Problems getting the best out of my Berning


Hello fellow Agoners,

I beckon for help from experienced users of the Berning ZH270! I just received mine new a week ago, and although it is an incredible amp, it is not meeting my expectations. HELP!

First the good news:

This is the fastest amp I have ever head, and it has virtually no noise floor. I am truly impressed with these aspects. It handles most everything with ease and clarity.

Now my system:

Proac 2.5 loudspeakers
Cary CD308 and Arcam FMJ CD23
Kimber PBJ Interconnnects
Audioquest Type 4 cables

(I've also used Dynaudio Audience 72's and all MIT cables, and Triangle Titus + Audioquest Slate cables and PBJ IC's).

OK - now to the problem:

On all three setups mentioned above, the amp seems strongly biased towards the midrange and upper midrange, resulting in a fatiguing presention. There is a significant decrease in bass (not detail, but the actual movement of air) from the other amps I have used for comparison (Classe CAP 101, Pass Aleph 3, Adcom GFA 5400). While the detail and fastness are truly amazing, the midrange emphasis is getting the worst of me!

I've spoken with David Berning and Frank S (FS Audio.com) and both encourage some tweaking to get rid of this perceived (psycho?) acoustic bias. Frank is going to send me some interconnects to try. David mentioned that others have changed the tubes. He doubts anything is wrong with the amp.

Is this all in my head, or have others had similar problems and needed to make adjustments to get it right? While all my other amps are currently SS, I have trouble believing that this is the "tube sound" (I've heard other tube amps). Other threads mention system tweaking to get rid of a "glare" with the ZH270, changing tubes, sensitivity to cabling. My perception of the sound is pretty strong - currently I like my Aleph 3 a whole lot more with the existing setup.

I'm willing to put some time and money into making this work - because in all other respects, this is an absolutely amazing amp. Perhaps it doesn't suit my ear - but I want the advantages of this amp without the disadvantages I just mentioned. Please - suggestions on what to do from all you experienced Berning fans... so many high commendations cannot be that far off (right?).
peter_s
Peter-
Great summary in your last post. My TG Audio speaker cables use banana jumpers.
I have asked another guy to chime in here, too. He's on the west coast and has a Berning, Proac 2.5s and a Cary 306/200 with vol. control.
I heard what you said about the 308 being OK in OTHER systems. I'm sure that's true. But now - in your current system - something is wack. Out of the box, my Berning was great. I can't imagine cables being the culprit. You know the deal, peter - system synergy is key and, at the risk of being redundant, your cdp may be the culprit.
Who knows, maybe things will mellow in the next few days. When did you install it?
The amp only has about 10 hours on it total. The other CDP I'm using with it is an Arcam FMJ CD23.
Peter, don't spend money chasing cable upgrades until you figure out what is going on. In my experience, no cable change will fix a fundamental system problem, which is what it sounds like you have.

But do give the amp more time to break in. Do you have another amp you can try to see how much of the problem is directly related to having the Berning in the system?
Peter I'm with Ian, your summary was great and I think the problem is narrowed down. Based on what you said I believe there is a tube problem somewhere, more than likely the inputs. You should be getting more bass than you are. This amp goes down to 2hz, almost dc into an 8 ohm load. The bass performance shouldn't even be an issue. With the pro-acs 8 ohm load you should note a big improvement in the bass with the zh270. Further I am really mystified by this glare you are hearing; poor bass, tube glare from the zh270, its gotta be a tube problem.

Try Brendan at tubeworld.com and just get the tubes recommended above, shouldn't be more than 175.00 or so to upgrade all 6. You'll want to do this down the road anyway, it is a great improvement and may just solve the problem. I really believe you have a tube mortality somewhere or a weak tube causing this anomaly. Try this FIRST and forget the wire for now. In the meantime see if you can locate a tube tester. I also don't believe the problem is with the Cary CD308. And keep up posted on the results.

When you get it right then you'll want to try those cryoed tubes for one of the best audio expenditures you'll ever make.
Tubegroover - would you go for the Cryo'd tubes first? Or do the NOS first? Thanks.