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
With my ProAc 2.5's, I alternate between a CJ 11A and a Pass X-150. Both work very well. I'm sure there is a poor amplifier choice for the 2.5's, but I have trouble imagining what it could be. (I'd love to try the Berning, by the way.)
Ken

Not to get too far off topic but as a long time Berning owner I would be interested in your comparison of the single ended zero feedback Siegfried to the PP variable feedback of the zh270. I'm sure Twl and others would be interested as well. Thanks.

Allan your statement changing tubes is for tastes, not to bring up performance is an interesting one. While I would agree that changing the inputs was more of a taste thing, my opinion is that it also improved performance.

So far as the cryoed treated 6jn6 outputs are concerned, there was DEFINITELY an improvement in performance, more resolving, more dynamic and just better across every parameter that I can describe, nothing subtle here. It seems Oneproof feels the same way. I really don't think this is a taste issue at all. And who should know better than you.
Tubegroover, I wish I didn't sell the ZH-270 quite so fast so that I could do proper justice when answering your question. I had been running a Sony SCD-1 cd player directly into my ZH-270 and then my Siegfried. After selling the ZH-270, I bought a used Berning TF-12 preamp--I needed the additional inputs. I expected no sonic improvement and hoped only for minimal degredation. The big surprise was that the TF-12 actually IMPROVED the sound, giving voices a organic wholeness and solidity that makes it sound "right". The Siegfried volume control is turned all the way up now. I guess that the TF-12 volume control is somehow more transparent.

I don't know whether the TF-12 on the ZH-270 would make a similar improvement or not. David Berning himself commented to me that he didn't see what a preamp could add. I was always thrilled with the inclusion of an A/B switch and volume control on the ZH-270 so that I didn't need any preamp. However, it may make a useful difference there as well. What is your experience here?

My speaker is the JBL 4344Mk2, a 95 db/2.83v 6-ohm speaker. There is an impedance peak of about 20 ohms in the bass register. I was using rather spindly speaker cables which suited the ZH-270. Going straight from the ZH-270 to the Siegfried without a preamp I immediately noticed enhanced dynamics, but weak bass and confused imaging. Switching to Harmonic Technologies heavy duty speaker cables firmed up the bass and gave an overall more open sound for the Siegfried. (I liked the spindly cables for the ZH-270, though). The other change I needed to make was to replace the Red Rose 1 interconnect between the SCD-1 and the amp with something smoother: the Kimber KS-1011 did the trick. There may be others, this one is fine.

After all these changes, I am not sure whether we are comparing amps anymore! However, the overall effect was a much more articulate and dynamic sound for most music at moderate volumes. When I say "articulate" I mean, for example, that you can hear the words of songs that much more easily without any bizarre artifacts like siblance, etc. When I say "dynamic" I mean that the inflections of various instruments are that much clearer, even when they are playing all at the same time. Music is more lively and interesting. It sounds that much more like people are playing it rather than it just "happening". Does that make sense? I don't think that it is a tonal change.

Tonally, the two amps are similar, but the Siegfried has, I think, a more open high-end and somewhat more resonant bass on my speakers despite the lower output impedance. Is the high end difference related to feedback? Maybe. Listen closely to how the fine details of cymbals, etc. are rendered at different feedback settings. I found that the high treble fell off at the low feedback setting on the ZH-270, yet paradoxically there was very a subtle improvement in clarity. Overall, though, on my speakers, I found the high and medium settings best: the high setting gave me a tight, fast sound and medium a more organic sound. Low feedback was sometimes alluring, but didn't hold my interest in the same way.

The ZH-270 beats out the Siegfried when it comes to volume. It can get louder and louder without any noticible strain on my speakers. It just "puts out" the sound and remains confident, open and tight. The Siegfried, by contrast, starts to sound a little hard and compressed on peaks if you push it over its limits of a few watts average. That happens on large orchestral work including, ironically, Wagner's Siegfried!

People often comment about the "speed" of the ZH-270 and I noticed it, too, especially at the high feedback setting. I rather liked the effect, but don't believe it is particularly natural. After all, when was the last time you listened to live music and remarked that the sonics were really "fast"? I suppose I prefer fast sound to slow, but the best of all is one which doesn't even raise the question. I have forgotten all about this with the Siegfried: it just seems to get it right.

