Speaker noise with C45

Hi All,

My audio system consist of following:
- McIntosh D100 DAC (Connected via RCA to C45)
- McIntosh C45 preamp with Tuner (Connected via XLR to MC352)
- McIntosh MC352 Amp
- JL e112 sub (Connected via RCA to C45)

I read lots of C45/owner say their preamp is "dead quiet", my C45 is not! If I put my ear next to speaker I hear shhhh, white / parasite noise.

I removed C45 from the system and used D100 as a Preamp/DAC and my speaker were "dead silent" ! Inserted C45 back into my audio system and speaker noise was back. I suppose I can conclude the noise comes from the C45.

Is there any way to remove the noise coming from C45 ?

Thank you,
AJ

What source do you have selected in the C45 when you hear the noise?

Thanks,
Ron-C

D100 is digital amp. It will take out any other moise in your system if you have a 60 Hz hum. If you have a coax from cable TV to another componet it may introduce that hum. If it isAmp hisfrompreamp that is another matter. what is the S/Nration of C-45 versus D100?

It's not a hum, more a shhh, white noise. I only hear the noise when nothing is playing, maybe "some" white noise is normal?
Disconnected everything except Amp from speakers and I get an ever-slight white noise coming out or tweeters.
When c45 is connected I get a "louder" white noise coming out of speakers. By "louder", I mean it can only be heard if I stick my ear roughly 1 foot or closer from speakers.
Just acquired c2300, which I should receive sometime next week. Will test out difference between both preamps.
Thank you for your input.
AJ

Velocity: I did not understand your question, "What is the S/Nration of C45 vs D100?"
Thx... AJ

I got auto corrected Signal to noise ratio. The higher is the quieter preamp. Anything over 90 dB is good over 110 is phenomenal. Noise will increase with preamp gain.

I think what Ron is getting at is that the phono section of the C45 has a lot more gain than any of the other inputs. On the other hand, if you've selected the CD input and hear the noise you describe, it may be that the C45 is slightly noisier than the D100.

S/N specs are as follows:

C45 phono - 86dB
C45 high level - 96dB
D100 - 110dB

There's the difference.

Keep in mind that some noise with your ear next to the speakers is just normal. That's not an indication of a problem.

Losts to learn in HIFI !
These are the infirmation I gathered which confirm Damacman information:
C45: Signal to noise ratio: 86dB (MM), 96dB (line)
D100: Signal to noise ratio: 110dB
C2300: Signal to noise ratio: 80dB (MC), 80dB (MM), 93dB (line)
Interesting c2300 is lower than older c45
For now, I only stream via Spdif to D100 -> C45 using Spotify premium, Tidal HIFI and NAS via USB. Will swap C45 for c2300 next week.
Don't get me wrong, I love my McInrosh system, it sounds 10000% better than my previous audio system. Since sound is clearer I am getting pickier and learning what is normal and what is not.
Love McIntosh sound !!!
Thank you all... Enjoy 4th weekend!
AJ

Can you hear the pre-amp noise when seated in your listening position?

What is the sensitivity of your speakers? Very sensitive speakers can reveal the noise floor in a system...

Kev... I can only hear noise if I put my ear 1 foot away or closer from speaker ... Otherwise from seating/listening position I do not. To answer your question and I don't really know what it really means at this point:
Sensitivity for Martin Logan Motion 60XT
94 dB @ 2.83 volts/meter
Audiokarma is a Great website/ great people to learn from !
Thx... AJ

ajdo said:

Kev... I can only hear noise if I put my ear 1 foot away or closer from speaker ... Otherwise from seating/listening position I do not. To answer your question and I don't really know what it really means at this point:
Sensitivity for Martin Logan Motion 60XT
94 dB @ 2.83 volts/meter
Audiokarma is a Great website/ great people to learn from !
Thx... AJ

Click to expand...

AJ: hearing that shhh/white noise-type sound within a foot of the speaker is fairly normal, at least with all the speakers I've owned while no source is playing and in a quiet room. The 94db of any speaker would be considered on the high side of sensitivity; and the higher the sensitivity, the more likely you'll hear any system noise.

