Is it acceptable to 'jumper' speaker wire through a switch? | on ElectriciansForums
Guest viewing is limited

Discuss Is it acceptable to 'jumper' speaker wire through a switch? in the Electrical Engineering Chat area at ElectriciansForums.net

ChrizK

DIY
Joined
Dec 14, 2022
Messages
26
Reaction score
13
Location
UK
Firstly, I hope it is ok to discuss the wiring of speakers here. TBH my ignorance in all things electrical knows no bounds, and I am guessing it is a discussion about ohms, of which I have less idea about than watts.
To that end, I would appreciate any responses in the simplest of terms. Once again, I apologise if this is the wrong forum, as I suspect it is attended by many large brains that would rather speak in 'scientific' terms. However, my question is more 'theory' rather than 'straight electrical'.

The question relates to using a sound system with a TV on one wall which is perpendicular to a projector screen on another. The TV has Front Left and Front Right speakers located above it ...the idea is to 'switch' the Front Right to becoming Front Left (the projector), and Front Left to a separate speaker.
I bought a two-way speaker switch box from Amazon. I guess it is obvious to say that this is normally used to switch the input to two pairs of output.
In my case, I have speaker cable running to a single speaker on Pair(1) Right BUT ALSO 'jumpering' to Pair(2) Left.
As you may surmise, Pair(1) Left goes to a speaker, and Pair(2) Right goes to a speaker ...so three speakers in total.

If I think of this as 'direction of flow' when I select Pair(1), the Input(amp) is directed to Pair(1) Right speaker, and is 'dead ended' to Pair(2).
I turn off Pair(1) and select Pair(2), in which case, Input(amp) is directed to Pair(2) Left speaker, and Pair(2) Right jumpered to the twisted/join in Pair(1) speaker.

Hopefully I have explained that well enough (don't think a picture would actually provide any clarity)

This works ...but, sometimes my speakers just 'cut out'. Strangely (and please don't shout at me), if I increase the volume on the TV, it suddenly comes on and I deafened until I quickly turn the volume down. My initial theory was that it was the amp cutting out, but I considered that turning the volume up shouldn't resolve the problem, and so I believe it to be the switch.

So, my question is 'could this be considered a legitimate use of the switch, or am I doing something so stupid that I should expect it to cut-out?'

Thanks for your time.
 
As an Amazon Associate Electricians Forums may earn a small commission from qualifying purchases.
If turning the volume up cures it then I'd hazard a guess at a loose connection somewhere.
In my ignorance, I was thinking along the same lines. Given that the speaker wire is just terminated into standard 'grips', I was thinking that it is possibly an internal fault with the switch. However, I was concerned that I was causing my own problem by attempting to do something that was fundamentally 'silly'.

The switch does allow Pair(1) and Pair(2) to be selected, ie both on. I suspect this might cause issues and so I have put a note on it to say switch both off first, before selecting the required pair. Not wishing to blow a speaker ...or even the amp(?), I have never tried having them both on.
Theoretically (appreciating that you have to visualise what I am attempting), could I damage the speaker or amp by having both pairs 'on'?
 
The main way any damage could be done when combining speakers is if you have multiple speakers wired in parallel and it reduces the impedance (resistance to all intents and purposes in this case) to a value lower than the amplifier can handle. This could damage the amplifier.
 
The main way any damage could be done when combining speakers is if you have multiple speakers wired in parallel and it reduces the impedance (resistance to all intents and purposes in this case) to a value lower than the amplifier can handle. This could damage the amplifier.
If my diagram is sufficient, is that effectively what I am doing?
Given the switch allows both pairs to be 'on', would it also result in the reduction in impedance you mention?
Or, could it actually enhance it and negate the problem?
If so, given my 'misuse' of the switch, could it make things better or worse?

TBH This is where Ohms start to lose me ...why the reduction can cause damage ... although your wording perhaps has given me a clue. Is it that having more and more speakers reduces the resistance, so 'more gets through'? Again, I am not totally sure 'of what' ...is it equivalent to more 'power' getting through, and therefore the much spoken about 'blowing up the amp'?
 
I still can't quite picture what exactly you are trying to achieve with the whole left/right/crossing/whatever. But you don't want to connect the left speaker output of the TV with the right speaker output.

