Got a tough one that I could use some help with. For some reason, even though nothing physically changes with my system, I seem to loose the 'staging' of my music. Some days the vocals are really tightly centered between the speakers, and it sounds amazing. Other times, it's as though the focus is gone and I more hear the music from both the speakers instead of centered. It's very frustrating and I cannot think of what would be causing this.

A few answers to questions that I'm sure to be asked.

- No, I am not moving the speakers at all, nor am I moving my listening position. All are pretty much fixed in place. They are monitor audio gr 60's.

- I used a laster pointer to focus the 'sweet spot' approx 2' behind my chair.

- My primary audio source is my xmeridian soundcard using analog outputs to my denon 5800 premamp. I have changed the opamps on the card, and bypassed the caps. There is no measurable amount of dc going through the card so the surgery was successfull.

- My secondary audio source is my 'tubed' denon 3910, it exhibits the same issues now.

- All music on the pc is ripped lossless

- I have treated the room with 705 for all reflection points, including front wall, and the entire rear wall. Also have floor-ceiling bass traps which did help a ton.

I'm almost wondering if the xm card has hurt my preamp. Many people were complaining about how 'hot' the card is outputting much more current than most equipment. Even though many others said they could never turn their volume on the pc above 40% without distortion, I never had that problem. I have found that I am using MUCH higher volume levels on the 5800 than I ever have before. In the past I rarely had the preamp above 18 on the dial where now I find I am always very close to 0 which is reference level on the preamp.

Has anyone heard of a preamp going bad in such a way? I would figure it would just stop working if it broke, instead I find my imaging 'comparably' sucks and the volume levels are having to be raised a ton to get decent levels. (And no, it's not the room accoustic treatments as I was using them prior to the problem)



Well that's about it... hoping maybe someone has a good idea as to what might be wrong.

Nobody answering eh. OK, start by telling me a bit more about what you are hearing. Is something really changing from day to day, as in an equipment malfunction? Or is this a subtle thing, something that a guest that doesn't know your system well wouldn't even notice but you do?

What preamp is involved? Try changing to a different set of inputs on the preamp.

The simplest debugging would be to swap in a comparable preamp and see if the soundstage issues go away.

PCs can be quirky. Make sure the sound card and playback software settings have not changed, as well as audio codecs. What is weird is that your Denon is also not sounding right from a soundstage perspective.

My guess is that some of the source recordings are not as good as others.

- Steve O.

Do you live in a heavily populated area?

Something to consider would be the AC feeding your system. There may be more noise on the lines when you are experiencing the problematic issues. Noise coming from appliances within your home, your neighbors appliances, cell phone activity, wireless internet, etc..

Make notes of the times when the sound is bad, and when the sound seems to be better. Usually, if it is the AC lines feeding grunge into your system, your system will sound better late at night when there is less activity.

A voltage regulated power conditioner with EMI and RFI filtering might be worth inserting into your system at some point. In fact try several different makes and models if you can.

I would also start by taking the computer out of the equation. Just use the Denon exclusively as the source until you get the issue figured out. Computer source introduces too many variables.

I doubt now is the right time to buy A/C power filters or balanced units. Once you have your system settled down, it's a nice way to drop the noise floor.

RF noise from cellphones or wireless phones would exhibit audible noise - buzzing/humming. Probably not a collapse of audio soundstage. 802.11 is at a frequency not even audible, like television and microwave data transmission.

I have a feeling on your PC source, the new op amps on your sound card are biased with a higher than normal power supply and perhaps might be affected by heat. I would swap back the original op amps (if they are socketed) and see if things settle down.

Good luck,

- Steve O.

I doubt now is the right time to buy A/C power filters or balanced units. Once you have your system settled down, it's a nice way to drop the noise floor.

RF noise from cellphones or wireless phones would exhibit audible noise - buzzing/humming. Probably not a collapse of audio soundstage. 802.11 is at a frequency not even audible, like television and microwave data transmission.

I have a feeling on your PC source, the new op amps on your sound card are biased with a higher than normal power supply and perhaps might be affected by heat. I would swap back the original op amps (if they are socketed) and see if things settle down.

Good luck,

- Steve O.He says he sees the same sympton with the CD player as the source.

He says he sees the same sympton with the CD player as the source.

That's why I suggested to debug the preamp first.

- Steve O.

I had a very old Integra amp that died a few years ago (I killed it, actually, but that's another story). It's first sign of death was that about six months prior the right channel would be down 5-10 dB in volume for about ten minutes after first turning it on until it warmed up. Gradually it got worse and worse until finally it started shutting down while playing music and that was the end. While this was occuring, it totally destroyed imaging and detail between my speakers. So yea, you could be seeing the first signs of equipment failure.

Doug

Doug

I've experienced this phenomena before, and notice that my system sounds better at night. Not sure if I just like listening better at night or if it powerline related. Either way my system sounds great, I just seem to get more wow at night. By the way my powerline voltage usually reads 121 volts at night, and 118-119 during the day.