Manley Vari Mu - sound coming from the unit

[alloysound]

OK this is freaking me out - with music playing and the monitors cut, I hear music coming from my Vari Mu... like there's a little set of headphones in there somewhere....

Yes, I've checked to be sure there are no headphones lying around leaking a bit of sound.

Should I be concerned or possibly have my head examined??

[matucha]

mine does that too...

[RTR]

well what do you want for $4500.00? Make sure you are using $2000.00 cables with it !

[Matt Syson]

Hi
Capacitors, Valves and transformers CAN emit sound although strictly speaking they shouldn't to any significant level.
If you were interested you could CAREFULLY run it with the top off and gently press various components with the rubber eraser on a pencil or other firm insulating 'probe' and try to derermine what component is producing the sound.
DO NOT TOUCH anything m,etallic with your fingers or probe other than the transformers as there is a high risk of electric shock or possible heat burns from the valves.
Matt S

[TRJanuary]

on mine, its the transformers.

[EveAnna Manley]

It is the transformers. It is normal.

[matucha]

I thought it's the tubes, but never really cared, because of results

[alloysound]

Thanks all - though I may still be going crazy for other reasons...



Would better cabling diminish or eliminate that? It doesn't bother me - just want to be sure I'm not stressing any components.

[[silent:arts]]

Originally Posted by alloysound

...Would better cabling diminish or eliminate that?

no.

[Matt Syson]

Hi
How loud is it?
I am happy with the concept of a power transformer emitting noise if it is handling more than say 50 watts but for 'line level' it strikes me as a bit odd. It can only produce 'sound' (vibrating the air directly or indirectly) if something is moving, be it windings, laminations or something nearby being attracted by the varying magnetic field. Vibrations of this sort add to the 'mojo' of these things. Normally you do not want anything to move because it is varying the characteristics of the transformer.
Matt S

[matucha]

Originally Posted by Matt Syson

Hi
How loud is it?
I am happy with the concept of a power transformer emitting noise if it is handling more than say 50 watts but for 'line level' it strikes me as a bit odd. It can only produce 'sound' (vibrating the air directly or indirectly) if something is moving, be it windings, laminations or something nearby being attracted by the varying magnetic field. Vibrations of this sort add to the 'mojo' of these things. Normally you do not want anything to move because it is varying the characteristics of the transformer.
Matt S

it is as if someone left earbuds playing softly in the box

I was quite surprised when I got my VM, because none of other boxes I have does that (gyraf eq, tab funkenwerk pre, manley pre...). But it could pass sound "transparently" so I thought it is fine.

[EveAnna Manley]

It's an extra feature we offer: the mechanical acoustical monitor output.

[matucha]

simply the best

[dale116dot7]

The sidechain transformer in my DIY'ed 660-ish compressor does that, and the audio from that transformer is distorted, too - it sounds kinda like it looks on the 'scope, the worst case of crossover distortion that I've ever seen or heard. That's because there is a separate threshold and ratio (the AC and DC threshold) settings, and the DC threshold generates a dead zone at zero-cross that looks just like an extreme case of crossover distortion. In a Fairchild design, that's ok because the sidechain amp is only used for that - the audio coming out is not meant to be listened to.

There's lots of signal in transformers in a tube comp - it not only sends the output back to some whimpy solid-state console (though most tube comps are capable of driving a 600 ohm terminated cable to levels in the +25 or +30 dBm range), but the transformers also need to deal with the power to charge the sidechain attack/decay capacitor. I don't know how the Manley is designed inside, but the Fairchild (and the Gates Sta-Level) uses something like a ten watt or so power amp for its sidechain, and even an Altec has a couple watts available. The Gates share the sidechain and output power amp - the sidechain comes off the primary of the output transformer, the Fairchild has a separate sidechain amp. That's enough power to make some audible transformer noise.

-Dale

[matucha]

Well it [VM] generates "extreme" amount of heat, so I guess it moves more than electron or two.

[Marogru]

Yes, my Vari Mu is a perfect coffe heater, batter then those usb heating pads.
Just put your cup on the grill and mix

[Rick Sutton]

I only get concerned when my gear starts singing a different tune than what I am running through it.

[Nolet]

My Great River preamp does that too! I also started a thread about it here! I love it!

[nbrecording]

I have a Neve 33609 that does it too............