Tona T 20/40 SUT - Moving Coil Step Up Transformer - made in Denmark
Latest update 17. December 2021
Usually when we here in Denmark talk MC transformers (SUTs or Step Up Transformers) most people will probably think of Ortofon or maybe Swedish Lundahl. But here it is somewhat surprising about a brand new Danish developed MC step-up from Tona Audio. The development has taken place in collaboration with Jakob Erland from Gyraf Audio. A quick look at his page shows studio equipment like mixers, microphone amplifiers, equalizers and more. Everything is with tubes and transformers both internally and at inputs and outputs. All with his own transformers. Now it is not every day the professional sound world and hifi collides, but here we have an example. It is also seen in the design. Should you have forgotten what an MC transformer is, it is for use between an MC cartridge and a normal RIAA input. For those who want to know more, there is an explanation on this page: - LINK. For a calculations with your own MC cartridge, you can find an Excel spreadsheet, which can be downloaded here: MC TRAFO – SPREADSHEET
Tona T 20/40 appears as a large "block" with the terminals on one side. On the underside there are 4 rubber feet. The solid wooden frame is included, but it is optional if you want to use it. There are two inputs - here balanced with XLR connectors. Converter cables are included, so you can also use normal. RCA cables in. One input has a turnover ratio of 1:20 and the other 1:40. The outputs are via RCA. One could have chosen a switch between the two inputs, but has instead Tona went for the more puristic approach with two inputs. Note that the two inputs cannot be connected at the same time. The box must definitely not be opened. In that case, the warranty will lapse and the orientation and alignment of the transformers will change, affecting the excellent data.The two inputs will give different loads as well as gain. 1:20 will give 26 dB gaih and a load of 118 ohm, which will be fine wiht most good MC catridges. The 1:40 indput has 32 dB gain and will load the cartridge with 30 ohms. (Both loads are with a 47k RIAA input). This latter input will be fine wiht very low impedance cartdiges with low output. Ie. Audio Note, Ortofon, My Sonic Labs and others. With my Ikeda 9Gss it was a perfect fit (0,28 mV out an internal impedance 2,8 ohms).
|Tona T20/40 wuth cables inserted. On the right my Lundahl LL1933Ag built into a copper box..||Converter cables from XLR to RCA are enclosed with the Tona. .|
Transformer technology and materials
Sorry, but now it's getting a little technical. The technology around transformers is a science in itself. I have touched on it in my test of Lundahl LL 1933Ag and here on the page MC-Trafoen - this is how it works(see link above). In my review of the Lundahl transformers, I describe it as follows: “Lundahl LL1933 is with mu-metal core (nickel) and the corresponding LL 1931 with amorphous cobalt core (amorpheus cobalt core). Whether one is better than the other, I should not be able to say, but there are differences ”. Swedish Lundahl himself describes LL 1933 as follows: "For those who prefer a low core distortion, and linear magnetic curve from a nickel laminate core" It should sound a little warmer and more comfortable, where the cobalt core in LL1931 is actually more neutral and a bit more smooth and revealing.
Toput it another way. It's a matter of taste. I then chosed the version with nickel laminate. Went for the sound at the expense of details. But here in the Tona MC transformer we have a completely third core material. A material that emerged in the mid-90s, but which has only recently been used for this purpose. A nanocrystalline core in the form of a ring core with hand-wound conductors. On the primary side, they use a thicker litz thread.
But what is the advantage of nanocrystalline cores? They have a much higher saturation and can transfer more energy despite smaller sizes. Precisely the size of a SUT can be critical when we talk about the number of windings and possibly loss. These cores have a very high permeability, high saturation, low coercivity and low core loss. One can reduce the transformer core compared to a traditional Ferrite core.
|Internally you see the laminatede soft iron build. Several layers ar bolted together. Picture supplied froam TONA- DO NOT TAKE IT APART!||Here a view from the bottom and up against the terminal with XLR and RCA connectors. The two round chambers are for the nanacrystalline SUTs.|
Tona T 20/40 structure
Tona says that the transformer is a good match for tube amplifiers, as the very high gain at 1:40 (31 dB) can be an advantage with low volume and use of (tube) RIAA preamps with a good dynamic range. At the same time, 1:20 with a more all-round 26 dB gain is usable for most pickups. A typical tube RIAA has a gain of about 40 dB, so with the transformer on, it gives resp. 66 and 71 dB. Even with my old Ortofon MC 5000, which only gives out 0.14 mV, it worked fine with the 32 dB gain. If you count on it, it provides 5.6 mV for the subsequent RIAA, which should be enough for most purposes. However, I primarily used the Tona MC 20/40 with my Ikeda 9Gss pickup via the 26 dB input. It provides an output signal of 5.5 mV to the RIAA.
