Here is a quote. I was not able to paste in the oscilloscope shots. He claims that this is quite a departure, and improvement on, the originals. Bob should get some samples and find out for sure. If they are markedly better, I can’t imagine why they wouldn’t be willing to sell or license them.
Our first attempt at a custom transformer looked like what you see to the left (above). This is as good if not better than every off-the-shelf transformer we tried. Please note the vertical scales are different. The original is set to 2V per division while this one is at 5V per division. 20 kHz at the left. 40 Hz below.
[IMG]
Though the top end was disappointing, the bottom end was stunning in comparison. The greatly improved power supply is a large part of it but still the transformer contributed a lot as well.
[IMG]
In our second try after exhaustive work by our transformer vendor over many months including testing of the original A470 we got what you see here at 20kHz. While the rise time is not quite as fast, that was the price to pay to get the excellent bottom end. The issue is that there is no overshoot and no ringing or distortion of the wave shape that cause issues. Our listening tests confirmed that the rise time was not an issue. The lack of ringing is what makes the high end magical. Here is what we got with the new transformer.
Besides preserving the high frequency and square wave response of the original transformer, we were able to extend the low frequency response to do justice to the dynamics and range of today’s music, recorded with the modern recording technology that is now prevalent. As far as we can tell, we feel these may well be the finest output transformers made for any tube amplifier, anywhere near this price point.
[IMG]
Our first attempt at a custom transformer looked like what you see to the left (above). This is as good if not better than every off-the-shelf transformer we tried. Please note the vertical scales are different. The original is set to 2V per division while this one is at 5V per division. 20 kHz at the left. 40 Hz below.
[IMG]
Though the top end was disappointing, the bottom end was stunning in comparison. The greatly improved power supply is a large part of it but still the transformer contributed a lot as well.
[IMG]
In our second try after exhaustive work by our transformer vendor over many months including testing of the original A470 we got what you see here at 20kHz. While the rise time is not quite as fast, that was the price to pay to get the excellent bottom end. The issue is that there is no overshoot and no ringing or distortion of the wave shape that cause issues. Our listening tests confirmed that the rise time was not an issue. The lack of ringing is what makes the high end magical. Here is what we got with the new transformer.
Besides preserving the high frequency and square wave response of the original transformer, we were able to extend the low frequency response to do justice to the dynamics and range of today’s music, recorded with the modern recording technology that is now prevalent. As far as we can tell, we feel these may well be the finest output transformers made for any tube amplifier, anywhere near this price point.
[IMG]
