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wardy wardy is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using asplitter

Hi,

Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

I havent set up a system where this many (12) speakers need to be run
by 1 amp before so need your input please so i can learn as much as i
can about running multiple speakers from 1 amp.

Q - Does this sound like the best (and cheapest) solution?
Q - Why did the amp click off when i was trying to join the stereo +
and - outputs to make one mono + cable and one mono - cable?
Q - anything you can teach me about wiring up Multiple speakers from 1
amp using a speaker splitter from your own experience would be great.

Looking forward to your advice.
Thanks
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George's Pro Sound Co. George's Pro Sound Co. is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"wardy" wrote in message
...
Hi,

Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

I havent set up a system where this many (12) speakers need to be run
by 1 amp before so need your input please so i can learn as much as i
can about running multiple speakers from 1 amp.

Q - Does this sound like the best (and cheapest) solution?
Q - Why did the amp click off when i was trying to join the stereo +
and - outputs to make one mono + cable and one mono - cable?
Q - anything you can teach me about wiring up Multiple speakers from 1
amp using a speaker splitter from your own experience would be great.

Looking forward to your advice.
Thanks


there are ways to make what your trying to do work,but in reality you have
the wrong equipment, time to list it on ebay and get a 70.7 volt amp and
70.7 volt speakers
it will make the job simple, traceable in your absence and upgradeable
you are trying to use spray cans to paint a house
yes it can be done, the results will be costly, time consuming and
unsatisfactory in the long run
George


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John Williamson John Williamson is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp usinga splitter

wardy wrote:
Hi,

Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

Protection circuit doing what it's supposed to do. Grin

If you want mono, combine the channels at the input. Connecting the
outputs of a stereo amp together is likely to cause damage.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

An easy/ cheap way is to just set up the speakers in series and parallel
connection so the impedance matches what the amp wants to see. In this
case, four series chains of three speakers each *should* be OK.

Impedance shown to amp = (Number of speakers in chain * impedance of
each speaker)/ Number of chains. In this case, two chains of three 8 ohm
speakers per channel would show 12 ohms (nominal) to the amp. Three
chains of two per channel would show a fraction over 5 ohms, which may
or may not be safe.

The easiest way would probably be to go for a 70 or 100 volt line
system. This also gives you the opportunity to easily individually
control the volume from each speaker. You can even turn speakers off
locally if desired without causing problems.

You'd need to buy the right amp, then just parallel the speaker
transformers, up to the available power.

--
Tciao for Now!

John.
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Laurence Payne[_2_] Laurence Payne[_2_] is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

On Fri, 26 Mar 2010 07:08:54 -0700 (PDT), wardy
wrote:

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.


You can series/parallel the speakers to present an acceptable load to
the amplifier. But it's a kludge, and a fault in one speaker or one
connection will very likely bring the whole system down.

The right way to do it is with 70v speakers.
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Scott Dorsey Scott Dorsey is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using asplitter

wardy wrote:
I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.


Throw the splitters away. Purchase some 70V transformers. There is a nice
discussion in the Yamaha Sound Reinforcement Handbook about how 70V systems
work. You will be much happier and things will actually work.
--scott

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


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Bob Urz Bob Urz is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp usinga splitter

wardy wrote:
Hi,

Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

I havent set up a system where this many (12) speakers need to be run
by 1 amp before so need your input please so i can learn as much as i
can about running multiple speakers from 1 amp.

Q - Does this sound like the best (and cheapest) solution?
Q - Why did the amp click off when i was trying to join the stereo +
and - outputs to make one mono + cable and one mono - cable?
Q - anything you can teach me about wiring up Multiple speakers from 1
amp using a speaker splitter from your own experience would be great.

Looking forward to your advice.
Thanks


Hack method:

get two 70 volt line transformers of a equal or slightly larger capacity
of your output power per channel and hook them up backward to the output
terminals of you amplifier to convert it to a 70 volt amp. Then use
speakers with 70 volt line transformers on them. You got a 50% chance
your amplifier might not like the load and blow, but your a gambling man
are you?

Hack method 2:
you find speakers with dual 25v/70volt transformers. You tap the 25V
taps so the combined impedance does not exceed the lowest rating of the
amplifier. 6 per side. Again, you have a 50% chance your amp may not
like the load and say bye.


Hack method 3:

you put on your rubber nose and glasses and go down to Radio Shack and
buy the best Micronta or such PA amp and speakers.



