Balanced Amp Vs UnBalanced

[greggp2]

I currently have an Emo XPA-2 Amp and am looking to purchase either an XPA-5 or a UPA-7 Amp from Emotiva.

The XPA-5 has a little more power, but I am only using this for my Center and Rears and maybe other zones in the house. The XPA-5 will do the job, but it's almost $300 more with the sale Emotiva currently has. It has a little more power, but honestly, I'm a little concerned about sending too much power to my rears during intense surround scenes. My rear speakers are rated at 130 Watts and with the XPA-5, I'll only be driving 3 speakers most of the time, so the max power being sent to the rears will be 250 watts.

The other main difference, other than power is the balanced vs unbalanced connections. The processor I will upgrade to next, the Anthem D2v or AVM50v has balanced connections. Does it really make that big of a difference in noise reduction in the home?

I guess the question is, is it worth it to spend almost $300 more on the XPA-5 for the balanced connections, and if I do that, will I be risking blowing my rear speakers at high volume levels during movies or possibly when listening to music in all channel stereo during parties?

 

[walter duque]

I don't think you need to worry about blowing your rear speakers. You can always adjust your Pre/Pro just keep the db's down. I have my center bi-amped which is rated at 220 Watts and I run 350WattsX2 and have never blown a speaker. Besides I like to run my system at 115-120db and no problem.

 

[MidnightSensi]

I guess the question is, is it worth it to spend almost $300 more on the XPA-5 for the balanced connections, and if I do that, will I be risking blowing my rear speakers at high volume levels during movies or possibly when listening to music in all channel stereo during parties?

Balanced connections are nice, but they don't make much of a difference in a home environment. If you have a noise floor you can hear, your noise level will go to basically nothing. But when I had my unbalanced gear I never had noise problems either, so, *shrug* However, Audioholics did mention in their review of one of the Emotivas that they have unusually high voltage gain, so maybe it would be benefitial for you to get the balanced connections.


You an adjust the levels of your rear speakers for when running all channel stereo, but I wouldn't worry about more power blowing them, actually underpowering them and driving your preamplifier or amplifier into clipping is more dangerous. You'll hear when the speaker is straining or going to die, just go easy on the volume knob when it starts to sound strained. I'm not sure if Emotiva has any speaker protection circuitry, or a built in limiter, but, that might be something to ask them about.


If you go the seperates route, its important to setup your gain structure well. Basically, you want your preamplifier to clip at the same point as your amplifier. We can help you set this up once your gear comes in.

 

[Swerd]

… The other main difference, other than power is the balanced vs unbalanced connections. The processor I will upgrade to next, the Anthem D2v or AVM50v has balanced connections. Does it really make that big of a difference in noise reduction in the home?

I guess the question is, is it worth it to spend almost $300 more on the XPA-5 for the balanced connections, and if I do that, will I be risking blowing my rear speakers at high volume levels during movies or possibly when listening to music in all channel stereo during parties?

I don't think paying $300 more just to get balanced connections for home use is worth it. Balanced connections are needed for microphones because their signal levels are very low, and long cables can pick up noise from relatively low levels of electromagnetic interference (EMI). In recording studios, where there can be a lot of sources of EMI, and where there are a lot of long mic cables lying around, its easier to use balanced cables than to try to track down and eliminate the EMI.

In a home system, the line level signal from a preamp to an amp is stronger than from a microphone, so it is less sensitive to EMI. And you will probably be using short interconnects (3 feet instead of 30 feet) between the preamp and amp. For home use, standard unbalanced interconnects with RCA plugs are fine.

 

[AcuDefTechGuy]

No such thing as too much power!

I would get the XPA-5.

 

[greggp2]

Guys, thanks for all the feedback so far.

Does anyone know, looking at the specs between these two pieces (UPA-7 vs XPA-5), if one is superior to the other? Aside from the obvious balanced connection option and additional power with the XPA-5, are there any other advantages in terms of quality of components used, build quality, etc?

 

[Warpdrv]

Hey gregg, every time I see this question, It always brings me back a post that EJ from Wyred4Sound made... I found it more informative then most answers you will get. This is the reason I am going balanced. Hope that helps.

I'd rather quote him, and not pawn it off as my own...

Even though the amplifier will be driven balanced on a single-ended source, there are many advantages to using balanced (XLR). This would mainly be beneficial if you can connect from the beginning with XLR all the way to the amplifier.

An RCA connector consists of a + signal, and ground (shield). An XLR connector consists of a + signal, - signal, and ground (shield).

When using RCA, the ground (shield) is connected to the – signal input on the amplifier. If you have any noise or interference in your system, it will be amplified through the amp, and out your speakers. The amplifier then derives the – signal from the + signal by inverting it 180deg out of phase with respect to the + input.

When using XLR the + and – signals are a product of the source, and the ground is simply a shield. The major advantage is that the ground or shield isn’t tied in with any of the signals. Not to mention that neither of the signals are “made up”, or referenced to ground.

