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MM capacitive loading with stock Technics SL-1200GR or SL-1500C

dlaloum

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I guess it depends how loose one's definition of "pretty good" is.

View attachment 259315
The challenge with this, is that to measure the measurement tool..... you need to know where the current cartridge is at (including its loading etc...), the accuracy of the RIAA (assuming the test record is recorded using RIAA !) - and you have to compensate for every step along the way !!!

Running a 33rpm test record at 45rpm can provide some interesting results - and allows for a cross check of whether some of the frequency variations are recorded (In which case they would move due to the increased rotation speed) or due to the replay chain from cartridge all the way through... (but you need to adjust the RIAA parameters to take into account the frequency shift - assuming it is RIAA recorded)
 

JP

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The challenge with this, is that to measure the measurement tool..... you need to know where the current cartridge is at (including its loading etc...), the accuracy of the RIAA (assuming the test record is recorded using RIAA !) - and you have to compensate for every step along the way !!!

Running a 33rpm test record at 45rpm can provide some interesting results - and allows for a cross check of whether some of the frequency variations are recorded (In which case they would move due to the increased rotation speed) or due to the replay chain from cartridge all the way through... (but you need to adjust the RIAA parameters to take into account the frequency shift - assuming it is RIAA recorded)

Of course the measurement has to be competent, which just highlights another issue with the approach should one not be able to figure out how to normalize it themselves - who do you trust?

Work was done years ago to vet pink noise tracks. One record was found to be accurate - CH Precision. Good luck finding copy of that one.

It's just not a good approach to the problem.
 

dlaloum

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Of course the measurement has to be competent, which just highlights another issue with the approach should one not be able to figure out how to normalize it themselves - who do you trust?

Work was done years ago to vet pink noise tracks. One record was found to be accurate - CH Precision. Good luck finding copy of that one.

It's just not a good approach to the problem.
What alternatives are there that are reasonably easy to use?!

Taking a known to be flawed pink noise track, and compensating for the known flaws, seems the easiest alternative!

I have a Dynavector Karat MC - so something with ruler flat frequency response, and no impact from loading... so that takes care of one piece of the puzzle...
Using that I can calibrate for the test record... and then in turn measure a (different) cartridges response, and EQ it to flat.

It is a reasonably effective and not overly onerous process.

And the 33rpm / 45rpm trick can be used to identify various issues so you can compensate for them ... but is a lot more work.
 

JP

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What alternatives are there that are reasonably easy to use?!

Taking a known to be flawed pink noise track, and compensating for the known flaws, seems the easiest alternative!

I have a Dynavector Karat MC - so something with ruler flat frequency response, and no impact from loading... so that takes care of one piece of the puzzle...
Using that I can calibrate for the test record... and then in turn measure a (different) cartridges response, and EQ it to flat.

It is a reasonably effective and not overly onerous process.

And the 33rpm / 45rpm trick can be used to identify various issues so you can compensate for them ... but is a lot more work.

For who? I'm talking about the general advice you gave:

Use a pink noise track (but they're not accurate). They're "pretty good" to 16k and you can verify with other people's measurements (except they're not, and maybe). Then we go in to a diatribe on how measurements can't be trusted and end up that the pink noise track can be compensated against a cartridge you trust. If you're going to that then you don't even need a test track - music will do just fine.

Perhaps another round or two and people will have enough info to make an informed decision?
 

Chester

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Ah, $2500 for the RME ADI-2/4 Pro SE is getting a bit steep!

Point understood, but given it’s German made and the cost it sells for in Europe, you’re getting a pretty decent price.

Take a look at how much Benchmark products sell for in Europe, do the currency conversion and you’ll see my point.
 

mike70

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You can do measurements of the speakers sound with a mic and apply DSP to the system sound as a whole.

Why do you want to apply that complicated method equalizing only the sound of the cartridge?
 

cgallery

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I guess it depends how loose one's definition of "pretty good" is.

View attachment 259315

The CBS records are off as well. The records are really all off.

cartridge_measurements_read-with-care_p2.png
 

JP

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The CBS records are off as well. The records are really all off.

View attachment 259417

None are perfect but this doesn’t tell us anything absolute. I can see that they didn’t apply roll off and shelf to the TRS-1007 which will make it +1dB from about 4k. Difficult to say what other issues existed with this “test”, though we can replicate it. We‘ve already shown some carts to be rather flat using other methods, as you know, so we can piece the data together.
 

cgallery

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Well the #'s are off a chart recorder, and you just the other day mentioned adding a feature to normalize various records to a standard. So I'm going to take the chart recorder output, thanks.

Other attempts at comparing albums seem to confirm differences in test records that would yield clearly audible variations in output:

 

JP

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Well the #'s are off a chart recorder, and you just the other day mentioned adding a feature to normalize various records to a standard. So I'm going to take the chart recorder output, thanks.

Other attempts at comparing albums seem to confirm differences in test records that would yield clearly audible variations in output:


I'm well aware you're going to trust that magazine article over whatever evidence is provided to you. These are things you can easily test on your own if you were so inclined. There is no functionality to normalize records in the script, BTW.
 

cgallery

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I'm well aware you're going to trust that magazine article over whatever evidence is provided to you. These are things you can easily test on your own if you were so inclined. There is no functionality to normalize records in the script, BTW.

