Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: p2pAmps on April 27, 2020, 04:37:13 pm

Title: Single Channel AB763 project
Post by: p2pAmps on April 27, 2020, 04:37:13 pm
Hey There Amp builders,

Here is a little Diddy I'm playing around with.  It's a single channel AB763, no tremolo, 3 knob reverb, 1/2 power switch, Presence control, 4-8-16Ω, 4 6L6GC just for fun :)

Thanks to Doug for a great turret board.  I am hoping for loud / clean amp for steel guitar players or players that dig using pedals etc.  Thinking this will need to be a 2x12. 

Anyway, here is a link to see all the pics so far if you like that sort of thing.
http://www.p2pamps.com/bad-dawg (http://www.p2pamps.com/bad-dawg)

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588022812570-ZWY2OYB7Z2AFRWUTM10J/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/BD-1.JPG?format=2500w)

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588022825743-X5XCYL7I7P5E3GJ2ZLO5/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/BD-3.JPG?format=2500w)

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588022872072-TUXT6VBA41LVVLH2NNAQ/ke17ZwdGBToddI8pDm48kK60W-ob1oA2Fm-j4E_9NQB7gQa3H78H3Y0txjaiv_0fDoOvxcdMmMKkDsyUqMSsMWxHk725yiiHCCLfrh8O1z4YTzHvnKhyp6Da-NYroOW3ZGjoBKy3azqku80C789l0kD6Ec8Uq9YczfrzwR7e2Mh5VMMOxnTbph8FXiclivDQnof69TlCeE0rAhj6HUpXkw/IMG_5736.JPG?format=1500w)

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588022779123-GCKZF7ZM5NHJ1KXAMW8D/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/0.jpeg?format=2500w)
Title: Re: Single Channel AB763 project
Post by: shooter on April 27, 2020, 04:56:14 pm
 :thumbsup:

like the braided grounds !
and that mini tranny  :laugh:
great workmanship as always!
Title: Re: Single Channel AB763 project
Post by: tubeswell on April 27, 2020, 05:15:26 pm
Are you using one of the Allen amp schematics by any chance (Old Flame)?
Title: Re: Single Channel AB763 project
Post by: p2pAmps on April 27, 2020, 08:48:21 pm
Are you using one of the Allen amp schematics by any chance (Old Flame)?

I am not Tubeswell, I did buy a PT from D Allen but I've never have seen his schematics.  This is one I put together and had Doug make a board for me from my DIYLC app.  Just kinda doing my own thing on this but I am guessing this has been done many times before :).
Title: Re: Single Channel AB763 project
Post by: p2pAmps on April 27, 2020, 08:49:17 pm
:thumbsup:

like the braided grounds !
and that mini tranny  :laugh:
great workmanship as always!

Thanks Shooter!  Yeah that little baby PT only weighs 10 lbs!

Title: Re: Single Channel AB763 project
Post by: sjwood3 on April 28, 2020, 03:18:04 am
Is there an instructional out there on how to do a similar ground buss?  I looks amazing.  I don't love the idea of grounding to the back of the pot.   I'm at that stage in rebuilding an amp as we speak! 
Title: Re: Single Channel AB763 project
Post by: p2pAmps on April 28, 2020, 09:11:02 am
Is there an instructional out there on how to do a similar ground buss?  I looks amazing.  I don't love the idea of grounding to the back of the pot.   I'm at that stage in rebuilding an amp as we speak!

Check out the Aiken's site on grounding.  Basically that bus connects with a bolt through the chassis directly in front of the inputs.  The only thing I ground on the bus are the pots.  There are also other tabs at that point where the bus is connected for other things like Cathode caps, reverb transformer, filter caps (except #1).  At the other side of the chassis next to your PT is where I ground #1 filter cap, power tube cathodes, artificial center tap, transformer, bias supply.  I ground the AC mains by itself.

So far (knock on wood) it's worked out well for me but I am WIDE open for other thoughts and improvements.

