[[email protected]]

Im trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign). I have the stereo hooked up to a 4 switch speaker
selector( radio shack 40-244) and have four set of speakers hooked up
to that - all are 8 impedance. According the the speaker selector
documentation it is also operating at 8 impedance.

Three pair of the speakers are out side and Im tired of running back
into the home to adjust the volume so I bought 2 Boston RVC90
impedance matching volume controls. One control will adjust one set of
speakers and another one will adjust the other two.

I thought I knew what I was doing until I started reading the Boston
documentation, now Im totally lost. Im assuming the one control
operating the 1 pr of speakers will be set to 1x and the other to 2x.
Is that correct

Thanks for any help
John

[Eeyore]

wrote:

Im trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign).

What do you mean by 'set to 8' (ohms) ? Modern solid state amplifiers
don't have an impedance switch like tube/valve amps used to have.

Do you mean it's rated at 8 ohms (but no less) ?


Graham

[Arny Krueger]

"Eeyore" wrote in
message
wrote:

Im trying to figure what impedance setting to use. Heres
my set up , I have a stereo thats impedance is set to
8(sorry cant make the impedance sign).

What do you mean by 'set to 8' (ohms) ? Modern solid
state amplifiers don't have an impedance switch like
tube/valve amps used to have.

Some modern SS consumer gear *does* have an impedance switch. Internally, it
drops the +/- VCC to the output stage, thus reducing output stage power
dissipation into lower impedance loads. I've seen this feature on receivers,
but there's no reason it could not appear on integrated amps or power amps
with similar marginal heat-sinking.

[[email protected]]

On Apr 26, 2:45 pm, Eeyore
wrote:
wrote:
Im trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign).

What do you mean by 'set to 8' (ohms) ? Modern solid state amplifiers
don't have an impedance switch like tube/valve amps used to have.

Do you mean it's rated at 8 ohms (but no less) ?

Graham

In trying to research the answer to by question(before posting) it was
talking about receivers set at 4,6 or 8 impedance. My is switchable
between 6 and 8.
thanks
John

[Eeyore]

wrote:

Eeyore wrote:
wrote:

Im trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign).

What do you mean by 'set to 8' (ohms) ? Modern solid state amplifiers
don't have an impedance switch like tube/valve amps used to have.

Do you mean it's rated at 8 ohms (but no less) ?


In trying to research the answer to by question(before posting) it was
talking about receivers set at 4,6 or 8 impedance. My is switchable
between 6 and 8.

So what make and model is it ? Guesswork isn't likely to be very useful to
you.

Graham

[[email protected]]

Sorry, didnt think make/model would matter. I have a Pioneer VSX-D414
receiver, manual says: 120w @ 8ohms. The speaker selector is a radio
shack 40-244rated at 8ohms as well. The Boston volume control has a
impedance selector switch to set it at 1x, 2x, 3x, 4x, 8x and 16x
ohms depending on how many speakers are on the system. The instruction
manual for the volume control is very confusing.
thanks
John


On Apr 26, 3:29 pm, Eeyore
wrote:
wrote:
Eeyore wrote:
wrote:

Im trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign).

What do you mean by 'set to 8' (ohms) ? Modern solid state amplifiers
don't have an impedance switch like tube/valve amps used to have.

Do you mean it's rated at 8 ohms (but no less) ?

In trying to research the answer to by question(before posting) it was
talking about receivers set at 4,6 or 8 impedance. My is switchable
between 6 and 8.

So what make and model is it ? Guesswork isn't likely to be very useful to
you.

Graham

[Arny Krueger]

wrote in message


Im trying to figure what impedance setting to use. Heres
my set up , I have a stereo thats impedance is set to
8(sorry cant make the impedance sign).

We write that as 8 ohms.

I have the stereo
hooked up to a 4 switch speaker selector( radio shack
40-244) and have four set of speakers hooked up to that -
all are 8 impedance. According the the speaker selector
documentation it is also operating at 8 impedance.


Three pair of the speakers are out side and Im tired of
running back into the home to adjust the volume so I
bought 2 Boston RVC90 impedance matching volume controls.

Exhaustive searching finds no information about that product.

[Eeyore]

wrote:

Eeyore wrote:
wrote:
Eeyore wrote:
wrote:

Im trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign).

