Leben CS600 Owners - Help


I have recently become a happy owner of CS600. I will write another post about my overall impression of its sound, but there is one minor issue. There is a very subtle hum coming out of the transformer. It does not interfere with music listening, but I can still hear it from the listening position when the music stops and the room is quiet without AC or other ambient noise. Using the Decibel app on iPhone, I tried to measure the sound level. It is not detectable from the listening position. When I place the iPhone just an inch above the top grill of the amp, the sound level goes up from 55 dB (ambient level) to about 68-9 dB. Should I call it 15 dB increase or just a noise at 69dB?

I am just wondering if this is an expected level of transformer hum for a normal CS600. Can any owner of CS600 try it for yourself and confirm? Much appreciated.
hgim
That's a story with a happy ending. I've heard the 30.1 and would own them had they been released before I purchased the C7ES3's.

My integrated is a Rogue Cronus Magnum which I love but sometimes feel I'm missing out on some detail. I've done some minor tube rolling but I'm losing interest fast. I'm considering either a solid state integrated (Hegel possibly) or KT120's for the Rogue. I'm just not sure what I'll get out of KT120's besides more power.
Hgim,

I got my CS600 a month ago and have the same hum sound as you described. Thought it was defective and took it to the dealer. His demo unit also have the same hum sound. He told me that it was normal. On mine, I can only hear it when standing or sitting next to it when music is not playing.
As for speakers, I'm also thinking of getting the M30.1. Right now, my CS600 is hooked up to a pair SF Auditors. The combination sound very nice but I always hear or read about the Leben + Harbeth combination. In a few weeks, I'm going to demo the M30.1 to see if they are any better than the SF Auditors.
Glad it worked out.
I love the CS600. I had transformer hum with a previous amp and it was a deal breaker for me.
I've been thinking about trying the Harbeth 30.1.
Heard them with the Red Wine audio amp at the NY show and the sound was beautiful.
Still using the focal electra's and they sound great with the Leben too.
Listening as I write this. Tomasz Stanko Quartet, Matka Joanna on ECM.... warm and crisp at the same time.
Thank you all for the kind words and further input.

Xmuavah, I suggest that you try to place CS600 on a sturdy platform, either directly on the floor or an amp stand. I suspect that the hum will be reduced.

Oddmorning, I'm a big fan of ECM label. The M30.1/CS600 combo made some obscure (and somewhat uninteresting) ECM music come alive by rendering the live studio in front of me.

Donjr, please don't go to that route (IMHO). I heard good words about Rogue Cronus Magnum, which I'm sure is a fine product, but there's so much you can expect for the budget. I'm an expat and in my US home I have Audible Illusions M3A -> CJ MV-60 -> Proac 2.5. The system is comparable to my new system in retail price (at the time), but I never got this kind of sound. I also seriously thought about Hegel H300 as a second amp in case I need more bass and power, but I completely changed my mind now. I'm still interested in Hegel H25 DAC though.
Hgim,
Thanks for the suggestion on the hum noise. What tubes are you using in your CS600 and why? Have you try any other speakers before buying the M30.1? Thank you in advance.