It's been almost a year since my favorable review of this Finemet MC step up transformer. Overall, it has given me great musical pleasure! However, when tasked to amplify MC phono cartridges with lower output than a typical Denon DL103, in particular the Ortofon SPU and Fidelity Research FR1 MkII, hum could be intrusive in softer passages of classical music, especially when not carefully sited away from motors and power supply transformers.
As I had suspected in my initial review, the FM-MCT1 wasn't as well shielded as the Hashimoto HM7, Tamura TKS83, Altec 4722 and other vintage MC SUTs in my collection.😔 Now, I had no recourse but to compromise my aesthetic preference for an open chassis in favor of an enclosure to provide additional shielding.
Looking back to my late 90s home brewer article for Sound Practices issue 17, I noticed that a good number of components in my hifi system then are still serving two and a half decades later. The Tamura TKS83 moving coil step up transformer is one of them.
After building a hifi system for my cousin during lockdown, the Hashimoto HM7s made me realize that while the Tamura TKS83s can equal the HM7s in terms of bandwidth, the TKS83s can sound mechanical. It also became apparent that there are areas in which the classic Altec 4722s and 15095As can be improved upon.
When I finally heard a pair of Peerless 4629s, I was very impressed by their uncanny ability to reproduce very lifelike 3-dimensional vocals. However, I was quite disappointed when I played anything greater than a string or jazz quartet because the sound started getting mushy and dynamically compressed.
Overall, my ears still prefer the smaller and more affordable brother, the Altec 4722!
Upon our return from the expedition, a sumptuous dinner prepared by Tish + a bottle of Ripasso awaited us. We capped the evening by hooking this wooden box to my hifi. Our jaws dropped each time we played an LP!
In the ensuing days, I did further evaluation and indeed, these Finemet MC transformers are doing something extra special. My only reservation was, in spite of the potted construction, the FM-MCT1s are more susceptible to hum induction compared to the Altecs and Tamuras. Even if John lined the wooden box heavily with copper shielding, I still had to keep them away from power transformers, AC motors, etc.
Kimura-san specified a 3-4 week window for delivery. So I downloaded the spec sheet, studied the schematic and ordered a cast aluminum project box from Amazon.
Within 18 days, the transformers were at my doorstep.👏
These are very well made and quite hefty! They're heavier than the TKS83s which, if memory serves me right, are about the same weight as the HM7s.
I chose a different layout for the 145mm x 121mm x 40 mm MC step up transformer chassis for neater routing of RCA cables.
Under the hood
The input and output RCA jacks are on the backside mounted on top of the chassis. Only the ground lug was mounted on the side.
I installed the 3-position gain/impedance load selector in front of the chassis.
No matter which cartridge I used - Denon DL103, -R, -C1, Fidelity Research FR1 MkII, Ortofon SPU #1s, -G, -GM, Supex SD900, etc. - male and female vocals + instruments are portrayed with 3-D presence and realism in a deep and wide sound space. The musicians are in my man cave!
Boosted by the Finemets, even the most analytical and dry-sounding MC cartridges in my stash, like the Goldbug Clement II and Sony XL44 came to life with more warmth. If that's a coloration, it's certainly most welcome!
These Finemet MC transformers seem like they were configured to resolve every note in the complex musical score and massive instrumentation of late romantic symphonies along with the wide range dynamics from pianississimo to quadruple fortes inscribed therein by the composer. They also excel in reproducing the ambience, airiness and spaciousness of the concert hall's acoustics embedded in well recorded LPs.
I finally found a pair of MC transformers which combine the organic midrange and harmonious richness of classic vintage iron + the wide bandwidth, detail retrieval, and dynamic range of modern magnetics!
Ever since I became an audio DIYer, I pride myself in not being impulsive about upgrading components in my hifi. This is a rare exception!😉
CODA
As luck would have it, last week we had a family get together because a cousin based in Tokyo was visiting and brought some goodies!
This was the last extensive testing and listening session I did in the attic before we moved back to the states. I misplaced some data and just recovered them recently. So as promised in a previous blog entry, here's the write-up on the two entry-level SE Finemet OPTs from Noguchi.
WARNING
These are bonsai-sized output transformers. If HUGE iron + HIGH inductance and thumping bass frequencies is your idea of high-fidelity you should STOP 🛑 here!😉
However, if the finesse and realism a WE/Altec 755A can provide within its 70-13 kHz bandwidth is your idea of a GREAT time, please proceed!😊
Noguchi FM-3WS-H
Noguchi FM-3WS-H + Tamura F7004
David vs. Goliath - indeed, the FM-3WS-H is tiny. I had to mount it on a perf board so that it wouldn't fall from the square mounting hole left by the Tamura F7004 ;)
Technical and listening tests were done with the output transformer mounted in the Radiotron SE2A3 stereo amp in place of a pair of Tango U808 OPTs.
Color Chart in Kanji
for wiring
transformer leads
Subjective evaluation of both OPTs
I have to admit that given the Lilliputian dimensions of these OPTs, I was predisposed to expect poor bass performance in spite of the claims from their respective spec sheets. The 100Hz square waves verified the manufacturers' claims and the quality of bass I hear more than compensates for the lack of ultimate extension which, in my experience, can only be had from OPTs the size of a Tango XE60/NY15s or Tamura F2000/F7000 series. In fact, when I invited my seasoned DIY Audio buddies for a listening session, none of them noticed significant bass deficiency.
Back in the 90s, there were two types of exotic transformer core material vying for the best - Permalloy and Amorphous. I learned then that the virtue of exotic core material shone through the mid-range, rather than at the frequency extremes. I never quite made the leap to Amorphous because I was already satisfied with the life-like mid-range abilities of Permalloy. I heard the Amorphous Tamura F5002 in a familiar circuit and system context, and thought that in spite of its edge in resolving detail, it sounded clinical compared to Permalloy. Finemet is supposed to have evolved from Amorphous. However, the mid-range performance from these two entry-level Noguchi Finemet OPTs have the warmth and lucidity of Permalloy without the antiseptic quality of Amorphous.
With such fine midrange performance I didn't expect any high frequency aberrations and the two 10kHz square wave oscillograms above confirm the smooth falling response beyond 20kHz (no ringing or phase shift), as shown in their respective spec sheets.
