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Whatever1
02-23-2008, 01:30 PM
At what level (number) do you hear a noise (hum / hiss) coming out of your speakers? On the phono selection

At 29 - 30 I hear noise either with or without a phono hooked up.

Is this normal ?
robinje
02-23-2008, 02:48 PM
I hear no noise at even at max volume with my C220/MC275 combo unless I put my ear right up to the tweeter.
masterlu
02-23-2008, 02:59 PM
No noise regardless of source or pre-amp at 100% gain with all my Amps on.

I have to admit, it is very scary to do that though.
masterlu
02-23-2008, 03:00 PM
I'm sure RGPC units lowering the noise floor helps.
Whatever1
02-23-2008, 03:18 PM
Thanks everyone for your efforts.

At 29 / 30 I hear a noise... rushing sound with head phones it takes about a 55 / 60 level. Only on the phono input. Everything else is fine.

Any ideas ?
Tubes bad ?

I am going to call McIntosh on Monday for an answer.

Thanks again.
Victor
02-23-2008, 03:23 PM
This sounds like a normal condition. Keep in mind the phono section is 40 db louder than a line level input.

It is a while since I got rid of my C1000 but I think I had some noise from the tweeters at about 45-50.

Victor
chuckworkb
02-23-2008, 04:17 PM
No noise regardless of source or pre-amp at 100% gain with all my Amps on.

I have to admit, it is very scary to do that though.

It really is scary - I am always waiting for that LOUD buzz that freaks you out!

That would be a perfect time for someone to sneak up behind you and go BUZZZZ! Not!

Thankfully it never happened.
Gregory
02-24-2008, 04:38 AM
No noise regardless of source or pre-amp at 100% gain with all my Amps on. I have to admit, it is very scary to do that though.

Yeah.. same with the stove, and never look into a laser even if it's turned off. :banana:


-Gregory
Gregory
02-24-2008, 04:50 AM
This sounds like a normal condition. Keep in mind the phono section is 40 db louder than a line level input. It is a while since I got rid of my C1000 but I think I had some noise from the tweeters at about 45-50.

Victor

Keep in mind the surface noise and the dynamic range of vinyl. It's typical for system parameters of that era. Hmm.. will be doing more system tests today {and switching to phono}.

Haven't had the turntable out in a VERY long time. Unfortunately all my LPs have been left behind and are likely irretrievable.


-Gregory
Whatever1
02-24-2008, 07:39 AM
The rushing noise is heard no matter what is connected to the phono inputs and only on the phono input. With nothing playing. When an lp is on the rushing noise is louder than the surface noise from the lpbetween tracks.

Another forum member sugested the tubes might be failing. I will try some others this week.
C220MC275
02-24-2008, 09:57 AM
I hear no noise at even at max volume with my C220/MC275 combo unless I put my ear right up to the tweeter.

On my ESL, no noise at all, even at 100 !!
ron-c
02-24-2008, 07:58 PM
Phono noise should be tested with the phono input shorted. Just run an RCA cable from one side to the other.

Thanks,
Ron-C
markc2
02-25-2008, 11:36 AM
Phono noise should be tested with the phono input shorted. Just run an RCA cable from one side to the other.

Thanks,
Ron-C

I claim ignorance on this. Will look up on google. Make a loop ?

Thanks and sorry, haven't heard of this before.
ron-c
02-25-2008, 11:51 AM
Yep, make a loop!

Thanks,
Ron-C
Whatever1
02-27-2008, 02:18 PM
I replaced the original phono tubes with Sovtek's and the noise does not appear now until I turn the dial past 60. It is now liveable. This should not happen on a piece of gear priced as high as the McIntosh ( the unit is about 6 montrhs old... DON'T say one gets by because another issue with this unit is the knobs do not run true when you turn them they look out of round)

Other than that I guess you get what you pay for.
ron-c
02-27-2008, 06:12 PM
Did you have your dealer check the unit out?

Thanks,
Ron-C
Whatever1
02-27-2008, 06:34 PM
IT was brand new in the box.
Replacing the tubes moved the noise from 30 to 60. It made abig difference.
You would think for the price they are asking they would invest in a better tube, since all it took was someone on the forum to read and suggest it.

No I did not ask the dealer to check it out... If tubes would have not fixed it ... it would have gone back to the factory with me...
ron-c
02-27-2008, 06:37 PM
You could have asked your dealer to help with the tubes. That is not normal for the small tubes to fail but possible with tubes from China or Russia.

Thanks,
Ron-C
kurtbauer
02-28-2008, 12:05 AM
Shortly after I bought my C220, I noticed that the phono section was no longer silent. I took in to have my dealer take a look at it. It turned out to be an issue with the ground lug. Apparently, when the unit was built, the paint was not adequately scraped off at the ground lug. It was an easy fix and now it's totally quiet with original Winged Cs.

kb
Whatever1
02-28-2008, 04:42 AM
I mentioned to my dealer and McIntosh and they both suggested the tubes..
Whatever1
02-28-2008, 05:46 AM
Thanks for the suggestion... but this noise is there wheter anything is connectecd or not.

Shortly after I bought my C220, I noticed that the phono section was no longer silent. I took in to have my dealer take a look at it. It turned out to be an issue with the ground lug. Apparently, when the unit was built, the paint was not adequately scraped off at the ground lug. It was an easy fix and now it's totally quiet with original Winged Cs.

kb