IMF RTS 1 loudspeaker opinions please

[DSJR]

RTL stood for REFLEX Transmission Line, in other words, a longer than usual port that ran full width on the box helping it to be more rigid. The RTL2 was the star of this particular range we found, but the RTL1, with identical drivers (and possibly crossover?), could be a little fierce without the extra bass extension to balance it. Very 'clean' as I remember and great for jazz. Will work fine very close up to a back wall and should reward a good system as well as tolerate a less than exalted one.

Only thing I can say against this series of RTL's is the cabinet vinyl finish, which was tolerable in black, but bubbly in the rosewood colour they also made these in. I thought at first that £50 is a tenner or more too high, as RTL2's used to go for £75 or so, but as used prices are stupid these days, so I could be way off...

[walpurgis]

RTL stood for REFLEX Transmission Line

A bit of a misnomer I suspect. I doubt the 'reflex' bit had much to do with a true Hemholtz resonance design. More likely 1/8 wavelength line like the B&W DM2 or possibly even 1/16 wavelength on the small models, which would most likely be a selling point than a feature that properly augments bass output via the line.

[YNWaN]

The concept of a transmission line is that the back wave is gradually absorbed by the 'line' and is, in effect a pure infinite baffle. The reality is that for low frequencies you need an extremely long transmission line and even when folded up this makes a very large cabinet. The halfway house is to accept that some output will still exist at the end and this can be used to couple to the room so long as the output phase is correct. The reality is disjointed and badly timed bass - PMC included (quantity doesn't equate to quality).