I am selling my existing system, or parts, to downsize and also I want something very "quiet". My existing system always had a slight buzz or hum when the amp was turned on. it's a conrad johnson mf2500a ss amp and a cj 18ls pre.
My old integrated krell kav300i did the same thing. It is so annoying. Why is this? Every place I've lived it's done this, and this time I used a monster hps7000 power conditioner. Do I have to live with this or is there something that is dead quiet when turned on? Looking at a musical fidelity integrated 3.5? Please help me.
Have you tried a cheater plug? It eliminates the ground loop hum. Most likely your problem. It's a 79cent fix.
It could very well be your ( crappy ) incoming power.. Also could be your Cable TV interfearing..?
On many occasions I've read that using a cheater plug is a potentially dangerous thing (fire hazard) therefore I've never done it except as a temporary test. Better to be safe than sorry.
Hi I would try the cheater plug which you can get from a Dollar Store 2 for $1. If that does not work I would tighten down the transformers on the chassis and place some
neat dampening blocks under it. Check your polarity to make sure it's correct. Some people will reverse the wall plug and get great results. Some people have problems with Line Conditioners too. Take it out of the loop. Sometimes your tubes may be weak and need replacing or rebiasing. Just some thoughts! Also check the tubes in the preamp. With the cover off and the volume cracked open
tap the tubes with a pencil eraser. If you hear noise coming through your speakers turn off everything and unplug the gear and clean the tube pens with an exacto knife then isopropyl alcohol and treat it with some Pro Gold, etc. If one those don't help hmmmmmm!!!!
Please see the following excellent reference:

As you'll see, interconnect cables are usually key factors in how hum/buzz is introduced into a system. They should be kept as short as possible, and should be chosen to provide low shield resistance (although unfortunately that is often not specified, and trial and error among different cables may be the only way to tell).

-- Al
I had a constant buzz through my system when inputing the cable box...... Satellite box never made a buzz but the cable box created a loop..... now I keep video and music separated...... 2 ch. is only music...... No more buzz of any kind.....
I don`t care what you do to it the CJ MF2500A is always going to hums.It was made that way.I sent the one I had back CJ and they said nothing could be done about it.SORRY
Thanks guys for your input.
By the way, what is a cheater plug? What does it look like?
Also, any suggestions on what integrateds might be really "quiet"?
Both my cj amp and pre were solid state.
I have Kef 205 reference and only do redbooks cds.
Any suggestions would be appreciated.
My Pioneer 51FD Blu-Ray player makes a "whooshing" noise when I play DTS HD-Master music disks (Dolby True-HD, DVD and Blu-ray are very quiet).
My Toshiba A35 HD player is just plain NOISEY! (cheap casework)

I've purchased a four-bay equipment rack with a plexiglass "front door" to try and block the noise.

I'm putting the whole thing together tomorrow and will see if it works out.
The ground loop theory is your best lead to follow. All of your components should ground at one location in the wall, and only one component with a ground plug, float everything else with a cheater plug. Be sure your AC receptacle has good spring tension. Many times the tension is so bad that the plug nearly falls off the that is a fire hazard. Get a Hubbell or hosp. grade AC outlet and this is contact. Jallen
A cheater plug is accepts a 3 prong (w ground pin) but has only 2 prongs out.
01-28-09: Jdnamn97
Thanks guys for your input.
By the way, what is a cheater plug? What does it look like?


If you use this type of adapter make sure you insulate the ground strap of the adapter from touching the receptacle cover plate holding trim screw. (The trim screw is bonded to the equipment ground strap of the receptacle.)

Safety note:
The adapter is not UL approved to be used as a ground cheater.
Is the hum coming out of the speakers while the system is turned on or is it coming form the amp when it is turned on? The cj mf series does have a slight transformer hum when turned on. I owned one and it was never bothersome..........couldn't hear it from my listening chair. If the hum is coming from your speakers while the system is powered up then try lifting the ground with a cheater plug as suggested above.