New MA252 Integrated Amp

[Route 66]

EDIT:

Mine has the faintest hiss or hum that doesn't change at all when I adjust the volume up and down. I don't know if yours has more than that or not, but I am able to hear something. There's no way I can hear it unless I have my ear right next to the tweeter though.


Has yours done it from day 1?

Is the humming coming from both channels?

Do you have any other 12AX7 or 12AT7 tubes you can swap the originals out with?

Is it a 60 cycle hum, or more of a hissing sound?

Are you able to feel any vibration when you place your fingers on the woofer cone?

You may want to test it at a friends house and see if you can still hear it there.

[Formerly YB-2]

Yep......... order a new set of tested & matched tubes from our own AAf member, vintage_tube, and am guessing your hum will be gone.

[JBT]

Kevin Deal of Upscale Audio in California burns in and tests all the tubes they sell so you know your getting a good product. Been dealing with him for years!

[Route 66]

Originally Posted by JBT

Kevin Deal of Upscale Audio in California burns in and tests all the tubes they sell so you know your getting a good product. Been dealing with him for years!

He's a great guy to talk to too and his store is unbelievable!

[stereo_5]

I got burned twice on NOS tubes from uncle Kevvy at Upscale. I purchased 2 NOS Mullard CV4003 tubes and one went microphonic within 6 months. Bought 2 pairs of NOS Mullard 12au7 tubes and one tube in each channel developed a loud hiss within 6 months. This was in 2 different systems.

[JBT]

Tubes aren''t perfect, but I've been dealing with him for close to 20 years and have had nothing but good results.

[Formerly YB-2]

Originally Posted by stereo_5

I got burned twice on NOS tubes from uncle Kevvy at Upscale. I purchased 2 NOS Mullard CV4003 tubes and one went microphonic within 6 months. Bought 2 pairs of NOS Mullard 12au7 tubes and one tube in each channel developed a loud hiss within 6 months. This was in 2 different systems.

Will no longer deal with Kevin for similar reasons. Once burned, twice shy and all that.

[Berman002]

Originally Posted by Route 66

EDIT:

Mine has the faintest hiss or hum that doesn't change at all when I adjust the volume up and down. I don't know if yours has more than that or not, but I am able to hear something. There's no way I can hear it unless I have my ear right next to the tweeter though.


Has yours done it from day 1?

Is the humming coming from both channels?

Do you have any other 12AX7 or 12AT7 tubes you can swap the originals out with?

Is it a 60 cycle hum, or more of a hissing sound?

Are you able to feel any vibration when you place your fingers on the woofer cone?

You may want to test it at a friends house and see if you can still hear it there.

I guess, mine does the same as your, i can't hear it unless i put my ears right in front of the tweeter or woofer.

Turn up the vol doesn't get it louder. it's on both channels.

So i guess it does to most of the MA252? consider it to be normal? i do not have other tubes....

i just test it with a headphone plugin and playing music, the hum or hiss still there to both speakers.

This is what the Mcintosh quality? or i am just being picky?

[MORTIS]

Originally Posted by Route 66

EDIT:

Mine has the faintest hiss or hum that doesn't change at all when I adjust the volume up and down. There's no way I can hear it unless I have my ear right next to the tweeter though.

Originally Posted by Berman002

I guess, mine does the same as your, i can't hear it unless i put my ears right in front of the tweeter or woofer.

Both your descriptions sound to be normal. I've never owned a system that didn't put out at least a little hiss when I put my ear up to the tweeter. The amount of hiss is mostly dependent on the efficiency of your speakers.

[PeterMusic]

Originally Posted by Berman002

I guess, mine does the same as your, i can't hear it unless i put my ears right in front of the tweeter or woofer.

Turn up the vol doesn't get it louder. it's on both channels.

So i guess it does to most of the MA252? consider it to be normal? i do not have other tubes....

i just test it with a headphone plugin and playing music, the hum or hiss still there to both speakers.

This is what the Mcintosh quality? or i am just being picky?

Brownbear had great advice a couple of days ago. Is there a reason (or maybe I missed it?) why you have not called your dealer or taken it in?