Can I have the best of two worlds of high dynamic contrast and power? My current project is to build a more sensitive (100db/w) speaker to see what happens. In the meanwhile, the answer is to play at moderate volumes and enjoy the sound even if it means giving up visceral impact.
Ken, I am doing just that. I have a pair of Lowther EX3's in modified Voigt Pipes(100db), and I have a special order cutom amp coming from David Berning. It will be a battery powered, choke-loaded, SET ZOTL, with type 45 output tubes, and 2 watts nominal. I will be using the Emission Labs VV45 Mesh-Plate tubes. It will be loosely patterned after the Siegfried, but with the obvious differences of battery power, and choke-loading, and of course the type 45 tubes. Some people I've talked to are calling it the "Holy Grail" of amp designs. Probably pretty close.
Ken I find many of your comments interesting. So far as sibilance is concerned I have often found this to be the result of interaction of components and wire and have experienced my share of it. I have never heard this emphasis through the zh270 or the previous Transcendent OTL amp I used. The system is wired with copper interconnects and Millersound speaker cable which is aluminum with covered with a copper flex wrap. I have been using the Millersound in my set-up since I had the Transcendent and it works extremely well to the point that I have stopped looking for "better" speaker wire after going through numerous ones.

The interconnects (Luminous Technology Synchestra Signature) were a notable improvement over the Harmonic Technology Truthlink. The Berning allowed me to hear that Truthlinks are intrinsically smooth sounding cables but somehow there is a sameness to all music, much of the subtle nuance of the performance is missing in action. As it happened a friend bought a pair of Luminous cables and his system transformed, I don't use the word lightly. There was that organic wholeness and a separation of instrument lines ala live music that you speak of that were revealed when one cable from the pre to the amp was installed. It was the most significant improvement I have heard his system make and this includes even swapping the Berning in. To put this in some perspective, he has tried numerous cables including MIT, Exos, Harmonic Tech Pro-Silways and Truthlinks, Tara labs, etc. each resulting in differences and some improvements in one area at the expense of another. The Luminous was a revelation and trying to analyze what happened took a back seat to listening to the music prior to which I had a difficult time doing with this system because I always was drawn to the artifacts of the reproduction, in a word, fatiguing.

I don't want to get into a cable review because my point is to emphasis not only do cables make a difference as you note above, they can make a DRAMATIC difference in bringing out not only the musicality of a system but the artistry of the performance. After hearing this in his system I did some research on the cable to see if there is a reason why it should make such a difference. Pretty straight forward, 6 nines continuous cast, (the truthlink are also continuous cast) with a special termination that may come into play. He brought the cable to my place the next weekend and while it didn’t transform my system like it did his, it was certainly a big improvement in the areas that I felt the truthlinks to be weak. Nuance or realness conveyed much better, which I attribute to greater resolution of harmonic detail, tighter and better control of bass, and probably the most notable, to me an incandescent, airy natural portrayal of the upper frequencies.

My litmus test of how my system is performing is massed vocal recordings, Ode to Joy Beethoven's Ninth John Elliott Gardner on Archiv is a good example. Nothing is more difficult to reproduce and very seldom do I get goose bumps listening to a choir on a stereo system. It is generally so far off the mark of the real thing. The speed I speak of with OTL’s and the zh270 is the ability of the system to reproduce instruments and vocals without overhang or adding a richness and to keep everything together yet to reveal the air, space, image focus and separation of the performers as we might hear it in a live performance. I would think if an amp is too fast, if this is possible, it would have the same effect as a tt platter going too fast, there would be a chance in the pitch of the instruments and voices. What could be perceived as artificial is if the dynamic shadings of the music aren’t keeping up with the above, this could certainly lend a perception of something being amiss. At this level of performance in an audio system, each element of the chain has to complement the others or whatever area has a shortcoming will draw attention to the whole.

Your insight was most welcome. I am currently going direct from the digital source to the amp. Prior to installing the Luminous cables, I was going from my CAT SL-1 pre to the amp and preferred it somewhat better with the truthlinks. There really wasn’t an earth shattering difference. With the Luminous cables there is a big difference and I much prefer direct. The presence on a great performance is palpable. Performances can swell you with emotion. It is a level I’ve never experienced before and it is consistent with music I love and the effect I get when attending a great live performance. I now realize that the pre-amp has to go and have just ordered a new one recently. I wasn’t particularly happy with the phono stage and the line stage is now just ok. I sure hope this new pre can keep up with what I am currently hearing. If I’m real lucky maybe it will be an improvement. What I’m really looking forward to is the phono stage. The bottom line with the zh270 is that I have finally found an amplifier that can showcase the potential of my system. Of course it doesn’t hurt that my speakers are a nominal 8 ohms with no dips that could alter the tonal balance. I generally prefer the normal setting with great recordings. I listen equally as much through the medium setting going back and forth often trying to decide. I only listen to the low feedback setting on overly dry recordings. As Peter notes, it is a bit too ethereal, not real but still pleasing. It’s nice having the flexibility. I sure would love to hear the Siegfried on Siegfried (Wagner’s)