Modwright Instruments PH-150 phono stage

ModWright Instruments PH 150
Modwright Instruments PH-150 phono stage

Modwright’s founder, Dan Wright, started out modifying third party components, which makes the company’s name entirely appropriate. But while Modwright still modifies products, today it is better known for its own range of electronics that incorporate both valves and transistors housed in thick aluminium casework with blue lighting, such as the PH 150 tested here. The PH 150 is the only phono stage in the Modwright line, and it’s quite an ambitious beast, with a whole host of controls on the front panel. When you think that most phono stages are totally devoid of accessible controls, this makes a distinct change; it adds to the phono stage’s cost and signal path length, but it has the advantage of making positive changes to cartridge load and gain.

Having used phono stages with fiddly DIP switches, which can only be set by someone who has better than 20:20 vision and a friend to cross-reference the phono cartridge’s loading with the manual, this sort of user friendliness is very welcome. The PH 150’s feature set starts with moving coil or moving magnet cartridge inputs, and a mute position between the two on the left most knob. In true valve engineering tradition, the MC input has step-up transformers to bring the output up to a level where it can be amplified by a thermionic device without noise becoming an issue.

Next in line after the power button is a gain adjuster with three settings; 0dB, -6dB, and -12dB. These apply to both the MM and MC inputs. I used the 0dB setting that produced higher gain than most phono stages, at least with the two MC cartridges I tried. The next knob lets you dial in capacitance to suit specific moving magnet cartridges. Initially it seems a bit odd to include a MM input at all; after all who would use what many consider to be relatively crude technology with such a high-ticket phono stage. However, some cartridges require unusual impedances to show off their best, and it would be impossible to accommodate them all with onboard transformers.

The last controller on this extremely well-finished box is for selecting MC load impedance. This is useful if you are using the internal step-ups. Cartridges usually specify an optimum load, but in practice the best impedance tends to vary with the phono stage in use. So it’s really great to be able to try different settings on the fly. The most obvious difference that the ability to select a MC load impedance on the PH 150 delivers was to change the output due to increased impedance. But when that had been taken into account, I found that not only did it produce surprising differences in timing, but also altered the way that different instruments worked together;  and it wasn’t too difficult to find an optimum setting either. It’s inconvenient that being able to select a MC load impedance involves more than just picking the loudest option. I should also mention that the Modwright has a mono switch which is a luxury even at this price, and an increasingly useful one, what with the slew of reissues being made available in this surprisingly effective format.

blog comments powered by Disqus

Featured Articles