Introducing the Phono Cartridge Measurement Library

[narud]

Audio Technica AT-120E (later version with nude .3x.7 elliptical)

picked this up cheap and the diamond looks nearly unused. tip is still round from front view and contact points still look like tiny dots. The generator on these is always a question to me. This version is supposed to be 490mh and it measures 560/590mh. one of my vm540ml bodies measures 510/530mh and its supposed to be 460mh. my 150sa measures closer to what it's supposed to at 480mh. my shure carts all measure close to their published spec so i dont think its an issue with the meter. is this just manufacturing tolerance?

I listened to some music first before measuring and i could tell this puppy was going to measure bright. interesting was the dual resonance. ive seen that before when i transferred an the cantilever assembly from a vm95en to a carrier for this series of bodies. i assumed it was an effect from the transfer, but it happens here too. these nude diamonds at is using for their nude .3x.7's look pretty crude and unpolished compared to the nude ogura ortofon uses. i wonder where these are coming from? my at122ep, vm95en and this guy all look like this.

I also measured a nos 125lc stylus on this that i dont have a matching body for. theyre supposed to use the same body, but the high inductance on this sample makes me curious. the 125lc is a much more listenable stylus.

Audio Technica AT125LC stylus on 120e body

 

[richjoh]

Nagaoka MP150 cartridge
Schitt Mani2 phono preamp 47KOhm, 47pF with Rp 156K Ohm and Cp 31pF
Technics 1200 MKIII turntable
CBS STR-120 (Issue 2)

My CBS STR-100 test data never measured good. Although the vinyl was "new sealed", I got bad result.
I then found a CBS STR-120 (first release) it got much better results compared to STR-100 but there were a few scratches.
Gambled and lucky on a second purchase of the CBS STR-120 which was an "Issue 2" release. Pressing has some scratches but improvement appears to be on the test signals quality and timing (short 1kHz between test signals).

The Nagaoka MP150 requires parallel R and C to flatten the peaking near 20kHz. When I tested the Nagaoka MP200 it flatten out without adding additional parallel R C.

 

[richjoh]

Nagaoka MP200 cartridge
Schitt Mani2 phono preamp 47KOhm 194pF
Technics 1200 MKIII turntable
CBS STR-120 (Issue 2)

Was able to flatten the response with Schitt Mani2 by selecting "In" 47pF, "In" 100pF for a total 194pF.

 

[narud]

Nagaoka MP150 cartridge
Schitt Mani2 phono preamp 47KOhm, 47pF with Rp 156K Ohm and Cp 31pF
Technics 1200 MKIII turntable
CBS STR-120 (Issue 2)

My CBS STR-100 test data never measured good. Although the vinyl was "new sealed", I got bad result.
I then found a CBS STR-120 (first release) it got much better results compared to STR-100 but there were a few scratches.
Gambled and lucky on a second purchase of the CBS STR-120 which was an "Issue 2" release. Pressing has some scratches but improvement appears to be on the test signals quality and timing (short 1kHz between test signals).

The Nagaoka MP150 requires parallel R and C to flatten the peaking near 20kHz. When I tested the Nagaoka MP200 it flatten out without adding additional parallel R C.

View attachment 499219

i may be misinterpreting, but are you adding 156k resistors to drop the 150's load down to 35k but the heading of your graph is stating the settings of the preamp?

 

[richjoh]

i may be misinterpreting, but are you adding 156k resistors to drop the 150's load down to 35k but the heading of your graph is stating the settings of the preamp?

That is correct. I did a lot of swapping R, C and preamp dip switches. I describe each setting separate.

 

[USER]

That is correct. I did a lot of swapping R, C and preamp dip switches. I describe each setting separate.

It would be helpful (and it is strongly encouraged) that your primary graph is of a normal load, whatever it may be. Esoteric loading is not very helpful for our members that want to know performance under normal and replicable conditions, though as supplementary data, the results are very cool.

As of now, I am not sure if there are any comparisons between STR-100 and 120 here so I have no idea how the latter compares to our standard JVC/CA TRS-1007, which are known to be "flat." Perhaps JP has tested the record. This data would be helpful on your quest for optimization. If you are interested see my first measurement of the Shure V15 VMR for a comparison between CA TRS-1007 and CBS STR-100.

 

[narud]

It would be helpful (and it is strongly encouraged) that your primary graph is of a normal load, whatever it may be. Esoteric loading is not very helpful for our members that want to know performance under normal and replicable conditions, though as supplementary data, the results are very cool.

