF/350v and 3 22uF/450 F&Ts and dropping resistors are 3 watt 1K and 4.7K
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 04:20:21 pm
Also, what value filter caps and dropping resistors? Can you open the doghouse and take a hi-rez pic?

Here you go

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1624569573531-C5VC86LA3TDFQE5I1AE6/cap.JPG?format=2500w)
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: sluckey on June 24, 2021, 04:35:51 pm
Does this look like your power supply?

Did I get the PT primary wiring right?

Is the STBY switch in the right place?

Are you using 220K/1W balance resistors across the two series 100µF caps?

Tell me about your half power switch and how it's connected.
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 04:42:11 pm
Does this look like your power supply?

Did I get the PT primary wiring right?

Is the STBY switch in the right place?

Are you using 220K/1W balance resistors across the two series 100µF caps?

Tell me about your half power switch and how it's connected.

Did I get the PT primary wiring right?  Yes sir

Is the STBY switch in the right place?  Yes

Are you using 220K/1W balance resistors across the two series 100µF caps?  Yes but using 2 watt

Tell me about your half power switch and how it's connected.  1/2 power dumps ground on V5 and V8

Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 04:43:28 pm
Does this look like your power supply?

Did I get the PT primary wiring right?

Is the STBY switch in the right place?

Are you using 220K/1W balance resistors across the two series 100µF caps?

Tell me about your half power switch and how it's connected.

Also Steve, not using the filament center tap, using 2 - 100Ω to ground artificial center tap off the pilot
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: acheld on June 24, 2021, 06:49:58 pm
Curious:  How did you decide to use artificial center taps on the heaters rather than the filament center tap?
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 24, 2021, 08:50:54 pm
Curious:  How did you decide to use artificial center taps on the heaters rather than the filament center tap?

Because my PT doesn't happen to have a center tap for the filament windings :)


Cheers
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 28, 2021, 04:03:27 pm
Here is another Bad-Dawg I built over the weekend.  I get to keep this one for me finally! 

Also, big shout out to Sluckey for drawing me up a very nice schematic for this amp, the man knows his stuff I can tell you that.

Cheers

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1624914169358-2RBCL4DQKQV488DD3RP4/IMG_8857+2.jpg?format=2500w)
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: sluckey on June 28, 2021, 04:20:04 pm
Looks exactly like the other one. Even gat a green gator clip lead on the same PT bolt!    :icon_biggrin:
Title: Re: p2pAmps Bad-Dawg comin at ya
Post by: p2pAmps on June 28, 2021, 04:21:09 pm
Looks exactly like the other one. Even gat a green gator clip lead on the same PT bolt!    :icon_biggrin:

I like to be consistent cause I know you're watching!  This one has PRP resistors and grey zip ties too