Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Garrett335 on February 16, 2018, 12:07:27 pm

Title: Wiring double Speaker output jacks on amplifier
Post by: Garrett335 on February 16, 2018, 12:07:27 pm
Hey guys,
I searched for an answer for this question but did not find one.
I'm wondering how you wire the speaker output jacks if you want to run two separate cabinets.
My OT has a 4 / 8 /16 taps, how would I wire it to be able to run two 8 ohm cabs?  Do I just take the 8ohm tap and run it in series with the other jack?
And my second part of the question, if I plug two 8 ohm cabs in to the 8 ohm tap in series like my drawing, doesn't the amplifier see a different load other than 8?
Thanks in advance you guys are awesome and any help is appreciated.
Title: Re: Wiring double Speaker output jacks on amplifier
Post by: sluckey on February 16, 2018, 12:42:59 pm
I would connect the 4, 8, and 16Ω taps to an impedance selector switch. Hoffman sells a good one. Then connect the output of the switch to two speaker jacks wired parallel. When you connect your two 8Ω cabs to the two speaker jacks set the switch to the 4Ω position.
Title: Re: Wiring double Speaker output jacks on amplifier
Post by: a90s2cs on February 16, 2018, 12:48:12 pm
That's exactly what I was thinking,  two 8ohm cabinets would equal a combined 4ohm when connected to output jacks wired in parallel.  So you would use the 4ohm tap for this.
Title: Re: Wiring double Speaker output jacks on amplifier
Post by: a90s2cs on February 16, 2018, 01:03:08 pm
If you don't want a switch, you would wire up the 4ohm taps to 2 jacks in parallel and you could label it like this...
Title: Re: Wiring double Speaker output jacks on amplifier
Post by: Garrett335 on February 16, 2018, 01:32:23 pm
Quote from: sluckey on February 16, 2018, 12:42:59 pm
I would connect the 4, 8, and 16Ω taps to an impedance selector switch. Hoffman sells a good one. Then connect the output of the switch to two speaker jacks wired parallel. When you connect your two 8Ω cabs to the two speaker jacks set the switch to the 4Ω position.
Thank you Sluckey! I'll look into this.

Also one last question, I'm green so take it easy on me.
How to do you wire a cliff jack in series or parallel?
I've attached a photo is this correct?
Title: Re: Wiring double Speaker output jacks on amplifier
Post by: Garrett335 on February 16, 2018, 01:36:24 pm
Quote from: a90s2cs on February 16, 2018, 01:03:08 pm
If you don't want a switch, you would wire up the 4ohm taps to 2 jacks in parallel and you could label it like this...

Thank you for the drawing! This is a great route to go as well
Title: Re: Wiring double Speaker output jacks on amplifier
Post by: sluckey on February 16, 2018, 01:43:39 pm
Both of those drawings are parallel. There is no reason for you to try to wire speaker jacks on an amp in series.
Title: Re: Wiring double Speaker output jacks on amplifier
Post by: Garrett335 on February 16, 2018, 03:55:44 pm
Quote from: sluckey on February 16, 2018, 01:43:39 pm
Both of those drawings are parallel. There is no reason for you to try to wire speaker jacks on an amp in series.

Okay, thanks so much!