The amazing benefits of proper cartridge loading.

[catman]

G'day all. Dlaloum, your modelling is interesting and probably quite valid, but my feeling is that the 'generator' in the 1000? you have and the M97xE are probably substantially different, making the modelling less than totally reliable.

It might be worth obtaining an M97xE body and doing some 'real world' testing with it. This will indicate the validity or otherwise of the modelling. Regards, Felix aka catman.

 

[persil]

I only run MCs and years ago I discovered resistive load matching, I use SUTs from Sowter and I use thier method of resistive matching modified to use a simple multiway rotary switch and some high quality low noise resistors. I use 10 different resistors and adjust the rotary switch to match the cartridge in use. It makes one helluva difference being able to tune the SUTs to the cartridge! Building the thing did cause extra noise at the start but by keeping the leads short, carefull earthing and good shielding soon sorted that out for me. Best thing I have ever done! easy and cheap as well! Sowter transformers explain the principles, give cartridge loading charts and simple wiring diagrams on thier site http://www.sowter.co.uk/specs/9990.htm also the addition of a Zobel network really cleans up the top end on some MCs. I have never used capacitive loading as I dont use MMs. Sowter also supply a twin ratio SUT and combining this with another rotary switch gives me the versitility to run almost any MC cart into my pre amp.

 

[drknstrmyknight]

So where would one start in measuring and tweaking?
i.e. I;ve got a Goldring 1042 on my MMF5.

The sheet says:
Load Resistance 47,000 Ohm
Load Capacitance 150-200pF
Internal Inductance 570 mH
Internal Resistance 660 Ohm

 

[DaveyW]

I see people adjusting the loading with capacitors, and with resistors. I'm just wondering if it would make sense to make a box with two stepped attenuators in it, one wired with resistors (as one normally would do for a volume control), and one wired with sequential capacitor values. In effect, a "loading box" that would allow adjustment of both capacitance and resistance. Short, straight, high-quality wires, solder and connectors would have to be used, since a weak phono signal would be passing through them, and very high-quality attenuators with gold (non-oxidative) contact surfaces, if it were to be left in-circuit.
Any reactions to this idea?

My phono stage offers capacitive loading ops, but I personally prefer the benefits that resistive loading provides.

I have posted before on my approach HERE

And this is the "Loading Box" I use for MM/MI/HOMC's allowing loading adjustment on the fly :yes:

Cheers
Dave

 

[guiller]

Perhaps this article could be a useful addition to this thread: http://www.hagtech.com/loading.html

For example, it gives support to this statement:

This is odd, because while MM Cartridges are affected by capacitance changes, MC Cartridges are not. Mark

MC Cartridges

The super-low self-inductance of a moving coil cartridge puts them in their own category. At such levels, the loading capacitance becomes relatively insignificant, with system bandwidth now dominated by inductance and load resistance.

 

[Dr Tinear]

Perhaps this article could be a useful addition to this thread: http://www.hagtech.com/loading.html

For example, it gives support to this statement:

This is odd, because while MM Cartridges are affected by capacitance changes, MC Cartridges are not. Mark

MC Cartridges

The super-low self-inductance of a moving coil cartridge puts them in their own category. At such levels, the loading capacitance becomes relatively insignificant, with system bandwidth now dominated by inductance and load resistance.

The Grado variable-reluctance (Flux-Bridger) cartridges also have low coil inductance, so the load capacitance has little effect on their frequency response in the audible range.

 

[gip111]

I think the "type" of capacitor would also make a difference in the sound. Just last week I decided to open up my 640p phono preamp and noticed it had some square blue caps in the MM input, I replaced them with equal value mica caps and my Shure M97xe has never sounded better.

 

[voltcontrol]

I think the "type" of capacitor would also make a difference in the sound. Just last week I decided to open up my 640p phono preamp and noticed it had some square blue caps in the MM input, I replaced them with equal value mica caps and my Shure M97xe has never sounded better.

If you didn't know about this thread before, perhaps some extra ideas in here (or some ideas from you for the people there ); http://www.audiokarma.org/forums/showthread.php?t=346388

 

[gip111]

For the past several years I’ve been using a Pioneer SA-9500 II integrated amp for vinyl playback and I have grown fond of it and its ample cartridge loading options (both resistance and capacitance). Lately I’ve been thinking of giving a MC cartridge a try on my Empire/Linn hybrid, so in preparation I purchased an Onkyo P-360RS pre-amp for its MC cartridge capabilities. After servicing the Onkyo I gave her a whirl with my Ortofon OM /200NE cartridge. I immediately noticed much improved detail with this pre-amp V/S the 30 year old 9500 II, however it sounded a little “off” to me. This led me to wonder, just how critical is proper cartridge loading and could that be the source of the problem? With these questions in mind, I set out to learn how to add capacitance to a phono stage. After AK member catman was kind enough to clue me in as to how it’s done, I was off to the races! I bought two RCA “Y” adapters, some cheap male RCA plugs and a small variety of capacitors (51pF, 100pF, 150pF, 200pF, 250pF, 300pF and 350pF). I soldered the caps to the plugs and began to try each cap in successive order until I found the sweet spot. The factory recommended capacitance loading range for Ortofon OM carts is between 200-600pF (depending on the stylus to varying degree). The Onkyo has a factory capacitance loading of 220pF (thanks dr*audio). I found that the Ortofon sounded best to me with an additional 100pF capacitance (a total of 320pF). I’m here to tell you the sonic difference between 220pF and 320pF with this cart is nothing less than amazing to my ears!

This leads me to wonder why I haven’t seen more posts here regarding the importance of proper cartridge loading. I just happened to stumble upon this important adjustment by circumstance; I think it would benefit our members here a great deal if this topic were discussed here more often. What do you guys think?


Bill.

Big Bill....you are the man! I bought two RCA Y adapters and some male RCA plugs. In my case I wanted to use the AT92ECD in my Philips 212 which is a good match but the brightness would make your ears bleed so I used a variety of resistors using this approach till I settled around 10K and the AT92 has never sounded better! Its a great way to "tweak" your cartridge without having to go inside and messing with the phono preamp. Thanks for the tip!