[Nick B]

I picked up some used D200's on Agon and have had them for a few days. Supposedly, they had only 50 hours on them and I have no reason not to believe the seller. They are cosmetically perfect and Dusty verified about how many units were built since  those serial numbers. Initial impressions are good. On well recorded music, they sound excellent. But on mid quality recordings, which I have a lot of, there is quite an edge. In idle, there is a slight buzz from the 7" Focals and a hiss from the Focal Audiom TD 5 tweeters. My previous amp was dead quiet. Now, when music starts to play, there is a slight chugging?, sputtering? sound that eminates from the right tweeter. Never heard that before. These noises are subtle, with my ear up against the speakers, but I wonder if that translates into some of the harshness I am hearing on my mid quality recordings. I will be putting lots of hours into break in.  I'm also trying to check line noise problems like dimmers, appliances etc, but so far, have found nothing. My previous amp was  a ss class A/B design. Any comments are much appreciated.

[Nick B]

I should have mentioned that I'm going straight into the D200's with my Aberdeen SB2 and his PS. No dac in between and no noise previously going into my Metaxis ss amp.
I will switch IC's when I get a second wind. Squeezing between my huge cabinet and the wall is really tough. That's why I dislike auditioning stuff.

[CIAudio]

To see if the amplifier is causing the noise, you can do the following:
Take a cheap RCA cable, cut in half and tie the two conductors together creating a short across the amplifiers input. This will tell you if the noise is coming from the amplifier itself.

Do you know the gain of the models you purchased? If the new amps have higher gain than your previous amp, you will have higher noise at the same volume position. D-200's are very revealing of everything in the chain, so it could be you're now able to hear things that weren't audible with your previous amplifier.

[Nick B]

Gain is 26db. I will call you if I can't figure it out. These noises are slight and the rt channel tweeter definitely sounds different than the next. 

[HumanMedia]

Gain is 26db. I will call you if I can't figure it out. These noises are slight and the rt channel tweeter definitely sounds different than the next. 

I had a similar problem with mine.  In one channel more than the other also.

It turned out to be a combination of a differential on the ground interconnect wire between the poweramps and the preamp (or something upstream) and the fine 28awg interconnect I was using which created some sort of feedback loop problem.

Different interconnect (thicker gauge) OR adding a chassis ground to the preamp fixed it.

[Nick B]

Thanks for the information, HM. I will work on this and try and get it resolved on Monday.

[richidoo]

Was your previous amp integrated by chance? I had similar problem when I was demoing a pair of Nuforce9SE and running SB3 direct to them. My amp is a Cary integrated which I use the volume control on it with the SB maxed. With the monoblocks I could not do that and used the internal SB volume control. The SB has good S/N only when software volume is cranked. If you turn down the analog output in software as you will HAVE to do in front of the D200s  then only the digital signal is "attenuated" but the real noise in the SB analog section is not affected, thus destroying S/N, and yes, it is very audible, espcially in right channel where the display noise affects analog output.  SB3 especially has a problem with noise generated by the plasma display. Not a problem when volume is maxed, and display dimmed or delayed shut off. This made me crazy for a few days while I tested every other component. Maybe SB2 has a plasma display also? I know SB2 & 3 circuits are similar in other respects.
Rich

[CIAudio]

I spoke to the customer and he had traced the noise to another component (I forget which one).
I believe it was a passive filter box connected to the CD player output. Maybe he can chime in on this.

He reloaded the SB software and that fixed the volume issue.

[Nick B]

The problem has been resolved. I had hooked up a "gizmo"....an analog\digital enhancer called the ADE 24 from Margules Audio (Mexico) . I bought the thing at CES a couple of years ago and just starting using it recently, with good results, on my prior solid state amp. Forgot the ADE 24 was active in the system. That was the source of my noise. Why a simple component like that would generate noise with the D200's, I have no idea. I sent an email to Margules, but they never answered.    There is a very slight hiss from the tweeter, but this is very close up only and I consider this normal. I will mention there was a disparity on the heat of the D200's. One chassis was a bit hotter than the other. My Agon seller paid for the shipping to Dusty and he adjusted the deatime setting? and promptly returned it as it was within warranty. Great service. So now the D200's have maybe 130+ hours on them and really sound great. It is the best sound I have had so far. Very revealing, yet non-fatiguing sound. Great midrange. The build quality is very good and I can move the little monos without screwing up my back. I'm a happy camper 

[Charles Calkins]

Nick B:
 Welcome to the D-200 fan club.

                    Cheers
                  Charlie

[Nick B]

Thanks, Charlie. Glad to be a member.