What innovative, unconventional cartridge designs can you recommend?

In addition to their DS Audio pres and a few mainstream components such as amplifiers, Mr. Nixie’s website mainly features a plethora of bizarre devices.

As far as I can tell, their DS-Audio to RIAA Converter, "barely larger than an XXL cigarette pack!", converts the cartridge’s signal to a format compatible with any preamp’s MM phono input. Presumably that involves subtracting RIAA equalization before the preamp adds it again.

As y’all know, DS Audio open-sources their equalizer design in an effort to facilitate acceptance of the technology:

https://ds-audio-w.biz/cms/wp-content/uploads/2021/11/Technical-information20221212_c.pdf

I don’t know about you, but I’d rather take a stab at building a DS equalizer myself than give Mr. Nixie 799€ for what appears to be $60 worth of parts.

The description highlighted, relating to a content on the Mr Nixie Web Site are a concoction not typically seen in use.

The guestimate of approx' 10%-15% BOM for Parts relating to retail is quite typical, hence why DIY Builds have such a large volume of Builders and Wannabe Builders.

I'm totally pro avoiding retail costs and achieve the most attractive of designs and function at the side of the scale for costs, that are considerably less than retail.

My route using commission design/builds does add to the cost quoted above, but still enables substantial cost savings to be had, which is first of the experiencing 'music to my ears'.  

@tcutter 

If there are settings for the bass output, I suggest you start at the highest frequency setting because the bass can be prodigious

The SoulMate equaliser arrived yesterday, so I got a chance to read the manual.  There is a single bass filter setting (on or off) which seems to be there to eliminate very low frequencies from warped records (warp speed?) but is does not apply to the optical cartridge input.  This is the entry-level equaliser from SoulNote after all ...

@devinplombier 

"barely larger than an XXL cigarette pack!", converts the cartridge’s signal to a format compatible with any preamp’s MM phono input

That was another red flag for me on Mr Nixie’s product set.  I think he equalises the optical signal, converting it from position-dependent to velocity-dependent, while leaving the RIAA conversion untouched.  Using a pre-amplifier’s MM input deals with RIAA.

But it also negates one of DS Audio’s unique selling propositions - the voltage output from the cartridge is about 14 times higher than a typical MM.  Mr Nixie reduces the output voltage (not good for the signal-to-noise ratio) only for the pre-amplifier to boost it up again.  No thank you, Mr Nixie.

I am unclear whether Knoff Hoff is a German attempt at humour - a knock off maybe?  Any way, I knoff hoffed it from my list!

This thread meanders among topics related to optical cartridges and equalization, and it's pretty interesting (to me, at least) 

https://www.diyaudio.com/community/threads/diy-optical-cartridge-preamp.371231/