Benz Micro Glider Loading
Hello,
I have an original Benz Glider. The measurements that came with the cartridge is .9mv and suggested loading is 1000-47k.
I ran this into a Krell KSL w/phono stage at 1k with good results.
I’ve also ran this into a Rogue Audio Model 99 Magnum with tubed phono and Hagerman Piccolo head amp at 1k with good results.
Right now, I’m using a MoFi Studio phono pre and am running it at 1k.
I’ve tried higher and lower load settings and to my ears, 1k seems to be the sweet spot.
I’ve been looking at phono pre’s on Audiogon and USAudiomart. I noticed some of them don’t have 1k loading as an option.
Should this deter me from considering these units?
I noticed after doing some research that others have been running their Gliders at much less than 1k. I found that running it much below 1k kind of sucked the life out of the sound in my experience.
I should mention that I had the Glider retipped with a micro-line stylus profile. The original was elliptical.
Admittedly, I may not understand loading and how it works as well as others. I can only go by what sounds good to me.
No- it can act as an antenna for RFI, but the input of the MP-3 is built to reject RFI.
@nicktheknife That preamp is designed by John Curl, who knows what he's doing 😁 |
@voolston You can imagine that if I'm aware of this issue facing all phono sections that we would make an effort to see to it that our phono section didn't have a loading problem... |
@nicktheknife You will have to listen. Designers are not in the habit of letting you know whether they know what they are doing or not. My point was that 1K isn't needed if the phono section is properly designed; the industry stock standard of 47K should be fine. |
@nicktheknife When dealing with a cartridge of this type the loading is for the benefit of the preamp, not the cartridge! What is going on is the inductance of the cartridge is in parallel with the capacitance of the tonearm cable. Whenever inductance is in parallel with capacitance you get a resonance. In this case it can be from about 50KHz up to about 1 MHz depending on the capacitance of the cable and the inductance of the cartridge. If it goes into 'excitation' (a Radio Frequency term meaning that the resonance is oscillating and is making a signal) then that signal is injected into the preamp. Audio information can send the resonance into excitation even though its not the same frequency! The result is RFI is being injected directly into the preamp and could be overloading it. This would cause distortion (brightness). By 'loading' the cartridge, you detune that resonance and excitation can't occur- the problem goes away. If the phono section designer understood how this happens, the phono section won't be sensitive to RFI at these frequencies and so won't care about the loading either- it won't affect the sound. However, when the loading is used, you are asking the cartridge to do more work! Normally it has to drive 47,000 Ohms but now its only 1000. nearly 5x over a magnitude more work- and that work comes with a price- the cantilever, which does the work, becomes harder to move. This causes the cartridge to have a lower compliance than the spec sheet says and may lead to tracking difficulties if you were paying attention to that when the cartridge was bought and set up in your arm! In addition the stiffer cantilever may make higher frequencies harder to trace. The bottom line is when you see a preamp that has loading options on a switch it means the designer did not think about the implications of an inductor in parallel with a capacitance (which is your first week of electronics 101 class). Take that for what its worth... So not having such a provision is not always a bad thing. It might mean the designer knows what he's doing 🙂 |
