The Incredible Technics SP-10 Thread

Plots of the FG after the filter and amplifier. No speed instability here.

The last plot is the SS platter at 25Hz span.
 

Attachments

  • FG_OEM.jpg
    FG_OEM.jpg
    191.4 KB · Views: 236
  • FG_SS.jpg
    FG_SS.jpg
    192.2 KB · Views: 233
  • FG_SS_zoom.jpg
    FG_SS_zoom.jpg
    209.9 KB · Views: 236
Oops I actually zipped the incorrect files as I had done a number of measurements attempting to get the signal in audacity stable. I initially used a 10x scope probe but this caused too much attenuation for the Focusrite.

I have only attached the OEM and SS platters as there is little difference between SS and GM/Delrin in mass.
 

Attachments

  • 1.zip
    2.3 MB · Views: 40
  • 2.zip
    2.4 MB · Views: 34
#2 looks really good for a MKII. My only (minor) complaint is that drift is a tad high.

#1 is so poor I have to think the recording of the FG signal is suspect. Not sure why the peak measurement is so low either.
 

Attachments

  • warrjon_fg_B.jpg
    warrjon_fg_B.jpg
    388.9 KB · Views: 150
  • warrjon_fg_A.jpg
    warrjon_fg_A.jpg
    388.9 KB · Views: 150
You're right the Focusrite (FR) was doing something weird. I wasn't watching the scope trace as I recorded the wav's. The trace was stable then threw a wobbly.

Check this measurement what I did was use a 10dB attenuator to place a load across the FR. The FR is no longer loading the scope trace.

What SW package are you using to analyse the trace?
 

Attachments

  • 1.zip
    2.4 MB · Views: 54
A bit too much dancing going on here for my taste.
The discussion since posts #1683, #1700 has been about determining the audible effect of replacing the mk2 OEM platter with SS, gunmetal, Delrin/SS. No claims of any effect on speed stability were made. The suggestion by others that the heavier platters had a negative effect on speed stability, is not true, based on Warrjon's FG captures and JP's analysis.

Anyone with an OEM platter can compare their data with the wavs provided by Warrjon for heavier platters.

I don't see any dancing.
 
Files with generic names, weird discontinuities, and incomplete tests; comparisons should be done on the same unit as there are untold variables that can affect things in ways that can't always be anticipated. This is basic hygiene.
In a peer reviewed journal article, certainly.

This is a DIY Audio thread with a poster sharing results of relatively straightforward tests.

This is our world of fake news and alternative facts.
Such is life.
 
My bench has been full of SP10's being repaired so no room to do FG W&F testing. Sorry just been busy building and repairing SP10 stuff...

Bon was kind enough to capture 3150Hz tone from his new Vinyl Check test LP, which BTW looks pretty good, way better than the Ulimate Analog Test LP W&F track.

Keep in mind that his 10R has a different cartridge to his mk2, which would account for the difference in W&F between the two.

In order of pictures

10R, mk2 OEM, mk2 Stainless/Delrin.
 

Attachments

  • 10R.jpg
    10R.jpg
    650.3 KB · Views: 205
  • OEM.jpg
    OEM.jpg
    683.8 KB · Views: 218
  • Delrin.jpg
    Delrin.jpg
    685.7 KB · Views: 211
This is what I've busy toiling over. Removing the motor from the aluminium chassis and mounting it in a bentonite plinth.

An SP10mk2 Signature with a long list of modifications.

Resin bentonite plinth.
Remote motor mounting.
Motor redrilled for 3 mounting bolts.
Modified motor rotor to increase rigidity.
Bearing brace.
Gunmetal / Delrin platter.

EPA100
New brass CW stub.
Threaded Stainless CW with locking ring.
Variable viscous damping.

Upgrades to come
New GM / Delrin platter with thicker Delrin
Further motor damping modifications.
Servo LTA
 

Attachments

  • IMG_20210216_121924467.jpg
    IMG_20210216_121924467.jpg
    844.6 KB · Views: 199
  • IMG_20210216_122920210.jpg
    IMG_20210216_122920210.jpg
    740.3 KB · Views: 203
  • IMG_20210216_124317087.jpg
    IMG_20210216_124317087.jpg
    615.4 KB · Views: 115
Last edited: