XPA-5 crosstalk

[niceguyedy]

I recently discovered that when I was listening to music in stereo mode, that my center channel drivers were moving along with the music. To attempt to isolate the issue, I unhooked the RCA going to my center channel section of the amp. The drivers were still moving. When I unhooked the speaker wire, the drivers stopped moving. So, there is crosstalk, and it's in the amp.

I e-mail tech support, and they had me run a couple more tests, then told me that the cross talk was normal. Now, I understand you can't fully isolate 5 channels, but why isn't anyone else noticing this? Even at -20 on my avr the drivers are moving.

I know my options are to either buy mono blocks, or perhaps an XPA-2 for just the front left and right, and leave the xpa 5 for surround and center duties.

Has anyone else noticed crosstalk? Have you looked for it? Please let me know what you find. I would appreciate it.

[Topend]

Nov 24, 2010 22:50:17 GMT -5 niceguyedy said:

I recently discovered that when I was listening to music in stereo mode, that my center channel drivers were moving along with the music. To attempt to isolate the issue, I unhooked the RCA going to my center channel section of the amp. The drivers were still moving. When I unhooked the speaker wire, the drivers stopped moving. So, there is crosstalk, and it's in the amp.

I e-mail tech support, and they had me run a couple more tests, then told me that the cross talk was normal. Now, I understand you can't fully isolate 5 channels, but why isn't anyone else noticing this? Even at -20 on my avr the drivers are moving.

I know my options are to either buy mono blocks, or perhaps an XPA-2 for just the front left and right, and leave the xpa 5 for surround and center duties.

Has anyone else noticed crosstalk? Have you looked for it? Please let me know what you find. I would appreciate it.

Doesn't sound right to me. I have never experienced this with my XPA-5.

Dave.

[ntrain42]

Nov 24, 2010 22:50:17 GMT -5 niceguyedy said:

I recently discovered that when I was listening to music in stereo mode, that my center channel drivers were moving along with the music. To attempt to isolate the issue, I unhooked the RCA going to my center channel section of the amp. The drivers were still moving. When I unhooked the speaker wire, the drivers stopped moving. So, there is crosstalk, and it's in the amp.

I e-mail tech support, and they had me run a couple more tests, then told me that the cross talk was normal. Now, I understand you can't fully isolate 5 channels, but why isn't anyone else noticing this? Even at -20 on my avr the drivers are moving.

I know my options are to either buy mono blocks, or perhaps an XPA-2 for just the front left and right, and leave the xpa 5 for surround and center duties.

Has anyone else noticed crosstalk? Have you looked for it? Please let me know what you find. I would appreciate it.

Yep, I found that all Emotiva multichannel amps have crosstalk. Thats their one big weakness/downfall. I took alot of cr@p from some members for noticing this myself and complaining about it. Its why I only use or recommend UPA-5/7 XPA-2/3/5 for HT use. For serious music audiophiles, I only recommend the UPA-1, XPA-1 and in the rare case an XPA-2 that is bridged mono into a monoblock arrangement.

[niceguyedy]

I will admit, I was not happy to hear that this is considered "minimal" and "normal". The XPA-1's are too much power for my speakers, and I don't really want to buy 3 UPA 1's. I honestly feel like i'm kind of painted into a corner here.

[Deleted]

no crosstalk on mine when listening to stereo mode...seems very odd.

[niceguyedy]

Nov 25, 2010 0:05:55 GMT -5 neekos said:

no crosstalk on mine when listening to stereo mode...seems very odd.

How loud were you? I was at -20 on my Pioneer and was still noticing. Perhaps this is how the amp gives great imaging, by having power go to the center channel too. lol

[roadrunner]

A fact of life is that all multichannel amps suffer from crosstalk, not just those from Emotiva. The question is whether the problem is audible. Niceguy, did you hear the music coming from the center channel, or did you just notice the cone was moving? The movement your witnessed can be caused by other things, so that alone does not necessarily mean you have a crosstalk problem with the amp. Running unshielded speaker wire can also produce sympathetic movement in the drivers of adjacent speaker wires. Sometimes this interference is even audible.