As of now, I am not sure if there are any comparisons between STR-100 and 120 here so I have no idea how the latter compares to our standard JVC/CA TRS-1007, which are known to be "flat." Perhaps JP has tested the record. This data would be helpful on your quest for optimization. If you are interested see my first measurement of the Shure V15 VMR for a comparison between CA TRS-1007 and CBS STR-100.

has anyone done laybacks of the clearaudio vs jvc? you guys have a way longer history with this so im sure ive missed a ton. i know its supposed to be a copy of the jvc but the inner sweeps show way more roll off than the jvc right?

 

[USER]

has anyone done laybacks of the clearaudio vs jvc? you guys have a way longer history with this so im sure ive missed a ton. i know its supposed to be a copy of the jvc but the inner sweeps show way more roll off than the jvc right?

I'm sure JP has but I can't find them. Here's his comparison between JVC and CBS and my comparison between CA and CBS from the early days of the script. Scale is different and set-ups are different (lol) but back then it seemed remarkably similar to me. I do think you are right in that in inner sweeps are different, though also possibly in different sections of the record.

Phono Cartridge Response Measurement Script

6 150MLX bodies including yours: 352/364 354/358 352/350 360/363 304/333 346/354 150MLX inductance

www.audiosciencereview.com

 

[richjoh]

It would be helpful (and it is strongly encouraged) that your primary graph is of a normal load, whatever it may be.

Not sure what you mean by “normal load”. Is that in regards to additional R and C for the Nagaoka MP150? Or does it have to do with the dual plot selection vs single plot? Or something else altogether.

 

[USER]

Not sure what you mean by “normal load”. Is that in regards to additional R and C for the Nagaoka MP150? Or does it have to do with the dual plot selection vs single plot? Or something else altogether.

If I am understanding correctly, you added a resistor to the circuit? Separate from the phono stage switch settings? If so, we would count that as customized loading. If it is all done via the phono preamp switches then I would consider that a normal load. So again, if I am understanding correctly I would count your MP200 graph as a normal load graph and your MP150 graph as a supplemental one.

If STR-120 is anything like STR-100 you would want to reduce capacitance by about 50pF to compensate for the boost between 5-12kHz under a 47k load when compared to JVC/CA TRS-1007. But, again, that is assuming it isn't "flat."

 

[deniall83]

Has anyone measured the effects of different headshells? Assuming tracking weight is set the same, would a heavier headshell have a different effect on a cartridges performance than a lighter one?

 

[richjoh]

So again, if I am understanding correctly I would count your MP200 graph as a normal load graph and your MP150 graph as a supplemental one.

If STR-120 is anything like STR-100 you would want to reduce capacitance by about 50pF to compensate for the boost between 5-12kHz under a 47k load when compared to JVC/CA TRS-1007. But, again, that is assuming it isn't "flat."

Thanks for clearing up my question. If a cartridge compensation doesn't equalize/flatten the response, I see no use for the info. The Nagako MP150 results appear in other post with normal loads, the post was of no interest due to the result. Maybe a field should be added to the plot for supplemental loading values. I'll label the compensation should I post again.

Again, I think my copy of CBS STR100 was just a "bad" pressing. Right channel persisted 1-2dB below the left. The CBS STR100 HF cutoff is 20KHz, where the resonance of MM cartridges peak. CBS STR120 HF cutoff is 50KHz showing stop band of MM cartridges.

I'm now testing a MC cartridge where its peaking occurs out to 40KHz but also effecting 12KHz.

 

[narud]

Thanks for clearing up my question. If a cartridge compensation doesn't equalize/flatten the response, I see no use for the info. The Nagako MP150 results appear in other post with normal loads, the post was of no interest due to the result. Maybe a field should be added to the plot for supplemental loading values. I'll label the compensation should I post again.

Again, I think my copy of CBS STR100 was just a "bad" pressing. Right channel persisted 1-2dB below the left. The CBS STR100 HF cutoff is 20KHz, where the resonance of MM cartridges peak. CBS STR120 HF cutoff is 50KHz showing stop band of MM cartridges.

I'm now testing a MC cartridge where its peaking occurs out to 40KHz but also effecting 12KHz.

labeling the graph so it shows that its loaded at 35k would be super helpful. as is, its kind of confusing.

my copies of the 100 show a channel imbalance that doesnt show up with pink noise from the hifinews record. i just normalize all the results i post since im primarily concerned with frequency response and the 100 is a known quantity.

 

[richjoh]

labeling the graph so it shows that its loaded at 35k would be super helpful. as is, its kind of confusing.

Well, the graph is labelled, look at the bottom left corner where the Rp (resistance parallel) and Cp (capacitance parallel) are spelled out. Hey, I have to track this stuff for my own use since I have multiple cartridges and multiple phono preamps.

I noticed some users doesn't always fill in the information in all the fields when posting. There should be information at the bottom left/right of the plot.

