Thanks both for your comments. A long time ago I had a similar problem with My B&W 803N. I asked my dealer and he said make sure nothing is connected to TV or Cable. I disconnected my CD/DVD from TV and that fixed the problem. The hiss is identical but so far nothing has worked. I am confident the moise is not from any one component since I have at least two of everything and changing amps, preamps, PC, IC, does not help. So I think there is a simple solution but I haven't figured it out yet. I'll keep on trying everything you have suggested and hopefully put this problem behind me and enjoy the music. Thanks all. |
Espoverload, A cheater plug is a plug with the old fashion 2 blade connector with the big round ground blade removed. You plug your 3 blade PC into it then you plug it into you outlet.
While it is always nice to have one in the drawer to use if you think you might have a ground loop, or where it is, I doubt that is your problem based on the sound you are describing. |
Espoverload
Sorry I just reread that you have tried new amps etc. Forgive me for being dense. If you know some one with a power conditioner that may be an easy test. Also several years ago I noticed my lights in my house dimming at erratic intervals. This kept happening and it worried me so I had the electric company take a look at my power. On the outside of your house is a a meter. It is fed on three legs. Each leg must read equal voltage. Mine did not. Upon investigation the power company tech said one of the leads was loose at the box in the back yard. This box fed 2 or 3 houses. It is sounding like you have a power problem in your house. Some fluke meters (voltmeters) have ocilliscope screens so you can take a sample of the power at your outlet and see if there is some large scale noise in your ac supply. Good luck! |
I forgot to mention that the other day I was hearing a buzz or spit intermitantly on the left speaker and was worried that a tube was going bad or worse one of the amps! After investigating all my connections etc. I found one interconnect was laying directly against a power cord (perpendicularly by the way). This power cord was feeding the preamp and I'll be damned, that was it. Repositioning the interconnect fixed it. When the noise is occuring try taking a wire and touching to both the amp and preamp to see if the noise worsens or lowers. Do you have a friend with a different preamp that you could see if this goes away? |
Newbee, Thanks for the detailed response. I Understood your response to the last thread and that's how I isolated the problem to the preamp. The noise is a high frequency distortion (hiss) only heard in the mid-range and the tweeter at high volume. As I stated in this thread, my pre and source have only SE in/out. So in order to try balanced connection, I have to purchase a new pre and good IC. Again, I am happy with the sound of the system and I don't need to upgrade at this time. However, if that's what it takes to get rid of the noise I'll do it. But different members have different points of view. Some say XLR makes no difference unless you have very long runs and some indicate it makes a big difference. That's why I'd like to try everything else before committing to buy more gear. I'll try your suggestion on disassembling the entire system and tryng to isolate the source of the interference. I do have several PC's, IC's, RGPS transformer in close proximity to each other. Also my amps and preamp are very high gain and speakers are 8 Ohms with 91db sensitivity. I'll try some more thigs as suggested and post the results.
BTW, what is a cheater plug? Thanks for your help. |
Espoverload, I briefly revisited your earlier thread in which I participated. Mihalis sort of mirrors my thoughts here. I though you had solved your noise problem when you used some XLR connectors on your amps? Not so?
One thing that might be helpful would be if you could more specifically describe the 'noise' or 'distortion' that you are hearing, i.e. is it a buzz in the lower frequencies which you clearly hear when you put your ear near(er) the mid range or bass, or a higher frequency constant hiss heard more clearly with your ear near the tweeter. You use the word 'distortion' and that covers way too wide a range of possibility of sounds.
Another thing to consider is I/C and PC dressing. PC's and transformers too close to I/C or other components can cause problems. As (IF) you follow my recommendation include an examination of their condition and their placement so you will know if it is the source of the noise.
If I had your problem this is exactly what I would do. Disconnect everything from your amps (except speakers of course). Disconnect these components PC's from outlets.
Then carefully reassemble, one component at a time and identify exactly when this noise appears. For example, when you connect your preamp first connect it to the amp but don't plug it. Listen. Any noise? No? OK then plug it in. Any noise? Yes? Pull the PC from the wall of conditioner and add a 'cheater plug'. Still have noise. OK disconnect PC and remove 'cheater plug'. Noise goes away - OK you now have identified your problem as a ground loop caused by your pre-amp. If the noise doesn't go away consider that you may beed dealing with the pre-amp(s) noise floor. They all have one - whether you hear it or not depends on speaker efficiency, amp sensitivity and gain issues. Pre-amps with high gain and speakers with high efficiency for example will regularly have noise issues which will be aggravated by speaker input sensitivity. I'm assuming the noise if the result of the pre-amp for this drill, but if you should continue the drill thru the addition of source components to see if any differences occur as they are added.
If after this drill you can't find a source, consider that the problem may be riding on your houses wiring and or other domestic items on the same circuits as your audio stuff.
It will be very helpful to anyone trying to help you if you can present a thorough, detailed, description of exactly what you have, what you have done, and the results of each transaction.
BTW your first drill will be in breaking this long winded exercise down into some easy to absorb pieces. :-)
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Thank you for great comments.
Mihalis, As far as changing amps and preapms, I have done all that with no positive results. My interconnect runs are less than a foot so the length can't be an issue. Nither of my preamps have external gain control.