You can take steps to minimize the impact if this type of interference does become audible. Just curious, what types of tests did Emotiva have you do to check for crosstalk; and did any of those tests reveal whether the problem was serious enough to be audible or more audible? Did the support tech offer any ways you can minimize audible feedback? As you know, the only way to totally avoid crosstalk is to use Mono-block amps. As with everything in life there will always be trade offs in the decisions we make. I wish it wasn't so, but you can't have you cake and eat it too. ;D

[sharkman]

Nov 24, 2010 23:11:19 GMT -5 ntrain42 said:

Yep, I found that all Emotiva multichannel amps have crosstalk. Thats their one big weakness/downfall. I took alot of cr@p from some members for noticing this myself and complaining about it. Its why I only use or recommend UPA-5/7 XPA-2/3/5 for HT use. For serious music audiophiles, I only recommend the UPA-1, XPA-1 and in the rare case an XPA-2 that is bridged mono into a monoblock arrangement.

I remember reading about your issue, but wasn't it with a UPA multi channel amp? At any rate, I wouldn't lump the XPA-2 in with the rest, audioholics tested it and found it to measure at 140db for crosstalk. Here's the data:

Crosstalk

Running a full range frequency sweep through the XPA-2 amplifier at full rated power (250wpc @ 8-ohms), I measured channel to channel crosstalk between the two channels where one was the disturber and the other was the Device Under Test (DUT). The Audio Precision plotted crosstalk of both channels over frequency by varying the Distruber/DUT channels. The XPA-2 produced surprisingly excellent crosstalk measurements (>140dB at 1kHz) with only a gradual rise with increasing frequency because of capacitive coupling. This is the best crosstalk measurement I’ve ever measured in an amplifier and despite the XPA-2 having a singular centralized power supply, the channel to channel isolation was on par with the best monoblock amplifiers I’ve ever seen!

But what the OP is experiencing sounds like more than a crosstalk issue.

[hemster]

I can't detect any crosstalk at low, medium or high volumes in my rig. I've placed my ear right up to the speakers but nothing... I am very happy with mine for both HT and music usage.. but then, I really would like the purist approach of running monoblocks... as soon as I win that lotto.

To the OP, if you haven't already, I'd suggest you call Emotiva to see how they can help with this issue.

[NorthStar]

This is very strange!

Edy, can you tell me what Stereo recording you were listening to?
- And how far is your Center speaker from your two front mains?
- And did you have your subwoofer playing also? How far is it from your Center speaker?
- And finally, the speaker cable for your center speaker, where does it run close to?

- Your Pioneer Elite VSX-03TXH receiver, did you check what audio mode it was on, and also did you check with its own internal amps? If not, please do so!
* Did you know that any type of radio, channel station from the tuner inside your receiver can bleed into your speakers? Even if the source is not the Tuner? That's right mister. It's a fact!
=> SOLUTION: Select a DEAD station from your Tuner.

* I shall find the cause of this.

[niceguyedy]

Nov 25, 2010 0:44:37 GMT -5 roadrunner said:

A fact of life is that all multichannel amps suffer from crosstalk, not just those from Emotiva. The question is whether the problem is audible. Niceguy, did you hear the music coming from the center channel, or did you just notice the cone was moving? The movement your witnessed can be caused by other things, so that alone does not necessarily mean you have a crosstalk problem with the amp. Running unshielded speaker wire can also produce sympathetic movement in the drivers of adjacent speaker wires. Sometimes this interference is even audible.

You can take steps to minimize the impact if this type of interference does become audible. Just curious, what types of tests did Emotiva have you do to check for crosstalk; and did any of those tests reveal whether the problem was serious enough to be audible or more audible? Did the support tech offer any ways you can minimize audible feedback? As you know, the only way to totally avoid crosstalk is to use Mono-block amps. As with everything in life there will always be trade offs in the decisions we make. I wish it wasn't so, but you can't have you cake and eat it too. ;D

Hello Justin,

Thank you for being an Emotiva customer. There is a slight amount of crosstalk on the XPA-5 but it is extremely low. Now depending on how efficient your speakers are, even the slightest amount of noise can be audible. If you rearrange your connections on the amplifier do you still hear the crosstalk or is it only on the center channel? Let me know what you are able to find.