Every component will have a noise floor. C45 is pretty good and the new models that use a split chassis, with all of the digital + power supply on one level and the analog circuitry separated will be best. C2500, C48 and C50 are made this way so they have -100dB SN ratio.
These new preamps also use R-Core power transformers which helps. Each 3dB is a doubling of noise. 30 years ago -80dB was a superb S/N ratio. Tubes will always have thermal noise since that is how tubes work. If the preamp is a two chassis design and fully balanced, like C500 and C1000 this will improve S/N even further but at a cost.
If you have be next to the speaker to hear background hiss, then just go sit down and enjoy the music.

thanks,
Ron-C

First set all tone controls in C45 to flat. Then check if hiss you hear is dependent on volume level.

In the past, I heard lots of McIntosh owner and other brands, saying/writing how dead quiet their system was, so I was just making sure there was no issue with my system; going through my learning curve.
Thank you all for sharing your knowledge which will allow me next time I make a purchase to scrutinize and understand better the specs sheet. Most importantly, simply appreciate the sound of my current McIntosh audio system.
P1: Yes, hiss is dependent on volume level. But from my seating listening position, switching C45 to an unused input, I have to turn the volume to 100% to start hearing the hiss/white noise coming out of my speaker.
Again, thank you all ! Glad I joined this forum...
AJ

ajdo said:

In the past, I heard lots of McIntosh owner and other brands, saying/writing how dead quiet their system was, so I was just making sure there was no issue with my system; going through my learning curve.
Thank you all for sharing your knowledge which will allow me next time I make a purchase to scrutinize and understand better the specs sheet. Most importantly, simply appreciate the sound of my current McIntosh audio system.
P1: Yes, hiss is dependent on volume level. But from my seating listening position, switching C45 to an unused input, I have to turn the volume to 100% to start hearing the hiss/white noise coming out of my speaker.
Again, thank you all ! Glad I joined this forum...
AJ

Click to expand...

Any system makes noise when you put your ear up to a speaker. Normally you should never hear hiss from listener position. Also no hiss should be heard more than feet away from speaker at volume set to a normal listening level.

ajdo said:

In the past, I heard lots of McIntosh owner and other brands, saying/writing how dead quiet their system was, so I was just making sure there was no issue with my system; going through my learning curve.
Thank you all for sharing your knowledge which will allow me next time I make a purchase to scrutinize and understand better the specs sheet. Most importantly, simply appreciate the sound of my current McIntosh audio system.
P1: Yes, hiss is dependent on volume level. But from my seating listening position, switching C45 to an unused input, I have to turn the volume to 100% to start hearing the hiss/white noise coming out of my speaker.
Again, thank you all ! Glad I joined this forum...
AJ

Click to expand...

Yeah this is not the way to judge any component and really it's showing more of IC, ACP and open RCA jacks picking up RFI in the air than noise in your C48.

If you want to reduce noise in the whole system start paying atenton to Radio Frequency Interference (RFI) It can come from eletrical towers, your WiFi, the house AC, Home appliances and the system as a whole.

Think of it this way electricity is in the air and all the wiring and anything metel like the boxes, RCA jacks, AC cords Speaker wires and so forth are antenas. All these antenas need quality shielding and proper routing so they are not antenas picking up RFI.


When hooking up your system get all the AC pluged in first keeping a short direct rout to components. Don't bunch up AC cords behind the the components get them away from all those RCA jacks and IC you have. You can tye these togther out of the way.

Interconects can be instaled now and try to keep them away from the AC lines. Don't bunch these up eather let them hang loose for each component, I hook up my turntable last as I have stand alone Phono Preamps that carry a higher gain though the cables to the preamp.

Last run the Speaker wires trying not to cross over all the other cabeling.

427: Thank you for your input. Have re-routed all my wires this weekend. Free solutions are definitely worth trying to reduce possible noise.
AJ

for_p1 said:

Any system makes noise when you put your ear up to a speaker.

Click to expand...

If you hear noise then you have a deficient audio system.