Multiple speakers thru a boombox?

j0ckinjz

Member
2010-05-10 5:25 am
Ok, so I am building a bar out of an old 53" projection TV that I could fix :(
I decided to keep the speakers in it and use them for music. But I suck at wiring speakers so I need some help.

I have an old "boombox" its a sony zw755. It's built in amp is rated at 3.2 ohms. It has 2 channels.

Here are the list of speakers I have:
(2) 8ohm speakers that came with the tv (mitsubishi tv, no clue what brand speakers)
(2+) 8ohm Pioneer speakers (a11ec80-02f)
(2) 4/8 ohm Audiovox (SL-50) with tweeter and midrange.

As far as I can tell as long as my amp has a lower ohm rating than the speakers, I wont blow anything...?

But what If I wanted to hook up the Pioneer speakers with the audiovox speakers. Could I hook them up in parallel or series or something? Or is my amp not good enough.

p.s. sorry for being such a noob.
 

wakibaki

Banned
2008-01-08 11:51 pm
Hmm. Where to start?

Amps are usually rated for power (Watts) into an impedance (Ohms), e.g 10 Watts into 4 Ohms. An impedance is like a resistance but for AC circuits. This is because AC can pass through and be affected by a capacitance or a coil (inductance).

If you put too much power into a speaker you will destroy it, i.e 10W into a speaker rated for 1W.

If you connect too small an impedance to an amplifier you run the risk of blowing the amplifier up, although some have built in protection to prevent blow-ups.

3.2 Ohms is a odd number. Speakers are usually 4 or 8 ohms nominal, so I don't trust it.

2 * 8 Ohm speakers in series is 16 ohms. Pretty safe. 3 in series would be 24 Ohms.

2 * 8 Ohm speakers in parallel is 4 Ohms (1/[1/R1]+[1/R2]), in this case (1/[1/8]+[1/8])= (1/[2/8]]=(1/[1/4])=4. I used R for resistance since the rule is true for resistances and impedances, the symbol for impedance is Z.

4 Ohms is the minimum rating for most amps, although some are 8, and some go down as low as 2 or even less.

So there isn't really a straightforward answer to the question, not without knowing the power ratings of the amp (into what impedance) and the speakers. That said, most speakers except very small ones will tolerate the output of a boombox amp, except a very powerful one.

w
 
@Wakibaki ...maybe it's an LA4597 , rated at about 5W on a 3,2 Ohm speaker... kept under 1 W (low volume) does not reach its ugly distortion .

I would avoid any serial or parallel connection unless someone's sure of what's behind the *black boxes* ,amps and speakers .
Looking at an amplifier's power supply ,you'll get an idea of it's power rating.
 

j0ckinjz

Member
2010-05-10 5:25 am
this is all I could find from the spec sheet.
Power Handling Capacity: With 3.2-ohm loads, both channels
driven from 150-6300Hz; rated 1.6 W per channel minimum RMS
power, with no more than 10% total harmonic distortion in AC
operation.

the audiovox speakers are 300w
the pioneer speakers are 20w
 
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