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Nate Najar
January 24th 15, 08:43 AM
If you theoretically had a solid state power amp that had 1/4" speaker outputs but no option to bridge to mono, could you do something internally or externally with wiring to tap both channels to a single speaker output?

John Williamson
January 24th 15, 08:52 AM
On 24/01/2015 08:43, Nate Najar wrote:
> If you theoretically had a solid state power amp that had 1/4" speaker outputs but no option to bridge to mono, could you do something internally or externally with wiring to tap both channels to a single speaker output?
>
Invert one channel's input using a unity gain inverting preamp, then
feed the speaker from both speaker "live" connections. This will result
in either a 3dB power increase, no output at all due to the protection
circuitry cutting in or the escape of the magic smoke, depending on the
amplifier design. Some amplifiers already use bridging to drive the
speakers anyway as it lets them use twice as many output transistors
that cost a quarter of the price each, they just don't always admit it.

It is very unlikely to sound noticeably louder than using it as two
channels with two speakers, and two speakers can be aimed to get better
distribution.

--
Tciao for Now!

John.

John Williamson
January 24th 15, 09:13 AM
On 24/01/2015 08:52, John Williamson wrote:
> On 24/01/2015 08:43, Nate Najar wrote:
>> If you theoretically had a solid state power amp that had 1/4" speaker
>> outputs but no option to bridge to mono, could you do something
>> internally or externally with wiring to tap both channels to a single
>> speaker output?
>>
> Invert one channel's input using a unity gain inverting preamp, then
> feed the speaker from both speaker "live" connections. This will result
> in either a 3dB power increase, no output at all due to the protection
> circuitry cutting in or the escape of the magic smoke, depending on the
> amplifier design. Some amplifiers already use bridging to drive the
> speakers anyway as it lets them use twice as many output transistors
> that cost a quarter of the price each, they just don't always admit it.
>
> It is very unlikely to sound noticeably louder than using it as two
> channels with two speakers, and two speakers can be aimed to get better
> distribution.
>
Forgot to add. The speaker impedance will need to be doubled to keep the
output stages within their current limits, so if it normally uses 4 ohm
speakers on each channel, the single speaker needs to be 8 ohms, and so on.

--
Tciao for Now!

John.

Peter Larsen[_3_]
January 24th 15, 09:39 AM
"Nate Najar" > skrev i en meddelelse
...

> If you theoretically had a solid state power amp that
> had 1/4" speaker outputs but no option to bridge to mono,
> could you do something internally or externally with wiring
> to tap both channels to a single speaker output?

Err on the side of caution and assume that if the manufacturer intended the
poweramp for bridging he would supply the paraphernalia.

LD Systems btw. has at least one model that is audiophile grade at disco-kid
price. I found the physiotherapists training amp so well sounding that I
bought a similar one second hand, it was a good bet. They no longer make
that specific model but I'd give their stuff a serious listen if I needed
more amplifiers.

Kind regards

Peter Larsen

Scott Dorsey
January 24th 15, 12:24 PM
Nate Najar > wrote:
>If you theoretically had a solid state power amp that had 1/4" speaker outputs but no option to bridge to mono, could you do something internally or externally with wiring to tap both channels to a single speaker output?

IF both outputs have a common ground, which is to say it's not already bridged
internally, then you can drive the two inputs with a Y cable where pins 2 and 3
are swapped on one leg so the output is reverse polarity.

Now you have two outputs out of polarity, you bridge the load between them.

Now... that said... I have never seen a power amp with 1/4" speaker outputs
and the idea is kind of scary. It's horrible enough that people use those
things as speaker inputs.
--scott

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

Mike Rivers[_2_]
January 24th 15, 01:38 PM
On 1/24/2015 7:24 AM, Scott Dorsey wrote:
> I have never seen a power amp with 1/4" speaker outputs
> and the idea is kind of scary.

How could you be so lucky as to never have worked at a folk festival in
the 15 years between about 1975 and 1990 where there was always a Peavey
system or three? Just about all portable powered mixers have 1/4" jacks
for the speakers, and Switchcraft (and probably others) make a plug with
a fat shell so you can wire them together with 12 gauge cable.



--
"Today's production equipment is IT based and cannot be operated without
a passing knowledge of computing, although it seems that it can be
operated without a passing knowledge of audio" - John Watkinson

Drop by http://mikeriversaudio.wordpress.com now and then

Les Cargill[_4_]
January 24th 15, 08:11 PM
(Scott Dorsey) wrote:
> Nate Najar > wrote:
>> If you theoretically had a solid state power amp that had 1/4" speaker outputs but no option to bridge to mono, could you do something internally or externally with wiring to tap both channels to a single speaker output?
>
> IF both outputs have a common ground, which is to say it's not already bridged
> internally, then you can drive the two inputs with a Y cable where pins 2 and 3
> are swapped on one leg so the output is reverse polarity.
>
> Now you have two outputs out of polarity, you bridge the load between them.
>
> Now... that said... I have never seen a power amp with 1/4" speaker outputs
> and the idea is kind of scary.

