• Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Script for intermodulation distortion testing of vinyl playback, setting VTA ,Zenith etc by test record

Hmm strange..

I get rev21=21.48, original web app=REV19= 22.70

Can you share the wav file?


Web app rev21
1784834142179.png



Python rev 21
1784834196178.png


REV19 =original web app
1784834261928.png
 
Last edited:
Balle Clorin said:
recorded with RIAA?
Click to expand...
Yes.

Tested with RIAA inverse, no significant difference. Also other files that I have. Can't replicate your findings.
 
Last edited:
Claude explains that versions prior to rev21 got VTA calculation polluted by tracing distortion, rev 21 has a more correct implementation and is “insensitive “ to tracing distortion. ( the whole point in the patent is to separate tracing from tracking distortion- quite annoying the at Claude missed that fundamental part from the start)
So stylus/recordings with low inherent tracing distortion will show little difference in VTA for Rev19 vs rev21, like Thomas file. For cases with higher inherent tracing distortion VTA result can be affected in Rev 19 but not Rev21, thus showing more different results.

I hope Claude is correct about this now.
 
Last edited:
Not really trusting Claude. Seems to come up with explanations ad hoc.
 
Yes it is not free from Hallucinations, but I am not a Python coder or vinyl mathematician, so bugs will appear and slip past me,. Getting more data and asking critical questions is the way I have to improve/debug the code. we are now up to rev 22( recoded angle waring which was obviously false)- the web app was started at REV19
(I will spare you from the whole excuse Claude gave)

the current code rev 22 is given below. If someone wants to check it manually against the references , here is the chance ;)

PS could you please share a recording of the whole Side B of CBS STR-112?

I want to check the lateral result against mine. I have to adjust base HTA by 1.4 degree to shift the curve to "fit "
1784959357045.png


1784965510773.png
 

Attachments

Last edited:
Diffrent cartridge, different table, VTA script check using FISHER MT-6330 with AT 540ml shimmed to tilt 0.5 degree to center of record

DIN VTA 20.4. CBS script 20.3 degrees

1784990207467.png




optically VTA Running 20.5'
1785053596282.png
 
Last edited:
Only azimuth shim?
 
Yes , but tonearm height not adjustable for VTA om Fisher 6330, will check VTA optically one day when by back allows. but i think the counterweigt arm end is maybe low, due to side shim
 
Balle Clorin said:
PS could you please share a recording of the whole Side B of CBS STR-112?

I want to check the lateral result against mine. I have to adjust base HTA by 1.4 degree to shift the curve to "fit "
Click to expand...
The file is in the dropbox linked in PM. You can publish the result in this thread.
 
@Balle Clorin , did you check HTA with my file? I’m not sure but think I need the Python script to run it myself. Have only used the online VTA app.
 
Thomas_A said:
@Balle Clorin , did you check HTA with my file? I’m not sure but think I need the Python script to run it myself. Have only used the online VTA app.
Click to expand...
is this what you wanted?. I atteched lastest scripts single=web version and multiple tracks( calls single version)
1785667162501.png


here is the script -single track- core file, and multitrack=full side B

Do not know why HTA can deviate som much

1785667440777.png
 

Attachments

Lateral and vertical?
 
Claude blame the cartridges inaccuracy. will not admit script faults
 
Summing channels would be lateral signal only. Inverting one channel and summng would be vertical signal only.
 
Balle Clorin said:
Claude blame the cartridges inaccuracy. will not admit script faults
Click to expand...
Should they be summed to mono instead? I have not given it a thought but HTA should not differ between channels.
 
You must log in or register to reply here.
Back
Top Bottom