Problems with my Berning ZH270

I'm going to guess that your tonal balance problem is a lack of bottom end, which shows up as brightness. Addressing this situation may well involve radically re-arranging your room. To test out this hypothesis without moving stuff all around, try listening up against the rear wall (the one behind your listening position), and see if the tonal balance doesn't improve when you do so.

The Nordost SPM can be a bit tipped-up in balance also; you might try Audience Au-24 instead (disclaimer - I peddle Audience).

The Merlins are superb loudspeakers and worth all the trouble they will put you through as you bring the rest of your system into focus around them.

Merlins ar bright bright bright.

Many have said the same Marakanetz, myself included when I first got my pair over 3 years ago. On the other hand many have ended up eating those words for lunch when they heard these speakers properly set-up. I know of several first hand. They are very intolerant of poor system matching, no forgiveness at all. As Duke notes, they can be a hassle but when things come together they are about as good as it gets in this hobby. This is the reason Bobby P. spends so much time with his customers, to help and advise them in this very critical part of owning the VSM. No one knows this more than he.

George. We need to know HOW bright it is. You must be comparing with something else (your previous amp, perhaps?). In my experience, ZH270 has much better and controlled bass than many other tube amps. In fact, I deferred sub-woofer purchase for a year. Your expression sounds like the "brightness" you suffer is not something cable swap or tube rolling can resolve. Did you buy it new? I suggest you check the ZH270 whether it is in perfect condition. Maybe you want to talk to David, who is known to be very sensitive and keen resolving these issues from his amps. Or, maybe it is just not your cup of tea.

You might try some Marigo bands and dots on your speaker cones and basket arms, especially on the woofers and midrange drivers. If you have any windows apply the Marigo dot treatment to them as well, if you don't mind their visual effect.

I have a very bright listening room, and a very sensitive system, and the Marigo resonance control products have helped me in very significant ways. Not only will they tame problems areas, they will also improve performance of your whole system.

If you choose to try these, do the woofer bands and windows first.

I share Duke's hunch on the issue of tonal balance. It is amazing how improving the performance of one element in the spectrum will improve other areas passively.