why do Ortofon SPU C from the 50ies sound so good?

Martinhall & Ldvalve,
I am using the old Mono carts with an Ortofon RMA 309 running on an EMT R80. Maybe it is a well matching combination and the carts are also in a pretty nice condition. Nevertheless I was wondering because most people regard that old vintage stuff not as HiFi or even High End which is not true - You are right.

Best & Fun Only - Thuchan

Dear Thuchan: +++++ " Nevertheless I was wondering because most people regard that old vintage stuff not as HiFi or even High End which is not true - " +++++

that's why exist that long MM/MI thread that confirm your statement with cartridges in the 40+ years old range ( not 60 as your cartridge. )

Now, I own old Ortofon LOMC cartridges and today IMHO are competitive, I own the MC2000, MC30 and MC20MK2 and all them are better that any one could imagine.

Not only Ortofon but other vintage ( by 1980. ) cartridges are really god like Goldbug Ms. Brier or Pioneer PC-70MC or Satin M21P or Victor MCL1000.

So it is no surprise your Ortofon mono sample. As Martinhall point out several vintage cartridges sound good in those old times and with our today systems it still sounds good.
This fact IMHO is a testimony of its great design, build quality and very good execution design.

Regards and enjoy the music,
Raul.

Dear Raul,

I now have a machine with the EMT JPA66 which is the ultimate phono stage / preamp for MM carts too. You are able to adjust MMs precisely and influence the sound in many ways. I do think this could give me another direction, who knows...

best & fun only - Thuchan

Dear Thuchan: I never hear/heard that great EMT so I don't have an opinion if like you say is the " ultimate phonostage/preamp ", what I can say is that is the most versatile phono stage equalizer out there.

IMHO as is important and as makes a difference that very old recordings be played through a matched inverse eq. curve as important is that any cartridge ( LOMC or MM/MI ) be matched with its precise electrical needs: this makes " the difference ".

Anyway, good to hear that you are enjoying music better than ever at your place.

Regards and enjoy the music,
Raul.

If you are thoroughly enjoying the music, then your imagination will be in overdrive and so, the music will inspire you. It will not matter in the slightest if the recording is mono or stereo, played on a Mitchel Galaxy or a BSR Monarch autochanger, that you can hear ALL of the music will be essence of your enjoyment. In partnership to this, is the enjoyment of owning of the finest Hifi equipment you ever wanted. What really is great, is we all have a multitude of different tastes that keeps us discussing the virtues of different music played on a million different setups and contraptions. This has been going on for over a century and long may it continue!
The main reason you old Ortofon sounds so good? Is because you are enjoying the listening to it. Which, is good.