Booboobaer, I am glad you confirmed that it is possible to hear no noise from you speakers at maximum output with no source. I was begining to think this is a normal anomaly. I have tried various speakers as well and the noise is still there. since there is no noise from the amp with no connection to the pre. the problem is isolated to the pre unless there are other factors involved. My system sounds very good, at least to my ears, but it's one of those thing that you want to find a reason for and ultimately a solution. The only reason I have not yet decided on a new tubed amp and XLR connection, is that I have no reasonable degree of assurance that after spending another several $K, I will eliminate distortaion. Since I have tried multiple amps, preamps, speakers, power cords, wall socket, etc. without any result, I am in a dilemma to purchase another piece of equipment. So I am hoping one of the members with the same problem can help. All comments are very valuable and I welcome all. Thank You |
I have tried passive before and it does sound clear but thin in most cases. XLR was developed to reduce noise in very long runs of cables for bands. It works very well ask any band member of any clout if they use RCA and they will chuckle. I have a BAT VK51SE preamp and I have to say it is VERY quiet! The RCA cable was originally designed for tone arm connections (short lengths). I have had single ended cables and XLR both and I must say balanced is DEAD Silent. You can see my system and see that I am VERY serious about the sound. You can turn on the system and turn the volume to max without the cd playing of course and barley hear audible hiss from JM LAB Utopia tweeter at about two inches to my ear. |
There are electrical reasons which make a preamp the better choice for most amps out there. I will try to elaborate some other time. However for your cable question, it is worth trying xlrs to see what is going on. It sounds more likely, however, that your preamp is either introducing or amplifying a noise that is already there (rather than the noise being picked up by your cables.) Maybe try the preamp with other amps to see if it makes a difference. If the amp has gain control drop it and see if that helps. It is of course possible that if you are running very long rcas they pick up noise but that would have to be fairly long cable runs... |
Thank you Newbee, 4est and all others with comments. I guess if preamp was not necessary for sound quality, everyone would use a CDP with volume control. I have a couple of decent preamps but both introduce distortion when connected to the amps. I think my distortion problem started when I sold a pair of very good gold and silver RCA interconnects. I am not sure if I had the noise before and didn't notice it or the cables I am using now are not as good. A passive preamp may do the trick as has been mentioned before, but I don't want to buy a bunch of new equipment and still have the distortion noise. So that's why I am asking members to provide me with their experience. So far I have learned a lot. I would appreciate any info on "ground loop", etc. It may be very obvious to most but I am in the dark when it comes to complex trubleshooting. Keep those great comments coming. |
Anticipating the sonic results of driving amps direct with a CDP/DAC is really a crap shoot I think. I have a Wadia 302CDP. It is not bright tonally speaking but so far with the amps I have connected it to the tone was clinical and it benefited from using it with preamps (I've used several different preamps and the Wadia always benefited.) Perhaps it needed the edges filed off a tad by a pre-amp. I wanted it to be otherwise, but not to be so. I think if you must have balanced channels and/or XLR connectors, and your fussy about tone, you're going to need to get a pre-amp. Too bad you can't get demo on a CPD that you might favor. Actually, if you could figure out which CDP you would like, performance wise, you could buy one. Then if it didn't work you could add the appropriate pre-amp to solve your problem. FWIW. |
Espoverload,
I'd be curious to for you to report back to us any type of change you hear assuming to try a pair of the XLR interconnects. |
I doubt that the change from rca>xlr will help. I think that the pros of xlr are over hyped. In theory they are certainly better. In reality it may not make a bit of difference. In my system, the cable it's self makes more of a difference than the type of connections. YMMV |
Thank you for your suggestions. The major reason I'd like to use XLR connection is distortion. I hear a high frequency noise (distortion) from the mid-range and tweeters of the speakers. When I disconnect the RCA from preamp the noise disapears. I have tried everything and can't get rid of the distortion. The noise is not from the amps only when the RCA from pre is connected. So I was thinking if I could eliminate the preamp and go directly from source to the amp with XLR, I may be able to avoid the distortion. Otherwise, I am OK with the system's sound. |
I have tired various good passive preamps and have always found there sound to be lean compared to a traditional preamp. To each there own and that's just my opinion based upon my ears and system components, I don't want to offend those that prefer passive.
The Esoteric will work in your set up, and there are many other CDP's with volume controls that will also work.
The major point I want to make is some people will prefer the sound of the system using a CDP with volume control and others will prefer the sound using a traditional preamp.
The only way you will know for sure is to try it for yourself. |
It should work out ... on paper anyway.
The Plinius SA-100 amplifiers have 47 Kohm input impedance, which is theoretically a reasonable match for a passive (Lightspeed, Bent, etc) and hence a reasonable match for source direct.
Also, both the Arcam FMJ CD37 and the Esoteric SA50 have output impedance less than 100 ohms.
Given that your amplifier and your source (current and proposed) are theoretically well matched for a passive setup, you don't need to buy the Esoteric SA50 to accomplish this, a good passive would also do the trick.
However, you may want the Esoteric anyway. Either approach should work out in theory, but proof is in the listening.
If I may interject my own personal bias: with all of that solid state, I'd recommend a tube preamplifier, perhaps a Mapletree Line 2A SE for the budget conscious. |
I would go with a preamp and source.....I had the SA-50 in my system for a brief period, and have had the Arcam as well. My opinion is that I prefer the Arcam. I wouldn't put too much emphasize on having balanced/XLR connections either unless your cable lengths are more than 50 feet. If you only have one source, then no preamp is an option, but I would listen to what a decent preamp does for your system before buying a cd player based on it having a volume control. Besides, you may decide that you want to add a turntable in the future. |