What do you mean by 'set to 8' (ohms) ? Modern solid state amplifiers
don't have an impedance switch like tube/valve amps used to have.

Do you mean it's rated at 8 ohms (but no less) ?

In trying to research the answer to by question(before posting) it was
talking about receivers set at 4,6 or 8 impedance. My is switchable
between 6 and 8.

So what make and model is it ? Guesswork isn't likely to be very useful to
you.

Sorry, didnt think make/model would matter.

You expect to read your mind as to what you have ?

Yes, it's very important as certain models may have certain know flaws or
characteristics.


I have a Pioneer VSX-D414 receiver, manual says: 120w @ 8ohms.

I haven't yet Googled it but does the Pioneer info anywhere mention 4 or 6 ohm
usage ?


The speaker selector is a radio shack 40-244rated at 8ohms as well.

Part number ?


The Boston volume control

Part number ?


has a impedance selector switch to set it at 1x, 2x, 3x, 4x, 8x and 16x
ohms depending on how many speakers are on the system. The instruction
manual for the volume control is very confusing.

Do you have a link to this confusing manual ?

Graham

[Eeyore]

wrote:

Im trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign). I have the stereo hooked up to a 4 switch speaker
selector( radio shack 40-244) and have four set of speakers hooked up
to that - all are 8 impedance. According the the speaker selector
documentation it is also operating at 8 impedance.

NO !

If you'd bothered to read the manual .....
http://rsk.imageg.net/graphics/uc/rs...0244_PM_EN.pdf

You would see that this presents as low as 4 ohms to the amplifier
depending on the speakers selected. See the 'impedance chart'.

In short, your amplifier ( Pioneer VSX-D414) with an 8 ohm only rating is
not suitable for running multiple speakers. It is designed only to run a
single pair of 8 ohm loudspeakers.


Graham

[William Sommerwerck]

If you'd bothered to read the manual .....

http://rsk.imageg.net/graphics/uc/rs...0244_PM_EN.pdf

you would see that this presents as low as 4 ohms to the amplifier
depending on the speakers selected. See the 'impedance chart'.

In short, your amplifier (Pioneer VSX-D414) with an 8 ohm only rating
is not suitable for running multiple speakers. It is designed only to
run a single pair of 8 ohm loudspeakers.

The OP doesn't understand "impedance", so this explanation means nothing to
him.

I tried to find the user manual, but couldn't, and the RS page for this
product doesn't tell you anything useful. Thanks for posting this. What
surprises me is that some connections put the speakers in series, some in
parallel. Weird.

Russound used to make a speaker-selector box that kept the impedance pretty
much constant, regardless of which speakers were connected.

One could build a speaker selector -- with a very simple circuit -- such
that whether you selected one, two, three, or four speaker pairs, the
impedance would stay constant. I ought to patent it.

[Scott Dorsey]

William Sommerwerck wrote:

Russound used to make a speaker-selector box that kept the impedance pretty
much constant, regardless of which speakers were connected.

It did this by switching resistors in and out. So it would keep the
load impedance on the amp constant, but the source impedance that the
speakers saw was very different.

One could build a speaker selector -- with a very simple circuit -- such
that whether you selected one, two, three, or four speaker pairs, the
impedance would stay constant. I ought to patent it.

You can't, there is prior art, such as the Russound box.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Paul Stamler]

"William Sommerwerck" wrote in message
. ..
Russound used to make a speaker-selector box that kept the impedance
pretty
much constant, regardless of which speakers were connected.

One could build a speaker selector -- with a very simple circuit -- such
that whether you selected one, two, three, or four speaker pairs, the
impedance would stay constant. I ought to patent it.

I doubt you could; I remember such boxes from the 1950s. We had one, in
fact.

Peace,
Paul

[Richard Corfield[_3_]]

On 2008-04-27, Paul Stamler wrote:
"William Sommerwerck" wrote in message
. ..
Russound used to make a speaker-selector box that kept the impedance
pretty
much constant, regardless of which speakers were connected.

One could build a speaker selector -- with a very simple circuit -- such
that whether you selected one, two, three, or four speaker pairs, the
impedance would stay constant. I ought to patent it.

I doubt you could; I remember such boxes from the 1950s. We had one, in
fact.