Right method:

Get a mono professional 70 volt line out amplifier and do it right.
Make sure your using the proper code rated wire to hook them up.

bob
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GregS[_3_] GregS[_3_] is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using asplitter

In article , wardy wrote:
Hi,

Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

I havent set up a system where this many (12) speakers need to be run
by 1 amp before so need your input please so i can learn as much as i
can about running multiple speakers from 1 amp.

Q - Does this sound like the best (and cheapest) solution?
Q - Why did the amp click off when i was trying to join the stereo +
and - outputs to make one mono + cable and one mono - cable?
Q - anything you can teach me about wiring up Multiple speakers from 1
amp using a speaker splitter from your own experience would be great.

Looking forward to your advice.
Thanks


To use what you have, wire up the stereo splitter, and push mono switch.
Or, wire up the mono splitter, with ONE channel, and push mono.
Its still a lot of speakers. What is the splitter ? Its got to be a box
of good size with many resistors inside, else you can't use just a
little adaptor plug. Like this................
http://www.altex.com/Vanco-Deluxe-6-...6-P141825.aspx

greg
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Hank[_2_] Hank[_2_] is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using asplitter

In article ,
wardy wrote:
Hi,

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

If you want to drive 12 speakers from a stereo amplifier, set up a pair
of 25 or 70-volt systems on the amplifier outputs. You've got two
amplifiers in the box, use them independently and don't try to tie them
together at the output.

If you want mono operation, just Y the inputs from your signal source to
the two inputs to the two amplifiers.

Hank
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Laurence Payne[_2_] Laurence Payne[_2_] is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

On Fri, 26 Mar 2010 09:20:12 -0700 (PDT), wardy
wrote:

thanks for all the replies so far.
I have to work with the hardware I've got though, so cannot change to
a 70v amp or speakers.


Why? If someone's made a mistake, better to own up and take the loss
than to put in a flaky system.
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William Sommerwerck William Sommerwerck is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

You're going about it the wrong way. You don't need a splitter. (I don't
even know what that is.)

Assuming you can use both channels, and you have a mono signal...

Put six speakers on each channel. A series-parallel arrangement -- three in
series, paralleled with another three in series -- would probably be the
best way, but this depends on the speaker impedance and the minimum load the
amp can drive.

The speakers should be identical. Otherwise you're going to run into level
and other problems.




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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

On Fri, 26 Mar 2010 09:20:12 -0700 (PDT), wardy
wrote:

thanks for all the replies so far.
I have to work with the hardware I've got though, so cannot change to
a 70v amp or speakers.


Then just keep taking your money and flushing it down the toilet buying
more cheap crap to try and compensate for the deficiencies of the cheap
crap you've already bought.

It will wind up costing you a lot more money than just doing it right.

There's no reason you can't use the existing speakers or amps with a 70V
system, though. It just takes transformers. They will cost you more than
buying crappy resistive splitter boxes, but they will actually work reliably,
won't put an excessive stress on the amplifier, won't waste power, and won't
burn up the way the resistive splitters will.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"wardy" wrote in message
...
Hi,

Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

I havent set up a system where this many (12) speakers need to be run
by 1 amp before so need your input please so i can learn as much as i
can about running multiple speakers from 1 amp.

Q - Does this sound like the best (and cheapest) solution?
Q - Why did the amp click off when i was trying to join the stereo +
and - outputs to make one mono + cable and one mono - cable?
Q - anything you can teach me about wiring up Multiple speakers from 1
amp using a speaker splitter from your own experience would be great.

Looking forward to your advice.
Thanks


This is the point where someone experienced says "You did WHAT?"

All 100% the wrong way to go about it.

The best solution is a constant voltage line.

A tansformer is used to steup up the amp's output.

The smaller transformers are used at the speakers.

I recommend Edcor transformers..

Google "constant voltage line" and read. Also read the tech stuff at Edcor.

The transformers for the speakers will have taps if you need to adjust
individual volumes.

The amp transformer has to be sized to accept the full power of the amp. I
don't think the speaker transformer ratings are gonna matter much in your
app. They should be 1/6 of th amp's rating assuming 6 per channel.


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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"wardy" wrote in message
...
On Mar 26, 2:36 pm, Dick Pierce wrote:

however you lost me with the RCA Y splitter.
havent used one of these before.
can you explain more about this to me?
what does it achieve?