Cheers,
Title: Re: Single Channel AB763 project
Post by: mresistor on April 28, 2020, 05:08:53 pm
Very nice..  I did one of these single channel AB763s (DR) too, fun. Mine was flipped upright like a Marshall   I did mine from scratch.   I really like the blue paint on the endbells..   very nice touch. 
Title: Re: Single Channel AB763 project
Post by: DummyLoad on April 28, 2020, 08:08:36 pm
there is probably a reason the reverb transformer is turned 45deg. offset from parallel/perpendicular planes on all the blackface and silver face fender combo amps with reverb.  :dontknow:   

my thoughts are by rotating the transformer 45deg., fender is keeping the winding window eddy currents from firing directly into the driver tube and recovery tube.



--pete
Title: Re: Single Channel AB763 project
Post by: mresistor on April 28, 2020, 08:29:50 pm
Interesting Pete  now I will look at mine to note orientiation of the reverb transformer

Title: Re: Single Channel AB763 project
Post by: p2pAmps on April 29, 2020, 08:34:31 am
there is probably a reason the reverb transformer is turned 45deg. offset from parallel/perpendicular planes on all the blackface and silver face fender combo amps with reverb.  :dontknow:   

my thoughts are by rotating the transformer 45deg., fender is keeping the winding window eddy currents from firing directly into the driver tube and recovery tube.



--pete

Hey Pete,

I thought about that aspect but thought I would try it this way and see what happens, kind of an experiment.  When I did research on the subject of verb transformers the consensus was Fender did the angled tranny for space reasons.  Others say they have done what I did without any issues at all.  I think some Marshalls did the same but not 100% sure on that.  This is a sort of journey for me to see what I can and can't do and what is fact and what is speculation.  At the end I want a killer sounding amp for both Steel guitar and standard guitar too.  Filling her full of Jensens is also an experiment as I have to know LOL...

In Progress
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588167210598-GP1Z062FT32OY9J4X8UW/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/Front+Panel.JPG?format=2500w)

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588167210459-ZUVYCX98WKNHZYRUTSON/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/IMG_5742.jpeg?format=2500w)
Title: Re: Single Channel AB763 project
Post by: NewYorker on April 29, 2020, 09:51:37 am
I couldn't help noticing the solid copper connecting your Reverb Mix pot to the ground bus.  I assume you did that for structural reasons, i.e. to keep the wobbly end of the bus from wobbling?

Ed
Title: Re: Single Channel AB763 project
Post by: p2pAmps on April 29, 2020, 09:56:14 am
I couldn't help noticing the solid copper connecting your Reverb Mix pot to the ground bus.  I assume you did that for structural reasons, i.e. to keep the wobbly end of the bus from wobbling?

Ed

BINGO, looking to keep the bus from moving around...
Title: Re: Single Channel AB763 project
Post by: NewYorker on April 29, 2020, 12:21:09 pm
Phew!  I got one right today.

Ed
Title: Re: Single Channel AB763 project
Post by: Willabe on April 29, 2020, 01:51:22 pm
Very nice work Mike as always.  :icon_biggrin:

Waiting to hear what you think of the Jensen paper/oil caps.

(Sent you a PM.)
Title: Re: Single Channel AB763 project
Post by: jojokeo on April 29, 2020, 03:00:18 pm
Is there an instructional out there on how to do a similar ground buss?  I looks amazing.  I don't love the idea of grounding to the back of the pot.   I'm at that stage in rebuilding an amp as we speak!

Check out the Aiken's site on grounding.  Basically that bus connects with a bolt through the chassis directly in front of the inputs.  The only thing I ground on the bus are the pots.  There are also other tabs at that point where the bus is connected for other things like Cathode caps, reverb transformer, filter caps (except #1).  At the other side of the chassis next to your PT is where I ground #1 filter cap, power tube cathodes, artificial center tap, transformer, bias supply.  I ground the AC mains by itself.

So far (knock on wood) it's worked out well for me but I am WIDE open for other thoughts and improvements.

