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Title: Bridged amps and stereo playback
Post by: Jeffrey l jones on October 13, 2016, 11:35:18 PM
If I decided to bridge my FOH amps (1) for tops (1) for subs, I'll only need to use one (1) main slider. Say the LEFT slider. Do I then pan all Mic channels,DI boxes ect to the LEFT?
Also, what about the RCA stereo channels at the end of my board I use for playback music between sets? I have (2) set of RCA channels like that. Can I put Red RCA in red left then pan left, Then put White RCA in next channel red left , then pan left? Would that get my stereo playback at least back to where I can hear the FULL song? You know 1/2 of it missing?
Title: Re: Bridged amps and stereo playback
Post by: Jeff Bankston on October 14, 2016, 12:04:35 AM
pan left or right and use the corresponding main out slider. plug a Y cable into your music playback device and plug it into the jack of the side you are using. thats what i do. I have 1 main out and i use 1 main out fader.
Title: Re: Bridged amps and stereo playback
Post by: Tim Halligan on October 14, 2016, 12:52:29 AM
Alternatively, you could mix in stereo, then Y-cord your main outputs so the amps see a single input, but you have the option of making stereo board tapes from your alternate output when required.

HTH

Cheers,
Tim
Title: Re: Bridged amps and stereo playback
Post by: Luke Geis on October 14, 2016, 02:18:21 AM
I say it depends on the mixer and it's channel stereo bussing type. Some mixers ( most actually, but not all ) use a gain blending pan pot. As you pan it more to one side or the other it will increase gain to " make up " for the lack of apparent gain as to when the two channels are summed to mono. You don't notice the increase in gain as much when amplified through a stereo system, but in a mono one you can hear the channel get louder as you pan it to the side that is being amplified. Not a big deal, but you may find that eat up more headroom sooner panning everything to one side, simply because of that make up gain.

Now as to summing a stereo music feed into mono, the best way I have found is to use multiple channels. If you have two stereo music sources, you will need 4 channels. All of them can be panned up the middle if you use the L / Mono input on the stereo inputs.

As to the amps, yes you are correct except one thing. If you set the amps up in bridge mono mode, one half of the amp will be out of phase, so you must connect the speakers correctly to accommodate that. That is, you must connect the output of the amp to both the red terminals with channel one typically being the positive side of the bridge connection. The speakers will be connected in parallel being sure that the total load does not go below 4 ohms. If you are going to connect two speakers to the same amp not using a special connector, then you will have to reverse the connection to the second channel of the amp by flipping pin 1 and 2. If you don;e understand what I mean let me clarify:

1. A bridge mono amp setting inverts the polarity of its second channel to make its red terminal negative in relation to the first channel.

2. When you connect a speaker to a bridge mono amp, you connect the positive terminal to channel one and the negative terminal to channel two.

3. Some, not all amps, will convert the terminals for you, so you do not need a special connector to make a bridge connection. If your amp does not do this you either have to connect the wires directly, or use a connector that has the speaker wires connected to the proper terminals ( easiest done with a Banana to speak-on connector wired appropriately ). Most ( again not all ) amps have all 4 pin connections off the channel ones NL4 output, in which case you would then wire pin 1 to 1 and pin 3 to pin 2 at the speaker end. Refer to your amps manual.

4. If you run an amp in bridge mono and intend to connect two speakers ( one on each channel of the amp ), then you need to invert the polarity of the speaker connected to the amps second channel to have be in phase again. Remember channel 2 of the amp is inverted when in bridge mono mode.

If you run the amp in bridge mono, you will not need a Y cable, as the input seen on channel one will feed both channels. You could simply chain the channel one through output to the next amp. I would leave the channels center panned to make recording and live audio work more seamlessly.
Title: Re: Bridged amps and stereo playback
Post by: Kevin Graf on October 14, 2016, 07:05:12 AM
Is your wye two outputs into one input or one output into two inputs?
Title: Re: Bridged amps and stereo playback
Post by: Ivan Beaver on October 14, 2016, 07:31:02 AM
Alternatively, you could mix in stereo, then Y-cord your main outputs so the amps see a single input, but you have the option of making stereo board tapes from your alternate output when required.

HTH

Cheers,
Tim
No no no

Do not do this

Due to the loading from the other channel you will get distortion and possibly damage the output of the console

You y to split with no problems but never ever y to combine signals
Title: Re: Bridged amps and stereo playback
Post by: Jamin Lynch on October 14, 2016, 07:59:57 AM
What's the reason for bridging your amps?