The price may seem high, but compared to typical high end SUTs it's not wild. The best i have tried so fari is Ikeda IST-201, which cost approx. DKR 30.000,- (Euro 4000,-) There are few othe SUTs on the market with nanocryslalline cores. I could find the Consolidated Audio MC Step Up Transformer, which costs around 4.000 Euro. The Thrax Troja for 3.600 Euro and the small French Sculpture A - Mini Nano stepup for just over 1.000 Euro (specially desinged for the Denon DL103)..
• Two inputs - 1:20 og 1:40
• Can be deliverede with XLR or RCA
• Laminated lasercut soft iron chassis.
• Nanocrystallin torid core SUTs
• Primary resistance 0.1 Ω (1:40)
• Secondary resistance 25 Ω
• Induction matched transformers.
• Frequency range (5Hz-100kHz -3dB at 4Ω/20KΩ) – se measurement
• Phasedeviation (0.9 degrees at 20kHz)
• Stereo matched to 0.3 dB 20Hz-20kHz
• Rhodium phono RCA, gold XLR
Dimensions: 125 x 150 x 46 mm - Total hight 63 mm
Weight 4.1 kg
T 20/40 was used with several different cartridges. Primarily my Ikeda 9Gss and Hana Umami Red. However, there was also a FR MC201 as well as an Ortofon MC 5000 and a few other slightly older cartridges in over. An Allnic H-5500 RIAA was used, as well as the MM input on my Accuphase C-27 RIAA.
Heavy and solid
From the first notes I noticed that the rendering is open and weighty. There is a clear layer in depth and a resolution that captures the details in their proper place. It all seems much calmer and with profit. My otherwise excellent Lundahl LL 1933Ag had to see himself beaten at the finish line (The level differences were compensated for). It sounds a bit pressured in relation to Tona. Especially with voices and choirs, where many things happen at once, Tona maintains a rock-solid calm and an ability to separate it all from each other. It also has an amazing firm bottom octave and more control. Dynamically, it is also at the very top. All small strokes and echoes are exactly in the soundstage. Compared to the built-in transformers in the Allnic H-5500, there is more openness and dynamism. It all "breathes" differently freely. On the other hand, the price is also almost on par with the whole excellent RIAA from Allnic.
|Tona T 20-40||1:20||26 dB||118 ohm|
|Tona T 20-40||1:40||32 dB||30 ohm|
|Lundhal LL 1933 Ag||1:16||24 dB||184 ohm|
Billie Eilish with her new "Happier tthan Ever" offers an excellent voice and a somewhat melancholy mood. The sound is at times alluring and almost hypnotic and then changes to the violent and almost unpleasant. All aspects are clear and even in the violent sequences the overview is preserved. The voice is at the forefront with a wealth of details. Her singing and recitation is surrounded by air and with good space in the soundstage, In short excellent .
There was a brief change back to the MC entrance on the Accupahse C27. Nice and smooth, but lacks a little dynamism and some of the exciting and engaging in the music. Here we are then at the question of the SUT versus an active MC input. In this case, the vast majority, if not all active solutions, will be show their limitations compared to the SUT.
So how big are the differences between the three transformers I used? Tona T 20/40, Lundahl LL 1933Ag and the built-in transformers in Allnic H-5500. There are definitely bigger differences than e.g. between cables. I would rather say these are the same differences one can find between otherwise good cartridges. Not like between a good MM and a similar MC. The differences lie in the depth and precision of the soundstage, as well as in the microdynamics and the very small details. Also keep in mind that we are talking voltages of less than 1 / 10,000 part of a Volt. Differences that are magnified again after the reinforcement in your RIAA. Differences right at the source can definitely be heard.
I think it is brave and absolutely beautiful that Tona throws themselves into making a high end SUT. To be able to fully appreciate the absolute qualities it offers, it requires a good cartridge, as well as a good RIAA. I do not know how many potential customers there are in little Denmark. But those who have the opportunity should definitely try it, because this is world class. Tona T 20/40 is going out into the big world showing what we can do here in Denmark. It's a SUT that has shown extra details and more musical enjoyment from my favorite cartridges. It manages to create a great overview and a space that I have not experienced before. There's simply something more going on compared to the other top transformers I've tried. I have not tried everything, but the T 20/40 is definitely both versatile and well-sounding and should be put together with the best you can. I've kept it. In the future it will be a sublime partner for my Ikeda cartridge.
As these final lines are being written, Tona announces that they are developing a RIAA. It will of course be with LCR correction and nanocrystalline cores. So far, however, we have to wait il sometime during 2022 to see the result. When something happens, I will return.
BACK TO THE FRONTPAGE (In Danish)