Cheers,

Hi Mike!
I've always paid close attention with my grounding schemes. It really is a learned part of building that people only learn about once they deal with their issues from not understanding it. I draw an analogy to boating (in the ocean, not lakes or rivers) where people just want to focus on the sailing and destination aspects. But once there, they realize that they have to find a way to securely stay somewhere, lol and there's no mooring or docking available nearby. So they need to anchor. There's many books that focus on just this one aspect. I think proper grounding, along with layout, is like a dirty little secret to success most just don't quite get? It's not sexy, doesn't have gain stages and special switching...so with most it's who cares? With all this I'll just say don't mix signal grounds with chassis grounds. Signal grounds are a return path for the signal and leave it at that.
Did you or do you ever use the listening device test when you place your iron (the OT at least)? If I don't place my OT on the other side of the chassis (usually the case) then I always do this before drilling any holes...
Title: Re: Single Channel AB763 project
Post by: shooter on April 29, 2020, 03:15:54 pm
Quote
PT only weighs 10 lbs!

If you need an 11 lb choke for balance, let me know  :laugh:
Title: Re: Single Channel AB763 project
Post by: DummyLoad on April 29, 2020, 06:16:33 pm
wondering if insulated terminals/standoffs would do a better job of support for you than the lugs of potentiometers. 

https://www.dropbox.com/s/lv69ay14j95rt56/20200429_150017.jpg?dl=0 (https://www.dropbox.com/s/lv69ay14j95rt56/20200429_150017.jpg?dl=0)

keystone electronics & cambion mfg. them. available from mouser, et-al. prices range from $4 to $12+

--pete
Title: Re: Single Channel AB763 project
Post by: p2pAmps on April 30, 2020, 07:09:48 am
wondering if insulated terminals/standoffs would do a better job of support for you than the lugs of potentiometers. 

https://www.dropbox.com/s/lv69ay14j95rt56/20200429_150017.jpg?dl=0 (https://www.dropbox.com/s/lv69ay14j95rt56/20200429_150017.jpg?dl=0)

keystone electronics & cambion mfg. them. available from mouser, et-al. prices range from $4 to $12+

--pete

Thanks Pete!  I like those stand offs but a little short for my project.  I can certainly make some however.  Good tip - Thanks!
Title: Re: Single Channel AB763 project
Post by: p2pAmps on May 01, 2020, 07:06:36 am
Getting very close now.  Waiting on a few of that last caps I wanted for this and she will be ready to start the startup procedure.  Then on to the table saw for cabinet making.

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588334562558-LYTJ2EHYF1ASTJU4Q9MB/ke17ZwdGBToddI8pDm48kCeRIHT5pOFXPhWTuzqDpWd7gQa3H78H3Y0txjaiv_0fDoOvxcdMmMKkDsyUqMSsMWxHk725yiiHCCLfrh8O1z5QHyNOqBUUEtDDsRWrJLTmv1ihXzK27xJYOPbUG3fJT24FqVKrTHasujL9zw2i7KXTMFFyH8WiFCX_TCHrC-ES/34.jpeg?format=1500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588334562670-2TG59IEKEZR5QDQJ6BOL/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/33.jpeg?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588334563441-OYG3N09DAMBAA0T1CL18/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/32.jpeg?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588334563678-2DGWIGIF4UTEUIBJ8GS7/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/31.jpeg?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588334564708-878QS7UM1RKIAHPBBPZE/ke17ZwdGBToddI8pDm48kCeRIHT5pOFXPhWTuzqDpWd7gQa3H78H3Y0txjaiv_0fDoOvxcdMmMKkDsyUqMSsMWxHk725yiiHCCLfrh8O1z5QHyNOqBUUEtDDsRWrJLTmv1ihXzK27xJYOPbUG3fJT24FqVKrTHasujL9zw2i7KXTMFFyH8WiFCX_TCHrC-ES/30.jpeg?format=1500w)
Title: Re: Single Channel AB763 project
Post by: p2pAmps on May 03, 2020, 05:58:25 am
This is the completed chassis for my latest beast. This amp is based on the famous AB763 with some twists.  One Channel, No Tremolo Circuit, Presence Control, Modified Tone Stack, Reverb (Dwell, Mix, and Tone Controls) 1/2 Power switch, and Multi Impedance.  POI Jensen coupling caps throughout and F&T filter caps. 