What do you hope to accomplish?
Title: Re: Bridged amps and stereo playback
Post by: Steve Loewenthal on October 14, 2016, 08:22:37 AM
Radial makes a direct box that will sum the left + right output from your music device into a single channel. The output from the direct box then goes to your mixer and only uses 1 channel.
Title: Re: Bridged amps and stereo playback
Post by: Andrew Henderson on October 14, 2016, 08:44:54 AM
Also, what about the RCA stereo channels at the end of my board I use for playback music between sets? I have (2) set of RCA channels like that. Can I put Red RCA in red left then pan left, Then put White RCA in next channel red left , then pan left? Would that get my stereo playback at least back to where I can hear the FULL song? You know 1/2 of it missing?
FYI: the white RCA jack is left, red is right.

+1 for Ivan, for NOT summing left and right signals with a regular Y(wye)-cable. Not from your MP3 player and not from your mixer.

Just use 2 channels for the iPod, and one output from the mixer.
Title: Re: Bridged amps and stereo playback
Post by: Tim McCulloch on October 14, 2016, 09:52:22 AM
What's the reason for bridging your amps?

What do you hope to accomplish?

Small amp syndrome?  He's afraid he's not as big as he needs to be? /satire
Title: Re: Bridged amps and stereo playback
Post by: John Roberts {JR} on October 14, 2016, 09:56:11 AM
No no no

Do not do this

Due to the loading from the other channel you will get distortion and possibly damage the output of the console

You y to split with no problems but never ever y to combine signals
True, in general you should not Y outputs together. If both are low impedance you are effectively driving one output into the other. If you hear distortion in that Y output it is caused by current limiting as the two outputs fight each other (one is zigging while the other one zags).

That said this is not a new issue and many manufacturers anticipate customers making such ill advised connections, so incorporate build out impedances (series resistors), Shorting two impedance protected outputs will form a simple voltage divider (in other words it works).

So YMMV. Hard output Y connections are not best practice but will probably work in modern well engineered products.

JR

PS: One could make a very inexpensive Y cable with resistors built in, somebody probably does.
Title: Re: Bridged amps and stereo playback
Post by: Tim McCulloch on October 14, 2016, 09:57:51 AM
Radial makes a direct box that will sum the left + right output from your music device into a single channel. The output from the direct box then goes to your mixer and only uses 1 channel.
The Radial AV-1.  Street price of $100 or so probably puts it out of Jeffrey's budget.

Rapco has a Blox model with 3.5mm trs plug, a level control and XLR-M output.  If Jeffrey has an avalable mic input the Blox unit in much cheaper.  One of the housemen at our downtown Hyatt Regency bought one to play his phone over the ceiling speakers.. >:(
Title: Re: Bridged amps and stereo playback
Post by: Scott Olewiler on October 14, 2016, 10:02:51 AM
What's the reason for bridging your amps?

What do you hope to accomplish?

Correct me if I'm wrong but...

When you bridge an amp, doesn't the the same input produces more output initially, but then you still "max" out at the same level as you would if you were in stereo?  My experiments with subs have shown the same speaker output hitting the limit lights bridged as I got htting them in stereo.
Title: Re: Bridged amps and stereo playback
Post by: Scott Olewiler on October 14, 2016, 10:05:05 AM
The Radial AV-1.  Street price of $100 or so probably puts it out of Jeffrey's budget.

Rapco has a Blox model with 3.5mm trs plug, a level control and XLR-M output.  If Jeffrey has an avalable mic input the Blox unit in much cheaper.  One of the housemen at our downtown Hyatt Regency bought one to play his phone over the ceiling speakers.. >:(

With two RCA to 1/4 adapters the Radial StageBug SB-2 will do it for $70.
Title: Re: Bridged amps and stereo playback
Post by: Jamin Lynch on October 14, 2016, 11:09:38 AM
Correct me if I'm wrong but...

When you bridge an amp, doesn't the the same input produces more output initially, but then you still "max" out at the same level as you would if you were in stereo?  My experiments with subs have shown the same speaker output hitting the limit lights bridged as I got htting them in stereo.

That's kind of what I was eluding to. Is there really a good reason to bridge in the first place?