If the computer industry is anything to go by you probably could patent
it. I've seen things like a fairly recent patent for something I have
a text book with sample code in dating a decade or so before the patent
application. It doesn't seem to stop them.

Anyway - The original poster could always combine speakers in parallel
and series to keep the impedance right, though as each speaker changes
impedance over frequency the effects of connecting different speakers in
series could be interesting. I've not tried it so don't know whether it
would work or not. You may get all the treble in one and all the bass in
another (extreme example)

For the original poster:

Connect two speakers in series - adds the impedances.
So 2 * 8ohm speakers gives 16ohm

Connect in parallel and, if they're the same impedance you end up
halving it. (It's 1/(1/A + 1/B) so 1/(1/8 + 1/8) = 1/1/4 = 4)

So 2 in series gives 16ohm. Parallel those pairs to get 8 again.

It sounded as if you had an impedance selector switch on the amplifier.
(You asked what to set impedance to). In that case work out what you're
going to present to it and choose that.

1 in parallel = 8ohm
2 = 4ohm (Some domestic amplifiers have a 4ohm mode)
3 = 2 2/3 ohm
4 = 2 ohm
6 = 1 1/3 ohm
8 = 1 ohm

I think choosing too low is less a problem than choosing too high if at
a problem at all. My domestic amplifier has two sets of terminals and a
"Speaker A, Speaker B, Speaker A+B, Headphones" switch on the front so can
drive two pairs of speakers or 4ohm but is perfectly happy driving one.
(Relays click inside, so it may be doing something more clever to keep
things matched. I'm trying to remember if I noted any extra transformers
when I last opened it up. I don't think so.)

I'm used to stage equipment though which is very robust. The amplifiers
we used to use were rated down to 2ohm so we could connect up to 4
speakers in parallel and we had a lovely old telephone patch panel to do
it with. We rarely connected more than 2, if we wanted to drive front
of house in mono off one channel of the mixing desk and save the other
3 we had for things like rear of house or on stage effects.

For severe Hi-Fidelity you worry about impedance matching where both
ends of the wire want the same. On stage we didn't worry so much.

- Richard

--
_/_/_/ _/_/_/ _/_/_/ Richard dot Corfield at gmail dot com
_/ _/ _/ _/
_/_/ _/ _/ Time is a one way street,
_/ _/ _/_/ _/_/_/ except in the Twilight Zone

[Arny Krueger]

"Eeyore" wrote in
message
wrote:

Eeyore wrote:
wrote:
Eeyore wrote:
wrote:

Im trying to figure what impedance setting to use.
Heres my set up , I have a stereo thats impedance is
set to 8(sorry cant make the impedance sign).

What do you mean by 'set to 8' (ohms) ? Modern solid
state amplifiers don't have an impedance switch like
tube/valve amps used to have.

Do you mean it's rated at 8 ohms (but no less) ?

In trying to research the answer to by question(before
posting) it was talking about receivers set at 4,6 or
8 impedance. My is switchable between 6 and 8.

So what make and model is it ? Guesswork isn't likely
to be very useful to you.

Sorry, didnt think make/model would matter.

You expect to read your mind as to what you have ?

Yes, it's very important as certain models may have
certain know flaws or characteristics.


I have a Pioneer VSX-D414 receiver, manual says: 120w @
8ohms.

I haven't yet Googled it but does the Pioneer info
anywhere mention 4 or 6 ohm usage ?


The speaker selector is a radio shack 40-244rated at
8ohms as well.

Part number ?

40-244

http://www.radioshack.com/sm-8-speak...i-2062682.html


The Boston volume control

Part number ?

Good question.

Probably something like this:

http://www.smarthome.com/8262w.html


Manual at:

http://www.smarthome.com/manuals/8262.pdf

has a impedance selector switch to set it at 1x, 2x, 3x,
4x, 8x and 16x ohms depending on how many speakers are
on the system. The instruction manual for the volume
control is very confusing.

Do you have a link to this confusing manual ?

[Ian Thompson-Bell]

Manual at:

http://www.smarthome.com/manuals/8262.pdf

has a impedance selector switch to set it at 1x, 2x, 3x,
4x, 8x and 16x ohms depending on how many speakers are
on the system. The instruction manual for the volume
control is very confusing.

Do you have a link to this confusing manual ?


