Problems getting the best out of my Berning

I loved my ZH270 and still miss it, but I couldn't afford to keep it after I bought a Siegfried...

In addition to the many things you've already mentioned, I found that the ZH270 was sensitive to the type of feet it sat on. My best results were leave out the cones and spikes and use the standard plastic feet on hard, heavy surface.

Cables do matter! The Siegfried is merciless in revealing colorations in the input cables...more so than the ZH270. I get nice neutral sound from Kimber KS-1011. I found that my two "silver" cables had undesirable "zip" in the sound on the Berning amps. Also, I found that monowiring gave a more pleasing sound than biwiring. I use the same biwire cable as before, but I connect the the high and low end cables together again at the speaker end. This gives me a much smoother high end. Your experience will surely vary, but it might be worth a try.

Are you using any power conditioners before the Berning? If so, try without them. I get noticibly better results with the PS Audio Ultimate Outlet.

After buying my Siegfried, I horsed around with substituting NOS tubes of various types. David Berning warned me that it can be a "real adventure" in finding tonal balance...and he was right! I am now back to the original tubes, including the ordinary Sovtek 6SN7s, and all is well. I was able to get best results by choosing different cables and repositioning my speakers.

Do you get the same tonal balance from both speakers? Try right and left alone with a mono signal from your preamp. If they are strikingly different, try swapping right and left speakers to rule out differences in tone to speaker placement. If the problem is in one channel, then you may indeed have a problem with your amp.

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.