Makes the amp mono

also, i would like to use the stereo splitter because it allows
control over turning certain speakers off in rooms.
is there any way of incorporating this into your suggested setup?

thanks again

The only issue with Dick's reply is gonna be how long the speaker lines are.

At 5 ohms a 1 ohm cable resistance is eating 205 of your barely adequate
power.

You can add 70 volt transformers to your stuff so be careful, the conclusion
you jump to may be your own.

Two good trannies for the amp and a dozen cheapies won't cost a lot. And is
the BEST way.

If you only need short wires, by all means Dick's suggestion is fast and
cheap.

However 3 adjectives usually apply. Fast, cheap, good.

And usually you can only pick two.

The steroe splitter, if it has 3 outputs, can be used with dicks suggestion
just put each pair on an output.

With all 3 on it is a 5 ohm load, 2 on a 8 ohm load, and only one pair a 16
ohm load. I am assuming none of those is an issue for your amp.

If you only have two out fron the splitter, you will have to decide which
two pairs can work together,

When asking this stuff you will get much better advice by posting make and
model

"splitter' is a pretty baoad category, am assuming you mean a basic speaker
switch.


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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"Laurence Payne" wrote in message
...
On Fri, 26 Mar 2010 09:20:12 -0700 (PDT), wardy
wrote:

thanks for all the replies so far.
I have to work with the hardware I've got though, so cannot change to
a 70v amp or speakers.


Why? If someone's made a mistake, better to own up and take the loss
than to put in a flaky system.


He's also wrong. all he needs to do is add transformers. Done it a hundred
times.


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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"liquidator"

He's also wrong. all he needs to do is add transformers. Done it a hundred
times.


** Really ?? Not with domestic amps like Technics.

Such amps are never intended to drive 70 volt line ( step up) transformers
are very likely to be damaged by so doing.

The issue is core saturation at low frequencies - hard to avoid
completely and deadly on anything but the most rugged amplifiers.


...... Phil









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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"Phil Allison" wrote in message
...

"liquidator"

He's also wrong. all he needs to do is add transformers. Done it a
hundred times.


** Really ?? Not with domestic amps like Technics.

Such amps are never intended to drive 70 volt line ( step up) transformers
are very likely to be damaged by so doing.

The issue is core saturation at low frequencies - hard to avoid
completely and deadly on anything but the most rugged amplifiers.


..... Phil



Interesting. Have done it dozens of times. Tend not to use Technics, and do
use quality transformers.

What about a coupling capacitor or would that be a bad idea?

You are the one whose judgement I respect, perhapsI have just been lucky.


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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"liquidator"
"Phil Allison"
"liquidator"

He's also wrong. all he needs to do is add transformers. Done it a
hundred times.


** Really ?? Not with domestic amps like Technics.

Such amps are never intended to drive 70 volt line ( step up)
transformers are very likely to be damaged by so doing.

The issue is core saturation at low frequencies - hard to avoid
completely and deadly on anything but the most rugged amplifiers.


Interesting. Have done it dozens of times. Tend not to use Technics, and
do use quality transformers.

What about a coupling capacitor or would that be a bad idea?


** An electro cap of about 1000uF ( a back to back pair is needed ) will at
least eliminate any DC offset issues with the very low primary resistance of
the line tranny - but adds the risk of creating a low frequency series
resonance effects which can be even more deadly to the amp.


You are the one whose judgement I respect, perhapsI have just been lucky.


** You must have been extraordinarily lucky.

It is reckless to connect a domestic or even most pro audio amp's output
direct to a line voltage tranny - amp makers regularly warn against it.
Generally, the amp requires modification and a network is placed between the
amp and the tranny to limit current flow to a safe value if core saturation
or overload occurs.

QSC amps are particularly vulnerable to damage when used this way - seen 4
of them ( USA850s ) destroyed on the same day the install was done.



...... Phil


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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"Phil Allison" wrote in message
...

"liquidator"
"Phil Allison"
"liquidator"

He's also wrong. all he needs to do is add transformers. Done it a
hundred times.

** Really ?? Not with domestic amps like Technics.

Such amps are never intended to drive 70 volt line ( step up)
transformers are very likely to be damaged by so doing.

The issue is core saturation at low frequencies - hard to avoid
completely and deadly on anything but the most rugged amplifiers.


Interesting. Have done it dozens of times. Tend not to use Technics, and
do use quality transformers.

What about a coupling capacitor or would that be a bad idea?