I'm pretty certain you won't need a speaker switch box either, as you are wanting it set up permanently - you don't need any switching. The worse you may need is a couple of dummy load resistors I reckon.
 
Ah I see. No, don't connect the two speaker switch outputs together. That is what will be causing your problem.
Oh ... :(
I know I asked not to have a technical explanation, but would you mind explaining a bit more?
ie, why does the sound cut out, and am I potentially damaging the amp or speaker?
Also, is there a reason why increasing the volume makes it come back (and does that too increase the risk of damage)?

Is it the case that there is no possible way to achieve what I want, other than having two pairs of speakers (resulting in two speakers right next to each other, which is what I wanted to avoid)?
 
...as you are wanting it set up permanently ...
Perhaps this is where the confusion is ...it isn't permanent. Either I will be watching TV with one pair, or the Projector with one 'switched' speaker + the additional speaker on the right of the projector. Hopefully that makes sense.
 
Perhaps this is where the confusion is ...it isn't permanent. Either I will be watching TV with one pair, or the Projector with one 'switched' speaker + the additional speaker on the right of the projector. Hopefully that makes sense.

Ah sorry, I didn't quite grasp that bit.

However you do this, you can't cross connect the left output with the right output. That will be why you have the cutting our problem.

I would reconsider to be honest - for the best sound results you want a matching pair of speakers in use and positioned properly, especially when you are using the projector. Also then you could use your switch box as it is intended.

The 'technical' reason is that you are interconnecting the outputs of two separate amplifier circuits. They designed to feed two separate speaker loads.
 
However you do this, you can't cross connect the left output with the right output. That will be why you have the cutting our problem.

Unless ive misunderstood that switch box selects between pair 1 or pair 2. So as its drawn a cross connection doesn't happen because only on of the linked sets of terminals will ever be connected to the amp.

If it was a cross connection it shouldn't work at all, not just cut out after a while.
 

Reply to Is it acceptable to 'jumper' speaker wire through a switch? in the Electrical Engineering Chat area at ElectriciansForums.net

Similar threads

  • Question
Ah yes my apologies, thank you much appreciated.
Replies
5
Views
964
Just doing some thread admin :)
Replies
1
Views
865

Recommended Sponsor News

Exclusive Forum Offer! Free euro 2024 wall chart for first 10 responses!

Hi everyone,

We have 10 exclusive Uheat EURO 2024 Wallcharts to giveaway for Electricians Forum Members! The first 10 people to reply YES to this thread - I will message and get them sent out to you just in time for this years tournament! GO GO GO

Quickwire Now Sponsor ElectriciansForums.net

I am sure you will join me in welcoming our newest sponsors of ElectriciansForums.net - Quickwire! They have decided to join us after seeing you guys discussing their products here. Now we have an expert on board that you can chat to @Quickwire-Sam who will be happy to answer your queries!

[ElectriciansForums.net] Quickwire Now Sponsor ElectriciansForums.net


@Quickwire-Sam said "At Quickwire, we're all about speed, safety, and reliability. We're a family-run business, and every Quickwire connector is proudly made right here in the UK, ensuring noticeable quality. In short, Quickwire is the fastest connection method on the market. Whether you're an experienced electrician or a DIY enthusiast, Quickwire makes electrical connections ridiculously quick and easy. We're passionate about blending British craftsmanship with innovation. If you have any questions or if there's any way we can help, please just ask me!"

PCBWay Now Sponsor ElectriciansForums.net!!

I hope you will all join me in welcoming our newest sponsor to the forum PCBWay! You can contact their friendly people by sending a message to @PCBWay who will be happy to answer your queries.

Welcome to the community and thanks for your sponsorship!

[ElectriciansForums.net] PCBWay Now Sponsor ElectriciansForums.net!!

PCBWay provides services including PCB Prototype and batch Production, PCB Assembly (SMT), 3D Printing, CNC Machining, PCB Design, Electronics Modules Selling, etc. We are committed to meeting the needs of global makers from different industries in terms of quality, delivery, cost-effectiveness, and any other demanding requests in electronics.

[ElectriciansForums.net] PCBWay Now Sponsor ElectriciansForums.net!!

Search Electricans Forums by Tags

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

YOUR Unread Posts

This website was designed, optimised and is hosted by untold.media Operating under the name Untold Media since 2001.
Back
Top