Hi, Jolin and Ken. I hope all is well on your side of the world. How were your travels?
I want to tell you how much I am enjoying your ALIS-5SE Ultimate transformers in my 300B amplifier! I only have a few hours on them so far, but from the moment I installed them, I was very impressed with the sound.
I have been using Magnequest FS-030's in my 300B amp for maybe 20 years. I have tried other transformers from time to time, but the FS-030's have been a constant in that amplifier. I like their "voicing". Their response is weighted towards the low end of the spectrum. Bass is very solid and goes very low, but the highs are not as delicate and extended as they could be. I know that Mike from Magnequest designs his transformers very conservatively. They have lots of primary inductance, something like 30-35H, and low winding resistance. But this does make the physical size of the transformer quite large, which in turn causes it to exhibit higher parasitic capacitances and hence lower high frequency bandwidth. I'm sure you know how all that works!
When I installed the ALIS-5SE Ultimates, I heard a number of changes. First of all, and quite surprising to me, was the improvement in bass definition and detail. Although your transformers don't quite have the ultimate weight of the FS-030's, I can follow bass lines much more easily, and the pure extension is very good, despite your only having maybe 2/3 the primary inductance.
I am finding the high frequencies to be most appealing. I am hearing improved definition and transparency. Sonic images have more space and separation around them than I am used to hearing. There is an ease and naturalness that I really enjoy. I am also pleased to hear a reduction in upper midrange "glare", a touch of hardness that I would not have associated with the output transformers. All in all, a very transparent and natural sound that I am looking forward to living with.
This is not to say that the FS-030's sound bad or substandard in any way. Every designer makes certain conscious choices on how to "voice" his/her product. Mike chooses lots of inductance and low DCR, whereas you guys have chosen to achieve a wider high frequency extension with modest inductance. I can see someone with, say, a single-driver full-range loudspeaker preferring the FS-030's, as they would balance each other well. In my case, my loudspeakers use high-efficiency pro drivers. I have good bass extension from 12" drivers in vented boxes. I now find the bass nicely balanced and "tuneful". My high-frequency compression drivers/horns are very sensitive and have very low distortion, so I am able to hear the higher-frequency attributes of your transformers quite clearly.
This is not a formal review by any means, just an email from a satisfied customer! I look forward to living with these wonderful transformers, as well as integrating more of your products into my system in the near future.
All the best!
P.S. - For those that likes heavy bass, we have another model: ALIS-5SE MK2 that is meant for high Rp (plate impedance) tubes. The bass will be much better if used with low Rp Triodes! Using ALIS-5SE MK2 will have very good bass extension and quantity at the expense of some very high frequency loss. Still, ALIS-5SE MK2 specifications is very, very decent!
* Pentode: 20-65kHz(-1dB)
* Triode connected Pentode: 10-40kHz(-1dB)
(Note: pure Triode will have much better / wider bandwidth!)
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