McCormack + B&K, initial impressions...

[SteelerFan]

I picked up a B&K 200.5 from the dealer last Sunday and yesterday the new McCormack MAP-1 pre-amp I bought from someone on Audiogon arrived. Last night I hooked up everything in 2 channel mode until my 5.1 cables come in from bluejeans.com.

As far as the sound my first impression is very detailed but not overly bright like the sound I used to get from my Yamaha. Pretty much where I wanted to be.

For those who are not famaliar with the MAP-1, it's an analog pre-amp but it has two 5.1 inputs and a 5.1 output. It does no Dolby/DTS decoding on it's own, you must depend on the DVD player for that. Ever since I first ran across it I've thought it might be the pre-amp for me since I'm not a really big movie guy. I watch them but don't collect them, once I've seen it I seldom feel the need to see it again. What I love are concert DVD's, I watch them over and over. With the MAP-1 I feel I'm guaranteed the finest in sound.

It does have one surround mode they call ARM that can be used for 2ch sources and it works very well. I've had Chris Isaak's "San Francisco Days" playing on it all day burning everything in.

The bad news is I've got a hum just like I did with the NAD stuff I had awhile back. I'm not blaming the McCormack or B&K amp, it has to be something else that's wrong. It's coming from all speakers except the center. The surrounds are worse than the mains. I'll keep working on it, or maybe I'll eventually get used to it.

I'll report back when I get it hooked up in 5.1.

[chuckears]

I'm not saying the MAP-1 pre is the culprit, but all three of the McCormack amplifiers I have owned seem to pass on a hum in my system that I can never totally get rid of. Having said that, they are also the finest amplifier(s) for my Fortes that I have ever heard.

[SteelerFan]

I really don't think it's the McCormack that's causing the hum. I tried the NAD S170 and S250 amp along with the Cary HTA2 amp and had the hum with both the NAD and Cary. The dealer sent me another NAD amp that they had worked on the grounding of and tested and I still had the hum.

I was ready to blame the NAD pre-amp when I tried using my DSP-A1000 as just an amp and there was no hum.

I don't think it's the B&K amp either that is responsible. The Yamaha has a skinny, 2 prong power cord that is permanently mounted to it, I'm wondering if that may have something to do with it. But I did try cheater plugs on the NAD stuff and still had the hum. I haven't yet tried them with the McCormack and B&K but I don't think it will work.

I think the problem may lie in the cabling. I've been careful not to cross them with any power cords but I still think they are picking up the noise somehow. When I get the new ones from bluejeans I'll swap them for the Cobalts I'm using now and see what that does.

[cjgeraci]

Happy to hear that this preamp/amp combo sounds good. Sorry to hear about the latest hum stuff. Given that this is your second go around on this issue, you may be on to something as far as the cables are concerned. As you know, my recent switch from pretty decent interconnects to custom, extra shielded jobs eliminated 99% of my hum issues.

Here's raising a glass to the bluejeans cables solving your hum.

One other thought. You said that your RC-7 does not have the hum, yet your RF-7s and surrounds do? Something strikes me as strange about that, especially since I presume you are running the same brand/model of interconnects for all speakers. When I had hum problems, the strength of the hum was similar through all speakers on a particular amp and only varied in strength between amps. Your RC-7 is supersensitive and should reflect the hum. Maybe this oddity could assist the veterans out there in helping to troubleshoot your hum in case the new cables do not solve the problem. Anyone have any thoughts?

Carl.

[SteelerFan]

It is odd as far as the center not humming, but now that I think back I think I got the center to stop humming with the NAD also. As I remember I was playing around with the cables and it just quit, couldn't figure out how I did it.

The center does have sort of a high pitched whine the other speakers don't have but it isn't noticeable unless I put my ear right up yo it.

Carl, I'm going to re-read your post on how how you solved your hum problems and see if any of it works for me. I may need to find a custom cable maker myself.

If anyone else has any ideas, please sing out.

[SteelerFan]

I have found one thing about the McCormack pre-amp I don't care for, the remote. It's tiny for one thing, 6 1/2 inches long by 1 3/8 inches wide by 3/8 inches deep. If that falls between the sofa cushions I'll never find it.

What's worse is there is no power up button on the remote! It has to be turned on by the power button on the faceplate. I was going to set up the trigger for my amplifier but what would be the point? I may as well push both buttons while I'm up. Oh well, nothing's perfect. I love the sound and the simplicity and can't wait to get the multi-channel analog set up.

[cjgeraci]

John:

Disconnect all of your interconnects from your amp. Leave the speakers still connected. Turn on the amp. Do you get a hum? If no hum, that should eliminate the amp as the source of the hum.

That would leave the interconnects, pre/pro and power coming in to the pre/pro.

Carl.

[cjgeraci]

Double post - me bad.

Carl.