Hi,

Quick question. I have a Panasonic Amp - average one, 45W RMS (6ohm)
per channel.

I want to connect 4 speakers to it ..... the four - 2 6 ohm speakers
have 170W maximum input power, and 2 4 ohm with 70W max. input power.
Theyre all the same style, just designed for a home theater - slightly
different application here!

Basically, the four are going to be playing music very softly - people
are coming over and so just to have some nice soothing background
music, that wont hinder people's conversations.

Is this safe for the amp? I had thought it would - especially
considering the very low volume needed (and the fact that no one can
accidentally turn the volume up).

Appreciate any help - thanks,
Andrew

"andrew_h" wrote ...

Quick question. I have a Panasonic Amp - average one, 45W RMS (6ohm)
per channel.

I want to connect 4 speakers to it ..... the four - 2 6 ohm speakers
have 170W maximum input power, and 2 4 ohm with 70W max. input power.
Theyre all the same style, just designed for a home theater - slightly
different application here!

Basically, the four are going to be playing music very softly - people
are coming over and so just to have some nice soothing background
music, that wont hinder people's conversations.

Is this safe for the amp? I had thought it would - especially
considering the very low volume needed (and the fact that no one can
accidentally turn the volume up).

The "power ratings" of the speakers are of no consequence
for your question (or any other, for that matter).

The basic question is what is the LOWEST impedance
which your amplifier is rated for? You say that it is rated
for 45W @ 6-ohms. Is 6-ohms the minimum impedance?

Connecting a lower impedance to the amplifier than its
ratings could stress it to the point of burning out several
critical (and expensive) parts. One could argue that if you
are running low "background music" levels, you could
possibly get away with it. But that reminds me of the
people who keep their goldfish in a blender plugged into
the mains power. One slip away from disaster.

If you are running low-level background music, you don't
really need the full power output of the amplifier. So the
safest way would be to connect one of the 6-ohm speakers
*in series* with one of the 4-ohm on each channel of the
amplifier. This will present a 10-ohm load on each side
of the amp. You won't get the full 45 watts, but in your
application, it doesn't matter and everyone will be cool.

Richard,

Thanks heaps for your reply. Checking the book, it says:

"80 Hz, both channels driven. (Low channel) 115W per channel (6ohm)"
"1kHz, both channels driven. (High channel) 45W per channel (6ohm)".
Total Bi-Amp Power 160W per channel......................

When I did a quick test last night, I actually connected two of the
speakers both into one amp output, and the other two to the other
two(in parallel). So in essence, say the first two speakers - one 6ohm
and one 4ohm....therefore connecting both to the one output would
reduce the impedance to 5ohm - is this correct?

And looking at what I have just read, I shouldnt let the impedance drop
under 6 should I?

So this is why you say to connect two in series to one output, and the
other two to the other?

Thanks - sorry if the question sounds newbie, I am learning more and
more about speaker and amp setups!


Cheers,
Andrew



Richard Crowley wrote:
"andrew_h" wrote ...

Quick question. I have a Panasonic Amp - average one, 45W RMS (6ohm)
per channel.

I want to connect 4 speakers to it ..... the four - 2 6 ohm speakers
have 170W maximum input power, and 2 4 ohm with 70W max. input power.
Theyre all the same style, just designed for a home theater - slightly
different application here!

Basically, the four are going to be playing music very softly - people
are coming over and so just to have some nice soothing background
music, that wont hinder people's conversations.

Is this safe for the amp? I had thought it would - especially
considering the very low volume needed (and the fact that no one can
accidentally turn the volume up).

The "power ratings" of the speakers are of no consequence
for your question (or any other, for that matter).

The basic question is what is the LOWEST impedance
which your amplifier is rated for? You say that it is rated
for 45W @ 6-ohms. Is 6-ohms the minimum impedance?

Connecting a lower impedance to the amplifier than its
ratings could stress it to the point of burning out several
critical (and expensive) parts. One could argue that if you
are running low "background music" levels, you could
possibly get away with it. But that reminds me of the
people who keep their goldfish in a blender plugged into
the mains power. One slip away from disaster.

If you are running low-level background music, you don't
really need the full power output of the amplifier. So the
safest way would be to connect one of the 6-ohm speakers
*in series* with one of the 4-ohm on each channel of the
amplifier. This will present a 10-ohm load on each side
of the amp. You won't get the full 45 watts, but in your
application, it doesn't matter and everyone will be cool.

andrew_h wrote:
Richard,

Thanks heaps for your reply. Checking the book, it says:

"80 Hz, both channels driven. (Low channel) 115W per channel (6ohm)"
"1kHz, both channels driven. (High channel) 45W per channel (6ohm)".
Total Bi-Amp Power 160W per channel......................