Wow, really? Not the "scary" part, the "never seen" part.

No Peavey for Scott :) Modern Peavey does have Speakon.
Speakon is annoying because it doesn't seem to support
daisy-chaining in the same way 1/4" did.


> It's horrible enough that people use those
> things as speaker inputs.
> --scott
>

--
Les Cargill

Frank Stearns
January 24th 15, 09:00 PM
Les Cargill > writes:

(Scott Dorsey) wrote:
>> Nate Najar > wrote:

snips

>Speakon is annoying because it doesn't seem to support
>daisy-chaining in the same way 1/4" did.

Really? Isn't this just the whim of the manufacturer? When I wear my PA mixer hat,
I've seen and used a lot of stage monitors that include two speakons for daisy
chaining. They're internally Y'd, just like the old days of 1/4".

And I too really dislike 1/4" for most applications; 100x the hatred for 1/8".
If I were king, I'd outlaw both. But then, how do we get a speakon or even an XLR on
a laptop or smartphone? :)

Frank
Mobile Audio
--

Les Cargill[_4_]
January 24th 15, 10:40 PM
Frank Stearns wrote:
> Les Cargill > writes:
>
>> (Scott Dorsey) wrote:
>>> Nate Najar > wrote:
>
> snips
>
>> Speakon is annoying because it doesn't seem to support
>> daisy-chaining in the same way 1/4" did.
>
> Really? Isn't this just the whim of the manufacturer?

Possibly. I have run into some gear that has only the one, and
wye cables are hard to find.

> When I wear my PA mixer hat,
> I've seen and used a lot of stage monitors that include two speakons for daisy
> chaining. They're internally Y'd, just like the old days of 1/4".
>

I wish more would do that.

> And I too really dislike 1/4" for most applications; 100x the hatred for 1/8".
> If I were king, I'd outlaw both. But then, how do we get a speakon or even an XLR on
> a laptop or smartphone? :)
>

You don't. Well, with something connected USB.

> Frank
> Mobile Audio
>

--
Les Cargill

Frank Stearns
January 25th 15, 12:52 AM
Les Cargill > writes:

>Frank Stearns wrote:
>> Les Cargill > writes:
>>
>>> (Scott Dorsey) wrote:
>>>> Nate Najar > wrote:
>>
>> snips
>>
>>> Speakon is annoying because it doesn't seem to support
>>> daisy-chaining in the same way 1/4" did.
>>
>> Really? Isn't this just the whim of the manufacturer?

>Possibly. I have run into some gear that has only the one, and
>wye cables are hard to find.

It's probably because for lower-end commodity manufacturers, a 1/4" panel female is
around 30 cents or even less. They might put in a second one and not grumble too
much, whereas a speakon might be 3-5 times that and they won't because that second
connector would break the parts budget for the device. (Yes, those types of
manufacturers are just that cheap.)

Or, if they sell the stuff with their amps, they don't want you thoughtlessly
chaining enough speakers to pull the amp load down into the smoke zone.)

Speakon Y cables are easy to make (one of the nice things is the working room you
have inside the connector). I had to make up several for the monitor amp patch panel
at the theater where I do the occasional gig. Very easy to put those together.

If you want to buy them, do a web-search on "Speakon Y cables". You'll get a fair
number of hits.

Be aware, though, that you'll probably need speakon barrels to go with those Ys.
From what I've seen, by convention speakon panel mounts appear to be one sex only,
and speakon cable mounts appear to be only the opposite sex. But you can get
same-sex barrels to take are of cable-to-cable connections, as you'd have on two
legs of the Y.


>> When I wear my PA mixer hat,
>> I've seen and used a lot of stage monitors that include two speakons for daisy
>> chaining. They're internally Y'd, just like the old days of 1/4".

>I wish more would do that.

My sense is that most commercial-grade units will have the two connectors.

But, as always, YMMV.

Frank
Mobile Audio

--

geoff
January 25th 15, 02:54 AM
On 25/01/2015 9:11 a.m., Les Cargill wrote:

>
> No Peavey for Scott :) Modern Peavey does have Speakon.
> Speakon is annoying because it doesn't seem to support
> daisy-chaining in the same way 1/4" did.

