First Dumble from scratch

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philbard
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First Dumble from scratch

Post by philbard »

So, I finally feel that I've logged enough time modding my CTone kit OTS 50w, its sounding much better than when I started out. Now on to building another 102 from scratch sourcing my own parts, this time 100w. I have a chassis from Taylor and most all of the components at this point, yikes sourcing parts is more work than building the actual amp. Anyways, I'll post up some build photos as I go along and would of course appreciate any feedback from the forum. I'm working off Tony's "adapted 102" layout and also one that Vertigo made up that is almost the same. I'm planning to put the FET on the foot switch in place of the PAB, I'm not a fan of the PAB sound so will relegate it to a switch somewhere.One question off the bat, I notice the ground for the foot switch plug running all the way around to the voltage regulator. Is this advantageous and if so does have to do with ground loops?

Taking my time, here is where I'm at so far. Awaiting a few more items from AES and Mouser (Mouser is incredibly slow right now for some reason).
IMG_6922.jpg
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Phil
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Vertigo
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Re: First Dumble from scratch

Post by Vertigo »

You didn't waste any time getting started. Nice work. Nice chatting with you the other day too. Once we can all stay safe once again, we'll have to get together.
Sean Chaney
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philbard
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Re: First Dumble from scratch

Post by philbard »

Vertigo wrote: Tue Mar 09, 2021 5:20 pm You didn't waste any time getting started. Nice work. Nice chatting with you the other day too. Once we can all stay safe once again, we'll have to get together.
Yes, great to meet you and see your shop and bikes, gorgeous work. Transformers fit great, had to adjust 2 holes on the OT but no big deal.
Phil
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philbard
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Re: First Dumble from scratch

Post by philbard »

Going with Martin's footswitchable FET, with the PAB relegated to a toggle switch (on the far left, first photo). Still waiting on a few more parts and the 12v transformer before I can mount the remaining boards but after that it will probably go fast. One thing I've learned about ordering electrolytics for the boards is to make sure you check the physical length of the cap your ordering first, ended up with a few that were too big to fit on the boards. :oops:
Switches.jpg
Boards.jpg
Relay PS is finished and installed
Relay PS.jpg
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Phil
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philbard
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Re: First Dumble from scratch

Post by philbard »

Power boards finished up, only thing remaining is the preamp board and the FET. Totally fun...
Power Boards Installed.jpg
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Phil
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Chris Brown
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Re: First Dumble from scratch

Post by Chris Brown »

Nice work!! Since you are doing fet on a footswitch you might consider mounting the fet level control in the fet input hole. I did this on my 102 build and it has turned out to be very useful on stage.
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dbharris
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Re: First Dumble from scratch

Post by dbharris »

Looking good!

-Dan
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philbard
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Re: First Dumble from scratch

Post by philbard »

Chris Brown wrote: Tue Mar 16, 2021 1:14 am Nice work!! Since you are doing fet on a footswitch you might consider mounting the fet level control in the fet input hole. I did this on my 102 build and it has turned out to be very useful on stage.
Yes, doing that very thing, but thanks for the suggestion. Really like the idea of going to OD with the option of engaging FET as well...
Phil
ChopSauce
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Re: First Dumble from scratch

Post by ChopSauce »

Vertigo wrote: Tue Mar 09, 2021 5:20 pm You didn't waste any time getting started. Nice work.
Oh yes, very nice workmanship!
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philbard
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Re: First Dumble from scratch

Post by philbard »

Got the build finished today. No sound from it at first until I realized I'd failed to install the coax from the Volume pot to the V1B grid. Also had the wrong resistors on two of the PT cathodes so it was giving screwy bias readings. It's up and running and sounds really great, and I will credit all of you guys here who have helped me get to this point. Thanks a bunch...

OD channel is surprisingly smooth right off the bat, I've used some of Tony's mods and the 100w, vs the 50 I built before, may also be making a difference. On to building the cabinet and also probably another Dumbleator for it.

But seriously, I can quit at any time... :D
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Phil
Aaron
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Re: First Dumble from scratch

Post by Aaron »

Beautiful work Phil.

Now on to the next one :D

Aaron
talbany
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Re: First Dumble from scratch

Post by talbany »

Looks Great Phil!
Congrats & Enjoy
Tony
" The psychics on my bench is the same as Dumble'"
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norburybrook
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Re: First Dumble from scratch

Post by norburybrook »

great build :mrgreen:

that amp will serve you well for the rest of your life ;)



M
fred.violleau
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Re: First Dumble from scratch

Post by fred.violleau »

Superb build! Congrats!

Fred.
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Colossal
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Re: First Dumble from scratch

Post by Colossal »

Nice job and looks great!
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