Exactly where did I say that the Solwise filter doesn't meet the spec? By their very nature electronic filters vary in performance; you can meet the spec with a fairly simple filter (like the Solwise) but you can get better than that minimum performance with a superior filter (like the ADSLNation). We're not talking about absolutes here but shades of grey: many filters meet the spec, but some are better than others.

Eric

In reply to:

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many filters meet the spec, but some are better than others.

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A filter either meets the spec, in which case it meets it completely or it doesn't. The line on which they are to be used also has a spec. If it doesn't meet the spec the filter probably won't work. Some filters might work in that circumstance, but you now have two unknowns: the inadequacy of the line and the capability of the filter to perform outside it specified requirements. What indication is there that the filter will always work well with the inadequate line? Wouldn't it be better to deal with the problems in the line rather than try unspecified additional features of the filter which may or may not be up to dealing with unknown further inadequacy in the line?

If a filter meets the specification, it has completely met the specification. It is adequate to the task. Do you usually describe things which are correctly designed to fulfill the task for which they are designed as "nasty"? If you normally do use this word to describe the perfectly adequate then I agree that you did not accuse the Solwise filter of being below spec.

Hope the OP is following all this ok

I apologise to the OP for an element of sideline. It is very possible that the original filtered faceplate provided by Solwise was faulty, though there are other possible explanations of the symptoms. The suppliers should be prepared to provide a replacement which should then work. That is not quite the same situation as the suggestion that the filter was inherently inadequate (and the major problem detected here could hardly be explained by the marginal differences that might exist between different filters which meet the required standard to which the line itself is also expected to conform).

For those who have been following this little drama, I fitted an ADSLNation faceplate this morning and all is now well. The phone works fine without needing an intermediary filter.

So in summary, either the ADSLNation faceplate is 'better' in my circumstances than the solwise one or the solwise one I had was simply faulty. I am not really bothered either way, I am just happy that things are now working as they should.

Then we're all happy.

Eric

Except Solway? .....oh..and possibly junderwood

I think I'd rather trust actual experiences over theory anytime. As the front-page editorial on this web site says, ADSL filters which were OK for 1M and 2M broadband may not work well for ADSL Max and ADSL2+. If you visit the ADSL Nation website, they have a page showing the innards of some so-called "in spec" filters, and it's obvious that not all filters are the same.

Well yes, and the notion that an in-spec filter should always work with an in-spec line is naive to say the least. In fact I'm not at all sure that there is a spec for the ADSL quality of a telephone line, is there? If there is, it's certainly not guaranteed; the only guarantee is that the line is suitable for low frequency voice communication.

Eric

True and there are plenty of examples on here and that I have come across myself were two filters in series is required so the specification is obviously not enough sometimes, SKY boxes being particularly notorious. Basically all the spec for a filter states, from an interference POV, is that it should have certain levels of rejection of unwanted frequencies at certain frequencies. I believe it is 29db at 32KHz (upstream) and 55db between 300KHz and 1.1MHz (downstream) which I don't believe has changed since 512Kbps days. I have many old and some newish ones complete with CE mark that test within spec and are fine on fixed speed up to 2Mb but are rubbish on LLU or MAX even on internal wiring that is near perfect. While the basic specification is adequate in the majority of situations there are so many variables between different consumer home setups as regards what is connected as well as the range of telephone line conditions that it would be surprising if there weren't situations where a filter meeting the basic specification was inadequate out of the millions online.