capn
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Post by capn on Oct 27, 2018 23:23:32 GMT -5
The main left and right outputs on my XMC-1 differ by approximately 1.5 dB across the whole audible frequency spectrum when in Reference Stereo mode (when the input source material is identical in both left and right channels). I know that isn't right, but I'm curious to hear how closely matched these outputs typically are from other owners who have tested them.
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Post by garbulky on Oct 28, 2018 1:49:10 GMT -5
The main left and right outputs on my XMC-1 differ by approximately 1.5 dB across the whole audible frequency spectrum when in Reference Stereo mode (when the input source material is identical in both left and right channels). I know that isn't right, but I'm curious to hear how closely matched these outputs typically are from other owners who have tested them. THey should be 100% matching. However if you simply measured the SPEAKER volume in the room then it's more likely that one of two things happened. 1. Your speakers are not wired in phase. . Go here and play the phase test. 2. Your room acoustics/speaker placement and interaction with the room are causing the mismatch. If you speakers are in a corner this could easily explain it. |
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Post by AudioHTIT on Oct 28, 2018 5:48:09 GMT -5
The main left and right outputs on my XMC-1 differ by approximately 1.5 dB across the whole audible frequency spectrum when in Reference Stereo mode (when the input source material is identical in both left and right channels). I know that isn't right, but I'm curious to hear how closely matched these outputs typically are from other owners who have tested them. We need to know how you measured this? Like garbulky mentions, if your using a mic then room interaction could cause a 1.5 dB difference, if you’re measuring the output of the XMC-1 and all the trims are set to 0, then there’s something wrong. |
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capn
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Post by capn on Oct 28, 2018 8:00:26 GMT -5
I measured this like so. 1. First, I generated a stereo chirp in audacity from 100 Hz to 15KHz with equal volume across frequencies and channels. Rate was 96 KHz and depth was 24 bit. Test #1 Played the file via coax 3 input to XMC-1, set the mode to "Reference Stereo" and recorded the output of the LF and RF balanced outputs via Lynx HILO ADC balanced inputs. The recorded result can be downloaded here: app.box.com/s/z73bvp27pt6kf4ez5rabzttmr3duuu5qTest #2 Played the file via optical 3 input to XMC-1, set the mode to "Reference Stereo" and recorded the output of the LF and RF balanced outputs via a different set of cables from test #1 using MOTU 828mkII ADC balanced inputs. It showed the same discrepancy |
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Post by 405x5 on Oct 28, 2018 9:04:27 GMT -5
That level of discrepancy....have you done a listening test after SPL compensation and making those levels persistent in your configuration settings?
If there is no audible problem there I would simply walk away from this.
You could also swap the mains to eliminate anything going on with the loudspeaker.
Bill
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DYohn
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Post by DYohn on Oct 28, 2018 9:15:42 GMT -5
Did you run the XMC-1 setup routine and Dirac? Also, hearing a 1.5dbSPL difference is difficult.
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capn
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Post by capn on Oct 28, 2018 9:28:56 GMT -5
Did you run the XMC-1 setup routine and Dirac? Also, hearing a 1.5dbSPL difference is difficult. I did setup the number and type of speakers in my system, if that is what you mean. I did subsequently run Dirac room correction, too. However, it is my understanding that "Reference Stereo" mode should bypass all processing including Dirac. My beef is that "Reference Stereo" should be as pristine as possible, and to me that includes good balance on the left and right output levels, particularly when there is no balance adjustment available on the XMC-1. |
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DYohn
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Post by DYohn on Oct 28, 2018 9:56:12 GMT -5
In the Setup menu you can adjust the levels of the speakers. This should haver been set automatically during initial room setup, but since you are annoyed by this level difference I recommend you go into the speaker level settings meu and make a permanent adjustment. This is your "balance" control.
Note that the XMC-1 is not an analog preamp. It is a very sophisticated computer processor. Even in "reference stereo" mode.
