M200 transformer buzz - is it normal?

Well I decided to try out the M200's after all, and I noticed that the flat toroidal transformers in the amps continuously buzz a little when the units are powered on. The buzz does not come through the speakers, it is just coming from the transformers within the amps themselves. All the M200 units that I am auditioning are doing this.

It is not an extremely loud buzzing, instead it is just a light buzzing of the type you can hear in a quiet environment when you put your ear within a foot or so from the toroidal transformer itself. I tested to see if the buzz was dependent upon inputs or power conditioning, but the slight buzzing sound occurs both with and without inputs, and both with and without a power conditioner. So it is pretty much just the amps themselves.

What I am wondering is if any other owners of the M200's could please take a moment to also see if their M200 amps continuously buzz just a little bit (when powered on of course), just so that I can feel reassured to know whether or not this is normal for them to do it. Please try this, and post what you find?

Thanks in advance to everyone who helps me with this!

How long before you hear the buzz? Right out of the box? After warm up? I just plugged mine in at the kitchen counter right out of the box. Silent so far. Oops, on standby. Now on. No buzz. More Later.

Right out of the box.

Plugged in and "on" for 30 minutes. No buzz.

I have 3 of them and they are dead silent.

90 minutes total. dead silent. Better call Outlaw.

I got my threee and plugged them on with no other connections; I can hear a VERY SLIGHT buzz; I would think of it as a normal transformer sound....I need to get close (6 inches or less) to be able to hear it...

Anyway, let me know what you find out if you call Outlaw....

i don't own one,but there are alot of threads on the '200 forum' about this.seems to be some different thoughts on it.you aren't alone.

joe

I have 5 of them. Perfectly silent even with my ear right on top of them. I have read forum threads in which the AC line was responsible for some instability of the transformer and therefore, the buzz. others may know, because my are perfect. Good luck!

I guess what I need to ask is if hearing any hum at all (>0db @ 0m, I'll put my ear on the casing) is going to be an acceptable reason to exchange the amp for another. People talk about the great serivice from Outlaw, but are they gentle with raving fanatics?

Also, has anyone experiencing hum tried to tighten the transformer mount? And does Outlaw specify a rubber mount under the trans, and would adding one void the warranty?

I believe it is quite common for the transformer to hum very slightly, with your ear right on it. I would not accept any hum if it can be heard from several feet away in a quiet room. I encourage you to speak personally with the customer reps from Outlaw about this. They routinely bend over backwards for their customers. And they would know the incidence of any abnormal sounds.

Ran the monos all weekend. No buzz or hum. Even with ear to unit.

7 M200's, I don't hear any hum.

You should call Outlaw's customer service. They are extremely helpful. If there is something wrong with the amps (which seems unlikely as all three are exhibiting this issue), they will replace them. If the problem is coming from something else in your system, they will work with you to isolate and fix it.

I was never able to solve the transformer hum problem in the amps.

Outlaw was unable to help?

Was this more than one M200?

Your power line may be causing the buzzing. Some days my balanced power supply hums like crazy, other days - dead silent. It seems to be related to the "condition" of the power. IMO, The important thing is that you cannot hear it from your listening position. Not to say the transformers are perfect - if it is objectionably loud, I would pursue getting replacements from Outlaw.

I have 2 and never noticed a hum.