Well, every time it is a different story. I am not affiliated with Mercury Magnetics in any way, I am just happy customer who was given a helping hand. I know the opinions floating thru the web about their prices. I agree - their transformers aren't cheap, but to me their iron is worth the money, period.
What is even more important - they most of all wanted to help and their goodwill was awesome. As I described that already, I had a problem when I couldn't get a replacement OT for my amp. I decided to put the one that most probably was the example for Bogner OT's - Dagnall C2668. The amp's response was quite nice, but the sound was a bit too "vintagey". So I decided to put more modern design to my amp and wrote to Patrick at MM describing my problem. After a long long conversation he offered me PX-100, saying that I could exchange it for another OT in 30 days if I'm not fully satisfied. And I wasn't, as the tone became too "Mesa-like", taking out all Bogner flavour.
Besides, PX-100's mismatch with amp's B+ caused another thing here. I measured the impedance of the amp-to-cab output and it occured that when the impedance switch was set to 4 Ohm, the meter showed 16 Ohm, when it was at 8 Ohm - meter showed about 40 Ohm, and 16 Ohm - about 70 Ohm. That showed how the PX-100 was totally mismatched with my XTC's B+ and I suppose that such mismatch caused such tone. I have also measured my Marshall 6100 and everything was perfect there: 4 Ohm setting - 4 Ohm on the meter, 8 Ohm - 8 Ohm, 16 Ohm - 16 Ohm.
So Patrick said that we won't try any other Marshall OT from their line-up, as it wouldn't match again, and offered me custom OT wounded to certain specs we discussed. It was his idea, not mine. It turned out that the tone would be better if the OT would match B+ of an amp. As I have that OT in my amp the impedance mismatch has gone. So it is actually their new design for XTC 101B.
Another thing - they have sent me that custom transformer in exchange of the previous one, with no additional costs. I was only supposed to send them back the PX-100. I was totally surprised in a good way of course, because I am the just regular customer and they took great care of my problem, finally solving it for good. Maybe for those of You who live in western countries it is totally normal, but I come from the land where such customers treatment is an exception

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As for the tone - all is subjective here, no doubts about that. But there was significant difference between Dagnall C2668 and MM PX-100, same as between PX-100 and my custom OT. The amp's response is now very quick, the tone have become more focused. From the other hand, the custom OT gave back all Bogner flavour the PX-100 took away. So the guys in MM really know what they are doing. I will try to compare my amp with regular 101B but as for now I am very happy, only waiting for my OT to be fully "broken-in"

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So, not only a tone was a key here, but also the way of dealing with customers. Both aspects caused that I don't regret any single $ I paid them

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Regards, Andy