 

[narud]

Well, the graph is labelled, look at the bottom left corner where the Rp (resistance parallel) and Cp (capacitance parallel) are spelled out. Hey, I have to track this stuff for my own use since I have multiple cartridges and multiple phono preamps.

View attachment 499589
I noticed some users doesn't always fill in the information in all the fields when posting. There should be information at the bottom left/right of the plot.

everyone ive seen here use non standard loading states in the bold heading of the graph. the average reader isnt going to make the conversion to figure out what load that measurement is at.

 

[JP]

I noticed some users doesn't always fill in the information in all the fields when posting. There should be information at the bottom left/right of the plot.

The field hints on the form show what we want to see. We do not want to see loading info on that field as it's expected that the actual load the cartridge sees is in the title field. I believe these standards are spelled out in one of the first few posts in this thread. The way you're doing it goes against this standard and requires explanation. Use the tool however you want, but @USER does ask for consistency in how the meta fields are used for plots in this thread. At the end of the day we should at least not confuse people.

If it is all done via the phono preamp switches then I would consider that a normal load.

I'm not sure this really matters as there's no standard in loading options phono stages may provide. I do agree that I prefer to see a "nominal" load plot even if we have several as that allows a determination on whether the setup used is reasonably accurate or not.

 

[dlaloum]

Has anyone measured the effects of different headshells? Assuming tracking weight is set the same, would a heavier headshell have a different effect on a cartridges performance than a lighter one?

Yes.

Keep in mind that tracking force is different from the effective inertia of the arm. ie: the VTF is a completely seperate variable from the effective mass.

You can adjust the effective mass of the arm by varying headshells - I have used headshells with weights varying from 5g to 22g - that is a very very wide variance (further exacerbated by the huge variance between the lightest and heaviest cartridges!)

The effective mass of the arm will interact with the compliance/damping of the cartridge cantilever suspension, and the resulting low frequency resonance is a critical factor in the performance of the system...
Too low, and it will amplify/maximise footfall and environmental vibrations (in the 2Hz to 5Hz range), too high and it will directly impinge on the audible low frequencies... ideally we try to get that resonance balanced at around 10Hz... even better if possible we then try to damp that resonance while minimising the negative impacts of damping on the free motion of the arm/cantilever/needle (this being achieved by inherent damping by the cantilever suspension material, plus damping in the arm mechanism where fitted)

If the arm has damping (fluid, electro-magnetic, magnetic, or other...) the overall system can in many cases accept resonant frequencies lower & higher than the ideal 10Hz - allowing for greater flexibility in cartridge selection/matching.

Other notes: you can adjust the effective mass by using higher mass headshells, but you can easily reach the point at which the counterweight is no longer heavy enough (or light enough - depending which way you are going!) to allow for proper balance and VTF adjustment ... so for the ultimate flexibility you need to be able to exchange not only headshells, but also counterweights.
As a handy note, there are a wide variety of vintage arms/counterweights that use the same arm diameter - making them interchangeable... with some searching in spare parts boxes, you may be able to put together a small selection of counterweights to allow for maximum flexibility!

So short form answer to your question:

Measurable effects of differing headshells...

1. Varying Mass (resulting in varying resonance frequency)
   1. this is the greatest impact by an order of magnitude
   2. Typically overlooked and misunderstood - c.f. Effective Arm Mass
2. Varying internal resonances (ie: small internal resonances within the structure of the headshell/cartridge)
   1. By order of magnitude this impact is very small - often not easily measurable
   2. Outsize claims are made for this, although it does exist, actual claims frequently meander into the domain of "snake oil"
3. Bling / Feel / Quality
   1. There are some superbly crafted headshells, and there are cheapie "junkers"
      1. It is always lovely to use a well crafted product
      2. No objective advantage to well crafted
   2. Occasional quality advantage
      1. Well centered/positioned mounting
      2. Mountings that don't "slip"
      3. etc...

 

[mackat]

AT33xMLB

Curiosity got the best of me

There's a ~0.75 dB channel imbalance, but I think the normalized plot makes more visual sense here.

It has a much sharper resonance than the typical AT33PTG/II and even OC9XML.

One AT33PTG/II I bought last year did look somewhat similar to this, but it seemed to be an outlier.

The one song I've listened to with it so far sounded nice!

 

[Balle Clorin]

Nice, any crosstalk results from Ortofon or Analog Production Ultimate test record?
High resonance peak 4db!! But would compensate for some age related hearing loss

 

[VinyLuke]

DENON DL-305

Notes:

• Cartridge is used and unmodified, hours unknown
• Turntable: Technics SL-1210GR with KAB Fluid Damper
• VTF: 1.20gr
  • Capacitance: ~105pF (total capacitance)
  • Loading: 406Ω
  • A/D: TASCAM US-2x2HR and Audacity
• Test record: Clearaudio CA-TRS-1007 side B