Can anybody define LOW OUTPUT...?


Hi. I'm currently pursuing the insanity of trying to decide on and purchase a really, really good used low output MC (only because it seems - in theory at least - that there's more detail to be had there). At any rate, my phono stage was designed for a Linn Troika cartridge (low output - 100µV - that was a MU - in case you don't have a mac also!) - yet I've been looking at some van den Hul low-output MCs that are something like 5-6 TIMES higher output than this - I'd imagine that would put the vdH at LEAST in the MEDIUM output camp. Am I missing something here? Can anyone APPROXIMATELY delimit (spell out for me) the boundaries of what is commonly considered low, medium and high output?

Thanks much.
Jonathan
letranger
Generally speaking a HIGH output (MC or other) cartridge is one that could be used with a standard phono stage/preamp, that would normally be for a moving magnet cartridge, etc.

Lower output designs are used in the hope of lowering the noise floor, in order to have the most refined, accurate and transparent sound . This explains why most phono preamps for low output cartridges are on the expensive side. A cheap MC (high gain) phono preamp would introduce the noise that the cartridge design was trying to eliminate.

Depending on your phono preamp, you may want to choose a cartridge that goes well with that particular preamp. Many better high gain phono preamps are adjustable, but you should check to see if it fits your cartridge choice in any case.
I would not get hung up on the terms High/Mid/Low output. It is like trying to define what is really meant by "low fat" on product labels.

I doubt any audio designer ponders very much about how a design will be classified in the market place (low/med/high). It is low or high to them.

The matching with/to the desired phono preamp will matter more in the long run. This is not hard to do. There are great sounding cartridges at all output levels.
Is the Troica's output really that low?

As a rough guage, IMO only and YMMV,
Low < 0.4mv
Med 0.4 - 1.x mv
Hi >2mv

What's more important is the matching of the cart's output to the phono's gain.

For the low output MCs, gain required is approx >60db, med output you could get by with >50db, and the high output require about >40db.

I maybe wrong, so if someone else can shed more light, pls go ahead.
This actually has a very real application (believe it or not). I'm going to pack it in with my preamp phono stage if 0.1mV is FAR lower than something I end up buying. So - if the 'low end' - or, in other words, what most designers AIM for is above 0.25mV then I probably need to find my game somewhere else.

thanks for the input, though!
Jonathan
If that phono stage is really designed for the Linn Troika then it should be presenting a load of 560 Ohms and has maybe 70 dB of gain. You are right that this is more gain than many moving coils need, but it's hard to guess without knowing the component specifications a little better whether this will overload the complete chain (phono-line-amp-speakers-room) when driven by a cartridge with 5 times the output.

Even if not overloading the system, you may not be in a very sweet spot on the volume control - too much volume at very low settings.

There are a few moving coil cartridges that also have a very low output like the Troika, although I can't think of them off hand. What about a Troika?

Can you try the cartridge you are considering before you commit?

Regards,
Thank you very much for your considered response... I think this is getting me closer to deciding whether to commit to a troika or try something else and change my phono stage out for something else (luckily my preamp (naim) uses different interchangeable boards for the phono stage. I just wanted to know how much of a problem this might be. Another pickup I was considering was a vdH - at around 0.5-0.6mV.

What IS interesting is that I'd be willing to bet that using an overly sensitive phono stage would CONSIDERABLY change what I'll call the 'electrical profile' of the signal being sent to the power amp (impedance, etc...). I wonder how audible the difference would be.

Jonathan
using an overly sensitive phono stage would CONSIDERABLY change what I'll call the 'electrical profile' of the signal
Well, amplifying a very small signal is always prone to external attack (noise, etc). Also, in a smaller signal you're more dependant on the amplification & the wires, whereas in a higher signal you;re more dependant upon the quality of the coils...
Mr V den Hul once said that, ultimately, one might be better off with a higher level signal fm the cartridge and depend less on the phono. IME, differences were slight either way...

One thing that's palpable is: it's usually cheaper to get more output fm the cartridge than the extra 15db (10? whatever) amplification fm an outstanding phono. Cheers
CMK has it right: low output is around .25 or .3 MV, phono section gain needs to be 60db or so.
I've always thought the low outputs were better.