SM Pro Audio: M-Patch 2 volume control

SM Pro Audio are an intriguing company. Half German, half Australian. They sell unusual devices and problem solvers for little money. I discovered them while searching for a pro-quality volume control to replace an unbalanced consumer one. I felt my new ADAM S3-As should be treated right. The M-Patch 2's main audio path is passive and balanced. Two stereo inputs have individual volume controls with a half dB interchannel accuracy down to -60 dB. The main input is via balanced XLR/TRS combo connectors and feeds a larger volume knob. The auxiliary input is via both RCA phono and stereo 3.5 mm minijack (for iPod, etc.). Two switches with LED indicators select one over the other. Two more switches with LEDs control the two balanced outputs. Both outs can be used simultaneously. Further switches for mono summing and mute, as well as a headphone output with its own volume control, complete the picture. I was used to a single pot, so this seemed like overkill. However, I thought of a use for every facility offered, with nothing further to wish for. How come I never noticed SM Pro before? I must now admit to being a total gear snob. I look around for the most expensive product, then wait until I can afford it. I checked the price of the M-Patch 2. 125 Euros. No way-I can't buy something that cheap! I promptly forgot SM Pro and let things slide as I became engrossed in 5.1 mixes for Rave HD. For the time being, I used my DACS HeadLite as a multichannel volume controller. One day while ordering some bits and pieces online, I noticed that one extra purchase would gain me free shipping. Why not? Come to me M-Patch 2. The unit looked just like the website photos-clean edges, excellent panel print, smooth pots. I used to be an electronics hobbyist, so I always have to peek. I was very impressed by the innards. Quite a number of immaculate PCBs interconnected by neat looms with multi-pin connectors. This appears to be much closer to Berlin than to Beijing. A pair of included wings can be used to make an angled tabletop unit or for rack mounting. (These wings are thin enough to fly!) The unit is light, so I don't think tabletop would work. In the rack, the M-Patch 2 flopped about when switching, so I used Blu Tak to firmly anchor it underneath. An external wall wart is used to power the LEDs and headphone amp. On the ADAMs, a tiny little hum from the previous unbalanced hi-fi controller was entirely gone. Without audio, and with the headphones up full, the pots made tiny scratching noises when turned. This is the nature of passive; no pot can be silent if there are DC leaks. I did find DC offsets of 3-4 millivolts on my Pro Tools outputs and ADAM inputs. Thankfully, in actual use, no scratching can be heard whatsoever. I have been happily using this unit for the last month, tracking and mixing the 40-year anniversary album by the Lee Valley String Band. Bluegrass thrives here in the Lee Valley Delta. 82 The headphone output is very decent even when A/B'ed against the DACS, which is one of the best. I can now play CDs without having to import into Pro Tools. The B output drives a second-opinion rig. I can now check mono compatibility without having to pan center. It all works perfectly and has slotted right into my setup as if I had designed it. The sound is impeccable, as you would expect from a passive unit. I am still a snob. I feel I am cheating. I have ordered some really expensive Towersonic speaker stands to compensate. For my next 5.1 mix, I may buy a Coleman Audio unit-or maybe not. ($219 MSRP; www.smproaudio.com)