** An electro cap of about 1000uF ( a back to back pair is needed ) will
at least eliminate any DC offset issues with the very low primary
resistance of the line tranny - but adds the risk of creating a low
frequency series resonance effects which can be even more deadly to the
amp.


You are the one whose judgement I respect, perhapsI have just been lucky.


** You must have been extraordinarily lucky.

It is reckless to connect a domestic or even most pro audio amp's output
direct to a line voltage tranny - amp makers regularly warn against it.
Generally, the amp requires modification and a network is placed between
the amp and the tranny to limit current flow to a safe value if core
saturation or overload occurs.

QSC amps are particularly vulnerable to damage when used this way - seen
4 of them ( USA850s ) destroyed on the same day the install was done.



..... Phil



I've seen USA series QSC's disintegrate in normal use.

Never cared for that amp.

Most of the time it was an MI grade system some bar owner bought and was
stuck with.

Towards the end I was specing the CX series QSC, the V models are optimized
to drive lines without a transformer. That does change the wiring spec in
Ohio though, if it is not transformer coupled wiring must be armored.


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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"liquidator"


I've seen USA series QSC's disintegrate in normal use.


** Really ??

The example I gave involved 4 brand new amps failing SIMULTANEOUSLY on
the first day of use.


Never cared for that amp.


** Who cares what amps you are infatuated or not with ?



...... Phil


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Scott Dorsey Scott Dorsey is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

liquidator wrote:
"Phil Allison" wrote in message
...

"liquidator"

He's also wrong. all he needs to do is add transformers. Done it a
hundred times.


** Really ?? Not with domestic amps like Technics.

Such amps are never intended to drive 70 volt line ( step up) transformers
are very likely to be damaged by so doing.

The issue is core saturation at low frequencies - hard to avoid
completely and deadly on anything but the most rugged amplifiers.


Interesting. Have done it dozens of times. Tend not to use Technics, and do
use quality transformers.


Wow. I had no idea Phil was still around! But yes, I have done it plenty
of times, even using some pretty shoddy amps based on STK modules (like
those Rane 1U power amps) and never had a problem. But I could see there
being an issue with undersized output transformers if you aren't filtering
the input of the amp.

I have generally designed 70v systems for high quality audio to have a
-3 dB point around 20 Hz, which requires pretty huge transformers. I
strongly recommend the Tannoy transformers (which are actually made by
some company in Canada for them) but the cheap Edcors aren't bad if you
buy their "extended low frequency" series. For background music systems
there's no need to have anything that extreme.

What about a coupling capacitor or would that be a bad idea?


Bad idea if you put it after the amp, because the amp does not like driving
capacitive loads. But put a filter before the amp so the amp never puts
low frequencies into the system, and you'll be fine. Oh yes, and PLEASE
use a fuse on the input to the step-up. This will save you some day when
someone shorts out the wiring.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."


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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"Phil Allison" wrote in message
...

** Who cares what amps you are infatuated or not with ?

0
That time of the month Phil?


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Phil Allison[_3_] Phil Allison[_3_] is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"Scott Dorsey"
"Phil Allison"

** Really ?? Not with domestic amps like Technics.

Such amps are never intended to drive 70 volt line ( step up)
transformers
are very likely to be damaged by so doing.

The issue is core saturation at low frequencies - hard to avoid
completely and deadly on anything but the most rugged amplifiers.



Wow. I had no idea Phil was still around! But yes, I have done it plenty
of times, even using some pretty shoddy amps based on STK modules (like
those Rane 1U power amps) and never had a problem.



** How dishonest.

Rane's 4ch 1RU amps are specifically designed to drive line transformers
with ELABORATE inbuilt filtering and limiting - an optional 1RU box with
4 toroidal line trannies goes with these amps.

http://www.rane.com/ma4.html



But I could see there
being an issue with undersized output transformers if you aren't filtering
the input of the amp.


** All transformers suffer from core saturation, larger ones just do it at
lower frequencies than smaller ones.

No matter how big the step-up transformer is - there are still all those
puny distributed ones at each speaker location, most of which saturate hard
at 70 to 80 Hz with nominal voltage input. The gross overload effect
thereby created is naturally reflected straight back to the poor suffering
amplifier.


What about a coupling capacitor or would that be a bad idea?


Bad idea if you put it after the amp, because the amp does not like
driving
capacitive loads.


** Nonsense.

SS amps used output coupling caps since they were first invented with no
such problem.


But put a filter before the amp so the amp never puts
low frequencies into the system, and you'll be fine.


