Amplifier problem

[Dwaindibly]

Hi newbie here looking for some advice I have a marantz pm6007 I've had it around 10 months now it sounds great but lately something about the imaging from the left speaker has been bothering me. it sounds like some of the image to the far left is missing I went back to basics as my room is in the loft with an apex ceiling so its a difficult room acousticly and it now sounds a little better now but the left channel is still missing some detail. I have confirmed this with a test track it can't seem to image left of the left speaker the same as the right I think it could be my amp as I swapped channels over and the same problem occurred with the right speaker and the left image well
Can anyone advise ?
Thanks

 

[DonH56]

Hi newbie here looking for some advice I have a marantz pm6007 I've had it around 10 months now it sounds great but lately something about the imaging from the left speaker has been bothering me. it sounds like some of the image to the far left is missing I went back to basics as my room is in the loft with an apex ceiling so its a difficult room acousticly and it now sounds a little better now but the left channel is still missing some detail. I have confirmed this with a test track it can't seem to image left of the left speaker the same as the right I think it could be my amp as I swapped channels over and the same problem occurred with the right speaker and the left image well
Can anyone advise ?
Thanks

Assuming it was OK before, and that as you say the problem followed the amplifier channel and not the speaker, then it could be a bad amplifier channel. I would suggest turning off room correction and see if that changes anything, re-running the room correction program (Audyssey, I think, for Marantz), and/or performing a factory reset (may have to search online for the procedure to do a full reset) then running Audyssey to see if it corrects itself. It's possible a power (or other) glitch has corrupted settings and a reset and re-run may be required to get them back.

 

[Dwaindibly]

It's a basic amp so no room correction

 

[Doodski]

If you are convinced the imaging is wonky on the left side then take the amp in for service.

 

[DVDdoug]

I'm not sure what you mean by imaging or detail... A left-right imbalance? In that case the "center" would seem to be off-center.

The REAL characteristics of "sound quality" in electronics are noise, distortion, and frequency response. (With speakers and room acoustics things get a little more complicated but frequency response is the main thing with speakers.)

The most likely problems would be a dead channel (not the issue) or distortion in one channel, but you'd probably hear that as distortion rather than an imaging problem.

A frequency response error/variation in one channel would be very unlikely.

If you are comparing left & right you should be playing a mono file and it's probably worthwhile to test the channels one at a time with the same speaker. Audacity can make mono file and it can make white noise or pink noise files.

 

[Dwaindibly]

It's still under warranty so it's going back if its faulty I'm going to swap back to my old amp and see if the problem is still there then I'll know if its the amp or something else upstream

 

[AnalogSteph]

For a test, swap over the speaker cables from left to right and vice versa, as well as left and right RCAs on your audio input (of when using the built-in DAC, do so in software or just play something mono). If the problem moves over to the right channel you know it's the amp, if it doesn't then it probably isn't. Ah, I see you may have already done that:

I have confirmed this with a test track it can't seem to image left of the left speaker the same as the right I think it could be my amp as I swapped channels over and the same problem occurred with the right speaker and the left image well

That's not looking good for the amp then. Maybe it's got a duff protection relay or something.

 

[Dwaindibly]

OK so when I play this test from YouTube I can place every point equally on the right past the speaker upto the centre but when it moves over to the left its fine until it gets to the point at the speaker the last 2 don't move futher left like the right does

 

[DonH56]

It's a basic amp so no room correction

OK. If it is the same problem on every source, and the problem does not happen when you switch amp channels to the speakers as you said earlier, then there must be something wrong with the amp. It could be one of many things but if they are all inside the amp then return it for warranty repair.

This all assumes the test is passing when you switch L/R amp channels to the speakers, so the left speaker is OK, but the right fails after swapping amp channels.

 

[GXAlan]

Can you try swapping your speaker leads (the black and red) to see if it’s a phase problem?

 

[Dwaindibly]

The plot thickens!! Different amp Different source same problem could it be the recording or Bluetooth quality as I have to Bluetooth the YouTube video to my Wiim and also the amazon echo I used as a Different source so this could be the issue maybe. I can't seem to find a similar test on tidal can anyone recommend a good quality test track that's similar

 

[Old_School_Brad]

Have you tried physically swapping the speakers?

 

[MaxwellsEq]

If it's always to the left, have you checked your hearing? I have tinnitus which varies day to day and is worse when I am tired. Sometimes I have issues with images not being centered, but which are fine when the tinnitus is less bad.

 

[Dwaindibly]

I have a great phantom centre it's bang on it might just be the room and my brain/hearing there just seems to be a fuller sound from the right

 

[antcollinet]

I have a great phantom centre it's bang on it might just be the room and my brain/hearing there just seems to be a fuller sound from the right

It is almost certainly room interaction. I had a sound stage sloping down to the left. I traced it to the position of my sub which (due to small room) is in front of the left speaker. Reflections from the top of the sub were causing the issue. Putting a cushion on top of the sub fixed it.

Look for sound absorbing stuff to the left of your left speaker. Imaging outside of the speakers often relies on early reflections from the wall on that side. Alternatively is the room symmetrical left to right (including wall/reflective surface materials). If not that will likely cause a sound stage imbalance.

Alternatively if different source/amp has the same issue, and swapping speakers/cables moves the problem left to right (following speaker or cable) then it could be a speaker fault. But when testing this, be sure to postion speakers identically - including toe in etc. Mark the floor position with tape.

 

[Steven Holt]

Have you tried physically swapping the speakers?

That should be his first step. Marantz makes high quality gear, and I strongly suspect the problem is in his speakers.

 

[Old_School_Brad]

That should be his first step. Marantz makes high quality gear, and I strongly suspect the problem is in his speakers.

It should.
It could also be due to the room. If the side walls are asymmetrical or there’s an opening, the image may be drawn to one side. However, I would begin with a physical swap to ensure there’s no issue with the speakers.

 

[Dwaindibly]

Speakers and cables swapped for left to right etc my gut says it's the room or the amp as i bought it from hyperfi as a grade b which means it's been sent back to marantz for whatever reason tested and checked then resold by hyperfi with a 12 month warranty. the room is asymmetrical as the celling slope is lower on the left but thats all .I've tried a near field arrangement as suggested with no change all first reflection points have been treated with panels on the walls or hex tiles on the ceiling. the centre stage is spot on but the rest seems skewed over to the right might start pinning up duvets now to see if there's any change and go for a hearing test

 

[Doodski]

Speakers and cables swapped for left to right etc my gut says it's the room or the amp as i bought it from hyperfi as a grade b which means it's been sent back to marantz for whatever reason tested and checked then resold by hyperfi with a 12 month warranty. the room is asymmetrical as the celling slope is lower on the left but thats all .I've tried a near field arrangement as suggested with no change all first reflection points have been treated with panels on the walls or hex tiles on the ceiling might stat pinning up duvets now to see if there any change and go for a hearing test

Have you tried headphones to see if there is a difference from side to side? Usually the headphone amp is the speaker amp so they will be nearly one and the same as per if there is a issue.

 

[Dwaindibly]

Has anyone played the YouTube test on there system that i posted earlier ?
Just wondering if it's a poor recording