It has been tested to death.

To insist the pink noise tracks aren't accurate without acknowledging that the sweeps aren't much better is misleading.
 

JP

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It has been tested to death.

To insist the pink noise tracks aren't accurate without acknowledging that the sweeps aren't much better is misleading.

I don't typically feel the need to boil the ocean on broad subjects when addressing one specific point. No one in this thread was talking about sweep tracks - that non sequitur was yours.

We do have a thread on measuring sweep tracks, if you'd like to comment there. Input is more than welcome as I'd certainly not want the tool to output incorrect data. I'd only suggest that arguments be a bit more substantive than faith-based.
 

cgallery

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I don't typically feel the need to boil the ocean on broad subjects when addressing one specific point. No one in this thread was talking about sweep tracks - that non sequitur was yours.

We do have a thread on measuring sweep tracks, if you'd like to comment there. Input is more than welcome as I'd certainly not want the tool to output incorrect data. I'd only suggest that arguments be a bit more substantive than faith-based.

"Boil the ocean," wow. I didn't realize it was such a burden to mention that the sweeps really aren't much better, when critiquing the pink noise tracks.

Anyways, you stand corrected, good enough for me.
 

JP

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"Boil the ocean," wow. I didn't realize it was such a burden to mention that the sweeps really aren't much better, when critiquing the pink noise tracks.

Said more simply, it's not a burden, it just wasn't relevant to the conversation. Had I said to use sweeps instead you'd have a valid criticism, though I'd never make that blanket statement. And there are sweep tracks that have been checked by other means that do certainly seem to fall within or damn close to their published +/- 1dB specification. I'd say that's considerably better than any pink noise track I can get my hands on.

I look forward to your post in the measurement thread explaining how Scott's method is flawed.
 

cgallery

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Said more simply, it's not a burden, it just wasn't relevant to the conversation. Had I said to use sweeps instead you'd have a valid criticism, though I'd never make that blanket statement. And there are sweep tracks that have been checked by other means that do certainly seem to fall within or damn close to their published +/- 1dB specification. I'd say that's considerably better than any pink noise track I can get my hands on.

I look forward to your post in the measurement thread explaining how Scott's method is flawed.

When discussing the inadequacies of one approach (pink noise), the reader may be left with the impression that the other (sweeps) is somehow immune.

I don't know Scott from Adam, whether his method is flawed or not is irrelevant, this is a garbage-in problem.
 

JP

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When discussing the inadequacies of one approach (pink noise), the reader may be left with the impression that the other (sweeps) is somehow immune.

I don't know Scott from Adam, whether his method is flawed or not is irrelevant, this is a garbage-in problem.

If a reader jumps to conclusions about things that are not being discussed it's on them. If you want to assume that burden, more power to you. Be sure to cover white noise, brown noise, and spot frequencies lest someone conclude those all should be wholly applicable.

A few posts ago it was a method problem, apparently because I'm not using a chart recorder. Good to know we're past that. Are you still contesting that the TRS-1007 records and STR 100 records I have here can't measure as close as they do?
 

cgallery

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If a reader jumps to conclusions about things that are not being discussed it's on them. If you want to assume that burden, more power to you. Be sure to cover white noise, brown noise, and spot frequencies lest someone conclude those all should be wholly applicable.

A few posts ago it was a method problem, apparently because I'm not using a chart recorder. Good to know we're past that. Are you still contesting that the TRS-1007 records and STR 100 records I have here can't measure as close as they do?

Or someone could just point-out the same pitfalls apply to the other commonly used approach. It is a discussion forum, after all.

And I only said that I'll take the JH results via the chart recorder, over yours, and that is unchanged.
 

JP

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Or someone could just point-out the same pitfalls apply to the other commonly used approach. It is a discussion forum, after all.

And I only said that I'll take the JH results via the chart recorder, over yours, and that is unchanged.

They sure can. And no amount of verifiable data to narrow those broad brush strokes should ever stop them.
 

dlaloum

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For who? I'm talking about the general advice you gave:

Use a pink noise track (but they're not accurate). They're "pretty good" to 16k and you can verify with other people's measurements (except they're not, and maybe). Then we go in to a diatribe on how measurements can't be trusted and end up that the pink noise track can be compensated against a cartridge you trust. If you're going to that then you don't even need a test track - music will do just fine.

Perhaps another round or two and people will have enough info to make an informed decision?
A simple solution for EQ to an adequate level that will provide close to flat F/R with minimum fuss...

Use a pink noise track, and some easy to use EQ software (bundled with products like the RME ADC/DAC)

Results: consistent, repeatable frequency response within the limits of the tools used - in most cases the end result will be within +/- 1 to 2 db up to 15kHz... which is far better than can be achieved with most cartridges and the MM loading... (without getting fancy with measurement and calculations).

It is my recommendation as the easiest to use consistent adjustment method.

If you want to get more precise, more accurate, or you want to extend the frequency range over which you want to work... all of that can be done - and there are levels of difficulty, and levels of OCD, required to go further.
 
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