I have developed a method to measure the frequency response of B&O cartridges.

I have used this method to find the technical part of improvements by retipping the B&O SP12 cartridge.

I can prove a major improvement of performance as a result of the fine work - done by Axel Schürholz - info@schallplattennadeln.de

The test.

I used the same pickup unit and tested using 2 needle parts. The first needle parts was a original B&O where I have checked the diamond by microscope - all ok. I performed the frequency response test.

Next I changed the needle part to a re-tipped elliptical diamond - done by Axel, and the frequency response test once more. Exactly the same conditions.

The result:

From 500Hz and up the frequency response was clearly improved and with the higest result at the top end (high frequency range) where the improvement is more than 5 dB (this is a very big improvement)

The tonal balance is much improved and in the following listening test the difference was very clear.

See the frequency response here.

/Frede

Most impressive! Maybe Soundproof and I need to send you our stylus collection to measure the differences!

Peter,

I will be happy to measure your collection of stylus collection.

However, we have to remember this test will be a test of the total pickup. Because for the SP units I can change the stylus only, this is not possible for the MMC cartriges.

A true test would be a MMC before shipping to >Alex and a test after Alex has performed his 'magic.

But - Peter and Soundproof - if you would like your cartriges testes, please send them and I will do it for you.

/Frede

I am sending a collection back to Soundproof soon - his and some of mine and I will suggest he passes them to you next! Just waiting for a different pressing of Time Out to arrive!!