** Such high pass filters really need to be built into the power amp to be
reliably effective - plus have a steep slope like 18 to 24 dB/ octave and
start rolling of at around 90 to 100 Hz.

External filters can still result in serious problems with switch on and off
thumps.

Rane seem to be well aware of all the issues.

http://www.rane.com/pdf/ma4dat.pdf


..... Phil



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Mr.T Mr.T is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"wardy" wrote in message
...
I have a decent background in sound engineering



From what you've written below, I can't begin to imagine what you call "a
decent background in sound engineening"!!!




and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

I havent set up a system where this many (12) speakers need to be run
by 1 amp before so need your input please so i can learn as much as i
can about running multiple speakers from 1 amp.

Q - Does this sound like the best (and cheapest) solution?
Q - Why did the amp click off when i was trying to join the stereo +
and - outputs to make one mono + cable and one mono - cable?
Q - anything you can teach me about wiring up Multiple speakers from 1
amp using a speaker splitter from your own experience would be great.



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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter


"Soundhaspriority" wrote in message
...
wrote in message

I have generally designed 70v systems for high quality audio to have a
-3 dB point around 20 Hz, which requires pretty huge transformers. I
strongly recommend the Tannoy transformers (which are actually made by
some company in Canada for them)


I thought Tannoys were slang for loudspeakers. What would they have to do
with transformers?


In Britain, just like Hoover is slang for vacuum cleaner. Both because of
the company that makes them being so popular at the time. And both companies
also made other products.

MrT.


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Richard Crowley Richard Crowley is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

"wardy" wrote ...
Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

I havent set up a system where this many (12) speakers need to be run
by 1 amp before so need your input please so i can learn as much as i
can about running multiple speakers from 1 amp.

Q - Does this sound like the best (and cheapest) solution?


No

Q - Why did the amp click off when i was trying to join the stereo +
and - outputs to make one mono + cable and one mono - cable?


You either shorted the L and R outputs together, or you shorted
one (or both) to ground. You are lucky the amp protected itself
else you would have an expensive boat anchor.

Q - anything you can teach me about wiring up Multiple speakers from 1
amp using a speaker splitter from your own experience would be great.


Are all the speakers the same?
What is the impedance (in ohms) of the speakers?
What is the amplifier rating in watts?
What is the lowest safe impedance the amplifier is rated for?
Are you trying to make this a "stereo" system or mono?
Do you need to independently control the level of the speakers?
Do you need to independently switch the speakers on/off?
What sound levels are you expecting? Is this background
music in a dentist office? Or is this warm-up music at a rock
concert?

My practice would be to forget the "splitters" and wire the
speakers in series-parallel to create a safe load for the amp.

Note that the "professional" method is to use "constant voltage"
transformers to safely connect many speakers to a single amp.

If you aren't going to provide model numbers and specs, it
doesn't really make much difference what nameplate (brand-
name) is on the equipment.




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Hank[_2_] Hank[_2_] is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

In article ,
Scott Dorsey wrote:

I have generally designed 70v systems for high quality audio to have a
-3 dB point around 20 Hz, which requires pretty huge transformers. I
strongly recommend the Tannoy transformers (which are actually made by
some company in Canada for them) but the cheap Edcors aren't bad if you
buy their "extended low frequency" series. For background music systems
there's no need to have anything that extreme.

Are those Tannoy transformers wound by Hammond in Ontario?
Hammond's own line is at http://www.hammondmfg.com/117.htm. The top of
their line talks about low frequency cutoff at 50 Hz. at full power.
I think Mouser now carries the Hammond line. Prices, last I looked, are
not too bad, considering that they're about the only quality house
still winding some of the old-spec stuff for vacuum tube iron.

Hank
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Scott Dorsey Scott Dorsey is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

Hank wrote:
In article ,
Scott Dorsey wrote:

I have generally designed 70v systems for high quality audio to have a
-3 dB point around 20 Hz, which requires pretty huge transformers. I
strongly recommend the Tannoy transformers (which are actually made by
some company in Canada for them) but the cheap Edcors aren't bad if you
buy their "extended low frequency" series. For background music systems
there's no need to have anything that extreme.

Are those Tannoy transformers wound by Hammond in Ontario?


No. I had to go down and find one of them, but they are made by BEI
(www.bei.net). Hammond's transformers are... kind of deficient.

Hammond's own line is at http://www.hammondmfg.com/117.htm. The top of
their line talks about low frequency cutoff at 50 Hz. at full power.


