Hello Doug, it is indeed true and I am not the only one to say so by any means. Talk to Stig at Lyra and he will tell you the same thing and has posted to that effect on this forum.
You are correct that a low impedance is what is needed to detune the RF circuit. Also, SUTs don't pass RFI very well at all, so they can help too. But I find that SUTs also impair detail, so I prefer to do without them if I can.
You are also correct that only a few phono sections don't need the loading (obviously ours are examples in that regard), the thing is, its easy and cheap to fix this problem but as you surmised most phono preamp manufacturers (and quite well-known at that) don't even understand what is causing the problem so they are not in a position to fix it. So the myth survives quite easily.
One note- high output MM cartridges are different in that they are very much affected by loading at audio frequencies! But oddly enough, you hardly ever hear about anyone doing it, which is really too bad since many MM can easily keep up with much more expensive MC cartridges once the loading issue is addressed. |
Ralph,
Even if that's true (I lack the electrical expertise to discuss the point), my personal LOMC listening indicates that loading at 47K is optimal only with a minority of phono stages... typically, higher end units at higher end prices.
In most cases, including some all tube + SUT setups, showing the cartridge a lower load consistently resulted in better balance between the frequency extremes.
Perhaps your statement is true of better designs (like yours, I trust)? One might suppose that some of the "many people [who] simply don't know that RFI is at the root of the loading issue" may be phono preamp designers!
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Count me among them. Very interesting, Atmasphere. |
Further, with LOMCs you need to get into impedance matching. Unlike MMs and HOMCs, which are all designed to play into 47kOhms, every LOMC cartridge performs best with a different impedance at the phono inputs. The optimal impedance for any given LOMC is further impacted by all the downstream components in the system. This requires adjustability and/or custom matching of phono stage to LOMC. This statement is incorrect! (and is a common myth): nearly all LOMC cartridges load perfectly into 47K which is the standard input impedance of nearly all phono preamps. The 'loading' issue only exists if the **phono section** has troubles with Radio Frequency Interference! The reason for this is that the inductance of a LOMC cartridge is quite low- so it will not ring (distort) at audio frequencies. However, its inductance combined with the capacitance of the tone arm interconnect cable forms a tuned radio frequency circuit- that is energized by the cartridge itself. If you find that the loading value of the cartridge is critical, it means that the phono preamp is having trouble with the RFI thus generated. The loading value, if set correctly, detunes the RF circuit. RFI does strange things when it gets into audio circuits. Its best if the audio circuitry is immune to RFI. To this end, FWIW, transistor phono sections are more susceptible to RFI because the diode junctions within the semiconductors can easily rectify RFI. Special consideration has to be done on the part of the designer to avoid this problem, but you would be amazed at how many people simply don't know that RFI is at the root of the loading issue! |
Dougdeacon,
Thanks for you insight. Having just ordered a new table in the VPI prime and also have a good MM cartridge I agree the next step is a good phono stage. And your recommendation would be? |
The Quintet Black is a low output MC (rated at 0.3mv) with an MSRP of $1K.
So, given a cartridge + phono stage budget of $3K, would it make sense to spend $1K on a LOMC and $2K on a phono stage? Or would some other distribution of funds provide more sonic bang-for-buck?
In theory, the lower mass armature of a LOMC enables superior responsiveness to groove modulations (compared to HOMCs or MMs). This enables faster rise times, increased amplitudes and reduced overhang, IOW, a sound that's cleaner, clearer and more dynamic (micro- and macro-).
That's the theory. If you have a sufficient budget and choose your equipment well, it can certainly be a reality.
However, there's a catch and its a big one. Equalizing and amplifying a signal as low as 0.3mv and doing it well is neither easy nor inexpensive. It's the most challenging amplification task in any audio system.
Further, with LOMCs you need to get into impedance matching. Unlike MMs and HOMCs, which are all designed to play into 47kOhms, every LOMC cartridge performs best with a different impedance at the phono inputs. The optimal impedance for any given LOMC is further impacted by all the downstream components in the system. This requires adjustability and/or custom matching of phono stage to LOMC.
A phono stage that can do the above tasks well is costly. The one mentioned by Bpoletti is above your entire budget. Mine's more than double that. Etc.
Unless you're extraordinarily lucky, you're unlikely to find a high level performer for the demands of LOMC playback for $2K or less. Therefore, if you bought a Quintet Black (or any other $1K LOMC), you'd be unlikely to hear its theoretical advantages.
OTOH, you've already got a very good MM cartridge. You could put your entire $3K budget toward a phono stage. That would allow the 2M Black (or any similar cartridge) to sing at pretty near its best.
Finally, cartridges are consumable items, particularly the inexpensive ones. Phono stages are (or should be) a long term investment.
Sorry if I'm beating a dead horse. I see many newer vinylphiles caught by upgrade-itis and pouring money into the components in the wrong order. Until your table, tonearm AND phono stage are up to snuff, spending big on an LOMC is a risky decision that often doesn't pay the hoped-for sonic dividends. Buying a better phono stage (or table, or tonearm) always pays off.
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Sorry. I meant the Quintet Black. |
If you can get a Cadenza black for $250 more than a 2M Black, RUN and buy it asap! |
However, the list price for the Ortofon Cadenza black is almost $2000 more than the 2m black! [not $250!] |
I just recently purchased a Ortofon 2m black which is currently in my Miracord 50h Mk II. I plan on putting this in my new VPI. They also recommended the Ortofon Cadenza Black. Retails about $250 more than the 2M Black. I agree phono stage is will give me more bang for the buck now. |
"It is as sonically as good as it gets." Sorry, still getting used to a neW KeYboaRt. |
IMO, if you can spend a few dollars more, the Herron VTPH-2 will probably be the last phono stage you'll need. It is sonically as good as it VTPH-2 does not sound like tubes or solid state. It doesn't "sound" at all. It is just transparent to the signal. |
For the stated budget, I'd recommend an MM cartridge (or 2 or 3). Put as much of your $3K into the phono stage as you possibly can, you'll never regret it.
I've heard (and own) $200 MMs that compete easily with any sub-$1K MC, and most sub-$2K MCs. The extra $500-1500 you'd have to spend for a decent MC won't get you any better sound, because that money would come right out of your phono stage budget. At this price point, an extra $500-1500 invested in a better phono stage will provide much more sonic performance than the same money invested in a cartridge.
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From whom did you order the VPI Prime? What was their recommendation? |