It would be nice to know what speakers and amps the OP is using.
Title: Re: Bridged amps and stereo playback
Post by: Don Boomer on October 14, 2016, 11:28:41 AM

Also, what about the RCA stereo channels at the end of my board I use for playback music between sets? I have (2) set of RCA channels like that. Can I put Red RCA in red left then pan left, Then put White RCA in next channel red left , then pan left? Would that get my stereo playback at least back to where I can hear the FULL song? You know 1/2 of it missing?

Interesting question. You may not get the FULL song when combining the two sides as there could be a fair amount of cancellation from phase shift. It will depend on the material. For me anyway, if this is just background break music I'd just play one side and be done with it.
Title: Re: Bridged amps and stereo playback
Post by: Mark Wilkinson on October 14, 2016, 12:24:51 PM
Correct me if I'm wrong but...

When you bridge an amp, doesn't the the same input produces more output initially, but then you still "max" out at the same level as you would if you were in stereo?  My experiments with subs have shown the same speaker output hitting the limit lights bridged as I got htting them in stereo.

IME, and going by most all amp specs I've read...there are only two cases I know of where bridging makes sense.... where real power is gained.

.....a single 8 or 4 ohm box will obviously get alot more power bridged than on a single channel.
.... for a couple of 8 ohm boxes wired parallel, bridged produces real power gains vs having each sub on its own single channel.

If you have 4 ohm subs, nothing is to be gained by bridging.  In-series is usually a power wash by the specs , and in-parallel is almost always a 2 ohm no-no

Title: Re: Bridged amps and stereo playback
Post by: Jay Marr on October 14, 2016, 12:48:01 PM
.
.... for a couple of 8 ohm boxes wired parallel, bridged produces real power gains vs having each sub on its own single channel.


I would guess this is the case for the OP.
If he has 2 boxes for tops and subs, they're likely 8ohm boxes and he's getting more power bridging an amp to get max 4ohm output.
Title: Re: Bridged amps and stereo playback
Post by: Art Welter on October 14, 2016, 12:59:26 PM
That's kind of what I was eluding to. Is there really a good reason to bridge in the first place?
Perhaps what is eluding you is in many cases the amp will deliver it's full two channel output to the single load.

As an example of a good reason to use the  bridge mono option, I use one four channel NU4-6000 per side to drive my mains, a bridged pair for the 2x8 ohm lows, one channel for mids, one channel for highs.

If I were to use one channel for each 8 ohm low speaker, each would get only 440 watts peak. The same two channels bridged mono driving a four ohm pair deliver 3000 watts peak, almost 6 dB more "whoopee", a Really Big Deal at 40 Hz, where a 6 dB increase in SPL sounds twice as loud.

Good enough reason for me, and the NU4-6000 run cool with all channels driven to full tilt boogie in the hot summer sun, now turning into the hot fall sun here in sunny (when hurricanes are not wrecking things) Florida.

Art

Title: Re: Bridged amps and stereo playback
Post by: John Roberts {JR} on October 14, 2016, 01:07:48 PM
IME, and going by most all amp specs I've read...there are only two cases I know of where bridging makes sense.... where real power is gained.

.....a single 8 or 4 ohm box will obviously get alot more power bridged than on a single channel.
.... for a couple of 8 ohm boxes wired parallel, bridged produces real power gains vs having each sub on its own single channel.

If you have 4 ohm subs, nothing is to be gained by bridging.  In-series is usually a power wash by the specs , and in-parallel is almost always a 2 ohm no-no
This is an extremely old topic.. maybe perform a search.

JR
Title: Re: Bridged amps and stereo playback
Post by: Tim Halligan on October 14, 2016, 01:27:30 PM
One could make a very inexpensive Y cable with resistors built in, somebody probably does.

Thanks Ivan for pointing out the mistake in my initial post.

I actually did know that...I just neglected to type it in a clearer way.

As to the JR quote...I've actually seen a pre-made Y cable with the appropriate resistors built in...I'm fairly sure it was marketed under the name "Summer Y" or "Summing Y" down here...but it could've just as easily been something cobbled together by one of the local SR companies. It was donkeys' years ago.

Cheers,
Tim
Title: Re: Bridged amps and stereo playback
Post by: Jamin Lynch on October 14, 2016, 01:28:35 PM
Perhaps what is eluding you is in many cases the amp will deliver it's full two channel output to the single load.