First tests are great!  Very quiet and powerful.  The tone through my shop test 12" is big and bold.  I can't wait to hear this through a set of 12" quality speakers.

Next, I will get started on a 2x12 combo cabinet for her.

As always, thank for the interest and thanks to all the great folks on this forum.

Mike

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588503274401-Z4K45B05WYUDOG0FR91M/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/100.JPG?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588503276696-GZ01433I1BQ1CV5HGB79/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/109.JPG?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1588503272938-UHCR55L41LABQ2YMZ4QN/ke17ZwdGBToddI8pDm48kCeRIHT5pOFXPhWTuzqDpWd7gQa3H78H3Y0txjaiv_0fDoOvxcdMmMKkDsyUqMSsMWxHk725yiiHCCLfrh8O1z5QHyNOqBUUEtDDsRWrJLTmv1ihXzK27xJYOPbUG3fJT24FqVKrTHasujL9zw2i7KXTMFFyH8WiFCX_TCHrC-ES/6.JPG?format=1500w)
Title: Re: Single Channel AB763 project
Post by: shooter on May 03, 2020, 08:08:04 am
beautiful work of art and function !!
I'm amazed at the number of artists here with an engineering mind  :m17
Title: Re: Single Channel AB763 project
Post by: Willabe on May 03, 2020, 11:14:45 am
Looks great Mike.  :icon_biggrin:

Did you polish/buff the B+ filter caps dog house?
Title: Re: Single Channel AB763 project
Post by: echuta13 on May 03, 2020, 01:51:37 pm
 :worthy1: VERY nice work!!! 
Title: Re: Single Channel AB763 project
Post by: pdf64 on May 03, 2020, 02:51:15 pm
Looks great, well done!
Assuming that the presence control is of the standard type, ie in the power amp NFB loop, I'd advise against putting it back there by the vol control. As output circuits close by inputs/early stages can give rise to stability problems.
Hopefully you'll get away with it  :icon_biggrin:
Title: Re: Single Channel AB763 project
Post by: dude on May 03, 2020, 03:00:47 pm
That's about the cleanest build I ever seen, you're an artist p2p. Bet your cab will outstanding too. :worthy1:
Title: Re: Single Channel AB763 project
Post by: p2pAmps on May 04, 2020, 08:54:51 am
Looks great Mike.  :icon_biggrin:

Did you polish/buff the B+ filter caps dog house?

I did because I am basically insane LOL
Title: Re: Single Channel AB763 project
Post by: p2pAmps on May 04, 2020, 08:57:23 am
Looks great, well done!
Assuming that the presence control is of the standard type, ie in the power amp NFB loop, I'd advise against putting it back there by the vol control. As output circuits close by inputs/early stages can give rise to stability problems.
Hopefully you'll get away with it  :icon_biggrin:

Thank you.  Yes it is in the NBF loop and apparently I did get away with it as it works perfectly and the amp is VERY quiet (so far).  I appreciate your feedback and I will take a deeper look at what you are suggesting.

Cheers!

Title: Re: Single Channel AB763 project
Post by: p2pAmps on May 04, 2020, 08:57:57 am
That's about the cleanest build I ever seen, you're an artist p2p. Bet your cab will outstanding too. :worthy1:

Thank you Dude! 
Title: Re: Single Channel AB763 project
Post by: Willabe on May 09, 2020, 08:10:57 am
Mike, how do those paper -n- oil caps sound to you?
Title: Re: Single Channel AB763 project
Post by: p2pAmps on May 10, 2020, 09:57:02 pm
Mike, how do those paper -n- oil caps sound to you?