That's not anything to write home about, but you could do okay IF you
could derate the things. What you want is something with the same input
and output Z but with a much larger core.

I think Mouser now carries the Hammond line. Prices, last I looked, are
not too bad, considering that they're about the only quality house
still winding some of the old-spec stuff for vacuum tube iron.


That's actually a pretty big market these days, though. Lots of small
outfits doing good work, like Sowter. Sowter also makes 70v transformers
with good numbers too, but I have never tried them.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Klay_Anderson Klay_Anderson is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using asplitter

On Mar 26, 8:08*am, wardy wrote:
Hi,

Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.



I'd suggest a US company, Edcor. They make matching transformers for
high power 8-ohms-to-70-volt (so you can use that POS Technics) and
vice-versa for step-down at the speaker. They also make line- and mic-
level transformers and other goodies. Nice folks and you can order
direct.

Text "Klay" to 50500 for contact info

-.- .-.. .- -.-- / .- - / -.- .-.. .- -.-- / -.. --- - / -.-. --- --
Yours truly,

Mr. Klay Anderson, D.A.,Q.B.E.
Klay Anderson Audio, Inc.
http://www.klay.com
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Peter Larsen[_3_] Peter Larsen[_3_] is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using a splitter

Klay_Anderson wrote:

On Mar 26, 8:08 am, wardy wrote:
Hi,


Advice needed please from all you experts out there.


I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.


I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across
a sprawling venue.


I'd suggest a US company, Edcor. They make matching transformers for
high power 8-ohms-to-70-volt (so you can use that POS Technics)


Technics is usually not POS, but in the context it may be, in which case it
does not belong in the context.

and
vice-versa for step-down at the speaker. They also make line- and
mic- level transformers and other goodies. Nice folks and you can
order direct.


On the skill level of the original poster the reply is "bite the sour apple,
get a 70 volt amplifier and 70 volt speakers, most "loudenboomer"
manufacturers DO have a line of small 70 volt boxes and diy'ing what can be
bought ready made over the counter tends to be costlier nowadays. Or do the
series parallel wiring suggested, A suggestion once made to me is to
remember to parallel speakers to pairs and series connect the pairs if ever
I had to make such a setup. Starting out with 16 ohm boxes will simply the
setup greatly!

Text "Klay" to 50500 for contact info


No comment.

-.- .-.. .- -.-- / .- - / -.- .-.. .- -.-- / -.. --- - / -.-. --- --
Yours truly,

Mr. Klay Anderson, D.A.,Q.B.E.
Klay Anderson Audio, Inc.
http://www.klay.com


Kind regards

Peter Larsen



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GregS[_3_] GregS[_3_] is offline
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Default Advice needed! - How to run 12 small speakers from 1 amp using asplitter

In article , wardy wrote:
Hi,

Advice needed please from all you experts out there.

I have a decent background in sound engineering and live mic/desk
setups, however I am no expert.
I want to find the best way of installing a particular system in a
public venue.

I am installing a Technics amp with normal Stereo output (+- L and +-
R)
I have to send the audio thru the amp to 12 separate speakers across a
sprawling venue.

I have purchased a mono splitter and a stereo splitter.



I see the other option............

http://tinyurl.com/yaw4b58

Firstly i tried the mono splitter so that each speaker would be mono.
I tried to convert this stereo output from the amp to mono by
combining the cables. firstly i tried to wire both the + outputs from
the amp into the + of 1 speaker cable and both the - into the - of
the cable. this however simply forced the amp to "click" off after a
few seconds of sound so i presume it wasnt happy with the level of
impedance of whatever.
So a mono splitter is out.

I am going to try the 6 way skytronic Stereo splitter next.
I am going to run 2 cables from the amp to the splitter (for L & R)
Then use the L and R channel from each of the 6 "rooms" on the
splitter as a separate L or R speaker on either side of the room thus
giving 12 speakers (6 L and 6 R).

I havent set up a system where this many (12) speakers need to be run
by 1 amp before so need your input please so i can learn as much as i
can about running multiple speakers from 1 amp.

Q - Does this sound like the best (and cheapest) solution?
Q - Why did the amp click off when i was trying to join the stereo +
and - outputs to make one mono + cable and one mono - cable?
Q - anything you can teach me about wiring up Multiple speakers from 1
amp using a speaker splitter from your own experience would be great.

Looking forward to your advice.
Thanks

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