May look a little different now, but' it's the same loop at heart. I do get asked about this pretty often though, so a little history lesson for those interested:psychodave wrote:So what are the differences between loops "rev 1B" and the current offering of "rev3A". I see a lot of changes.
The rev1B boards were the first version of the ZL loop that I released with Metro. We wanted things as dead simple as possible back then, no confusing options, extra parts, or controls. So I designed those first rev1B boards to be for pedal level loops only.
After a while, enough guys expressed interest in a line level version of the loop, modding rev1B boards for this purpose was not easy/practical, so rev2B was briefly introduced to try out the idea, see if it would be a worthwhile option. Intent was to just add the most basic provisions on to the board to allow for a line level possibility. Was just the bare minimum changes needed for that compared to Rev1B essentially.
Proved useful to have a line level option available, so I very soon after decided to do a third/final revision, rev3A (current). It came about mainly to just incorporate the line/pedal option permanently on the board in a way that makes assembling the loop as one or the other extremely easy to do. In the process, thought I'd also just "pretty" some things up a tad, make the trimmer top adjust for easier tweaking during assembly or install, make some other very minor changes (though NOT because they were needed or due to any existing problems in any way, but simply because I could, figured "why not?").
So, a line level option was the main driving force for the few revisions the loop went through. If not for that, rev1B would very likely still be the current version. The "heart" of the circuit has not changed, all 3 versions should perform the same in actual use. I still use early original rev1B loops in my own personal amps by the way. Though it would literally take me just a few minutes to swap them out for current rev3A versions (and I could get the loops for free to boot), it would still be be a waste time. I do not need/use line level effects, so don't need or want a line level version of the loop. After swapping out a rev1B loop for a rev3A pedal level loop, I would not hear any difference at all, hence just no point.
So, that's the story on the revisions. Most products evolve over time, and though the ZL loop has as well to some extent, those with earlier versions need not worry they are "missing out" on anything vs. the current version. Again, I still use the originals myself (and never plan to swap them out). The loops were designed from day one to be tonally transparent and very simple to use. That has not changed, you guys just have the option of ordering the ZL loop as line level (if desired) these days.
Last thing I should mention here is that the Metro store does not show a line level ZL loop option. If a line level loop is desired , you just need to specify that when you place your order. If one needs the usual pedal level version, nothing need be specified when ordering.
Thus ends the Zero Loss loop history lesson...
