Surround Sound Front Speakers

[Tecnic]

I have a set of Panasonic SB-AK78 front surround speakers. These speakers are 4 way, 4 speaker units having a super woofer, woofer, tweeter and super tweeter. All are 6 Ohm. The High and Mid are rated at 60W. The Low rated at 200W. They are also called Tri-Wired speakers. By this instead of one positive and one negative lead they have three sets of wires, One set each for High, Mid, and Low. The label on the back states only use with Panasonic design units such as the SC-DK3 Stereo System. Other wise could cause fire or malfunction. (Didn't know if this was manufacturer hype or fact). The SC-DC3 and like designed units have 12 front speaker connections (6 for the right speaker and 6 for the left speaker). Anyway, my question is can something like these speakers be wired to support hook up to a receiver with just one positive and one negative connection for each speaker. I.E. How do you defeat or remove the tri-wire system and use these speakers on a standard run of the mill receiver. I do not not know that internals look like because I have not yet figured out how to open them up. that would be my next question. If they can be modified, how do you open them up? Any help or advise is appreciated.

 

[j_garcia]

These actually look like they were part of some kind of boom box type shelf system. I would say yes, they can easily be wired together and any receiver should be able to handle them, but I'd honestly look for other speakers.

 

[TLS Guy]

I have a set of Panasonic SB-AK78 front surround speakers. These speakers are 4 way, 4 speaker units having a super woofer, woofer, tweeter and super tweeter. All are 6 Ohm. The High and Mid are rated at 60W. The Low rated at 200W. They are also called Tri-Wired speakers. By this instead of one positive and one negative lead they have three sets of wires, One set each for High, Mid, and Low. The label on the back states only use with Panasonic design units such as the SC-DK3 Stereo System. Other wise could cause fire or malfunction. (Didn't know if this was manufacturer hype or fact). The SC-DC3 and like designed units have 12 front speaker connections (6 for the right speaker and 6 for the left speaker). Anyway, my question is can something like these speakers be wired to support hook up to a receiver with just one positive and one negative connection for each speaker. I.E. How do you defeat or remove the tri-wire system and use these speakers on a standard run of the mill receiver. I do not not know that internals look like because I have not yet figured out how to open them up. that would be my next question. If they can be modified, how do you open them up? Any help or advise is appreciated.

Panasonic are correct you can not use those speakers with a different unit.

Your Head unit, which I suppose has bitten the dust, triamped the front speakers. That is to say there was an amplifier connected directly to each speaker. The crossovers were active ahead of the amplifiers.

A standard receiver has just two amps for the front left and right and assumes a speaker with a passive crossover after the amp in the speakers.

So if you try and connect those speakers to another unit, they will breath fire.

The only way they could be modified is to measure all the drivers electro/acoustic parameters and design and build a passive crossover. It likely might not be possible as if the woofer should be more sensitive than the other speakers, a passive solution is not possible.

The bottom line is that those speakers are absolutely not worth the effort involved and need a trip to the recycling center ASAP.

 

[TLS Guy]

These actually look like they were part of some kind of boom box type shelf system. I would say yes, they can easily be wired together and any receiver should be able to handle them, but I'd honestly look for other speakers.

Sorry you got that one wrong. Believe it or not those speakers are triamped from the head unit. The speakers contain no crossovers and who knows what the impedances are. I suspect that system was designed by their car division where such practice is common.

Also if the OP does what you suggest, his receiver will be damaged by seeing a very low impedance.

 

[j_garcia]

Even without a passive x-over, I think they could be wired up and still work because I highly doubt the drivers are going to draw much real current. After looking at them, and as I mentioned before, I'd definitely say not worth the time. There are plenty of "basic" speakers out there with no crossover and they work. These either came with an all-in-one turntable/cassette/FM juke box or a boom box with detachable speakers on the cheap.

 

[TLS Guy]

Even without a passive x-over, I think they could be wired up and still work because I highly doubt the drivers are going to draw much real current. After looking at them, and as I mentioned before, I'd definitely say not worth the time. There are plenty of "basic" speakers out there with no crossover and they work. These either came with an all-in-one turntable/cassette/FM juke box or a boom box with detachable speakers on the cheap.

If you do as you say, all the drivers will see a full range signal and the tweeters will explode instantly.

Here is what those speakers were part of.

It seems each driver was around six ohms, so if they were all connected together it would be a 2 ohm load.

Each speaker has a woofer, mid, ring dome tweeter and a piezo tweeter, this latter would not need a crossover, but might have an L-pad.

Anyhow my advice still stands for a trip to the recycling center.

 

[j_garcia]

Well, the tweeters either already have a cap on them or the signal was filtered in the unit itself then, because I would have expected the same thing to happen.

I pulled an old PC speaker out and ran a few hundred watts (big amp cranked all the way) of music signal through it to see if it would expire. No crossover, no mercy. To my amazement, it did not. It was more or less clean signal also though.