Best Regards,



Emotiva Support

Hello Justin,

This tells me that the crosstalk you are experiencing is normal. You have 5 high current modules running side by side in a confined space. There is going to be oscillation between modules and it will give you some crosstalk. We minimize it as much as possible but there is no way to completely get rid of it. If you want an amplifier that has absolutely no crosstalk, a mono block is the only way to go. Two UPA-1s would isolate the channels and would solve your dilemma completely. I hope this helps.

Best Regards,



Emotiva Support

Those are the responses from Emotiva.

[niceguyedy]

Nov 25, 2010 2:20:40 GMT -5 NorthStar said:

This is very strange!

Edy, can you tell me what Stereo recording you were listening to?
- And how far is your Center speaker from your two front mains?
- And did you have your subwoofer playing also? How far is it from your Center speaker?
- And finally, the speaker cable for your center speaker, where does it run close to?

- Your Pioneer Elite VSX-03TXH receiver, did you check what audio mode it was on, and also did you check with its own internal amps? If not, please do so!
* Did you know that any type of radio, channel station from the tuner inside your receiver can bleed into your speakers? Even if the source is not the Tuner? That's right mister. It's a fact!
=> SOLUTION: Select a DEAD station from your Tuner.

* I shall find the cause of this.

I have a narrow room, the center is about 2.5ft from each main.
The sub was playing and it is 13ft from the center.
The speaker cable runs along the floor. I know that it runs with the other speaker wire.

I have NEVER used the internal amps of my receiver. This issue was localized to the xpa 5. When the rca was unplugged from the receiver for the center channel, there was still cross talk.

The music I was listening to, and it does it for everything, was from my computer. It also does it when streaming through my xbox, and my ps3.

I think the fact remains that if other people have no issues with it, and I do, there is a problem with the amp. However, Emotiva have already stated that this is normal. However, I don't agree or approve.

The last things I'm going to check are, unhooking the right and left mains from the amp, turning the music up, and see if the center channel is still getting cross talk. If it is, it HAS to be in the amp, and cannot be getting a signal caused by wires too close, or by electrical outlets.

[Legis]

Cone's movement ain't telling much. I think the channel separation could be tested by silencing your front speakers by disconnecting the other (+ or -) speaker wire and then listen to the center channel alone (with front speakers' feed). There should be some interchannel leakage, but I think you can tell when the leakage is too strong. After this, connect the center channel's speaker wires to XPA-5's output no. 4 and 5 and see if the leakage is similar.

[NorthStar]

2.5 feet is very close, so the sound of your other fronting speakers can easily move the cones in your center speaker.

[ntrain42]

Nov 25, 2010 0:44:37 GMT -5 roadrunner said:

A fact of life is that all multichannel amps suffer from crosstalk, not just those from Emotiva. The question is whether the problem is audible. Niceguy, did you hear the music coming from the center channel, or did you just notice the cone was moving? The movement your witnessed can be caused by other things, so that alone does not necessarily mean you have a crosstalk problem with the amp. Running unshielded speaker wire can also produce sympathetic movement in the drivers of adjacent speaker wires. Sometimes this interference is even audible.

You can take steps to minimize the impact if this type of interference does become audible. Just curious, what types of tests did Emotiva have you do to check for crosstalk; and did any of those tests reveal whether the problem was serious enough to be audible or more audible? Did the support tech offer any ways you can minimize audible feedback? As you know, the only way to totally avoid crosstalk is to use Mono-block amps. As with everything in life there will always be trade offs in the decisions we make. I wish it wasn't so, but you can't have you cake and eat it too. ;D

This is true, but the question is: How Audible is it? On my Onkyo 906 reciever it isnt audible at all. Denon recievers are very good at suppressing crosstalk as well. Neither was it audible on older Rotel or Aragon multichannel amplifiers.

The truth is, some multichannel amps are very good at suppressing crosstalk. Others aren't. If there is one big weakpoint with Emotiva amps its their crosstalk suppresion. Its very poor IMO.