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Post by 405x5 on Oct 28, 2018 9:59:35 GMT -5
I measured this like so. 1. First, I generated a stereo chirp in audacity from 100 Hz to 15KHz with equal volume across frequencies and channels. Rate was 96 KHz and depth was 24 bit. Test #1 Played the file via coax 3 input to XMC-1, set the mode to "Reference Stereo" and recorded the output of the LF and RF balanced outputs via Lynx HILO ADC balanced inputs. The recorded result can be downloaded here: app.box.com/s/z73bvp27pt6kf4ez5rabzttmr3duuu5qTest #2 Played the file via optical 3 input to XMC-1, set the mode to "Reference Stereo" and recorded the output of the LF and RF balanced outputs via a different set of cables from test #1 using MOTU 828mkII ADC balanced inputs. It showed the same discrepancy Those are direct measurements, not microphone, correct? You should run those by Tech. support and see what they say. ( you may be shipping to Franklin) Is reference the only mode the anomaly appears? Bill |
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Post by audiosyndrome on Oct 28, 2018 11:38:00 GMT -5
In the Setup menu you can adjust the levels of the speakers. This should haver been set automatically during initial room setup, but since you are annoyed by this level difference I recommend you go into the speaker level settings meu and make a permanent adjustment. This is your "balance" control. Note that the XMC-1 is not an analog preamp. It is a very sophisticated computer processor. Even in "reference stereo" mode. I’m under the impression, as in a post above, that in the reference stereo mode, the XMC-1 is simply an analog pass through. In other words, any “adjustments, settings, etc.”, are ignored. It would be a nice to have balance control in reference stereo in order to compensate for downstream issues, some of which are mentioned above. Russ |
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DYohn
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Post by DYohn on Oct 28, 2018 11:59:12 GMT -5
In the Setup menu you can adjust the levels of the speakers. This should haver been set automatically during initial room setup, but since you are annoyed by this level difference I recommend you go into the speaker level settings meu and make a permanent adjustment. This is your "balance" control. Note that the XMC-1 is not an analog preamp. It is a very sophisticated computer processor. Even in "reference stereo" mode. I’m under the impression, as in a post above, that in the reference stereo mode, the XMC-1 is simply an analog pass through. In other words, any “adjustments, settings, etc., are ignored. It would be a nice to have balance control in reference stereo in order to compensate for downstream issues, some of which are mentioned above. Russ From the owner's manual: In Reference Stereo Mode: • The output is always TWO CHANNEL STEREO. • There is NO bass management, and NOTHING is sent to the subwoofer. • You CANNOT use the Loudness Control, or the Tone Presets, or the Tone Trims. • You CANNOT use Dirac Live or the manual Parametric EQ Presets. • Level Trims, which operate in the analog domain, are still available. • Speaker Distance adjustments are active for digital inputs but not for analog inputs. • Stereo analog input signals are passed straight to the Volume Control and the outputs. • Stereo digital input signals are converted to analog then sent to the Volume Control. • Surround sound digital signals are decoded, mixed down to stereo (the Center Channel and LFE signals, if present, are mixed into the stereo output), and converted to analog. |
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Post by audiosyndrome on Oct 28, 2018 12:01:25 GMT -5
I’m under the impression, as in a post above, that in the reference stereo mode, the XMC-1 is simply an analog pass through. In other words, any “adjustments, settings, etc., are ignored. It would be a nice to have balance control in reference stereo in order to compensate for downstream issues, some of which are mentioned above. Russ From the owner's man ual: In Reference Stereo Mode: • The output is always TWO CHANNEL STEREO. • There is NO bass management, and NOTHING is sent to the subwoofer. • You CANNOT use the Loudness Control, or the Tone Presets, or the Tone Trims. • You CANNOT use Dirac Live or the manual Parametric EQ Presets. • Level Trims, which operate in the analog domain, are still available. • Speaker Distance adjustments are active for digital inputs but not for analog inputs. • Stereo analog input signals are passed straight to the Volume Control and the outputs. • Stereo digital input signals are converted to analog then sent to the Volume Control. • Surround sound digital signals are decoded, mixed down to stereo (the Center Channel and LFE signals, if present, are mixed into the stereo output), and converted to analog. What I said. Russ |
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Post by garbulky on Oct 28, 2018 12:09:13 GMT -5
Well a 1.5 db difference - though may not be very audible IS an issue and it shouldn't be so especially on gear of this calibre. I suspect that it is a setup issue with one of the electronics and not an actual problem with the XMC-1. I would call Emotiva and check out what the deal is.
