mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 McG, it looks like you have done a good job trouble shooting. You have eliminated the speakers as the potential problem and you have established with science you have a voltage dip from one channel. The question now is what are you going to do about it? Get the AVR to the shop? Find a new AVR? +++ I hate to bring this up, but you may have had this voltage difference from Day 1 and never noticed or measured it until now. I have a Pioneer AVR that is at least 10 years old that has the L/R reversed in the headphone jack. I just discovered it by accident this last summer. So much for my golden ears. It's Monday i am gonna call sony and see if the repair center in NY is the one they will be using and if so then i can be there in 30mins and hopefully see for myself if possible what's wrong with the AVR.Sent from my LG-D855 using Tapatalk Quote Link to comment Share on other sites More sharing options...
mustang guy Posted March 21, 2016 Share Posted March 21, 2016 That's DC, and that multimeter can handle AC frequencies between 40and 100Hz: Set the multimeter on 20V~, and send an 80Hz or so test tone through. Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 (edited) That's DC, and that multimeter can handle AC frequencies between 40and 100Hz: Set the multimeter on 20V~, and send an 80Hz or so test tone through. Ok i will try it and report back. But look at this. Same speaker but Right and Left input. two sweeps on each output on the SAME SPEAKER. Sent from my LG-D855 using Tapatalk Edited March 21, 2016 by MrGrey Quote Link to comment Share on other sites More sharing options...
mustang guy Posted March 21, 2016 Share Posted March 21, 2016 One other thing. Without a load, you may get erroneous readings measuring voltage. You should either use a dummy load or have a speaker connected. 1 Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 One other thing. Without a load, you may get erroneous readings measuring voltage. You should either use a dummy load or have a speaker connected.Ok got itSent from my LG-D855 using Tapatalk Quote Link to comment Share on other sites More sharing options...
BusaDude Posted March 21, 2016 Share Posted March 21, 2016 Just to clarify... Going back to your original post... You're measuring 70 Hz, but the microphone is shown being pointed right at the horn??? There would be no sound coming out of the horn at that frequency. To measure 70 Hz, (in room, to help eliminate room resonances and variables) the microphone should be about an inch away (or closer) to the center of the woofer cone. Did you do that? Measuring a 70 Hz tone from right in front of the horn could easily account for the differences in sound level (at the higher frequencies shown in the graph). Because one speaker (at horn level) is probably closer to a wall or some other object in the room. As a control, have you also measured the voltages from all the other amp channels when playing test tones? Using the same speaker, without moving the microphone, and using the exact same piece of speaker wire? Take those 5 readings (for each channel) playing test tones with speaker 1... Then do the same with speaker 2. And make sure to put speaker 2 in the exact same position as speaker 1 (put some tape on the floor). And don't move the microphone at all. Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 That's DC, and that multimeter can handle AC frequencies between 40and 100Hz: Set the multimeter on 20V~, and send an 80Hz or so test tone through. Nothing shows up when it's on 20v and i play a 80hz or any other tone.Sent from my LG-D855 using Tapatalk Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 (edited) Just to clarify... Going back to your original post... You're measuring 70 Hz, but the microphone is shown being pointed right at the horn??? There would be no sound coming out of the horn at that frequency. To measure 70 Hz, (in room, to help eliminate room resonances and variables) the microphone should be about an inch away (or closer) to the center of the woofer cone. Did you do that? Measuring a 70 Hz tone from right in front of the horn could easily account for the differences in sound level (at the higher frequencies shown in the graph). Because one speaker (at horn level) is probably closer to a wall or some other object in the room. As a control, have you also measured the voltages from all the other amp channels when playing test tones? Using the same speaker, without moving the microphone, and using the exact same piece of speaker wire? Take those 5 readings (for each channel) playing test tones with speaker 1... Then do the same with speaker 2. And make sure to put speaker 2 in the exact same position as speaker 1 (put some tape on the floor). And don't move the microphone at all. I moved it from that position. Pointed it upwards and applied the 90 degree calibration file in Room EQ Wizard. I put the mic a few inches away from the speakers and played a sweep from 40hz to 80hz and the results is what i get above. This is all without moving the mic. Yep same speaker and wire and a new wire also just to make sure.Sent from my LG-D855 using Tapatalk Edited March 21, 2016 by MrGrey Quote Link to comment Share on other sites More sharing options...
BusaDude Posted March 21, 2016 Share Posted March 21, 2016 Assuming an 8 ohm load, 2.83 volts would be 1 watt into those speakers. That would be loud. Set it at 1 volt and try again. Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 Assuming an 8 ohm load, 2.83 volts would be 1 watt into those speakers. That would be loud. Set it at 1 volt and try again.My meter goes from 2volts to 200m no 1v unfortunately.Sent from my LG-D855 using Tapatalk Quote Link to comment Share on other sites More sharing options...
