Lamm LL2.1 Deluxe "DC Offset"?


Hi there,

Is there anybody who has a deep experiences with high fluctuated "DC offset" in Lamm LL2.1 Deluxe PreAmp?.

My Lamm LL2.1 Deluxe Preamp shows a highly fluctuated DC reading that reaching +-200mV even more. Last night measurement showed a flucuated reading and reached +-300mV.

A three weeks continuous observation shows that the preamp DC fluctuation seems higly affected by the swing/fluctuation of AC Volatage,day time and night time. I can see that even as small as 0.3V AC voltage abrupt swing will directly generate significant DC offset in the LL2.1.

Your sharing experience and advices are higly appreciated.
gr-gin
I own Lamm LL2.1 (and owned LL2, L2R) and tried all of them with a lot of different amps. I never had or had such a woofer movement. You can get in contact with the manufacturer, probably there is something with it, who knows...but it is not common imo.
Dear Chayro and Syntax,

Many thanks for your advice.

I did contact the dealer as well as the manufacturer. It seem they in difficulties to find out what is realy happen to the unit itself.

I onced sent it to the dealer, they hooked it to their hybrid Audio Research amp and found that things seem just fine. But when I brought it back home, the problem remain occurs. Then I brought the unit again to the dealer when we finally confirmed that there is a Highly fluctuated DC Offset. Not as high as in my home AC, but that might be caused of their using power conditioner in their system.

They suspecting a leakage in the output capacitors, but considering of its sensitifity to the AC fluctuation I suspect a more serious problem in the upstream side of the circuitry, could be in the power system.

The manufacturer strongly suggested me to manage it through the dealer. While I am away, I did text the dealer to check the progress of their observation but no reply. I am affraid they in trouble of finding the real caused of the problem.

Perhaps I need to find the way to manage and repair it by myself, but need in advance advices before start working on it.
That's crazy. Anything purchased new from a dealer should be delivered in perfect working condition. If they can't resolve the problem, get something else. Jesus, why would you bother buying new from a dealer except for the support? Otherwise, you may as well buy used and pay half the price.
Hi Chayro,

Many thanks for your empathy.

It's a hard long story. Iam on the way back to my home-country and curious to check the dealer, again, what is the story, they have been silent since I drop the unit for the second time. Learning from the 2 months strugle of getting their admittance that there is a real serious problem, I have to manage myself to get ready of being disappointed.

Contacting the manufacturer did not give any help, they shift it to the dealer. Seem they rely to the dealer's technician which I doubtly can realy manage in finding the real problem on it.

I agree with Syntax, it is something not common. The issue and challange then is how to find the root of the problem, and this should be managed by the manufacturer who realy know the design and topology of the unit, not leave it to the free-lancer technician.
Vladimir himself should take this unit back!One of the following should be done.
Repair it properly.
Replace it with a new unit
Refund your money in full.
This is a high cost component purchased new with a warranty. Something isn`t right with the Manfactuer`s response.