ADSL Filter

I am having to design a hybrid multi vendor MDU for a job. I need to know if an ADSL filter will fry or negatively impact a non dsl voice line being back fed through it to a distribution board. Pretty small thing but could cause a problem.

Thank you folks.

From an engineering and design standpoint, every MDU is different but the ADSL/Voice filter should be transparent to voice, regardless is DSL signal is present or not.

If the modem is of at the CPE, it's basically a voice line, filter or no filter. If there is no filter/splitter at the CPE AND the modem is on. then it's noisy POTS line until the modem is turned off.
I wish I knew that before I got DSL.

I definitely prefer the splitter at the NID. Exceeding the max number of filters will probably do something nasty.

I seem to think that the DSL side essentially sees everything like a naked line and the telco CPE side, filters out the DSL stuff. Why? Both generally acct OK with telephones connected to their ports with the modem off.

The DSL modem doesn't care about polarity. The phone MIGHT.