Why ever not ?


geoff

Les Cargill[_4_]
January 25th 15, 04:21 AM
geoff wrote:
> On 25/01/2015 9:11 a.m., Les Cargill wrote:
>
>>
>> No Peavey for Scott :) Modern Peavey does have Speakon.
>> Speakon is annoying because it doesn't seem to support
>> daisy-chaining in the same way 1/4" did.
>
> Why ever not ?
>
>
> geoff


Cost, I am sure.

--
Les Cargill

Peter Larsen[_3_]
January 25th 15, 07:31 AM
"Les Cargill" > skrev i en meddelelse
...


>>> Speakon is annoying because it doesn't seem to support
>>> daisy-chaining in the same way 1/4" did.

>> Really? Isn't this just the whim of the manufacturer?

> Possibly. I have run into some gear that has only the one, and
> wye cables are hard to find.

>> When I wear my PA mixer hat,
>> I've seen and used a lot of stage monitors that include two speakons for
>> daisy
>> chaining. They're internally Y'd, just like the old days of 1/4".

> I wish more would do that.

The only boxes I have seen without dual sockets for parallel output -
strictly speaking I understand daisy chain as series connection - have been
owner upgrades.

> Les Cargill

Kind regards

Peter Larsen

Peter Larsen[_3_]
January 25th 15, 07:31 AM
"Les Cargill" > skrev i en meddelelse
...

> geoff wrote:
>> On 25/01/2015 9:11 a.m., Les Cargill wrote:

>>> No Peavey for Scott :) Modern Peavey does have Speakon.
>>> Speakon is annoying because it doesn't seem to support
>>> daisy-chaining in the same way 1/4" did.

>> Why ever not ?

>> geoff

> Cost, I am sure.

Impossible. The cheapest stuff from a cave in China has dual Speakons. It
probably costs extra to get boxes with only one.

> Les Cargill

Kind regards

Peter Larsen

Scott Dorsey
January 25th 15, 12:39 PM
Les Cargill > wrote:
>
>No Peavey for Scott :) Modern Peavey does have Speakon.
>Speakon is annoying because it doesn't seem to support
>daisy-chaining in the same way 1/4" did.

The main experience I had with Peavey was watching someone forklifting
Peavey stacks off a loading dock, shouting about how the rider did not
allow Peavey gear.
--scott

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

Scott Dorsey
January 25th 15, 12:40 PM
Les Cargill > wrote:
>> Really? Isn't this just the whim of the manufacturer?
>
>Possibly. I have run into some gear that has only the one, and
>wye cables are hard to find.

It'll take you ten minutes to make a Speakon Y, and you don't even need
a soldering iron, just a small screwdriver. You should have a bunch of
them in the kit, along with some barrel connectors and a few Speakon-to-Banana
cables.

>> And I too really dislike 1/4" for most applications; 100x the hatred for 1/8".
>> If I were king, I'd outlaw both. But then, how do we get a speakon or even an XLR on
>> a laptop or smartphone? :)

They aren't 1/8" connectors, they are 3.5mm. And the laptops and smartphones
in a perfect world would have LEMO locking connectors.
--scott

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

Mike Rivers[_2_]
January 25th 15, 01:35 PM
On 1/25/2015 4:40 AM, Scott Dorsey wrote:
> They aren't 1/8" connectors, they are 3.5mm. And the laptops and smartphones
> in a perfect world would have LEMO locking connectors.

Dream on! One of the few useful pieces of information I got from the
NAMM show this year is that those manufacturers want to build thinner
and thinner devices. They're using the Lightning port not because it's
faster than USB, nor because it'll carry HDMI video, but because it's
thinner and they can make the case thinner because of it.

It's not all that important that we'll now need a new suite of cables,
or maybe hardware, to connect to it. Snot their problem.

--
"Today's production equipment is IT based and cannot be operated without
a passing knowledge of computing, although it seems that it can be
operated without a passing knowledge of audio" - John Watkinson

Drop by http://mikeriversaudio.wordpress.com now and then

Les Cargill[_4_]
January 25th 15, 04:48 PM
Peter Larsen wrote:
> "Les Cargill" > skrev i en meddelelse
> ...
>
>> geoff wrote:
>>> On 25/01/2015 9:11 a.m., Les Cargill wrote:
>
>>>> No Peavey for Scott :) Modern Peavey does have Speakon.
>>>> Speakon is annoying because it doesn't seem to support
>>>> daisy-chaining in the same way 1/4" did.
>
>>> Why ever not ?
>
>>> geoff
>
>> Cost, I am sure.
>
> Impossible. The cheapest stuff from a cave in China has dual Speakons. It
> probably costs extra to get boxes with only one.
>

Dunno what to tell you, Peter - I've run into a run of gear ( for
my purposes, anyway - I don't get to view all that much equipment )
that has only the one.

