Output Jack Wiring

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riley0
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Output Jack Wiring

Post by riley0 »

I see parallel output jack wiring used on all schems here?
I don't intend using more than one speaker cabinet.

Is it possible safely use rotary 4,8,16 to one socket with 5w resistor as pic
Or is there a safer better alternative?
Last edited by riley0 on Sat 12/02/23 4:37 am, edited 1 time in total.
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JMPGuitars
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Re: Output Jack Wiring

Post by JMPGuitars »

Why do you want the resistor there at all? That's not necessary.

The parallel jacks don't change the impedance. What you connect to them does.

Skip the resistor, and wire with the 2nd jack omitted. Then match your impedance switch to the speaker connected.
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riley0
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Re: Output Jack Wiring

Post by riley0 »

Read somewhere resistor acts as safety should speaker be disconnected.
Would the pic below work using none shorting cliff?

I really want the protection when no load..
Last edited by riley0 on Sat 12/02/23 4:37 am, edited 1 time in total.
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Re: Output Jack Wiring

Post by JMPGuitars »

As long as the pins are correct, yes.

You could put a higher wattage resistor in parallel with the jack (it has to be much higher). It will affect the sound. You would then need to match impedance based on the combination of the speaker and resistor in parallel.

If it were a valuable trick, you would see it frequently, but there's a reason you don't.

My suggestion: don't unplug the speaker!
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Re: Output Jack Wiring

Post by riley0 »

Ok thanks for info.
So what are the benefits of parallel? Will the 4 ohm winding become usable as 8 if I'm thinking correctly..Can't find much info on wiring examples...
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Re: Output Jack Wiring

Post by JMPGuitars »

riley0 wrote:
Thu 11/30/23 12:23 pm
Ok thanks for info.
So what are the benefits of parallel? Will the 4 ohm winding become usable as 8 if I'm thinking correctly..Can't find much info on wiring examples...

Two Resistors of equal value:
In parallel, half the stated value (8 + 8 = 4)
In series, add stated values (8 + 8 = 16)

You can do an internet search for the opinions on tone of parallel vs serial speaker wiring. If you're only wiring one speaker, then it's irrelevant.

I wire things differently based on the amount of speakers and target impedance. If you're wiring two speakers, in parallel the benefit is that if one speaker dies or becomes disconnected, one speaker will still work.

If I wire 4 speakers, I'd go with 2 pairs each wired in series, and then wire the pairs together in parallel, assuming that they're all 16Ω (16Ω is ideal for 18W transformers).
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Re: Output Jack Wiring

Post by riley0 »

Diagram I posted above is wired wrong, just in case anyones looking in...Center goes to tip, OT ground to cliff
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Re: Output Jack Wiring

Post by JMPGuitars »

riley0 wrote:
Fri 12/01/23 11:57 am
Diagram I posted above is wired wrong
I did hint at that 😉:
JMPGuitars wrote:
Wed 11/29/23 5:16 pm
As long as the pins are correct, yes.
Here's the correct wiring from one of my layouts:
Output Switch Wiring.jpg
Thanks,
Josh
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