70V system puzzle

[hbiss]

I submit that what you may be seeing is actually a balanced line with transformers on the amplifer inputs. Balanced line level can go for miles (think telephone). If they actually did tap the 70 volt distribution to feed other amplifiers that's not a good way to do it by today's standards. Again, it's probably a vintage system that may have been "modified the easiest way" over the years or that was the thinking back then. In those days music in stores was a secondary concern (really was elevator music) as long as the paging could be understood.

-Hal

 

[egnlsn]

I submit that what you may be seeing is actually a balanced line with transformers on the amplifer inputs. Balanced line level can go for miles (think telephone). If they actually did tap the 70 volt distribution to feed other amplifiers that's not a good way to do it by today's standards. Again, it's probably a vintage system that may have been "modified the easiest way" over the years or that was the thinking back then. In those days music in stores was a secondary concern (really was elevator music) as long as the paging could be understood.

-Hal

Modern systems being put in today all over the country. The transformer which I reference is here. Nordstrom puts way too much money into their A/V systems to consider them a secondary concern.

 

[hbiss]

The transformer which I reference is here. Nordstrom puts way too much money into their A/V systems to consider them a secondary concern.

I'll take your word for it but it's not something I would want to do.

Also I can only go by the Nordstrom I have here. I have never noticed anything other than separate speakers for paging and music. Each department has their own AV setup that is not connected to anything else. They bring in DJs frequently. As far as music, they have a baby grand and somebody who looks like Little Richard to play it. The piano is mic'd and carried by the music system, otherwise it's probably Muzak. Live jazz is handled the same way.

Maybe the Nordstrom you are talking about is in a less afluent area?

-Hal

 

[egnlsn]

The transformer which I reference is here. Nordstrom puts way too much money into their A/V systems to consider them a secondary concern.

I'll take your word for it but it's not something I would want to do.

Also I can only go by the Nordstrom I have here. I have never noticed anything other than separate speakers for paging and music. Each department has their own AV setup that is not connected to anything else. They bring in DJs frequently. As far as music, they have a baby grand and somebody who looks like Little Richard to play it. The piano is mic'd and carried by the music system, otherwise it's probably Muzak. Live jazz is handled the same way.

Maybe the Nordstrom you are talking about is in a less afluent area?

-Hal

I don't think it is the locality as much as the age of the store. Sounds like an older store (not necessarily old, but several years, anyway). We built one ~7 years ago that has equipment very similar to the ones being built today (I'm doing another, which is a replacement for one that is several years old at the same mall. The aforementioned one has a piano, but they have since been done away with. The company I sub for does ~90% of the stores country-wide (I only do the ones locally). Other than the the piano mics (which are being done away with), the music source for the store is DMX, who is in the process of being replaced by another vendor. They are honestly the sweetest sounding background music and paging systems have heard or seen anywhere.

 

[iwire]

Like many things in this trade there are many ways to get the same job done and many of them are right. Why we choose certain methods has as much to do with personal experience with those methods and we tend to down play other possible ways. :smile:

I have done some nice audio systems in large retail stores as well. We had two Bose commercial systems in different departments that needed signals from the main PA. In our case we simply brought a line level source to each one, simple and it works fine. Now I have learned I could use that Lowel device and just grab up local output circuit. Either way will work. :smile:

 

[hbiss]

DMX is in the process of merging (or already has) with Muzak.

-Hal

 

[hbiss]

The company I sub for does ~90% of the stores country-wide (I only do the ones locally)

Do you sub for a company that subs for DMX and do you only handle the sound?

-Hal

 

[egnlsn]

The company I sub for does ~90% of the stores country-wide (I only do the ones locally)

Do you sub for a company that subs for DMX and do you only handle the sound?

-Hal

Nordstrom. All of the A/V systems in the stores (the 90% they do) is what they do: background music and paging, video, intercom, DirecTV, etc. Nordstrom now has a contract with PlayNetworks (rather than DMX) as the music provider.

 

[hbiss]

PlayNetworks is XM and now Sirius too. I knew it sounded familiar, they are the ones I sign my commercial customers up with for their subscriptions to XM/Sirius. I just wish that they would have a business package that is truly free of commercials and DJ chatter. Then they can compete with DMX/Muzak.

-Hal

 

[mdshunk]

That Lowell gadget is neat, but does anyone make a universal input/universal output impedance matching transformer?

 

[egnlsn]

PlayNetworks is XM and now Sirius too. I knew it sounded familiar, they are the ones I sign my commercial customers up with for their subscriptions to XM/Sirius. I just wish that they would have a business package that is truly free of commercials and DJ chatter. Then they can compete with DMX/Muzak.

-Hal

Does PlayNetworks have a satellite feed? What we use is a 4-output player (each output is independent of one another)(one output for the store, another for M.O.H., another for the cafe, and the other for the ebar) and the playlists are updated via the internet. I haven't heard a DJ yet.

 

[hbiss]

Sounds like the same player DMX uses, the Profusion XS. There is a CD but it loads it to a HD and it updates via the internet? These provide custom programs designed just for the customer so no commercials unless they are theirs.

PlayNetworks satellite service is regular XM with some channels blocked because of content, etc. that would not be suitable in a business environment. So the DJ chatter is still there though and it's the lowest priced service.

I do remember that they are providing 15 channels via Direct TV. I believe you use a sat TV receiver and 18" dish and they authorize only those channels. On that service there are no DJs or commercials at all.

I'm used to DMX satellite and a 1 meter dish or Muzak which is on one of Direct's DBS satellites so it only requires an 18".

-Hal

 

[grich]

Back in college I helped maintain paging/intercom systems on campus. Lots of Rauland 100W tube amps. In the student union the background music system was designed to bypass the room volume controls with a relay so paging would always be at full volume. We also used DPDT switches in several locations to switch speakers between different 70V systems.

At church I'm temporarily using a 70V speaker transformer and a pad to steal sound from the main system to feed another amp for an overflow seating area in the social hall.

As iwire said, there are several ways to do some of these things right...depends on the situation.