I'll let you know soon as I finish up the cab.  I don't want to make any assumptions till I get her in the cab with decent speakers.  Soon I hope, been spending the last 3 days spring cleaning the shop and boy do I feel old (hurting everywhere hahaha)

Title: Re: Single Channel AB763 project
Post by: pdf64 on May 11, 2020, 03:37:16 am
Looks great, well done!
Assuming that the presence control is of the standard type, ie in the power amp NFB loop, I'd advise against putting it back there by the vol control. As output circuits close by inputs/early stages can give rise to stability problems.
Hopefully you'll get away with it  :icon_biggrin:

Thank you.  Yes it is in the NBF loop and apparently I did get away with it as it works perfectly and the amp is VERY quiet (so far).  I appreciate your feedback and I will take a deeper look at what you are suggesting.

Cheers!
I was reminded about RG Keen’s excellent page on the topic (thanks shooter!) http://www.geofex.com/Article_Folders/lead_dress/lead_dress_in_tube_amps.htm
Title: Re: Single Channel AB763 project
Post by: p2pAmps on May 17, 2020, 05:44:04 pm
Ok, here is a fun little sound clip.  I'm still working on the cab but this is what she will be like.


Title: Re: Single Channel AB763 project
Post by: Ed_Chambley on May 21, 2020, 08:52:57 am
Great build.  Perfect for one of those jacked up Hawaiian geetars.  What kind of music do you play with one of those steel geetars.  Someone told me it was an outdated instrument and some have 2 necks, but I have never even seen one with even one neck.


I got a buddy named emmons says he can play anything with strings, hell add a couple more and call it Bakersfield.


Really nice and over the top build.  Bout par for the course for P2P amps ain't it.


Just funniness, very nice and clean amp.
Title: Re: Single Channel AB763 project
Post by: Dave on May 21, 2020, 04:26:54 pm

Very nice build. I am very envious of those who can keep their builds looking pretty. I have built a lot of great amps, but none have ever looked pretty like that. I also have two cents to throw at the grounding conversation. I have yet to find a fail safe grounding scheme. I have tried them all and have had great success with just doing it like Leo Fender did it. But, occasionally, a ground loop pops up and drives me crazy while I try to figure it out. The last one that I encountered was the cathode resistor/bypass cap of the reverb recovery stage was moaning and groaning. After I tracked it down, I found that I could literally ground it anywhere on the amp except for the place I had it grounded.


Dave
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 01, 2020, 02:00:42 pm
We have twins now :)

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1591037889661-S2WGPFSEKWIHP81ATBWU/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/Bad+Dawg+Twins+1.JPG?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1591037890031-46W96OGMAIT5DXTUL5BG/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/Bad+Dawg+Twins+2.JPG?format=2500w)
Title: Re: Single Channel AB763 project
Post by: kagliostro on June 01, 2020, 02:09:49 pm
 :thumbsup: :thumbsup: :thumbsup:

VERY NICE

Franco
Title: Re: Single Channel AB763 project
Post by: sluckey on June 01, 2020, 02:24:35 pm
Twins squared. Is hat like a Quad?    :icon_biggrin:
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 01, 2020, 02:45:45 pm
Twins squared. Is hat like a Quad?    :icon_biggrin:

2*2^=x. solve for x hahaha
Title: Re: Single Channel AB763 project
Post by: brewdude on June 02, 2020, 11:33:11 pm
I like the ground buss.  I’ve never seen (or noticed) the signal wires being tied to the ground bus.

I am working (painfully slowly) on build where I used a vertical terminal strip to hold the far end of the bus.
Title: Re: Single Channel AB763 project
Post by: shooter on June 03, 2020, 05:48:14 am
Quote
2*2^=x. solve for x hahaha

(X = 2 full stacks + AB/Y + amp volume 8) - long term hearing :icon_biggrin:
Title: Re: Single Channel AB763 project
Post by: SILVERGUN on June 03, 2020, 09:03:09 am

Mike, you've created quite a conundrum for me.
I can either spend more time trying to make my amps look and sound as good as yours OR practice playing guitar so I can someday play as well as you or your pedal steel partner.
Either way, It's a steep hill to climb. How am I ever supposed to get a shed built?