When I did a quick test last night, I actually connected two of the
speakers both into one amp output, and the other two to the other
two(in parallel). So in essence, say the first two speakers - one 6ohm
and one 4ohm....therefore connecting both to the one output would
reduce the impedance to 5ohm - is this correct?

No. A 4 ohm speaker in parallel with a 6 ohm speaker is 2.4 ohms.

And looking at what I have just read, I shouldnt let the impedance drop
under 6 should I?

Probably not.

So this is why you say to connect two in series to one output, and the
other two to the other?

Yes, that will result in a 10 ohm load.

// Walt
//

"andrew_h" wrote ...
Richard,

Thanks heaps for your reply. Checking the book, it says:

"80 Hz, both channels driven. (Low channel) 115W per channel (6ohm)"
"1kHz, both channels driven. (High channel) 45W per channel (6ohm)".
Total Bi-Amp Power 160W per channel......................

This is some sort of bi-amp setup? Does that mean that there are
NO full-range outputs? (If you have only "Low channel" and
"High chanel" outputs?) That seems like a problem with what
you are attempting to do.

When I did a quick test last night, I actually connected two of the
speakers both into one amp output, and the other two to the other
two(in parallel). So in essence, say the first two speakers - one 6ohm
and one 4ohm....therefore connecting both to the one output would
reduce the impedance to 5ohm - is this correct?

As "Walt" has already calculated for us, the impedance is
more like 2.4 ohms.

And looking at what I have just read, I shouldnt let the
impedance drop under 6 should I?

It becomes more problematic the lower it goes. I would
definitely NOT feel comfortable with a 2.4 ohm load on
such an amplifier. Too close to the edge for my tastes.

So this is why you say to connect two in series to one
output, and the other two to the other?

Definitely. And make sure to get one 6-ohm and one 4-ohm
in series on each side to keep the load balanced. NOT
both 6-ohm speakers on one side and both 4-ohm speakers
on the other side.

Forgive my newbieness....
Bl W R Bla - Bl= blue, W= white, R= red, Bla=black
[x][x][o][o]
[x][x][o][o]
Speaker outputs

The first two outputs (x's) are for 'high-channel' output (6 ohm), and
the other two (o's) are for 'low-channel' output (6 ohm). Looking at
the manual - for each supplied panasonic speaker, one speaker lead
connects into box X's (is split at the end into two), and the other
into both O's (from the one speaker). Then with the other speaker, the
same thing into the other two lots.

Is this a problem ? Could I just use the 'high-channel' outputs, as the
music that will be playing (i.e. flute music etc), will not have much
bass and low frequencies??

"andrew_h" wrote ...
Forgive my newbieness....
Bl W R Bla - Bl= blue, W= white, R= red, Bla=black
[x][x][o][o]
[x][x][o][o]
Speaker outputs

The first two outputs (x's) are for 'high-channel' output (6 ohm), and
the other two (o's) are for 'low-channel' output (6 ohm). Looking at
the manual - for each supplied panasonic speaker, one speaker lead
connects into box X's (is split at the end into two), and the other
into both O's (from the one speaker). Then with the other speaker, the
same thing into the other two lots.

Is this a problem ? Could I just use the 'high-channel' outputs, as
the
music that will be playing (i.e. flute music etc), will not have much
bass and low frequencies??

I'm completely baffled what this even is? Can you describe
it more completely? Does it have a name, model number?
Where did it come from? What was it used for before you
got it? It does NOT sound anything like a conventional
amplifier, at least to me.

haha...

Panasonic SA-AK44 stereo.

Sorry..

Panasonic SA-AK44 5 cd/radio stereo system.

On 22 Feb 2006 23:55:47 -0800, "andrew_h"
wrote:

haha...

Panasonic SA-AK44 stereo.

It's a boom box! From the manual
(http://www.usersmanualguide.com/pana...system/sa-ak44
there is a caution: "Use only the supplied speakers........... Using
other speakers can damage the unit......."

I wouldn't doubt it.

Kal

"andrew_h" wrote ...
Panasonic SA-AK44 5 cd/radio stereo system.

I have no idea what "high-channel" and "low-channel"
mean in this context. Anybody else got a clue?

From the photo in a listing on ebay in GB, it appears
to be a plastic "boom box" with two "semi-detached"
speakers. Is this what you've got?

What happens if you just connect one of your speakers
to each of the outputs? You have four outputs and four
speakers, right?

Richard Crowley wrote:
"andrew_h" wrote ...