 

[slipperybidness]

It seems each driver was around six ohms, so if they were all connected together it would be a 2 ohm load.

A 2ohm load, assuming wired in parallel. Various combinations of parallel and series could possibly get you where you needed to be.

But, with the time and effort and the fact that these are probably crappy-sounding anyway, I agree with the recycling.

 

[TLS Guy]

Well, the tweeters either already have a cap on them or the signal was filtered in the unit itself then, because I would have expected the same thing to happen.

I pulled an old PC speaker out and ran a few hundred watts of music signal through it to see if it would expire. No crossover, no mercy. To my amazement, it did not. It was more or less clean signal also though.

Sure, but the high pass filter is ahead of the amplifier. In biamped and triamped systems the amps are directly connected to the speakers voice coils, nothing in between!

 

[TLS Guy]

A 2ohm load, assuming wired in parallel. Various combinations of parallel and series could possibly get you where you needed to be.

But, with the time and effort and the fact that these are probably crappy-sounding anyway, I agree with the recycling.

You would still need a crossover. If the drivers are truly 6 ohm then if you made a three way passive crossover the speakers would be nominally six ohm.

You absolutely can not wire those speakers any way you can think of without a crossover. All speakers including the ring dome tweeter will see a full range signal and you can not do that.

You guys are just encouraging the OP to ruin his receiver.

There is no practical way he can use those speakers without risking severe damage as it states in the manual with a pertinent graphic warning.

 

[GranteedEV]

MY advice to OP is to take a screwdriver to the drivers, and show us what is inside the box.

I find it hard to believe these are ACTIVE tri-amped loudspeakers.

 

[slipperybidness]

You would still need a crossover. If the drivers are truly 6 ohm then if you made a three way passive crossover the speakers would be nominally six ohm.

You absolutely can not wire those speakers any way you can think of without a crossover. All speakers including the ring dome tweeter will see a full range signal and you can not do that.

You guys are just encouraging the OP to ruin his receiver.

There is no practical way he can use those speakers without risking severe damage as it states in the manual with a pertinent graphic warning.

Yeah you need a crossover. I was just pointing out that saying it would be a 2ohm load made some assumptions.

I agree, the OP has a bad idea. He can take your advice or figure it out the hard way.

 

[TLS Guy]

Yeah you need a crossover. I was just pointing out that saying it would be a 2ohm load made some assumptions.

I agree, the OP has a bad idea. He can take your advice or figure it out the hard way.

I was not making any assumptions.

Lets take three identical 6 ohm speakers. There are only four possibilities.

1). All in parallel=2 oms.

2). All in series=18 ohms.

Note these are the only two solutions that allow for equal power distribution between the drivers.

3). 2 drivers in parallel with the two parallel drivers in series with the third driver. 3+6 ohms=9 ohms. The two series drivers will each take one sixth of the power with the single series driver taking 2/3 of the power.

4). Two drivers in series with the third driver in parallel with the two series drivers=1/12 + 1/6=3/12, now resolve the reciprocal and you get 4 ohms. However the series drivers take 25% of the power each and the third driver in parallel with the series drivers takes half the power.

Now we take pride on this forum on providing accurate information.

Please do your math before posting misleading information.

 

[slipperybidness]

It seems each driver was around six ohms, so if they were all connected together it would be a 2 ohm load.

Uuuuummmmmm. Hhhhhmmmmm.

I'm not questioning your math, it is correct. I'm saying you made an assumption as to how he planned to connect these.

If they were all connected together in PARALLEL you get a 2ohm load. Seems that you made an ASSUMPTION that he would connect them in parallel when you made the above statement. Am I wrong??? Not likely.

Your math (my math) is correct. I'm just saying that your original quote was not necessarily true (in all situations).

Now we take pride on this forum on providing accurate information.

Fact is, parallel would make the most sense to someone like you or me so you defaulted to that scenario. But, someone like you or me would realize that this is probably not the best idea long before we got to the question of how to wire it.

 

[zieglj01]

The label on the back states only use with Panasonic design units such as the SC-DK3 Stereo System. Other wise could cause fire or malfunction. (Didn't know if this was manufacturer hype or fact).
If they can be modified, how do you open them up? Any help or advise is appreciated.

It is not hype from Panasonic, and the speakers are not worth it.

 

[TLS Guy]

MY advice to OP is to take a screwdriver to the drivers, and show us what is inside the box.

I find it hard to believe these are ACTIVE tri-amped loudspeakers.

Well then read the manual! They clearly are and so state, the power of the three amps are clearly stated and the crossover points in the manual. Do you think Panasonic are just going to make this up?

Obviously, as I have long suspected, it is cheaper to do it this way then furnish passive crossovers.

 

[lsiberian]

MY advice to OP is to take a screwdriver to the drivers, and show us what is inside the box.

I find it hard to believe these are ACTIVE tri-amped loudspeakers.

I couldn't believe it either, but the manual made it pretty obvious. With chip amps I think this will become more common.