TBH, I don't know. I've never been good at reading log graphs.

I *suspect* that the different masks make it better for those cabinets that are further away, as I think those lines can make more use of the frequencies that are no longer usable by exchange-based ADSL. But it is no more than a gut feel, and I could easily be wrong.

I found a really good thread here with people posting stats and some with openreach screenshots that show line length, it would appear every 2db or so of attenuation on D1 equates to around 100m line length, which would suggest my copper length is not 200m but more like 500m as my D1 attenuation is 9.6db.

this guy has attenuation slightly higher than me and the openreach device shows 0.5km.

http://forums.overclockers.co.uk/showpost.php?p=2137...

his attainable is much higher but more reading also shows people with much lower attenuation at similiar distance also, there is huge variations which I am guessing is down to crosstalk in localities excluding the people with ali d-sides.

I wonder where the line routing goes with it been over double the direct distance. The cabinet is on the same road as me so maybe it goes up the couple of side streets first that are en route.

I've estimated my distance as 450 meters, never got any engineers to measure it though. I was getting about 50 meg when first connected but then interleaving kicked in and I dropped to 40, which has slowly increased to 45 with an attainable of about 51, I was the first on the cabinet and don't seem to be affected by cross talk, unless the intial drop was due to it. Either way my speeds have always been less than the average for my distance, which is about 60, my estimate is 57. And my neighbour tells me he gets about 55 on speed tests, but I've never managed to get his line stats.

In reply to a post by Chrysalis:

I found a really good thread here with people posting stats and some with openreach screenshots that show line length, it would appear every 2db or so of attenuation on D1 equates to around 100m line length, which would suggest my copper length is not 200m but more like 500m as my D1 attenuation is 9.6db.

That'll be interesting, but I'll have to look later. I think the numbers are off though...

To compare, my current line has D1 attenuation of 11.4 dB, but is only 400 metres. That's my measurements, rather than anything produced by an engineer. Unknown age or condition.

My previous line had D1 attenuation of 14.1dB, and was 550m (measured by me), and was reported to be 550-600m (as reported by the installer's test equipment). The D-side of that line was definitely only 16 years old.

Perhaps you're closer to 300m, rather than 500m.

spanner thrown in the works.

one thing is I am fairly sure its much longer than 200m, or its ali or something affecting attenuation.

So my current sync is probably normal after crosstalk is in affect.

andruec has posted a graph with what you described, his early blocks have less power reduction in fact the first blocks seem to have none, so I counted the missing spaces on his bit graph which I think were lost due to the power masking and then counted mine and in my opinion I lose more so it seems if closer to the exchange there is less of a penalty for adsl crosstalk protection.