Different & inconsistent sound quality

I am noticing different sound quality from my audio system, depending on when I listen to them. My system consists of Krell integrated amp, B&W CDM 1SE, and Sony DVP-7700. They are connected with Transparent ML Super interconnect and MIT T2 Biwire speaker cable. For example, in the moring and very late night, piano recordings sound very clean, detailed, and transparent, however, in late afternoon or evening, it seems that some of piano notes from the same CD sound very dull and veiled. The phenomenon is true of other recordings of cello, violin, and etc. I suspect that AC noise has to do with the problem, so as a first step, I consider upgrading stock power cord for my integrated amp to a better one such as Transparent PowerLink Super or others. Could anyone help me with any possible solutions to the problem I'm experiencing? Any suggestions or comments would be greatly appreciated.
I experience the same thing. Lots of microwave energy where I live (near Cape Canaveral, KSC) also there is more active radio interference during the day than late in the evening or early morning. Without some type of filtering there isn't much you can do. Sounds like you might want to check out one of those PS Audio P300 power generators, would certainly help you with clean power and filtering out the nasties that is affecting enjoyment of the system. I bought a pair of Enacoms passive RFI filters, that helped. Audio Prism also has a product called quiet lines that plug into the wall outlet I have heard that the work well. Both of the above are inexpensive and are probably a good place to start.
Hi. Dito from the comments made by Tubegroover, as I own or have owned all the products mentioned. Also, if you have the means, a nice dedicated 20 amp curcuit for your system would do very well. Also, checking your system grounds is also important. Happy listening! Regards, Bill M.
I always wondered if it was just me or other people noticed the change is sound quality too. I knew I wasn't imagining it, but always wondered if the situation was common. Anyway, I use two of the Blue Circle Noise Hounds now, and have found much more consistent sound quality in my system. I had tried some power cords, which made some sonic differences, but did not make the sound any more consistent. Whereas the Noise Hounds made the system sound as good during the day as it does late at night. Thus, the hypothesis of noisy lines certainly seems believable to me.
Definitely you have noisy power. PS 300 is not a cheap one. I suggest the dedicated line +ground separate and some power line conditioner. At least a HTS 2000 from Monster at 200.00 retail could be a fix if there's the 1000 I think versio cheaper but with less plug capabilities. Check monster site. Generally amps do better direct to wall so new power cord is a sound option.... Best with dedicated line. Regards
Thanks so much for responses. They were quite informative and helpful. I guess that power noise problem seems to be a more seious matter than I initially thought. I will look into all the suggestions and report back what happens. Thank you so much again!!
As well as dirty power lines, the outside noise seriously effect the backround blackness of sound. This noise can not be heared directly so we don't mind so much but if you check with dB meter in the night and afternoon, it is really so much. Also, I compared many power cables and I made some myself, eventually I found a magic power cord, sidewinder (www.powersnakes.com) This cable makes unbelieve differency on smoothness and blackness of the soundstage, give a try you will seee immediately (You may order long and cut to two or three without any problem)
You might also consider the difference in your ear's sensitivity at those extreme times of the day. Your ears will naturally become less sensitive when the environment is noisy (loud). And then at night, or early morning, they can pick up the slightest details. Try wearing ear plugs for an hour or so, and then take them out to see what I mean.
Maybe that explains why my system always sounds so good. I wear earplugs 8 hours a day at work.
This is a very important topic. The fact that my system(s) sound better late at night, early in the day, and on Sunday has been bugging me for years. There seems to be a definite correlation between power usage on the line and sound quality. Sound is noticably better in the middle of the night when power usage is at a minimum. The problem is that no matter what power cords, power conditioners, filters, etc. I put in the system, some of which do improve the sound, this problem never goes away. Is there a solution?
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Definitely, power -- may I be so definite? The local electrician was absolutely definite on this point (no joke). He mentioned the TV, too.
I live in the old continent; my 230V equipment refuses to reproduce clear bass under 220V. I claim to "hear" the difference when the neighbours' stove & heater switches off--through my speakers. Easy to do when you live, as I, in a flat...
But then, how often can we stay up to 3am to enjoy music?
A very good thread indeed! All above posts bring out the real experiences and make sense from engineering principles. I too found various successes in using some of the methods mentioned. However, i have a little reservation on Oatalay's method of cutting the pc into shorter lengths. Best to check with Powersnakes what's the MINIMUM length which will do the job. In eng'g sense, the conductor size, dielectric material, geometry(twist & formation), grounding and length all account to the effective "filtration" the pc designer is aiming to achieve.
I use Chang CLS6400 ISO, NBS Dragonfly II & AudioPower 313(obsolete?) pc's. They are not top of the line but they do a fine job on my tubed system which has a low current demand. I changed the Chang's feeder to a Belden foil shielded 3X14 Awg powersupply cable; connecting the drainwire to Chang's metal chassis, thus voiding my warranty right. I did this because my 20A powersocket is wired through metal conduits. The foil & drainwire serve as an extension of the conduit system. Please do not attempt this unless you are a qualified electrician. Regards.