As I've been rolling out a new 3CX system, we are able to use Yealink phones exclusively - except when interfacing with our existing Bogen PA amplifiers. For these we are using the Snom PA1 with the RDL STP-1. The PA1 is not an ideal solution as it has a built-in amplifier and does not offer the outputs necessary to interface with existing PA systems.
I would love to see Yealink offer a very basic 'phone' designed for interfacing with PA systems through existing amps. A 600 ohm output would be ideal, but offering a variety of other connection options that could service all sorts of configurations would only increase the unit's use-case.
For an otherwise complete portfolio, this is one gap that may not be too difficult to fill. I'll take 18 of them.
The PA-1 has a line output, why wouldn't you just use that instead of the STP-1?
Yealink used to make a T18 which was a screenless basic bottom of the barrel phone, but I can see why they dropped it given the demand must have been almost non-existent once the costs of components for the nicer looking phones began to drop. The T19 is still extremely cost effective though.
Really all you need would be a mod cord with a transformer wired up to let you feed it into the amplifier. Something like:
http://www.tamuracorp.com/clientuploads/...MET-35.pdf
Would probably do. (In reality you could probably just turn the volume down on the phone and hook it up directly as the phone output is not going to be huge anyway, but transformer would be the safest route).
Program the phone for auto answer, give it a SIP account or configure it for multicast paging and you're done.
(If you are legitimately interested in a bunch of these shoot me a PM, I have a distributor sitting on some of those T18s and wouldn't mind doing the transformer mod and testing for you)
We tested using the line out (despite Snom saying it's for testing only), but it did not work well on most of our amps on the tel/page input.
Whether using the STP-1 or a transformer, the issue remains that there's not a great solution for connecting 'natively' to a PA amp.
What model Bogen amps are you using?
If you want a native "out of the box" solution Cyberdata makes a 4 port SIP to analog paging gateway, Bogen has their own line of VoIP interfaces, and there are a few others out there (Algo 8301 comes to mind). The problem is they are all quite expensive and typically overkill.. but I suspect since you typically only need one or two per install, they have priced themselves based on low quantity/volume sell rates.
Yealink has demonstrated in the past that they have no desire to do anything analog (hence they don't offer ATAs, FXO gateways, etc) so I doubt they would enter this territory with something like a basic low margin paging interface unfortunately.
So really the options are:
1) Go with a "native" solution like the ones listed, price range about $300-400 US typically per gateway.
2) Use something like the PA1 with your STP1 attenuator ($100-$150 US I'm guessing?)
3) Get a low end Yealink phone and use the handset with the 600Ohm transformer ($40-$70 US?)
The transformer I mentioned is only about 1cm square and it would be trivial to install it and a terminal block or RCA jack, but again I doubt Yealink would do it themselves.
I use the Cyberdata SIP Speakers along with some slave speakers where they are in the same zone... easy to setup.
The Snom comes in handy when converting an office/warehouse from Analog to SIP... keep your existing equipment. I have had no issues to speak of with this device either.