Quote:
Originally Posted by Giganova  Well, guys, you might be in for a surprise:
A) Lundahl transfomer
B) Chinese stock transformer
I think that the Lundahl transfomer has a much tighter bass, but the Chinese stick transformer has more high-end. Also, the Chinese stock transformer has a +3dB higher output signal, which surprised me and is critical as the ribbon mic requires a very high gain anyway.
Overall, I think that the $60.- Lundahl transformer did not give a dramatic improvement in sound to justify the costs -- if any improvement at all. So, next time you hear fairy tales about how an output transformer mod will "open up" your ribbon mic sound you know how to interpret these statements. |
I've stayed out of this discussion mostly because I've just gone through a similar process and already knew the answer. I purchased two Alctron HRM10s last year (same as Nady RSM-3). This year, I bought two Lundahl transformers for them. Rather than just installing both, I put just one in, then compared the two mics. The mic with the stock transformer had a much brighter sound - not bright, by any means (these are ribbons after all) - but much more usable high end on the stock unit than the Lundahl unit. I was very surprised (and disappointed) to see this result, but it is entirely consistent with Giganova's results.
The Lundahl did seem to extend the low end somewhat, but that's not what I was hoping to achieve. And for me, it is especially disappointing in cost terms. Since I bought my HRM10s in last year's group buy, the Lundahl transformers cost almost as much as the mics themselves!
The only thing I might point out is that both of these mics (Giganova's and mine) use a fairly high impedance ribbon when compared with some of the other Alctron ribbon mics. It may be that the Lundahl transformer just isn't a good match for these particular mics. They may behave very differently in other models. Note that both the HRM10 and the HRM14 (which is Giganova's CR-14) have a 600 ohm impedance in their stock configuration. Most other Alctron mics have a 200 ohm impedance.
Incidentally, my tests were made using real acoustic instruments and with the two mics positioned closely together in the same orientation. And I also tested with the two mics in reversed positions just to make sure that the inch or so between them wasn't impacting the results.