Cartridge or Pre Amp

Based on the specs shown in this listing it looks like the AT-ML150/OCC has the same 100 to 200 pf load capacitance recommendation as the AT150MLX.

Regards,
-- Al

Although like Bill (Bpoletti) I am a very happy owner of a Herron VTPH-2, it would not be a suitable match for the relatively low 22K input impedance of the preamp that was linked to in the OP.

The same concern would also apply to many other tube-based phono stages, although certainly not all. The Manley Chinook, for example, which I believe sells for ~$2.4K, is a tube-based phono stage that would have no problem driving 22K. Also, it is compatible with both high output and low output cartridges and provides a wide range of choices for resistive and capacitive loading.

Regards,
-- Al

The current Tube Box DS has the ECC 83 tubes just like some of the higher priced tubed stages carry. I'm all for upgrading but I'm also aware of the diminishing returns on said upgrades. I'll triple check the DIP switches.
http://www.project-audio.com/main.php?prod=tubeboxds&lang=en

@almarg Agreed.  The Herron would be better matched to a preamp with a higher input impedance.  Keith Herron would be a good source to determine whether changing tubes in a VTPH-2a would overcome a lower input impedance pre.  

My initial post has the incorrect link. This is the correct one: Pro-Ject Tube Box DS