Capacitance doesn’t matter.
Use whatever settings that sound good to you, but try at least 30 ohm or more.
Load Settings Help: Luxman E-250 and Koetsu Black Line
Hi Folks, I could do with some help as I don't understand load impedance or capacitance settings.
I have a Luxman E-250 for my phono stage which is connected to a Michell Gyro SE with a Tecnoarm 2 and a Koetsu Black gold line cartridge mounted on the arm. This all feeds a C900u and a M10x.
The settings on the E-250 are default but I feel there is more to be had with the sound based on some other similar setups i've heard. Could I get some recommendations on load settings?
Thanks @theflattire | ||||||
I think that you are misunderstanding how your phono preamp works. It is a solid state preamp with internal moving coil transformers that are in circuit when the MC setting is selected. All of the other controls are for setting the impedance, and capacitance, for MM cartridges, and do not work in the MC mode. You only have two choices of gain, and impedance, for MC cartridges 2.5 ohms (MC low) and 40 ohms (MC high). These refer to the internal impedance of the MC cartridge that you are using. Your Black is, approximately, 5 ohms internal impedance, so the 2.5 ohm setting is, probably, the preferred match, though no harm will be done using the 40 ohm setting, so it is worth a try. When doing these comparisons, understand that the gain will be different for the two settings, so it important to level match them when making comparisons. Generally MC transformers are expensive, so if you still feel that neither of those settings give you the sound quality that you are seeking, an alternative will be to set the e250 on MM mode, at 47k ohms and purchase a higher quality, outboard, transformer to step up the output of the cartridge. The Koetsu transformer is quite good and an obvious match to your cartridge, though only available on the secondary market at this time. | ||||||
@viridian Thank you. I completely missed that on this preamp. I'll have a play with the options at the front to test what sounds best | ||||||
Information on the maker’s site is pitiful "Black, Goldline, least expensive For many, their Koetsu journey starts with the Black Goldline. While it is the most affordable Koetsu, it doesn’t sacrifice what makes a Koetsu special. The Black Goldline uses many of the same parts as the higher end models and the result is effortless musicality and magic. "From the clarinets in the opening to the deeply textured final chord of the first movement, the Koetsu’s performance was impossible to ignore: This wasn’t just pretty sound in place of the music but sound as a part of the music." Art Dudley, Stereophile “The thing that really grabs me when listening to this moving coil cartridge is its overarching realism, musicality, clarity, and wide open extended sound.” Michael Corsentino, Positive Feedback
Specifications Anodized Aluminum Body Copper Coil Wiring Samarium Cobalt Magnet Boron Cantilever 0.4 mV Output 10.2 g Net Weight Recommended Tracking Force 1.8-2.0g Recommended Load 75-500 ohms $2,995" they don't even tell you it’s a moving coil, (the reviewer mention’s that it is) or it’s coil’s impedance (member viridian tells us above it is approximately 5 ohms coil impedance), or publish any performance specs for stereo separation or channel balance. they give a wide range of recommended load 75-500 ohms, and tell you it has a boron cantilever, but tell me, what stylus shape is it? guidance formula for loading a moving coil is start with 10x it’s coil impedance, which is approximately 50 ohms, yet they say 75 to 500 ohms. ........................................ top of the line, Blue Lace, $16k, this is all they tell you "Specifications Blue Onyx Stone Body Silverplated Copper Coil Wiring Platinum Magnet Boron Cantilever 0.3 mV Output 12.5 g Net Weight Recommended Tracking Force 1.8-2.0g Recommended Load 75-500 ohms $15,995" ...........................................
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still hopping about, found a review of a Koetsu Rosewood from 2007 with some info, but tell me what is the Stylus Shape? "Stylus: specially designed and ground for Koetsu" "Description: Low-output, moving-coil phono cartridge. Stylus: specially designed and ground for Koetsu. Output: 200µV (1kHz, 5cm/s). Internal impedance: 5 ohms. Frequency range: 20Hz–100kHz. Channel separation: >30dB/1kHz. Channel balance: within 0.5dB/1kHz. Recommended VTF: 1.8–2.0gm. Recommended loading: 5–100k ohms. Compliance: medium-low. Recommended tonearm: medium-high mass." a typo? Recommended loading: 5–100k ohms | ||||||
your Luxman Phono needs to be carefully understood, the MC High is not what I imagined, it will work with fairly low signal strengths, so you can try the MC Low and MC High options as suggested above
and it will accept very strong signals without overloading (as noted, caution with the volume when changing from low to high).
other settings should be understood (or restored to defaults perhaps), Your going thru your C-900U control unit via RCA unbalanced I suspect as the E-250 Phono has only RCA out, so the c 900U RCA in is 43K input sensitivity
so I would set the Luxman E 250 dip switches 1 and 2 for 47K impedance I don’t know, but would like to learn about dip switches 3 and 4 for capacity pF, anyone? | ||||||
As I understand atma-sphere (Ralph Karsten's) explanation, the lower your setting is, the stiffer the cantilever (& suspension) of your cartridge will get. The higher settings allow the cartridge to track more freely. I have found that many LOMC cartridges sound best at 47K ohms, even though that is the typical MM cartridge setting. I'd suggest that you start off with the 47K ohm setting & move down from there. At 47K you may have a brightness or glare If your phono preamp doesn't have a stable circuit. Move to 1K if that is the case and work down. Ralph explains it much better. But I've used 47K for many years with little or no issue | ||||||
I question this logic. The only way to load a cartridge at 47k on the e250 is to operate it without the transformers in circuit, so in MM mode. In MM mode, the gain is fixed at 38db, the output of the cartridge is .4mV. I doubt it is enough gain. The KAB gain calculator, while not perfect, yields a required gain of 58db for a .4mV cartridge, a full 20db above that available. https://www.kabusa.com/pregain.htm Also, it is worth noting that though the Koetsu literature suggests 75 ohms and above, that refers to an active stage, or the reflected impedance of a transformer. The transformers on the lux are marked 2.5 ohms and 40 ohms and that is not referring to what the impedance of the transformers are, it is referring to the impedance of the cartridge that it will be matched with, which is .4 ohms for the Black Goldline. Confusing, I know. Where is Dave Slagle when we need him? | ||||||
My third to last sentence should read 5 ohms, not .4 ohms, sorry about that. Koetsu is now out of business, so it may be moot, bit they, and Lyra are the only two companies that I am aware of that had proprietary dimensioned stylii ground for them. The Lyra dimensions are specced, but Koetsu considered it a trade secret, and never specced the dimensions. It is common knowledge that it is a line contact, probably similar to the Ogura Vital. Artisanal audio is often short on specs. | ||||||
I did not know the specs on his phono pre and was/am going on the assumption that he could use 47K with a 60db gain as I can. My mistake in this particular instance. .But the idea is still appropriate for those who’s phono pre can load 47K with the MC gain. I have done this with several cartridges. But considering that the OP may be somewhat new to MC cartridges its good that you pointed this out. | ||||||
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