[ntrain42]

Nov 25, 2010 1:30:39 GMT -5 sharkman said:

Nov 24, 2010 23:11:19 GMT -5 ntrain42 said:

Yep, I found that all Emotiva multichannel amps have crosstalk. Thats their one big weakness/downfall. I took alot of cr@p from some members for noticing this myself and complaining about it. Its why I only use or recommend UPA-5/7 XPA-2/3/5 for HT use. For serious music audiophiles, I only recommend the UPA-1, XPA-1 and in the rare case an XPA-2 that is bridged mono into a monoblock arrangement.

I remember reading about your issue, but wasn't it with a UPA multi channel amp? At any rate, I wouldn't lump the XPA-2 in with the rest, audioholics tested it and found it to measure at 140db for crosstalk. Here's the data:

Crosstalk

Running a full range frequency sweep through the XPA-2 amplifier at full rated power (250wpc @ 8-ohms), I measured channel to channel crosstalk between the two channels where one was the disturber and the other was the Device Under Test (DUT). The Audio Precision plotted crosstalk of both channels over frequency by varying the Distruber/DUT channels. The XPA-2 produced surprisingly excellent crosstalk measurements (>140dB at 1kHz) with only a gradual rise with increasing frequency because of capacitive coupling. This is the best crosstalk measurement I’ve ever measured in an amplifier and despite the XPA-2 having a singular centralized power supply, the channel to channel isolation was on par with the best monoblock amplifiers I’ve ever seen!

But what the OP is experiencing sounds like more than a crosstalk issue.

Problem is, they measured crosstalk with a narrowband 1khz test tone, not a full range music signal which can be easier to detect and pick up with sensitive ears. Because it sure ain't anywhere near 140db with a full music signal. Regardless, the XPA-2 has some crosstalk as well, but its within an acceptable limit, and its nowhere near as bad as the XPA-3/5 and UPA-5/7.

[Porscheguy]

I have an XPA-5 and I have experienced no cross talk. Zero, zip, zilch, nata...... I had a UPA-7 for a month or so and no issues with it either. It seems that a very few amps have this phenomenon. One of the mags tested the XPA-5 for crosstalk and it was so far below the noise floor - it was completely inaudible. For a while I was using two of my XPA-5 channels to run other speakers in another room and no matter how loud the volume, I never anything through my center channel or surrounds downstairs - not a peep, ever........

If you have drivers moving on other channels that sound to me like a defect. That goes way past "cross talk"...

[Animo]

Nov 25, 2010 3:36:09 GMT -5 niceguyedy said:

I have a narrow room, the center is about 2.5ft from each main.
The sub was playing and it is 13ft from the center.
The speaker cable runs along the floor. I know that it runs with the other speaker wire.

I have NEVER used the internal amps of my receiver. This issue was localized to the xpa 5. When the rca was unplugged from the receiver for the center channel, there was still cross talk.

The music I was listening to, and it does it for everything, was from my computer. It also does it when streaming through my xbox, and my ps3.

I think the fact remains that if other people have no issues with it, and I do, there is a problem with the amp. However, Emotiva have already stated that this is normal. However, I don't agree or approve.

The last things I'm going to check are, unhooking the right and left mains from the amp, turning the music up, and see if the center channel is still getting cross talk. If it is, it HAS to be in the amp, and cannot be getting a signal caused by wires too close, or by electrical outlets.

I have not witnessed any problems with my XPA-5 that you are describing. I see you mentioned the sub was playing.......blame it all on that monster ;D

[Mischief]

Many never notice crosstalk because under normal use only very efficient speakers will reveal it but there are always exceptions. I have found that the processors and/or analog outputs in many AVR also cause this issue by sending soft audio through unused speakers. I have seen this with full monoblock systems so it isn't always amp related.

[ocezam]

Nov 25, 2010 8:31:43 GMT -5 ntrain42 said:

Problem is, they measured crosstalk with a narrowband 1khz test tone, not a full range music signal which can be easier to detect and pick up with sensitive ears. Because it sure ain't anywhere near 140db with a full music signal. Regardless, the XPA-2 has some crosstalk as well, but its within an acceptable limit, and its nowhere near as bad as the XPA-3/5 and UPA-5/7.

No they clearly state "Running a full range frequency sweep through the XPA-2 amplifier at full rated power (250wpc @ 8-ohms)"

They simply publish the spec at 1000Hz.