Panasonic SA-AK44 5 cd/radio stereo system.

I have no idea what "high-channel" and "low-channel"
mean in this context. Anybody else got a clue?

Might be bi-amped, but I doubt it - never heard of a bi-amped boom box.
Perhaps some sort of equalized output to compensate for cheesy speakers?

From the photo in a listing on ebay in GB, it appears to be a plastic
"boom box" with two "semi-detached" speakers. Is this what you've got?

What happens if you just connect one of your speakers to each of the
outputs? You have four outputs and four speakers, right?

That sounds like a pretty good place to start. I doubt it'll break
anything, but there's no way to know for sure given the available
information.

///Walt

Richard Crowley wrote:
"andrew_h" wrote ...

Panasonic SA-AK44 5 cd/radio stereo system.


I have no idea what "high-channel" and "low-channel"
mean in this context. Anybody else got a clue?

From the photo in a listing on ebay in GB, it appears to be a plastic
"boom box" with two "semi-detached" speakers. Is this what you've got?

What happens if you just connect one of your speakers to each of the
outputs? You have four outputs and four speakers, right?
The panasonic Sc-Ak 44 (if my memory is ok) is a bi-wired dual amp
mini-stereo. Each speaker include a Super-Woofer???, 1 Tweeter and 1
mid-bass driver. The High-Channel go to the tweeter and mid-bass and the
low-Channel go to the Super-Woofer. So correct me if I am wrong but if
you want to connect a different speaker to the SC-AK 44, the low channel
will go to your woofer and the High-Channel will go to the Mid/High
frequency driver (you must use a x-over if you do not want to blow your
tweeter)

Hope this help.

"andrew_h" wrote in message
oups.com

Yeh - it is more than just a 'boom box'. From memory I
paid just under $400 Aus.

Actually the speakers are very good - J.Major was spot on
- 'super-woofer, tweeter, and mid' drivers on each, and
they ARE bi-wired. The amp has two high-channel outputs,
and two low-channel outputs.

Actually, they are bi-amped.

Basically, I am finding it a bit hard to 'join' the high
and low channel outputs and then run them to the
speakers.

Good way to blow power amps up.

The four speakers I'm wanting to use are
Panasonic (long thin ones), the sound is very good. As
people have suggested, I have wired 2 in series (as the L
channel), and the other 2 in series (as R). I tried
making a Y connector out out speaker cable ... the top
left of the Y going to the +ve of the high-channel, the
top right of the Y going into the +ve of the low-channel,
and then the bottom of the Y connecting to the +ve of the
first speaker. Same with the -ve's of one side. This
doesnt seem to work though - I cant see why?!

This is a system with components that are designed to work together and no
other way. Changing out significantly different components would take some
serious engineering.

On 23 Feb 2006 14:45:27 -0800, "andrew_h"
wrote:

Yeh - it is more than just a 'boom box'. From memory I paid just under
$400 Aus.

Expensive boom box.

Actually the speakers are very good - J.Major was spot on -
'super-woofer, tweeter, and mid' drivers on each, and they ARE
bi-wired. The amp has two high-channel outputs, and two low-channel
outputs.

Doesn't make it very good, just excessively complex.

Basically, I am finding it a bit hard to 'join' the high and low
channel outputs and then run them to the speakers. The four speakers
I'm wanting to use are Panasonic (long thin ones), the sound is very
good. As people have suggested, I have wired 2 in series (as the L
channel), and the other 2 in series (as R). I tried making a Y
connector out out speaker cable ... the top left of the Y going to the
+ve of the high-channel, the top right of the Y going into the +ve of
the low-channel, and then the bottom of the Y connecting to the +ve of
the first speaker. Same with the -ve's of one side. This doesnt seem to
work though - I cant see why?!

Anyone know how I could join these?

Joining the outputs of two amps is a good way to blow the amps.
Only if you are willing to chance destroying the unit in your attempt
should you bother.

Kal

I am not 'changing out components' apart from changing the speakers!!!

If the highs come from the high-channel, and the lows from the
low-channel, it must be possible to join the two outputs so that all
the frequencies run down the one speaker cable to the speaker, which
could handle both low and high. The idea of the "Y" was so that the +ve
of the high and the +ve of the low both go to the +ve of the speaker
..... not into themselves. Therefore as I see it, I would think the
frequencies would just both travel down the one speaker wire to the
speaker. Correct???

I meant if the low bass frequencies from the low, and the mids up come
from the high!

