go to vinylengine.com
find and click on "database" towards the top
click on tonearms/find your tonearm and write it down its specs or print
back button till your back to vinylengine.com
click on database again and click on "cartridges"
search and find the specs of your cartridge and write it down/print
enter numbers in the calculator
hit calculate and you have done the first steps for practice
yes Bill
I said on the last line "hit calculate and you have done the first steps for practice" without defining terms
would you mind defining cartridge compliance and why your quoted statement above is true?
we can get to effective mass/cartridge weight and the other stuff later
To measure 10Hz compliance you adjust tonearm effective mass until it resonates at 10Hz. Or take a known effective mass and measure the resonant frequency and read compliance off a graph. There is no other accurate way to do it. And you have to trust the tonearm manufacturer effective mass spec.
PHONO Cartridge Compliance, Tonearm Mass, System Resonance, Loading of MC and MM Capacitance, RIAA Characteristic
the above would be a good place to start Carl and would be the whys before it starts getting complicated ( I started this thread to learn more too)
My previous re-directs were for beginners to lay some ground work.
Please see the one below as a next step:
The Compliance of a Cartridge and the Resonant Frequency of the Tonearm/Cartridge Combo
No it isn't all the info we need, but we are getting closer to being able to compare stuff.
Please see the one below as a next step:
The Compliance of a Cartridge and the Resonant Frequency of the Tonearm/Cartridge Combo
No it isn't all the info we need, but we are getting closer to being able to compare stuff.
Hmmm were that it be so simple.....
The term 'compliance' means different things to different manufacturers. Although expressed in physical units as though a spring, usually it is a restatement of mechanical impedance but expressed as though a spring.
Really, mechanical impedance at the pointy end is a complex quantity. At 10Hz impedance is mostly spring, at 100Hz mostly damping, and at 10kHz mostly mass. All are important and present in different quantities between cartridges. There is no reliable way to convert.
Spring dominates LF, damping midF, and mass Hf trackability for a given VTF. Put another way, if yer want a certain trackability compliance simply tells yer what VTF to use.
As to cart-arm as a spring-mass system, actually it's a spring-mass-damping system. The elephant in the room is how much damping is present because generally mostly that comes from cartridge elastomer. The main effect is to stabilise the cart-arm resonance, which is the most important role sonically. Avoiding FM modulation at say 10Hz, as well as helping trackability.
Anyways, noble stuff and HTH in some small way.
LD
The term 'compliance' means different things to different manufacturers. Although expressed in physical units as though a spring, usually it is a restatement of mechanical impedance but expressed as though a spring.
Really, mechanical impedance at the pointy end is a complex quantity. At 10Hz impedance is mostly spring, at 100Hz mostly damping, and at 10kHz mostly mass. All are important and present in different quantities between cartridges. There is no reliable way to convert.
Spring dominates LF, damping midF, and mass Hf trackability for a given VTF. Put another way, if yer want a certain trackability compliance simply tells yer what VTF to use.
As to cart-arm as a spring-mass system, actually it's a spring-mass-damping system. The elephant in the room is how much damping is present because generally mostly that comes from cartridge elastomer. The main effect is to stabilise the cart-arm resonance, which is the most important role sonically. Avoiding FM modulation at say 10Hz, as well as helping trackability.
Anyways, noble stuff and HTH in some small way.
LD
Would a test record help to calculate effective mass?
IIUC, ideally you want the arm resonance to be 8-10 Hz so I am wondering if there is some way of determining this with a sweep and a A-D input on a sound card directly in from the cart since a lot of phono amps roll off below 20-25 Hz.
I have a DL103 on an SME 3009 Series II and have been led to believe its not a good combo because the arm<>cart resonant frequency is too high. I got a figure of 16Hz, but given @billshurv's comments, would not know if this is correct. My phono amp has a 40 dB/decade filter, but I guess the issue that concerns arm resonance is with tracking.
I looked on eBay and see you can buy additional weights that you attach to the back of the arm and you then add some weight at the cart end to lower the resonant frequency. I balked at the prices (£76 I saw one for) not knowing if it was the right thing to do or not.
I am a complete novice on the mechanical stuff (most other stuff as well I have admit as well
)
IIUC, ideally you want the arm resonance to be 8-10 Hz so I am wondering if there is some way of determining this with a sweep and a A-D input on a sound card directly in from the cart since a lot of phono amps roll off below 20-25 Hz.
I have a DL103 on an SME 3009 Series II and have been led to believe its not a good combo because the arm<>cart resonant frequency is too high. I got a figure of 16Hz, but given @billshurv's comments, would not know if this is correct. My phono amp has a 40 dB/decade filter, but I guess the issue that concerns arm resonance is with tracking.
I looked on eBay and see you can buy additional weights that you attach to the back of the arm and you then add some weight at the cart end to lower the resonant frequency. I balked at the prices (£76 I saw one for) not knowing if it was the right thing to do or not.
I am a complete novice on the mechanical stuff (most other stuff as well I have admit as well
)
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My method is to play a silent track and look at the spectrum. If you get a 16Hz peak, that is likely to be the Fres. I've not tried seperating vertical and horizontal from that as these are likely to be different.
But personally I would see 16Hz as livable with. There is little to no music that will stimulate that and it's easily damped with an FD200. But people have had success from 6Hz up so go figure.
But personally I would see 16Hz as livable with. There is little to no music that will stimulate that and it's easily damped with an FD200. But people have had success from 6Hz up so go figure.
Thanks Bill.
Another 2p worth is IMHO the Resf doesn't matter per se. More important is overall stability. Given that damping is finite and fixed yer get more stability from choosing an arm with a higher Resf. However too far starts to impact LF response in the audio band.
Another 2p adds that the resonant system is continuous in 2D, so the path of the arm in response to a 'displacement event' might be on any vector or even a curve...there isn't really discrete lateral or vertical resonant systems per se.
LD
Another 2p worth is IMHO the Resf doesn't matter per se. More important is overall stability. Given that damping is finite and fixed yer get more stability from choosing an arm with a higher Resf. However too far starts to impact LF response in the audio band.
Another 2p adds that the resonant system is continuous in 2D, so the path of the arm in response to a 'displacement event' might be on any vector or even a curve...there isn't really discrete lateral or vertical resonant systems per se.
LD
Thank you guru LD
It does help a lot when you send a padawan back to their pen/paper/chalkboard/pictures and dictionary
Questions to follow latter if you don't mind
I am a complete novice on the mechanical stuff (most other stuff as well I have admit as well
Join the crowd
Please read the URL in post # 11 and re-do your calcs
Read this also :
http://www.cieri.net/Documenti/Misu...esonances in Turntables (AN17-233 - 1977).pdf
It implies that 15hz is good
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