All in all, we have found that XLR connections have a much better sonics than RCA. The most noticable would be that the noise level is reduced. Some of the cheapest XLR cables, can be much better than some of the expensive RCA's, so that would be something to consider. However, if you have a REALLY quiet system (noise), you wouldn't see much improvement.

 

[greggp2]

Warp,

some interesting info... I just spoke with someone that has an AVM50. He was telling me that he spoke with one of the engineer at Athem and that their processors are not truely balanced... He said that when you make a balanced connection, the processor is actually converting it to unbalanced and then back to balanced again. so in essence the conversion is happening 2x as opposed to 1. Does this make any sense? If this the case, why would anyone want an extra conversion in the process?

Confused...

Hey gregg, every time I see this question, It always brings me back a post that EJ from Wyred4Sound made... I found it more informative then most answers you will get. This is the reason I am going balanced. Hope that helps.

I'd rather quote him, and not pawn it off as my own...

 

[GlocksRock]

So the short answer is it may make a difference, but most likely you are better off just sticking with rca's unless you have a lot of noise in your system.

 

[darien87]

Guys, thanks for all the feedback so far.

Does anyone know, looking at the specs between these two pieces (UPA-7 vs XPA-5), if one is superior to the other? Aside from the obvious balanced connection option and additional power with the XPA-5, are there any other advantages in terms of quality of components used, build quality, etc?

There's not much difference between them at all. The XPA series amps are actually based on the LPA design, as is the UPA-7. There are slight differences between them, but the only REAL difference is the number of channels and power.

 

[greggp2]

I just got off the phone with Emotiva and they pretty much told me the same thing. Not much difference other than connections, power and channels.

I spoke to them about the UMC-1 and I really am tempted on waiting a few more months for it. The also mentioned an XMC which will be an upgraded version to the UMC with Video output to other zones, balanced connections and some other small upgrades.

For the money, the UMC-1 sounds like it is going to be a very impressive unit... It should be in by summer, so, I may wait. It also is going to contain some type of room correction that is supposed to be more than just the typical speaker setup, etc...

 

[darien87]

I just got off the phone with Emotiva and they pretty much told me the same thing. Not much difference other than connections, power and channels.

I spoke to them about the UMC-1 and I really am tempted on waiting a few more months for it. The also mentioned an XMC which will be an upgraded version to the UMC with Video output to other zones, balanced connections and some other small upgrades.

For the money, the UMC-1 sounds like it is going to be a very impressive unit... It should be in by summer, so, I may wait. It also is going to contain some type of room correction that is supposed to be more than just the typical speaker setup, etc...

I've been on the pre-order list for the UMC since it was announced. The wait has been a little trying, but I'm sure it will be worth it, and I have my 661 to do uncompressed audio in the meanwhile.

 

[greggp2]

I've been on the pre-order list for the UMC since it was announced. The wait has been a little trying, but I'm sure it will be worth it, and I have my 661 to do uncompressed audio in the meanwhile.

I'm sure you'll get one way before people like me, if I opt the route to wait. Be sure to let us know your impressions...

I still have difficulty believing their Amps and products compete with products selling for 3-4 times their price, but so far, their XPA-2 has been quite impressive...

They probably aren't in the same league, but I'm considering holding out for the UMC-1 as opposed to getting an Anthem D2v, AVM50 or the Cary Cinema 11a...

 

[Warpdrv]

Warp,

some interesting info... I just spoke with someone that has an AVM50. He was telling me that he spoke with one of the engineer at Athem and that their processors are not truely balanced... He said that when you make a balanced connection, the processor is actually converting it to unbalanced and then back to balanced again. so in essence the conversion is happening 2x as opposed to 1. Does this make any sense? If this the case, why would anyone want an extra conversion in the process?

Confused...

I asked, and this has been asked in the Anthem thread a few times, and this is the answer that comes back.
I honestly don't know what is the right answer..... One thing I do know, is my amp is full balanced, and the ground will then be connected through the XLR, through to the D2v, and the + and - are separate lines through.

From the Anthem Q&A site... http://statement.anthemav.com/HTML/TechnicalSupport/TechSupport.html#Q1

Q1: Are the XLR connections on the amps and preamps truly balanced?

A: Yes. All three pins of the XLR connection are part of the circuit, which means it's a real balanced connection. (If pin 3 is sent to ground or left open, as is sometimes the case, then an XLR jack is an adapter, not a balanced input.) The purpose of balanced connection is cancelling out certain types of interference and ground loops.


Q2: What about the whole circuit from front to back - is it fully balanced?

A: No. At some point the signal must become single-ended, or interference can't be cancelled. This is better done sooner rather than later in the signal chain. The purpose of a balanced stage within a circuit is cancelling out nonlinearities arising in the circuit itself, and/or to double the signal level while cancelling out some noise. This is purely a means, not an end. We use a balanced arrangement in specific areas within a circuit where it makes a meaningful difference. Doing this to an entire piece of equipment for the sake of using the catch phrase "fully balanced" may achieve nothing but a significant increase in cost, or worse if the two halves of the circuit aren't matched well.