I tuned in late, but are you talking about tying together two speaker
outputs to a single speaker? Don't do it. A speaker output is a high-power
device. Each speaker output is trying to control the voltage on the
speaker. If you tie 2 outputs together, and at some moment one of the
outputs is trying to put -1 volt on the speaker at the same time the other
one is trying to put +3 volts on the speaker (and remember, we're talking
about instants in the progress of a sound wave), then the outputs will burn
each other out.

Unlike sounds themselves, electronic signals representing sounds can't be
added together by just feeding them to the same place.

I'm not sure what kind of Y connector you have in mind, but it is not
possible (with wires) to connect A to C and connect B to C without also
connecting A to B. (Assuming you want something that will pass an audio
signal. It can be done with diodes for DC only.)

"andrew_h" wrote in message
oups.com...
I am not 'changing out components' apart from changing the speakers!!!

If the highs come from the high-channel, and the lows from the
low-channel, it must be possible to join the two outputs so that all
the frequencies run down the one speaker cable to the speaker, which
could handle both low and high. The idea of the "Y" was so that the +ve
of the high and the +ve of the low both go to the +ve of the speaker
.... not into themselves. Therefore as I see it, I would think the
frequencies would just both travel down the one speaker wire to the
speaker. Correct???

"andrew_h" wrote in message
oups.com

Yeh I was just thinking about using diodes.

Diodes are incredibly nonlinear and muck up the sound when put into speaker
lines.

Look buddy, you've been told by three different people that this is a bad
idea. Kal in particular has a long track record of accurate posts around
here.

Maybe you should step back, take a deep breath and stop wasting good
people's time with mission impossible?

After all you can get a good 100 wpc stereo receiver for like $100 if you
want to start using regular speakers.

I understand exactly what you are saying.

The main, 100% reason for posting and pushing to try and find a
solution was because I was having the dinner this weekend and so wanted
to try and fix something up so it'd work well - even a make-shift
solution just for this weekend.

The speakers in series connect fine to the high-channel output ...
again this sounds fine, especially for the music I plan to play, so I
think my only option will be to forget about the low-channel output ...
and have no bass at all.

Contrary to what people say about the unit being an expensive "boom
box", it actually sounds very good - I understand the market they are
aiming for with the product, namely trying to cover both amatuer
listeners (who just want sound from cds etc) and also to edge into more
serious music listeners. Personally I think the bi-amp outputs is -
maybe marketing hype - but to appeal to that more serious group. But it
is by no means a crappy unit. To the average 'music listener', it
sounds great.

"andrew_h" wrote in message
ups.com

The main, 100% reason for posting and pushing to try and
find a solution was because I was having the dinner this
weekend and so wanted to try and fix something up so it'd
work well - even a make-shift solution just for this
weekend.

The problem is that in its way this may be a sophisticated unit. One problem
with sophistication is that it can tend to make things good only for one
thing - the exact job they are made to perform.

The speakers in series connect fine to the high-channel
output ... again this sounds fine, especially for the
music I plan to play, so I think my only option will be
to forget about the low-channel output ... and have no
bass at all.

Are the bass speakers broken or are you talking about the fact that mini
systems tend to be light on bass?

Contrary to what people say about the unit being an
expensive "boom box", it actually sounds very good - I
understand the market they are aiming for with the
product, namely trying to cover both amatuer listeners
(who just want sound from cds etc) and also to edge into
more serious music listeners. Personally I think the
bi-amp outputs is - maybe marketing hype - but to appeal
to that more serious group. But it is by no means a
crappy unit. To the average 'music listener', it sounds
great.

FWIW biamping is also used on a lot of *professional* studio monitors. It
can solve a number of inherent problems with speakers and amplfiers if done
right.

Thing is, the more you optimize somehting to do a certain job, the less
likely it is to be general-purpose.

"andrew_h" wrote ...
I am not 'changing out components' apart from changing the speakers!!!

If the highs come from the high-channel, and the lows from the
low-channel, it must be possible to join the two outputs so that all
the frequencies run down the one speaker cable to the speaker, which
could handle both low and high. The idea of the "Y" was so that the
+ve
of the high and the +ve of the low both go to the +ve of the speaker
.... not into themselves. Therefore as I see it, I would think the
frequencies would just both travel down the one speaker wire to the
speaker. Correct???

NO! You seem to have a "bi-amped" system where the audio
is split low/high internally and then amplified through two
different amplifiers for each channel (total four amplifiers).
There is no practical and effective way to "re-combine" these
low/high signals back into a speaker-level, full-range signal.
Your equipment is NOT suitable for what you are asking to do.

If you had a more conventional boom-box (one with two wires
to each speaker), you COULD do what you are seeking. But
NOT with the equipment you have.

