AudioAficionado.org  

Go Back   AudioAficionado.org > AudioAficionado News > Technical Info & Troubleshooting

Technical Info & Troubleshooting Learn from the Pro's

Reply
 
Thread Tools Display Modes
  #1  
Old 07-17-2018, 04:51 AM
Berman002 Berman002 is offline
Junior Member
 
Join Date: Mar 2018
Posts: 22
Exclamation Speaker humming from a new Mcintosh MA252

Hi all, i just found that my ma252 having a humming sound from the speakers, not sure since day 1 or not.
humming sound when you put ur ear right next to the speakers.
both speaker and volume does not affect it.
can any of the expert help please?
I have tested all sort of things that i can test so far, nothing work.
tested:
no input.
different power cable,
different speakers,
different power point,
turn off all the power in the main except the audio power point.
test with 2 pin power plug

the humming still there as long as the speaker is connected and the amp is turned on. it's not affecting my listening, but still ignoring.....
may need to take back to Mc to service.......owned it for 3 months only from new....... any suggestion guys?
Reply With Quote
  #2  
Old 07-17-2018, 07:08 AM
bigblue bigblue is offline
Guest
 
Join Date: Feb 2012
Posts: 537
Default

What happens if you disconnect all other equipment from the 252?
Are they all connected to the same group of outlets or do you have a power strip/power conditioner?
Reply With Quote
  #3  
Old 07-19-2018, 04:16 AM
Berman002 Berman002 is offline
Junior Member
 
Join Date: Mar 2018
Posts: 22
Default

Quote:
Originally Posted by bigblue View Post
What happens if you disconnect all other equipment from the 252?
Are they all connected to the same group of outlets or do you have a power strip/power conditioner?
Hi there,
Yes i did remove all input, only power and speaker connected to the Amp MA252, speaker still hum, both channels and increase the vol doesn't make it louder.
all connected to the same power point.
i also tested plug in a headphone and play music to the headphone, the speaker connected to it still hum.
><
i also asking mcintoch, but no answer from them yet.
i can only hear the hum if i put my ear right in front of the speaker closely.
Reply With Quote
  #4  
Old 07-19-2018, 05:36 AM
tdelahanty's Avatar
tdelahanty tdelahanty is online now
Audio,Trains & Mustangs
 
Join Date: Feb 2010
Location: Indiana
Posts: 1,477
Default

If you can't hear it from your listening position, may be considered normal, remember this amp has a tube front end.
__________________
System: ML:5206,5302 Serafino's Nordost Lumin U1 RM15
Reply With Quote
  #5  
Old 07-19-2018, 06:51 AM
ps7256's Avatar
ps7256 ps7256 is offline
Member
 
Join Date: Nov 2014
Posts: 268
Default

Quote:
Originally Posted by Berman002 View Post
Hi there,

Yes i did remove all input, only power and speaker connected to the Amp MA252, speaker still hum, both channels and increase the vol doesn't make it louder.

all connected to the same power point.

i also tested plug in a headphone and play music to the headphone, the speaker connected to it still hum.

><

i also asking mcintoch, but no answer from them yet.

i can only hear the hum if i put my ear right in front of the speaker closely.


Are your interconnects and power chords running parallel? If not try running them over each other but elevated.
Reply With Quote
  #6  
Old 07-23-2018, 09:18 AM
Formerly YB-2's Avatar
Formerly YB-2 Formerly YB-2 is offline
Retired

 
Join Date: Jan 2010
Location: NJ Shore
Posts: 8,404
Default

You must be new to tubes. In gear with tubes you always roll in new tubes first to see if one of yours is noisy. You only need to purchase 1 or 2 new ones (our own vintage_tubes is a great source for reasonably priced & fully tested tubes - tell him your problem when you purchase). Replace one tube (or one per channel) to see if the one you took out might be the offender. If not, swap the tube in the next position. Tubes have AC on their filaments and can be noisy.
__________________
Glenn...
Clearaudio SM Pro Focal Bathys JLA 10" Dominion Kuzma Stabi S w/MC & MM Magnepan 1,7i McIntosh MA8950 Oppo 203 Roon Nucleus Rose Hifi RS150B Shunyata Gemini-4 Sony ST-A6B, TA-F6B & PS-X75 Sorane SA1.2 & TA-1L Stillpoints LP1v2 WW Pt, Au & Ag
Reply With Quote
  #7  
Old 07-26-2018, 08:00 AM
Berman002 Berman002 is offline
Junior Member
 
Join Date: Mar 2018
Posts: 22
Default

Quote:
Originally Posted by Formerly YB-2 View Post
You must be new to tubes. In gear with tubes you always roll in new tubes first to see if one of yours is noisy. You only need to purchase 1 or 2 new ones (our own vintage_tubes is a great source for reasonably priced & fully tested tubes - tell him your problem when you purchase). Replace one tube (or one per channel) to see if the one you took out might be the offender. If not, swap the tube in the next position. Tubes have AC on their filaments and can be noisy.
Yes i am new to tube, this is my first tube amp. but this ma252 amp and it's tube, both 3 months old only. noisy from both channel too.
anyway, i am going to buy 4 new tubes to test it.
I also got feedback from other ma252 owner, few of them having the same noisy when they put their ear in front of the speaker.
Thanks

Thanks
Reply With Quote
  #8  
Old 07-26-2018, 05:08 PM
62caddy's Avatar
62caddy 62caddy is offline
Member
 
Join Date: Apr 2012
Posts: 1,069
Default

What are the speakers you're using?
Reply With Quote
  #9  
Old 07-31-2018, 04:05 PM
Berman002 Berman002 is offline
Junior Member
 
Join Date: Mar 2018
Posts: 22
Default

Quote:
Originally Posted by 62caddy View Post
What are the speakers you're using?
KEF LS50 and Focal 906
Reply With Quote
  #10  
Old 09-11-2018, 10:23 PM
Ampteks's Avatar
Ampteks Ampteks is offline
Member
 
Join Date: Sep 2018
Location: Bay Area
Posts: 73
Default

I purchased a 252 and had the hum since day one, took it back a week later for a refund.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Audioaficionado.org tested by Norton Internet Security

All times are GMT -4. The time now is 09:51 AM.



Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
©Copyright 2009-2023 AudioAficionado.org.Privately owned, All Rights Reserved.
Audio Aficionado Sponsors
AudioAficionado Subscriber
AudioAficionado Subscriber
Inspire By Dennis Had
Inspire By Dennis Had
Harmonic Resolution Systems
Harmonic Resolution Systems
Wyred4Sound
Wyred4Sound
Dragonfire Acoustics
Dragonfire Acoustics
GIK Acoustics
GIK Acoustics
Esoteric
Esoteric
AC Infinity
AC Infinity
JL Audio
JL Audio
Add Powr
Add Powr
Accuphase - Soulution
Accuphase - Soulution
Audio by E
Audio by E
Canton
Canton
Bryston
Bryston
WireWorld Cables
WireWorld Cables
Stillpoints
Stillpoints
Bricasti Design
Bricasti Design
Furutech
Furutech
Shunyata Research
Shunyata Research
Legend Audio & Video
Legend Audio & Video