 :thumbsup:
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 03, 2020, 09:04:29 am
I like the ground buss.  I’ve never seen (or noticed) the signal wires being tied to the ground bus.

I am working (painfully slowly) on build where I used a vertical terminal strip to hold the far end of the bus.

Nice work Brewdude and good idea on your ground bus for sure. 

Cheers!
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 03, 2020, 09:05:28 am

Mike, you've created quite a conundrum for me.
I can either spend more time trying to make my amps look and sound as good as yours OR practice playing guitar so I can someday play as well as you or your pedal steel partner.
Either way, It's a steep hill to climb. How am I ever supposed to get a shed built?

 :thumbsup:

HAHA, thanks!  If it's a she-shed let she build it :)
Title: Re: Single Channel AB763 project
Post by: DummyLoad on June 03, 2020, 01:09:33 pm
thinking about using the method in the attached photo.


--pete
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 04, 2020, 08:30:47 am
thinking about using the method in the attached photo.


--pete

I like it Pete
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 11, 2020, 05:29:18 pm
Here's the final on this 2x12.  Holy moly is this amp loud!  Should be a big hit with the steel guitar and tele pickers. 

(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1591914452144-8CPKN2437CJXFF4CRCV6/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/40.JPG?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1591914452311-XQ35EF2R6BAB1XGBJHRB/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/41.JPG?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1591914453511-YNSPC5IHYNUOM4QV8KIQ/ke17ZwdGBToddI8pDm48kL3VKmwKI3leYB51VJjLFB8UqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcgK5SGg9Ovb1yloBBOHcruw_mYLfAhRzzgArFCB07Dw0L8n4JypuoE5Tg6Wg5Oyvs/42.JPG?format=2500w)
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1591914453640-580WAAP8NALFJFZ8RZC7/ke17ZwdGBToddI8pDm48kCeRIHT5pOFXPhWTuzqDpWd7gQa3H78H3Y0txjaiv_0fDoOvxcdMmMKkDsyUqMSsMWxHk725yiiHCCLfrh8O1z5QHyNOqBUUEtDDsRWrJLTmv1ihXzK27xJYOPbUG3fJT24FqVKrTHasujL9zw2i7KXTMFFyH8WiFCX_TCHrC-ES/44.jpeg?format=1500w)
Title: Re: Single Channel AB763 project
Post by: vampwizzard on June 11, 2020, 09:21:15 pm
AMAZING. is that p2p illuminated in the front?

Seriously nice build start to finish.
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 11, 2020, 10:59:30 pm
AMAZING. is that p2p illuminated in the front?

Seriously nice build start to finish.

Yeah I lite that logo up for fun LOL...
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 11, 2020, 11:00:01 pm

A little steel guitar sound demo
Title: Re: Single Channel AB763 project
Post by: Willabe on June 11, 2020, 11:59:00 pm
So, what do you think of the Jensen paper in oil coupling caps?

Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 12, 2020, 07:23:32 am
So, what do you think of the Jensen paper in oil coupling caps?
Well I think they are pretty great and made a pretty big difference.  One thing I notice on this amp is the amount of tonal adjustment and clarity compared to a standard AB763 with say Malloy 150s.  Way more of everything comes through loud and clear.  Of course this is single channel and a stripped out trem but I'm not sure those changes would do what I describe here.  What ever it is its pretty great.  She is very quiet too which is always a blessing.  Those dang Jensens are big bucks but I had to know.  Its like riding a Harley, once you do it you have to have one HA!

Cheers
Title: Re: Single Channel AB763 project
Post by: Willabe on June 12, 2020, 02:41:28 pm
Thanks Mike.   :icon_biggrin:

I may have to try those.  :undecided:
Title: Re: Single Channel AB763 project
Post by: p2pAmps on June 13, 2020, 11:51:37 am
Thanks Mike.   :icon_biggrin:

I may have to try those.  :undecided:

I'm glad I tried them as I found out first hand the difference.  Not saying that will be the norm from now on but I will certainly use Jensens on special projects.