"Richard Crowley" wrote in message



NO! You seem to have a "bi-amped" system where the audio
is split low/high internally and then amplified through
two different amplifiers for each channel (total four
amplifiers). There is no practical and effective way to
"re-combine" these low/high signals back into a
speaker-level, full-range signal. Your equipment is NOT
suitable for what you are asking to do.

Agreed.

If you had a more conventional boom-box (one with two
wires to each speaker), you COULD do what you are
seeking. But NOT with the equipment you have.

In this day of ca. $1.98 high-performance DSP chips it is becoming more and
more common for the electronics in all-in-one systems to be carefully tuned
to the speakers that come with them.

This means that changing out a speaker in an all-in-1 system to a *better*
one could:

(1) Not improve things

(2) Actually make things worse

"Arny Krueger" wrote ...
In this day of ca. $1.98 high-performance DSP chips it is becoming
more and more common for the electronics in all-in-one systems to be
carefully tuned to the speakers that come with them.

This means that changing out a speaker in an all-in-1 system to a
*better* one could:

(1) Not improve things
(2) Actually make things worse

Agreed. But the application is a temporary, low-level
background music source. Lighten up. :-)

"Richard Crowley" wrote in message

"Arny Krueger" wrote ...
In this day of ca. $1.98 high-performance DSP chips it
is becoming more and more common for the electronics in
all-in-one systems to be carefully tuned to the speakers
that come with them. This means that changing out a speaker in an
all-in-1
system to a *better* one could:

(1) Not improve things
(2) Actually make things worse

Agreed. But the application is a temporary, low-level
background music source. Lighten up. :-)

Hey, I'm serious about my background music - I wear earplugs in elevators to
avoid damage due to bad Muzak! ;-)

"andrew_h" wrote in message
oups.com...
Yeh I was just thinking about using diodes.

I.e. Think of my Y connector.

No. The signals to the speaker are alternating current. Diodes would
produce terrible distortion.

It's interesting to analyze what confused you here...

I think basically you were not sufficiently aware of the difference between
sound and electricity.

There is nothing wrong with putting two sources of *sound* right next to
each other and having them both put their sound into the air in almost the
same place. Speakers next to each other, outputting different sounds, do
not particularly affect each other.

But it doesn't work that way with electricity.

The electricity coming out of a speaker output is not sound. It won't be
sound until the speaker cone vibrates. It is a voltage, changing very
rapidly, that corresponds to the intended position of the speaker cone.

And if you tie two different speaker outputs together, instant-by-instant
they are not outputting the same voltage. Current will always flow from the
higher voltage into the lower one. Accordingly, current will almost always
be flowing from one of the outputs into the other one, burning out the
amplifier.

Because they are alternating voltages (swinging from maybe +10 to -10
volts), diodes don't help.

"andrew_h" wrote in message
oups.com...
I am not 'changing out components' apart from changing the speakers!!!

If the highs come from the high-channel, and the lows from the
low-channel, it must be possible to join the two outputs so that all
the frequencies run down the one speaker cable to the speaker, which
could handle both low and high.

This is a bad idea. Best case, it won't work very well since there are
separate amplifiers for the highs and the lows. Otherwise, the original
speakers wouldn't be wired like they are. Worst case, you'll blow the
amplifier circuits.

The idea of the "Y" was so that the +ve
of the high and the +ve of the low both go to the +ve of the speaker
.... not into themselves. Therefore as I see it, I would think the
frequencies would just both travel down the one speaker wire to the
speaker. Correct???

You're not an electrical engineer are you?

Jeff
--
Remove icky phrase from email address to get a valid address.

Haha no I'm not ... but I'm learning alot day by day!

"andrew_h" wrote in message
oups.com...
Haha no I'm not ... but I'm learning alot day by day!

Glad to be of service. I hope you don't mind that, as a teacher, I'm
interested in analyzing what misled you.

And I just thought of another aspect of it.

You may have thought that the + and - terminals of the speaker outputs were,
respectively, always positive and always negative. If that were so, the
output would be a (varying) dc voltage and, although it still wouldn't
actually work as proposed, your idea about how to add them would make some
sense.

In reality, the + and - on speaker connections are arbitrary. The voltage
actually swings both ways. The + and - serve to get all the speakers "in
phase," i.e., their cones all going in or out in unison, rather than some
speakers going in while others go out.

When the audio signal is a 1000-Hz tone, the output is an AC sine wave, with
the + positive and the - negative for 1/2000 of a second, then the other way
around for 1/2000 of a second, over and over. You can see how two slightly
different signals of this general type wouldn't mix by just connecting them
together.