Frequency Response Test Records

[Balle Clorin]

So now we know it the first original that has the blip at 12k, and Issue 2 that has no blip, but a possible drop in one channel . I will test my issue 2 this weekend.

 

[Balle Clorin]

Here is the SFC-TR100 Issue 2
no blip at 13khz!!!

strangely my cartridge blip at 9k did not occur on the very first run, but came back on the second, that blip has been there for ever and every test record, and then it goes undetected once??
'

It is time to retirE the worn 1A track on my CA TRA-1007..

 

[Thomas_A]

check it with REW and I think you see the blip.

 

[mackat]

Which version in yours? Issue 2?
View attachment 524801

Mine is not Issue 2

 

[Balle Clorin]

check it with REW and I think you see the blip.

No..very strange that the blip was not detected in a single instance,

Mahbe the POP a bit higher in frequency ubscured it in som way..
Same track with and without 9khz blip, same record same system same hour

 

[mackat]

Mine is not Issue 2

Whoops, I was mistaken. Mine is indeed Issue 2. It says it on the record, but not on the sleeve.

 

[Balle Clorin]

it makes sense then Issue 2 has less blip

 

[aaaakkkk]

it makes sense then Issue 2 has less blip

Are the matrix numbers different for the first and second pressings?

 

[Balle Clorin]

Issue 1 ( unmarked) has 5 tracks on side A and a number on A of OS -2851LB on label and OS -2851LB N3 on the run out matrix

Side B OS -2852B with N1 added on the matrix/run out

Issue 2 has 6 tracks on side A and no run out matrix number visible.

Side B has a matrix number OS-2852LM H2

 

[aaaakkkk]

I'm very interested in what crosstalk above 10 kHz is recorded on the test records, but the mechanical resonance of this cartridge prevents me from measuring it, so to get around this, I decided to try the 16.66 RPM speed.

Audio Test Record - Technics SFC-TR100
Cartridge body - AT-540
Stylus assembly - AT440MLa (~20hrs)
Turntable - Sony RS-LХ300H
VTF 2.0 grams
Tracking ability ~100 µm



1 - 33,33 Rpm Vertical tracking angle: 22.5° SRA-92.5°
2 - 16,66 Rpm Vertical tracking angle: 22.5° SRA-92.5°
3 - 33,33 Rpm Vertical tracking angle: 21° SRA-91°
4 - 16,66 Rpm Vertical tracking angle: 21° SRA-91°

 

[Balle Clorin]

How did you measure the VTA?

How can the frequencies go to 20k at 16 rpm when it stops at30 at 33?

 

[solderdude]

I still find it funny that even the most mundane DACs around literally perform more than a 100x to 1000x 'better' than vinyl.

It shows how 'poor' the hearing is what concerns 'sound quality' as vinyl sounds more than good enough for most folks.

 

[aaaakkkk]

How did you measure the VTA?
,
How can the frequencies go to 20k at 16 rpm when it stops at30 at 33?

I took separate photos of the cantilever, the diamond, and the diamond contact line. The recording speed was 16.66 rpm; then, it was increased to 33.33 rpm in Adobe Audition.

 

[aaaakkkk]

I compared the Ortofon Test Record at 16.66 rpm and 33.33 rpm, then selected the best result from the three Ortofon test discs.

Audio Test Record - Ortofon Test Record
Cartridge body - AT-540
Stylus assembly - AT440MLa (~20hrs)
Turntable - Sony RS-LХ300H
VTF 2.0 grams
Tracking ability ~100 µm

 

[aaaakkkk]

I compared CA-TRS1007 (Side A) at different VTA angles ranging from 17° to 27°.
The tests were performed at 16.66 RPM.

Audio Test Record - the CA-TRS1007 side-A
Cartridge body - AT-540
Stylus assembly - AT440MLa (~20hrs)
Turntable - Sony RS-LХ300H
VTF 2.0 grams
Tracking ability ~100 µm

 

[Balle Clorin]

Very interesting. Hard to see any difference,I think maybe modulation level is too low to show harmonic distortion effects. Intermodulation distortion reveal VTA differences better, ( DiN 45 542 and CBS STR-112)
The wavy distortion pattern is interesting, possibly a once per revolution warp or off center thing?

 

[Thomas_A]

Yep interesting.

The crosstalk differs around 5 dB, but do not go much below 25 dB. The high frequency differs a bit too, but not much. A pity you did not check the distortion from the vertical 1 kHz track at the same time.

And is this MLa a microfine? Does look more like a hyperelliptical/fine line. Edit: I see now the angle was not the one I thought...

 

[Thomas_A]

Just want to post a comparison of the CA-TRS1007 and the Ortofon with @JP correct adjustment of the Ortofon error (my previous was not the correct one, and the correct is below). My Shure V15V with the recent JICO stylus, VTA shimmed 6°. Crosstalk difference is the issue...and mystery. Previous stylus same shim had the opposite result.

CA-TRS1007

Ortofon:

The Ortofon correction:

Step 1: RIAA
(setf *track* (biquad-m *track* 7.9682567668766300E+00 -5.2724672933908900E+00 -1.4469430767688700E+00 1.0000000000000000E+00 3.6557310000000000E-01 1.4996620000000000E-02))
(biquad-m *track* 1.10057904093330000E+00 -6.65301031771105000E-01 -4.30266896696176000E-01 1.00000000000000000E+00 -5.75527420000000000E-01 -3.79604780000000000E-01)

Step 2: shifted constants (due to wrong constants at cutting half speed)
(biquad-m *track* 0.73137993061956 -0.39063797071820 -0.27569578143734 1.0 -0.59106473412185 -0.39977762693709)

 

[JP]

If those are “my” coefficients it’s not a double filter, rather shifted constants.

 

[aaaakkkk]

Yep interesting.

The crosstalk differs around 5 dB, but do not go much below 25 dB. The high frequency differs a bit too, but not much. A pity you did not check the distortion from the vertical 1 kHz track at the same time.

And is this MLa a microfine? Does look more like a hyperelliptical/fine line. Edit: I see now the angle was not the one I thought...

This is 100% a MicroLine stylus. Do any other diamonds even have this kind of shape? However, this MicroLine isn't perfectly symmetrical: its edges have different lengths and thicknesses, and I think the angles of the edges are different too. And I still don't understand why the crosstalk is so poor, only 25 dB. Maybe this record was cut with an SRA of 15 degrees or less."