What is the internal resistance or source impedance of the Hana SL?
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30 ohms is pretty high for a cartridge of that output. At 100 ohms loading you’ll lose around 2.28 dB of signal in theory (relative to infinite ohms "no loading"; and about 1.65 dB down relative to the recommended 400 ohms loading, again in theory) and will start to induce some frequency response deviations from flat. But it will work, and only you can say whether you’ll like the effect.
As mulveling says, you will lose some output signal voltage at 100 ohms load, but also you will lose some extreme high frequency response. The cartridge may sound a bit dull and rolled off with that load and a source impedance of 30 ohms, besides the penalty in over all gain. However, it should be no big deal to change the load resistance afforded by your phono input, unless it uses an SUT to boost gain, in which case it gets a bit more complicated, but still not un-fixable.
I have a Hana EL which is basically the same thing specwise.I bought this from dB Systems: https://store.acousticsounds.com/d/60044/DB_Systems-DB_Systems_DBP-6_MC_Phono_Resistor_Loading_Kit-T...They will provide it with any value you want. I got one for 400 ohms and it works great.That being said, it didn't sound bad at 100 ohms either.
My old dealer sold me one of those DB-Systems kits when I first got into vinyl, ~ 11 years ago. The adapter cable & plugs/jacks are very plain, and won’t satisfy anyone with audiophile nervosa and 4 or 5-figure cables, but the kit is very handy and it’s fun to play with the different loading values! If nothing else, it can help you hone in on the optimal loading for a cartridge before you explore more hard-wired loading solutions with exotic resistors. But I used ’em patched in full-time with my first Benz Glider and later an Ortofon Kontrapunkt "c", to good effect. Good to know they still make ’em.
The kit could use a few more values above 200, up to at least 1K, though. Right now it’s pretty much focused on low-output MC’s with less that 15 ohms coils. And that 10 ohms (or even 20 ohms), I can’t imagine ever using.
The 100-ohm load will not sound "bad" with these cartridges, either the SL or the EL, but the SQ will be colored to a degree by the effect of the load resistance on the HF response and on total gain. It’s OK to like it that way. Lots of guys load down the Denon DL103, which has a similarly high internal resistance, even below 100 ohms, and claim to love it.
But it should be a simple matter for any competent tech to open up the chassis of a phono stage and replace the phono load resistor with a more appropriate value. I would suggest 1K ohm and forgeddaboudit. If the LOMC gain is being generated via an SUT, then one trick would be to increase the value of the load resistor that is across the secondaries of the SUT, to a value that results in the desired higher impedance being seen at the primaries. For that, the tech would need to obtain information about the turns ratio of the SUT, as well, from the maker of the phono stage.
"The kit could use a few more values above 200, up to at least 1K, though. Right now it’s pretty much focused on low-output MC’s with less that 15 ohms coils. And that 10 ohms (or even 20 ohms), I can’t imagine ever using."
If you contact dB directly, they will provide the kit with whatever values you want.
I use lots of carts so I can't hard wire any exotic resistors. Would be curious if I could hear any difference though!
thanks to all for the suggestions.I am reluctant to ad another " interconnect" between the phono cable and the phono preamp (all tube with SUT) in case it degrades the SQ but perhaps I am being too picky.I was wondering how do you make the calculation of loss of output based on the cartridge impedance?
1. add up the coil ohms plus loading ohms, e.g. 30 + 100 = 130
2. divide the loading ohms by the number from step 1, e.g. 100 / 130 = 0.769
3. take the log (base 10) of the result from 2. and multiply that result by 20; that number represents the loss in dB versus a theoretical load of infinite resistance (i.e. NO load on the cartridge), e.g. 20 * log10(0.769) = -2.2788 dB
Calculate loss for other loading values and subtract them to determine relative losses.
Did you end up buying the cart? I hope you did. I've had mine for two months and it's glorious. I'm puzzled by what I've read here though. You said your "audiophile nervosa" has got you at 4 and 5 figure cables, wouldn't a Lyra, Van den Hull, Dynavector or a Soundsmith or at least Hana's own ML model be more appropriate in such a system? Good luck
Loading is entirely for the benefit of the preamp not the cartridge. Here's how it works:
The cartridge is an inductor. The tone arm cable has a capacitance. Since they are in parallel, the result is a tuned resonant circuit, often active at +100KHz frequencies or even into the MHz range.
If your preamp isn't happy with radio frequency energy coming in (and that is what I'm talking about) then the loading is used to detune the resonance and thus kill the RFI (Radio Frequency Interference).
It is therefore non-critical- a low enough resistance value is all that's needed if your preamp can't handle RFI (and if it has a switch for loading on the front panel then that is the case).
I would try it without any loading and see how it sounds though! The load causes the cartridge to do more work and thus makes the cantilever more stiff and less able to trace higher frequencies.
I find the reasoning behind the loading kits like DB Systems, at the least, questionable. If my phono pre or SUT has a fixed input loading of 100 ohms and I add a 300 ohm resistor in parallel, what is the resulting load impedance? Hint: it sure ain't 400 ohms as is widely believed.
FWIW, I run my Hana SL into a SUT with a fixed input load of 100 ohms and it sounds excellent.
Chili, I think you are underestimating the technical expertise of the designer at DB Systems. The kits are meant to be used in conjunction with a phono stage that has a fixed input resistance of 47K ohms. For other fixed input resistances, I suppose they can provide custom values, but as you intimate, the final net resistance of two or more resistors in parallel can never be higher than that of the lowest value resistor in the parallel grouping. Most audiophiles know this, let alone all EEs. I don't think it's "widely believed" that resistances in parallel are additive.
By the way, SUTs cannot have a "fixed" input impedance. Transformers do not per se have an impedance. The device on the primary side sees an impedance equal to that of the device on the secondary side divided by the turns ratio of the transformer. I guess you know all this, but your post makes me wonder what load you are presenting to your Hana. For the Hana to "see" a load of 100 ohms, using a SUT with a 1:10 turns ratio, the resistance on the secondary side must be 10,000 ohms. Is that the case? If the turns ratio is other than 1:10, then take the square of that turns ratio and multiply it by 100 ohms to find the value of the resistor on the secondary side, at the input of the phono stage, which would give a 100-ohm load to the Hana.
On paper, 100 ohms should not be optimal for the Hana SL, with its internal resistance of 30 ohms, but you like what you like.
>I think you are underestimating the technical expertise of the designer at DB Systems.
>The kits are meant to be used in >conjunction with a phono stage that has a
>fixed input resistance of >47K ohms.
Then I wonder why @andysf suggested them as a remedy in response to the original post which asks:
>My own phono stage only allows 100 ohms
>for MC cartridges-as do many others.
>Has anyone tried the Hana at 100 ohms and were you
>happy with the result?
>I have a Hana EL which is basically the same thing specwise.
>I bought this from dB Systems...etc...
Surely, neither you nor @andysf propose plugging a Hana SL into a normal 47kohm MM phono input and adding loading plugs. I tried my Hana SL direct, that is, without a SUT, one time and the sound was thin and lacked dynamics. I could hardly wait to remove it!
>For the Hana to "see" a load of 100 ohms, using a
>SUT with a 1:10 turns ratio, the resistance
>on the secondary side must be 10,000
>ohms. Is that the case?
No. My Rothwell MCL SUT is resistor loaded. https://i.ebayimg.com/00/s/MTIwMFgxNjAw/z/8r0AAOSwYXVYya~I/$_57.JPG?set_id=8800005007