As an example of a good reason to use the  bridge mono option, I use one four channel NU4-6000 per side to drive my mains, a bridged pair for the 2x8 ohm lows, one channel for mids, one channel for highs.

If I were to use one channel for each 8 ohm low speaker, each would get only 440 watts peak. The same two channels bridged mono driving a four ohm pair deliver 3000 watts peak, almost 6 dB more "whoopee", a Really Big Deal at 40 Hz, where a 6 dB increase in SPL sounds twice as loud.

Good enough reason for me, and the NU4-6000 run cool with all channels driven to full tilt boogie in the hot summer sun, now turning into the hot fall sun here in sunny (when hurricanes are not wrecking things) Florida.

Art

Something wasn't "eluding me" ....I was "eluding to" something.
Title: Re: Bridged amps and stereo playback
Post by: Art Welter on October 14, 2016, 01:53:19 PM
For me anyway, if this is just background break music I'd just play one side and be done with it.
Don,

There are countless songs mixed with hard-panned tracks, if you don't properly combine left/right, you get a random lack of something or other.

While reading your reply, was listening to Jimi Hendrix' "If 6 were 9".
The main vocals are only in the right channel, guitar left.
Which channel do you choose to omit, vocals, or guitar?

Right is wrong, but Hendrix played right hand guitars left handed...

Art

Title: Re: Bridged amps and stereo playback
Post by: Tom Roche on October 14, 2016, 03:14:41 PM
Something wasn't "eluding me" ....I was "eluding to" something.

Elude vs. allude

Art made two points in short order.  It's all good.  :)
Title: Re: Bridged amps and stereo playback
Post by: Jerome Malsack on October 14, 2016, 03:31:16 PM
http://forums.prosoundweb.com/index.php/topic,161058.0.html

Jeff has two JBL speakers and the amp is an Itech 2000. 
Title: Re: Bridged amps and stereo playback
Post by: Jeffrey l jones on October 14, 2016, 03:47:19 PM
http://forums.prosoundweb.com/index.php/topic,161058.0.html

Jeff has two JBL speakers and the amp is an Itech 2000.

XTI2000 & XTI 4000
JBL SR4735X
Yamaha SW118V
Just fell the JBL's need more than 650watt apiece
The XTI's have built in limiters.
Title: Re: Bridged amps and stereo playback
Post by: Jamin Lynch on October 14, 2016, 04:08:26 PM
Elude vs. allude

Art made two points in short order.  It's all good.  :)

Dat dern spel sheker.  :o Gotta blame it on something
Title: Re: Bridged amps and stereo playback
Post by: Mark Wilkinson on October 14, 2016, 04:39:36 PM
This is an extremely old topic.. maybe perform a search.

JR

John,  are you suggesting that we shouldn't try to help on old topics?

If that's not your suggestion, why quote me ?  :)
Title: Re: Bridged amps and stereo playback
Post by: John Roberts {JR} on October 14, 2016, 05:31:13 PM
John,  are you suggesting that we shouldn't try to help on old topics?

If that's not your suggestion, why quote me ?  :)
I believe I wanted to make the point that this is a very old topic that has been explained at length numerous times.

You just happened to be the vehicle for me to make that point, I like to quote so my comments make sense in context.

Sorry if you feel singled out, I assure you I mean nothing other than what I said. This is a very old topic that has been well explored.

I even played along for a while.

Carry on without me... this time.

JR
Title: Re: Bridged amps and stereo playback
Post by: Tim McCulloch on October 14, 2016, 06:23:25 PM
http://forums.prosoundweb.com/index.php/topic,161058.0.html

Jeff has two JBL speakers and the amp is an Itech 2000.

No such thing as an Itech 2000.  XTi, CE, maybe some ComTech, but not ITech.

Edit PS. Beaten to the punch.
Title: Re: Bridged amps and stereo playback
Post by: Luke Geis on October 14, 2016, 06:39:37 PM
There is an old trick in which running an amp in bridge mono mode and simply connecting two speakers to each channel ( with channel two's connections reversed ) would net you a gain of about 15% more power. The downside is that you won't have stereo. This is great if you are splaying speakers together or have a line array. The debate is on whether this is a practical and viable option?

The problem is the need to invert the connection on one half of the amp which adds to confusion. The second is that even if 15% more power is gained, is it really worth it? I prefer to go with the K.I.S.S theory and simply keep it simple. 15% more of 1000 watts is only 150 watts. Since you need double the wattage to net a 3db increase in SPL, 150 watts is going to get you pretty much nowhere. It won't even get you a full db more in SPL, which means no appreciable gain for the extra work involved.