BusaDude Posted March 21, 2016 Share Posted March 21, 2016 Just to clarify... Going back to your original post... You're measuring 70 Hz, but the microphone is shown being pointed right at the horn??? There would be no sound coming out of the horn at that frequency. To measure 70 Hz, (in room, to help eliminate room resonances and variables) the microphone should be about an inch away (or closer) to the center of the woofer cone. Did you do that? Measuring a 70 Hz tone from right in front of the horn could easily account for the differences in sound level (at the higher frequencies shown in the graph). Because one speaker (at horn level) is probably closer to a wall or some other object in the room. As a control, have you also measured the voltages from all the other amp channels when playing test tones? Using the same speaker, without moving the microphone, and using the exact same piece of speaker wire? Take those 5 readings (for each channel) playing test tones with speaker 1... Then do the same with speaker 2. And make sure to put speaker 2 in the exact same position as speaker 1 (put some tape on the floor). And don't move the microphone at all. I moved it from that position. Pointed it upwards and applied the 90 degree calibration file in Room EQ Wizard. I put the mic a few inches away from the speakers and played a sweep from 40hz to 80hz and the results is what i get above. This is all without moving the mic. Yep same speaker and wire and a new wire also just to make sure.Sent from my LG-D855 using Tapatalk Doing that you are going to get a combination of the speakers response and the room resonances at those frequencies. That could easily account for the variances you're seeing. Try it with the mic right in front of the woofer (1 inch or less), from 40 hz to 80 hz, with each amp channel and see what it looks like as a control as I mentioned above. Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 Ok so with 200m setting on the meter the Left channel with the speaker playing is 05.0 - 06.0 and with the Right channel its 06.0 to 07.0 Sent from my LG-D855 using Tapatalk Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 Just to clarify... Going back to your original post... You're measuring 70 Hz, but the microphone is shown being pointed right at the horn??? There would be no sound coming out of the horn at that frequency. To measure 70 Hz, (in room, to help eliminate room resonances and variables) the microphone should be about an inch away (or closer) to the center of the woofer cone. Did you do that? Measuring a 70 Hz tone from right in front of the horn could easily account for the differences in sound level (at the higher frequencies shown in the graph). Because one speaker (at horn level) is probably closer to a wall or some other object in the room. As a control, have you also measured the voltages from all the other amp channels when playing test tones? Using the same speaker, without moving the microphone, and using the exact same piece of speaker wire? Take those 5 readings (for each channel) playing test tones with speaker 1... Then do the same with speaker 2. And make sure to put speaker 2 in the exact same position as speaker 1 (put some tape on the floor). And don't move the microphone at all. I moved it from that position. Pointed it upwards and applied the 90 degree calibration file in Room EQ Wizard. I put the mic a few inches away from the speakers and played a sweep from 40hz to 80hz and the results is what i get above. This is all without moving the mic. Yep same speaker and wire and a new wire also just to make sure.Sent from my LG-D855 using Tapatalk Doing that you are going to get a combination of the speakers response and the room resonances at those frequencies. That could easily account for the variances you're seeing.Try it with the mic right in front of the woofer (1 inch or less), from 40 hz to 80 hz, with each amp channel and see what it looks like as a control as I mentioned above. Ok i will do that give me a minute.Sent from my LG-D855 using Tapatalk Quote Link to comment Share on other sites More sharing options...
BusaDude Posted March 21, 2016 Share Posted March 21, 2016 Assuming an 8 ohm load, 2.83 volts would be 1 watt into those speakers. That would be loud. Set it at 1 volt and try again.My meter goes from 2volts to 200m no 1v unfortunately.Sent from my LG-D855 using Tapatalk I couldn't see the multimeter photos (I was on my phone) in the original post... it looks like you were getting 6 or 7 millivolts from your original measurements. Go back to the 200 m setting and you should be able to see what is going to the speaker. I suggest the close mic'd placement because, in this instance, you're not trying to get the frequency response of your speakers in your room. But, rather, trying to see the possible difference between the amp channels output. And at a few millivolts, getting the mic as close as possible to the woofer (less than an inch) will help eliminate your room's influence. Quote Link to comment Share on other sites More sharing options...
BusaDude Posted March 21, 2016 Share Posted March 21, 2016 (edited) Ok so with 200m setting on the meter the Left channel with the speaker playing is 05.0 - 06.0 and with the Right channel its 06.0 to 07.0 Sent from my LG-D855 using Tapatalk Did you measure the decibel level at those values? In your original post, there was a 3 dB difference between the channels. To go from 84 dB to 87 dB would require a doubling of the input voltage. A 1 millivolt difference (assuming 8 ohms and constant amperage) wouldn't be enough to explain it, but 4 millivolts or more (in a 6 millivolt range) would be close to doubling the power. Though we're talking about the difference of a few thousandths of a watt. I'd still check the variance between all 5 channels to see if they are in the same range. If they are, and just that one channel is putting out more/less than the others, then you'd know the difference was the amp. Edited March 21, 2016 by GPBusa Quote Link to comment Share on other sites More sharing options...
babadono Posted March 21, 2016 Share Posted March 21, 2016 OP, you need to be doing AC measurements, not DC. Who cares if there is a 1 millivolt DC difference in your AVR outputs. Speakers do not like any DC voltage but a tiny amount they will usually tolerate. Your meter needs to be set at the 200 or 600 V AC scale. The lower setting (200V) will be more accurate(as pointed out by MustangGuy) and should suffice for your AVR outputs. Oh and Welcome to the Klipsch Forum........ and the madness. 1 Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 Now this is what i got. Quote Link to comment Share on other sites More sharing options...
Max2 Posted March 21, 2016 Share Posted March 21, 2016 That's weird. I'm guessing you have already tried a different AVR or power source and ruled out speaker issues by swapping them? If not, I would be hoping the channel separation or crosstalk is a good bit off on the unit. Is there a speaker setup on the AVR that will send out the same level signal to each speaker? Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 The results keep jumping around. Do you recommend opening up anything? Sent from my LG-D855 using Tapatalk Quote Link to comment Share on other sites More sharing options...
mother's corpse Posted March 21, 2016 Author Share Posted March 21, 2016 That's weird. I'm guessing you have already tried a different AVR or power source and ruled out speaker issues by swapping them? If not, I would be hoping the channel separation or crosstalk is a good bit off on the unit. Is there a speaker setup on the AVR that will send out the same level signal to each speaker?This is the only avr i have. And i swapped the speakers around. I have the sony STR-DH550.Sent from my LG-D855 using Tapatalk Quote Link to comment Share on other sites More sharing options...
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