Speaker question

Hi everyone,

I am building a very odd project, and to make a long story short, this is the next phase of it. I took a 27" stereo television out of its cabinet and it has two 2.5 watt/8 ohm speakers attached to it from the circuit board. I would like to add two additional speakers to this set up, but am not sure how to do it or if its possible. I guess I should bore you with some of the other details so you can get a full understanding of what I’m trying to do.
I purchased an old sit-down driving arcade cabinet and I am converting it to a dedicated xbox driving game. I installed the monitor from the old tv cabinet into the arcade cabinet yesterday, now I want to move on to the speaker portion. The seat for the driving cabinet has two speakers built in to the headrest and the cabinet front has two speakers built in to itself also. (total of four speakers) The problem, as I said before, is that the tv that I installed only has two speakers coming off of the circuit board and I want to wire up the four that I have on the arcade cabinet. How can I do this? I don’t know what restrictions I am up against as far as ohms and wattage. ( I don’t know anything about ohms or wattage) I thought that I could just snip the old speakers off of the tv circuit board and wire a set of two speakers for the left side and a set of two speakers for the right side and be done with it. I asked around on one of the web sites that I visit and it doesn’t sound like thats possible without problems. Can you give me some guidance please? I can also send some pictures of the project if my description didn’t make sense.
Rich
richblacksmith@adelphia.net

You’ll need to know how many ohms the output stage of the aracade audio amp is… Is it 8 ohm (usually so) or 4 ohm. The reason: If you attach 4 ohm speakers to an 8 ohm outlet you’ll probably blow the speaker voice coils at full volume. If my electronics knowledge serves me right, a 4 ohm speaker’s highest power input is halved when attached to a 8 ohm output (eg: 20 watts max. power becomes 10 watts…). Also, you’ll need to check if the speakers are magnetically shielded so as not to magnetically gauze and wreck your picture tube. If they came from a tv, then I’d say they probably are…but check (magnets will have a thick overshield).
Next, make sure that you put neg to neg and pos to pos…simple, but sometimes overlooked by people in a hurry.
Last (and tell me to nick off if your electronics knowledge is good in this area)…make goddam sure you don’t touch the neck connectors of that tube, even when it is off. Tubes act like huge capacitors and will retain a charge long after there is no current…they can kill. Also, when powering a tube up on first switching on the amperage (strength of the electricity) is very high…be careful. If the tube falls on its neck due to mishandling you could have an implosion/explosion as powerful as a grenade…PLEASE be careful. Get a techie person to help you on this project.

Stroppy, thanks for the reply. I understand your concerns about the monitor. Thanks. It is already installed in the cabinet, so I think I’m ok there. Regarding the speaker issue, if the original speakers are 2.5 watt / 8 ohms each, can I add two more 2.5 watt / 8 ohm speakers to the set-up? Also, if I keep them 8 ohm, since that was what came with the tv, can I install bigger watt speakers or does it have to stay the same?

Okay…sorry- I was terrified you would fry yourself. Saw it happen to an ex friend of mine once…not a pretty sight!
You can add more speakers of the same ohm rating but each time you daisy chain speakers on, or up the pwoer required to drive the speakers you risk 2 things:
1./ Overloading the audio amp in the tv.
2./ Reducing the overall power available to all speakers, as increased
attachments cause increased resistance. (God, you’re taxing my
electrical knowledge now!)
3./ If output power is reduced, then you could have that strange effect
known to all hifi nuts as speaker clipping due to not pushing enough
power through speakers designed for higher outputs…eg:
If you put 100 watt speakers on a 15 watt amp, then you need to
drive that amp at high volume to get decent sound, causing the
effect known as “clipping”. This is death to speaker voice coils.

Look at this link:
http://www.crutchfieldadvisor.com/ISEO-rgbtcspd/learningcenter/home/speakers_faq.html

Anyways…hoped this helped.
knowledge now!)

Stroppy, I guess I see what you are saying. Now I’m in sort of a delemma. I’d sure like to have four speakers, but don’t want to damage anything or affect the performance of the speakers. Is there any way that I can take the left and right speaker wires off of the tv and run them through a separate amp and then out to 4 speakers??? If so, I need very basic directions. I suppose the easiest way would have been if the tv had audio output jacks, but it doesn’t. I’m wondering if the wires coming from the speakers could get rca (?) plugs soldered to the ends and plugged into a stereo amp?

Sorry for the delay in answering you question…sleep intervened (remember, I’m half way around the planet from you).

Do not connect leads intended for direct connection to speakers to an RCA jack and
then reconnect to another amp. That path will lead you to amp burnout and big repair bucks.

Go to your local Radio Shack/Tandy store and tell the guys what you’re trying to do. There is a way of placing a resistor in line with the speaker cable to reduce its output such that you can connect it to another amp via RCA. They may be able to sell you a kit to do just that and it would be rather simple to solder and wire up. If you were in Australia, where I live, I would direct you to this site:
www.jaycar.com.au
Where you would find advice plus the product you need.
Good luck