Pretty much the only time you should desire to bridge mono an amp is if you need to drive that much power into several speakers that will work within the amps minimum ohm rating, or you simply can't afford to acquire an amp big enough to power what you currently have in the conventional way. Subs are a prime example of speakers that are often powered by a bridge mono amp. Many subs these days are rated for a peak rating of between 3000 to 6000 watts! Not too many amps will deliver even 3000 watts per channel at 4 ohm's. So the only way to get ample power and save money is to use an amp with a bridge mono rating that will get you the wattage you need.
Title: Re: Bridged amps and stereo playback
Post by: Tim McCulloch on October 14, 2016, 06:54:24 PM
There is an old trick in which running an amp in bridge mono mode and simply connecting two speakers to each channel ( with channel two's connections reversed ) would net you a gain of about 15% more power. The downside is that you won't have stereo. This is great if you are splaying speakers together or have a line array. The debate is on whether this is a practical and viable option?

The problem is the need to invert the connection on one half of the amp which adds to confusion. The second is that even if 15% more power is gained, is it really worth it? I prefer to go with the K.I.S.S theory and simply keep it simple. 15% more of 1000 watts is only 150 watts. Since you need double the wattage to net a 3db increase in SPL, 150 watts is going to get you pretty much nowhere. It won't even get you a full db more in SPL, which means no appreciable gain for the extra work involved.

Pretty much the only time you should desire to bridge mono an amp is if you need to drive that much power into several speakers that will work within the amps minimum ohm rating, or you simply can't afford to acquire an amp big enough to power what you currently have in the conventional way. Subs are a prime example of speakers that are often powered by a bridge mono amp. Many subs these days are rated for a peak rating of between 3000 to 6000 watts! Not too many amps will deliver even 3000 watts per channel at 4 ohm's. So the only way to get ample power and save money is to use an amp with a bridge mono rating that will get you the wattage you need.

Running a loudspeaker at the "rated" power for more than brief instances will ultimately result in the destruction of that loudspeaker.  You might as well use an amp 1/4 the size and let it clip - and frankly that's what we did 20 years ago with the "big" Crest 8001 - 750W @8 Ohms.

Especially on bass-reflex subwoofer designs any distortion from clipping was masked by the substantial harmonic distortion of the subwoofer itself.

The programme material and ability of a loudspeaker to dissipate heat have far more to do with the selection of amplifier power than mere published specifications.
Title: Re: Bridged amps and stereo playback
Post by: Luke Geis on October 15, 2016, 02:43:27 PM
Running a loudspeaker at the "rated" power for more than brief instances will ultimately result in the destruction of that loudspeaker.  You might as well use an amp 1/4 the size and let it clip - and frankly that's what we did 20 years ago with the "big" Crest 8001 - 750W @8 Ohms.

Especially on bass-reflex subwoofer designs any distortion from clipping was masked by the substantial harmonic distortion of the subwoofer itself.

The programme material and ability of a loudspeaker to dissipate heat have far more to do with the selection of amplifier power than mere published specifications.

While I was slightly vague about what wattage you NEED, that topic is well documented at this point of course. The point of the comment being that the average guy can't afford Powersoft K10 or K20 amps to power their subs rated for 6,000 + watts peak in two channel stereo mode. Granted , NO you DO NOT need to power a sub with its peak rated wattage, but affordable options are few and often bridging an amp is required to get the needed wattage.

For example: You get yourself a nice, pretty, new JBL STX dual 18" passive sub. It has a peak wattage rating of 8,000 watts! Ideally, you want to power it with about 4,000 watts, but can go as much as 6,000 watts if you want to go for all out performance. Depending upon needs and application you may even desire to power it with an amp that produces around 2,000 watts? Either way you have a few different ways of powering it and each has it's pro's and cons.

There are plenty of amps that you can buy that will provide 2,000 watts in dual channel operation. There ARE NOT as many affordable amps that will provide 4,000 watts in dual channel operation. So you are left with two choices. You can either pony up to get the Lab Gruppen, Powersoft and upper end Crown offerings, which will cost more than the speaker you're powering them with, or you can buy lower end products and run them in bridge mono mode to get the needed wattage?