It's probably the level trims that caused this difference.
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DYohn
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Post by DYohn on Oct 28, 2018 12:23:07 GMT -5
From the owner's man ual: In Reference Stereo Mode: • The output is always TWO CHANNEL STEREO. • There is NO bass management, and NOTHING is sent to the subwoofer. • You CANNOT use the Loudness Control, or the Tone Presets, or the Tone Trims. • You CANNOT use Dirac Live or the manual Parametric EQ Presets. • Level Trims, which operate in the analog domain, are still available. • Speaker Distance adjustments are active for digital inputs but not for analog inputs. • Stereo analog input signals are passed straight to the Volume Control and the outputs. • Stereo digital input signals are converted to analog then sent to the Volume Control. • Surround sound digital signals are decoded, mixed down to stereo (the Center Channel and LFE signals, if present, are mixed into the stereo output), and converted to analog. What I said. Russ Yep. And what I said too. |
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Post by AudioHTIT on Oct 28, 2018 12:34:27 GMT -5
We still need clarification if the measurements are made with a microphone, or a level meter directly from the XMC’s output at the Lynx device mentioned. So, is it an acoustic measurement or an electrical measurement? The former should be compensated for, the later should be fixed.
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Post by amped on Oct 28, 2018 13:09:06 GMT -5
My question is what caused you to measure in the first place? Did you notice something audible in your listening or did you just set out to test reported measurements? Now for my 2 Cents if you want to critically listen in 2 channel then set up a 2 channel system. Trying to get "reference" sound from a piece of home theater gear is not gonna happen. Been there done that! Manufactures like to throw around the word "Reference" and write it in cursive on their gear to try and lend it some credibility but 95% of the time its rhetoric so they can saturate a wider market. That's why I still LOVE my Sherbourne 7030 HT processor it decodes multi channel and that's what I want.
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capn
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Posts: 39
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Post by capn on Oct 28, 2018 14:41:19 GMT -5
To address a couple of questions that have come up:
1. The reason I started down the path of measuring this is because I perceived one channel was louder than the other coming from the speaker. Now, that could have been partially attributed to the source material, because I was just listening to music (I can't recall the song). So to eliminate the source, I set about to make the measurement.
2. There are no speakers or microphones involved in the measurement. The path is: chirp wav file (96Khz, 24bit)->XMC-1 coax 3->XMC-1 balanced LF/RF outputs->Lynx HILO balanced inputs with XMC-1 in reference stereo mode.
I was hoping to find a trim level offset setting that was responsible for the 1.5 dB delta, but thus far, I have not found it.
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DYohn
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Post by DYohn on Oct 28, 2018 15:24:55 GMT -5
To address a couple of questions that have come up: 1. The reason I started down the path of measuring this is because I perceived one channel was louder than the other coming from the speaker. Now, that could have been partially attributed to the source material, because I was just listening to music (I can't recall the song). So to eliminate the source, I set about to make the measurement. 2. There are no speakers or microphones involved in the measurement. The path is: chirp wav file (96Khz, 24bit)->XMC-1 coax 3->XMC-1 balanced LF/RF outputs->Lynx HILO balanced inputs with XMC-1 in reference stereo mode. I was hoping to find a trim level offset setting that was responsible for the 1.5 dB delta, but thus far, I have not found it. Check your owner's manual. |
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Post by Jean Genie on Oct 28, 2018 17:54:42 GMT -5
Move your chair 2.5 inches.😎
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Post by foggy1956 on Oct 28, 2018 18:14:02 GMT -5
In the Setup menu you can adjust the levels of the speakers. This should haver been set automatically during initial room setup, but since you are annoyed by this level difference I recommend you go into the speaker level settings meu and make a permanent adjustment. This is your "balance" control. Note that the XMC-1 is not an analog preamp. It is a very sophisticated computer processor. Even in "reference stereo" mode. I’m under the impression, as in a post above, that in the reference stereo mode, the XMC-1 is simply an analog pass through. In other words, any “adjustments, settings, etc.”, are ignored. It would be a nice to have balance control in reference stereo in order to compensate for downstream issues, some of which are mentioned above. Russ Level trims which operate in the analog domain work very well for balance control on the xmc-1 |
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