This seems pretty straightforward so long as the speakers are of the
same nominal impedance as he amplifier output. Assume this is 8 ohms.
You need one control for ear stereo pair of speakers. If you connect two
pairs of speakers (via two controls) you set the jumpers to 2X. For 3 or
4 sets of speakers you set the jumpers on the 3 or 4 controls to 4X.

basically you have one control per stereo pair of speakers.

HTH

Cheers

Ian

[William Sommerwerck]

"Scott Dorsey" wrote in message
...
William Sommerwerck wrote:

One could build a speaker selector -- with a very simple circuit --
such that whether you selected one, two, three, or four speaker
pairs, the impedance would stay constant. I ought to patent it.

You can't, there is prior art, such as the Russound box.

But what is the prior art? My idea might be altogether new.

I tried to find Gaylord Russell -- just to say hello -- a few weeks ago, but
he's retired.

[Tim Schwartz]

wrote:
I'm trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign). I have the stereo hooked up to a 4 switch speaker
selector( radio shack 40-244) and have four set of speakers hooked up
to that - all are 8 impedance. According the the speaker selector
documentation it is also operating at 8 impedance.

Three pair of the speakers are out side and I'm tired of running back
into the home to adjust the volume so I bought 2 Boston RVC90
impedance matching volume controls. One control will adjust one set of
speakers and another one will adjust the other two.

I thought I knew what I was doing until I started reading the Boston
documentation, now I'm totally lost. I'm assuming the one control
operating the 1 pr of speakers will be set to 1x and the other to 2x.
Is that correct

Thanks for any help
John

John,

Without going into a long technical discussion, it is safer for your
amp to set it to the (numerically) lower impedance, which is the 4 ohm
setting, assuming your choices are 4 or 8 ohms. You may loose a bit of
output power, but it certainly won't hurt anything. However, you may be
asking too much of the amp, especially if you want loud volumes with all
of the speakers switched on at once.

Regards,
Tim Schwartz
Bristol Electronics

[William Sommerwerck]

The original poster could always combine speakers in parallel
and series to keep the impedance right, though as each speaker
changes impedance over frequency the effects of connecting
different speakers in series could be interesting.

To say the least! The problem is most-severe in the bass, where the
impedance rise at resonance causes the worst interaction. But it can occur
at any frequency.

Ideally, one should use the same speakers in every room.

[Scott Dorsey]

William Sommerwerck wrote:
"Scott Dorsey" wrote in message
...
William Sommerwerck wrote:

One could build a speaker selector -- with a very simple circuit --
such that whether you selected one, two, three, or four speaker
pairs, the impedance would stay constant. I ought to patent it.

You can't, there is prior art, such as the Russound box.

But what is the prior art? My idea might be altogether new.

The prior art includes series resistors, series/parallel combinations
of speakers, and multitap autotransformers.

If your idea IS new, it could be patentable.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[justmanuals]

On Apr 26, 3:08 pm, wrote:
On Apr 26, 2:45 pm, Eeyore
wrote:

wrote:
Im trying to figure what impedance setting to use. Heres my set up , I
have a stereo thats impedance is set to 8(sorry cant make the
impedance sign).

What do you mean by 'set to 8' (ohms) ? Modern solid state amplifiers
don't have an impedance switch like tube/valve amps used to have.

Do you mean it's rated at 8 ohms (but no less) ?

Graham

In trying to research the answer to by question(before posting) it was
talking about receivers set at 4,6 or 8 impedance. My is switchable
between 6 and 8.
thanks
John

This Parts & Service manual can now be purchased for $9.99 and
downloaded immediately after payment from http://www.justmanuals.com

[[email protected]]

Thanks to all your guys help everything is hooked up and working - but
I have a small problem and since this is where I started the thread I
thought Id keep it here. First heres my setup, and I'll be as
descriptive as possible.
1) I am using a Pioneer VXS D414 receiver - according to the manual
the amp has a continuous power out put of 120w @ 8 ohms. The manual
also mentions that it can be switched to 6ohms for 6ohm speakers. I
cannot find an on line version.