I believe that powering a speaker with at least its program rating is the best all around option, certainly NEVER use an amp rated for the same peak wattage as the speaker it is powering. Subs these days are power hungry and the average peak wattage is sitting around the 6,000 watt range. This means that most will need an amp that will produce around the 3,000 watt per channel at 4 ohm mark. There are not too many options that will do that. There are lots that will produce that wattage cheaply in bridge mono mode though.

Most are not fans of running amps in bridge mono mode however. It increases potential distortion, reduces the damping factor and makes the amp work harder, lessening its life. At the cost of making more power, it sacrifices quality and itself to do so. Another downside is that you will need multiples to power multiples of anything. So if you have 4 subs, you will need 4 amps. It is possible that buying 2 higher end power house amps is cheaper than buying 4 smaller amps? If you need several amps the weight and space consumption goes up. If you can buy 2 amps that do the job of 4 and have similar investment cost, you can see the obvious gains in doing so. I am not a fan of running in bridge mono myself, but when you don't have another option and you have to run what you have, you do what needs to be done.

Title: Re: Bridged amps and stereo playback
Post by: Tim McCulloch on October 15, 2016, 04:57:55 PM
Luke, my point is that one does not need 3000 or 6000 Watts and that for most uses, doing so puts one into the territory of diminishing returns.
Title: Re: Bridged amps and stereo playback
Post by: Ivan Beaver on October 15, 2016, 06:31:20 PM
There is an old trick in which running an amp in bridge mono mode and simply connecting two speakers to each channel ( with channel two's connections reversed ) would net you a gain of about 15% more power.
Not necessarily.  It depends GREATLY on the power supply of the amplifier.

If the amp has common power supply, then you can get a slight increase in power-less than 1 dB.

If the amp has dual power supplies, (the channels don't share a common supply), then there in no increase in power.

It also depends on the type of power supply.  Is it an old transformer/bridge/cap power supply or a switching supply that operates at a high freq?

It all has to do with how fast the power supply can recharge.

There "might" be a increase in power that is not noticeable by anybody, or no increase at all.

The possibility of getting quite a bit LESS sound (by wiring it incorrectly) is MUCH higher, and in my opinion, not worth the effort.

Title: Re: Bridged amps and stereo playback
Post by: Don Boomer on October 15, 2016, 06:56:07 PM
Don,

There are countless songs mixed with hard-panned tracks, if you don't properly combine left/right, you get a random lack of something or other.

While reading your reply, was listening to Jimi Hendrix' "If 6 were 9".
The main vocals are only in the right channel, guitar left.
Which channel do you choose to omit, vocals, or guitar?


Right is wrong, but Hendrix played right hand guitars left handed...

Art

Agreed. It depends on the material and how important or non important the background music is. But you'd also need to watch if you played Jimi in stereo and a listener was near one stack or the other where they would also only hear one side. ;)
Title: Re: Bridged amps and stereo playback
Post by: Don Boomer on October 15, 2016, 07:05:25 PM
Running a loudspeaker at the "rated" power for more than brief instances will ultimately result in the destruction of that loudspeaker. 

My experience says otherwise. First, you are likely to never run full rated continuous power to a speaker using "program" rated amps. In fact it's not likely that you'd even ever deliver half power continuously. Furthermore both AES and EIA power tests run full power for 2 hours and 8 hours respectively without speaker damage.

I remember running tests where we ran speakers with amps 5x the rated power (500w AES rated speakers with 2500w power amp) into clipping (limiters bypassed) for a few hours (until we got shutdown by the cops).  We took the speakers back into the shop and broke them down. There was no damage to those.

We DID use proper high pass filters however.
Title: Re: Bridged amps and stereo playback
Post by: John Roberts {JR} on October 15, 2016, 07:21:26 PM
There is an old trick in which running an amp in bridge mono mode and simply connecting two speakers to each channel ( with channel two's connections reversed ) would net you a gain of about 15% more power. The downside is that you won't have stereo. This is great if you are splaying speakers together or have a line array. The debate is on whether this is a practical and viable option?




Google Dave Rat trick, or Dave Rat article.

How much louder do you think 15% is?

JR 

PS: Can we just number these? That old #29 coming through again.
Title: Re: Bridged amps and stereo playback
Post by: Ivan Beaver on October 15, 2016, 08:51:41 PM


PS: Can we just number these? That old #29 coming through again.
:) :) :) :) :)

Didn't we talk about #3 last week????????  ;) ;)