Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Ariel tube fanatic on September 15, 2024, 04:56:25 pm

Title: Wiring mutiple taps different jacks
Post by: Ariel tube fanatic on September 15, 2024, 04:56:25 pm
Hello,

I have an ab763 clone with a multi tap ot, 2,4,8 i would like to wire.

I will not use the 2 ohm tap, i can just heat shrink it right ? And not connect to anything? And how so i go about the other jacks?

Connect each tap to a shorting jack (switch to gnd and tip is the tap?)

Thanks to anyone that would help
Title: Re: Wiring mutiple taps different jacks
Post by: tubeswell on September 15, 2024, 05:05:11 pm
Hello,

I have an ab763 clone with a multi tap ot, 2,4,8 i would like to wire.

I will not use the 2 ohm tap, i can just heat shrink it right ? And not connect to anything? And how so i go about the other jacks?

Connect each tap to a shorting jack (switch to gnd and tip is the tap?)

Thanks to anyone that would help


Depends on which type of AB763 amp, and which type of OT
Title: Re: Wiring mutiple taps different jacks
Post by: Ariel tube fanatic on September 15, 2024, 05:11:15 pm
Its a mojotone kit

Attached layout,

This ia the OT
Title: Re: Wiring mutiple taps different jacks
Post by: Willabe on September 15, 2024, 05:25:58 pm
I have an ab763 clone with a multi tap ot, 2,4,8 i would like to wire.

I will not use the 2 ohm tap, i can just heat shrink it right ? And not connect to anything? And how so i go about the other jacks?

Connect each tap to a shorting jack (switch to gnd and tip is the tap?)

Yes, just heat shrink the unused tap.

No, you can not use any shorting jacks.
Title: Re: Wiring mutiple taps different jacks
Post by: Ariel tube fanatic on September 16, 2024, 01:12:33 am
sorry link wasn't attached for a reason
this is the OT

https://www.mojotone.com/Blackface-Bassman-Super-Reverb-Vibroverb-Output-Transformer

the reason i can't use shorting jacks is because if i short one tap to gnd it basically shorts the entire secondary ? and if i use the aux as a 4 ohm tap i will get lower volume because the 8 ohm is grounded via the shorting jack?

thanks everyone, it's running in my head but i can't reach the answer fully, your replies help
Title: Re: Wiring mutiple taps different jacks
Post by: Latole on September 16, 2024, 07:01:47 am
You need to use only one ohms output.
Leave other not connected.

Look any Marshall amp with few OT output, you'll understand
Title: Re: Wiring mutiple taps different jacks
Post by: Willabe on September 16, 2024, 09:12:18 am
the reason i can't use shorting jacks is because if i short one tap to gnd it basically shorts the entire secondary?

Correct.

....and if i use the aux as a 4 ohm tap i will get lower volume because the 8 ohm is grounded via the shorting jack?

No.

It will short the entire secondary.

Title: Re: Wiring mutiple taps different jacks
Post by: tubeswell on September 17, 2024, 02:35:49 pm
If it’s an amp head, you could wire the switch lug of a tip-switch jack to a chunky wire-wound dummy load resistor (to ground) - for dummies who forget to plug a speaker in. (I.e. This would be for the main speaker tap)