2) Radio Shack 40-244 Four way speaker selector (buttons A,B,C and
D)
Manual http://rsk.imageg.net/graphics/uc/rs...0244_PM_EN.pdf

3) Two Boston Acoustics Rotary Volume Controls - Model RVC90i( cant
find online manual). The controls have "Selectable impedance
magnifying: 1x 2x 4x 8x 16x. The impedance matching multipliers are
representing the multiplier used when using multiple speakers to
represent a safe impedance lever to the amp" Im using three pr of
speakers and have the selector switch set at 4x

How its hooked up: From the receiver to the input on the speaker
selector. I have one pair of speakers on button A - these wires go
straight from the selector to the speakers. 1 pr on C - these wires go
from the selector switch to the volume control to the speakers. 1 pr
speakers on D - they are wired just like C.

So here the problem and I hope its not to confusing - I leave button A
always depressed and works great. When I also depress button C
everything still works great and the volume control works like a
charm, Now if i also depress button D - this volume control, controls
the speakers on D, however it also controls the speakers on C. BUT the
control on speakers C will not control the speakers on D. Ive double
checked my wiring and nothing is crossed. Could it be something with
the speaker selector -?
Thanks
John

[Chris Hornbeck]

On Mon, 28 Apr 2008 14:15:57 -0700 (PDT), wrote:

2) Radio Shack 40-244 Four way speaker selector (buttons A,B,C and
D)

So here the problem and I hope its not to confusing - I leave button A
always depressed and works great. When I also depress button C
everything still works great and the volume control works like a
charm, Now if i also depress button D - this volume control, controls
the speakers on D, however it also controls the speakers on C. BUT the
control on speakers C will not control the speakers on D. Ive double
checked my wiring and nothing is crossed. Could it be something with
the speaker selector -?

It's common for inexpensive speaker switchers (including R.S.)
to wire the speakers in series. This isn't really wonderful
even without autoformer volume controls, but it's a real
(read: very noticable) problem with autoformers.

Here's an interesting experiment: engage (turn "on") the
unused speaker pair B. How many other pairs quit playing?

Do you actually need the ability to switch zones on/off?
If not, you have other options.

All good fortune,

Chris Hornbeck
"It's for compatibility with 8-Track."
-scott"

[[email protected]]

On Apr 28, 7:14 pm, Chris Hornbeck
wrote:
On Mon, 28 Apr 2008 14:15:57 -0700 (PDT), wrote:
2) Radio Shack 40-244 Four way speaker selector (buttons A,B,C and
D)
So here the problem and I hope its not to confusing - I leave button A
always depressed and works great. When I also depress button C
everything still works great and the volume control works like a
charm, Now if i also depress button D - this volume control, controls
the speakers on D, however it also controls the speakers on C. BUT the
control on speakers C will not control the speakers on D. Ive double
checked my wiring and nothing is crossed. Could it be something with
the speaker selector -?

It's common for inexpensive speaker switchers (including R.S.)
to wire the speakers in series. This isn't really wonderful
When I select B the speakers connected to A go quiet. I think that
button is bad. I really do need the ability to turn them on/off.
Should I be looking for a better quality speaker selector or possibly
find instructions that easier for a "beginner" to make?
Thanks
John

even without autoformer volume controls, but it's a real
(read: very noticable) problem with autoformers.

Here's an interesting experiment: engage (turn "on") the
unused speaker pair B. How many other pairs quit playing?

Do you actually need the ability to switch zones on/off?
If not, you have other options.

All good fortune,

Chris Hornbeck
"It's for compatibility with 8-Track."
-scott"

[Chris Hornbeck]

On Mon, 28 Apr 2008 23:06:57 -0700 (PDT), wrote:

When I select B the speakers connected to A go quiet. I think that
button is bad. I really do need the ability to turn them on/off.
Should I be looking for a better quality speaker selector or possibly
find instructions that easier for a "beginner" to make?

The button is not "bad"; they're connected in series. Probably
C and D are also in series.

If you must have the switches and don't want the interaction,
you might look into a box like the Niles SS-4 that parallels
all outputs and includes 2 Ohm series ("protection") resistors.

If you want to make your own, you'll want two-pole single
throw switches for each speaker pair and a couple of 2 Ohm
50 watt resistors, one in each amplifier "hot" lead. Keep
all left channel grounds together and all right channel
grounds together. Bingo.


All good fortune,

Chris Hornbeck
"It's for compatibility with 8-Track."
-scott