Quick Speaker Question About OHM's

Brentradio

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I have a Dynamo HS-2 cut corner (23 3/4") jamma cab that has one 8 ohm speaker. There is wiring for another speaker. Can I just add another 8 ohm speaker?

Can I damage anything by doing that?

Or do I need two 4 ohm speakers?

Thanks!

Brent
 
If the wiring is already there for another speaker then there should be no problem installing that extra speaker.
 
The speaker wires on my cab just daisy chain off each other. In other words, only two wires are coming from the jamma harness, and they plug into the first speaker, and then daisy chain off to the other speaker, much like the ground wire in a control panel from button to button.
 
Sounds like the speaker wiring is for two mono speakers in parallel.

Just be sure your new speaker is 8 ohms. Most JAMMA boards can handle a 4 ohm load.
 
Ok, it's working perfectly and sounds great!

Thanks!

Such a big difference from one speaker to two...
 
Ok, it's working perfectly and sounds great!

Thanks!

Such a big difference from one speaker to two...

You might want to experiment with stero simulation devices to give you a different experince.

I have seen a devices ranging in from the low of 10 dollar that would push one set of frequencys to one side of the speakers and the rest to the other side.

In the past when I experimented with this stuff 20 years ago, you could tell that these devices were not true stero and the result were better than mono but not a stero experince. Today devices might be a bit better, your mileage may differ..
 
I have a Dynamo HS-2 cut corner (23 3/4") jamma cab that has one 8 ohm speaker. There is wiring for another speaker. Can I just add another 8 ohm speaker?

Can I damage anything by doing that?

Or do I need two 4 ohm speakers?

Thanks!

Brent

Ken stated that the board can handle a 4ohm load, but in practice it's not always good to add a second speaker. Normally, when dealing with an amplifier it's better to *increase* the resistance than to lower it.

If you hook up two 8 ohm speakers in parallel (daisy chain,) that drops the resistance by half to 4 ohms. This taxes the amplifier more since there's less resistance. But if you hook up two 8 ohms speakers in series, that doubles the resistance to 16 ohms, which will make it quieter but won't be as hard on the amplifier.

Sorry if this is stuff you already know...

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What are you driving the speakers with?

Depending on what amp is used on the PCB you're using, some are more flexible than others when it comes to load impedance. Ultimately it's the amp that determines what you can and can't do.

I can't speak for all amps, but the TDA2002/2003 commonly found on Atari AR's (and other PCBs and JAMMA adapters), can drive down to 1.6 ohms. So, you can use pretty much any speaker config with them.

I'd look up the datasheet for the audio power amp IC on whatever board you're using, and see what the rating says it can handle.
 
Just to clarify, here are examples of "series" and "parallel" wiring.

Series wiring raises the impedance of the speaker circuit, and this is an easier load for an amplifier to drive. Total sound output will generally be not as loud with this type of load. (Less output wattage)

series_wiring.png


Parallel wiring lowers the impedance of the circuit, this is a more difficult load for the amplifier to drive, some amplifiers are OK driving lower impedance, but there is always a limit. Sound output will generally be louder with this type of load. (more output wattage)

spkr_p.gif



Speakers are resistance loads, like a resistor. You could actually put a resistor in place of a speaker, problem is, it wouldn't make any sound, just heat.

Generally you don't want to test the load handling of an amplifier by just dropping the resistance of the speaker load until it blows, that is unless you have an infinite supply of amplifiers. :)

Hope this helps. Sorry the two examples are of not the same impedance speakers, but if the second example had 4 ohm speakers, the load to the amplifier would be 2 ohms.
 
Just to clarify, here are examples of "series" and "parallel" wiring.

Series wiring raises the impedance of the speaker circuit, and this is an easier load for an amplifier to drive. Total sound output will generally be not as loud with this type of load. (Less output wattage)

series_wiring.png


Parallel wiring lowers the impedance of the circuit, this is a more difficult load for the amplifier to drive, some amplifiers are OK driving lower impedance, but there is always a limit. Sound output will generally be louder with this type of load. (more output wattage)

spkr_p.gif



Speakers are resistance loads, like a resistor. You could actually put a resistor in place of a speaker, problem is, it wouldn't make any sound, just heat.

Generally you don't want to test the load handling of an amplifier by just dropping the resistance of the speaker load until it blows, that is unless you have an infinite supply of amplifiers. :)

Hope this helps. Sorry the two examples are of not the same impedance speakers, but if the second example had 4 ohm speakers, the load to the amplifier would be 2 ohms.

I hope you posted this cause of references to daisy chaining and being parallel. :p
 
I hope you posted this cause of references to daisy chaining and being parallel. :p


Haha, I did!

I always thought of "daisy chain" as being a series connection. But then I thought, "well that's a bullshit term anyway, lets just use the proper nomenclature"
 
Haha, I did!

I always thought of "daisy chain" as being a series connection. But then I thought, "well that's a bullshit term anyway, lets just use the proper nomenclature"

Glad you posted the images. I always thought of daisy chaining as parallel...

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