Perhaps this was more of a thing ten years ago.

>> Les Cargill
>
> Kind regards
>
> Peter Larsen
>
>
>
>

--
Les Cargill

Frank Stearns
January 25th 15, 07:13 PM
"Peter Larsen" > writes:

>"Les Cargill" > skrev i en meddelelse
...

snips

>The only boxes I have seen without dual sockets for parallel output -
>strictly speaking I understand daisy chain as series connection - have been
>owner upgrades.

Series??! I think you meant parallel....

Frank
Mobile Audio



--

Peter Larsen[_3_]
January 27th 15, 07:37 AM
"Les Cargill" > skrev i en meddelelse
...

> Peter Larsen wrote:


>>> Cost, I am sure.

>> Impossible. The cheapest stuff from a cave in China has dual Speakons. It
>> probably costs extra to get boxes with only one.

> Dunno what to tell you, Peter - I've run into a run of gear ( for
> my purposes, anyway - I don't get to view all that much equipment )
> that has only the one.

Strange, I had 1 Behringer 1220F and 4 1220 B's (first version, with real
compression driver for top) as supplementary speakers in my horseshow setup
that all had dual Speakons and that is about as cheap chinese stuff as you
can find it.

> Perhaps this was more of a thing ten years ago.

Could be, it could also be that Behringer is less unprofessional than some
claim, the market may have changed, the pinstripes may have won and now rule
the world ... but at least yesterdays asteroid missed by a furlong and half
a home-run.

> Les Cargill

Kind regards

Peter Larsen

Peter Larsen[_3_]
January 27th 15, 07:40 AM
"Frank Stearns" > skrev i en meddelelse
...

> "Peter Larsen" > writes:

>> The only boxes I have seen without dual sockets for parallel output -
>> strictly speaking I understand daisy chain as series connection - have
>> been
>> owner upgrades.

> Series??! I think you meant parallel....

Yes, the dual speakons are for parallel and yes, I mean that daisy chain is
series, I have seen it done with stage monitors in the old days when
amplifiers didn't like low impendance loads.

> Frank
> Mobile Audio

Kind regards

Peter Larsen

Trevor
January 27th 15, 07:44 AM
On 25/01/2015 7:11 AM, Les Cargill wrote:
> (Scott Dorsey) wrote:

>> Now... that said... I have never seen a power amp with 1/4" speaker
>> outputs and the idea is kind of scary.

Good for the amplifier repairers though I guess :-)


> No Peavey for Scott :) Modern Peavey does have Speakon.
> Speakon is annoying because it doesn't seem to support
> daisy-chaining in the same way 1/4" did.

You are kidding right? Nearly all my speakers have two sets of speakons
for daisy chaining. Would NEVER use 1/4 for speakers!

Trevor.

Les Cargill[_4_]
January 27th 15, 11:53 PM
Trevor wrote:
> On 25/01/2015 7:11 AM, Les Cargill wrote:
>> (Scott Dorsey) wrote:
>
>>> Now... that said... I have never seen a power amp with 1/4" speaker
>>> outputs and the idea is kind of scary.
>
> Good for the amplifier repairers though I guess :-)
>
>
>> No Peavey for Scott :) Modern Peavey does have Speakon.
>> Speakon is annoying because it doesn't seem to support
>> daisy-chaining in the same way 1/4" did.
>
> You are kidding right?

No, quite serious.

> Nearly all my speakers have two sets of speakons
> for daisy chaining. Would NEVER use 1/4 for speakers!
>

I'm thinking this was perhaps more of a problem in years past. Remember,
I'm not a sound tech - most of my exposure to other people's gear is as
a player. I'm also thinking that the cheap MI guys went through a
transition period where they supplied 1/4" and Speakon, so panel
space was perhaps a constraint.

But I really don't know why.

I had a run of a handful of years where everything I ran into that had
Speakon only had the one. This was weekend-warrior stuff where
the band brought their own PA.

I've never had a problem with 1/4" speaker cables & jacks ( over a span
of geez, a long time now - off and on for forty years ) - and I
mean no problems - but I can certainly understand why you wouldn't want
to go that way.

> Trevor.
>
>

--
Les Cargill

Peter Larsen[_3_]
January 28th 15, 04:57 AM
"Les Cargill" > skrev i en meddelelse
...

> I had a run of a handful of years where everything I ran into that had
> Speakon only had the one. This was weekend-warrior stuff where
> the band brought their own PA.

I submit that those boxes probably were owner upgrades.

> Les Cargill

Kind regards

Peter Larsen