What would you do?

BillESC

Well-Known Member
The back story. I had bid on this country club installation but didn't get the job.

Skip forward one year.

The original contractor is under indictment for fraud (another client) and has skipped town.

I get a call from the club, some of their speakers aren't working. In the main dining room only 4 of the 12 ceiling speakers are working, in the second dining room none of the 4 speakers are working.

I start by taking down the first non-working speaker (Niles CM610) closest to the source and to my surprise, discover it only has two wires attached to it (not part of a 70v system.) It turns out, every ceiling speaker has a home run cable back to the source system. I test the speaker and it is fine. Further investigation yields the following discovery.

The system is comprised of the Denon AVR 689 tuner/amplifier which supplies 80w per channel. The main dining room is on channel A and the smaller dining room is on channel B. Each channel's output is fed into a Niles SS-6 speaker selector. It appears most of the SS-6's channels have become inoperative.

My question is: What approach would you take to make the system operative.
 
Are they wanting to just make it operative or to not want to have to keep calling you out when things fail?

Let me see if I understand the system configuration correctly. The Denon AVR-689 has two main stereo outputs, A and B. The left and right signals of the A output are run to a Niles SS-6 which connects to six pairs (left and right) of speakers in the Main Dining Room. The left and right signals of the B output are run to a Niles SS-6 which connects to two pairs (left and right) of speakers in the Small Dining Room. If that is correct then maybe we should start with the simplest thing which is making sure the speakers are all switched on at the Niles SS-6, although I assume you already verified that.

Next, Page 12 of the SS-6 manual addresses the "Protection" button on the front panel of the SS-6 and notes that it should be on when connecting 3 or more pairs of 8 Ohm speakers. Apparently the "Protection" button engages the impedance compensation and based on the SS-6 manual should be engaged for the Main Dining Room. So another button setting to verify.

Moving on, the Niles SS-6 impedance matching capability seems to be based on the amplifier supporting a 4 Ohm load. Page 4 of the Niles SS-6 manual states "The actual impedance load the SS-4/SS-6 presents to your receiver or amplifier will vary, depending on how many speaker pairs are playing and the impedance rating of each speaker. If you have four pairs of 8-ohm speakers playing, the SS-4/SS-6 will present a 4.5 ohm impedance load to your receiver/amplifier." In the Main Dining Room with six pairs of speakers connected in parallel the impedance is probably even lower and closer to 4 Ohms. However the Denon AVR-689 is only rated for full response at 8 Ohms and a minimum load of 6 Ohms. So that could be a problem.

It should probably also be noted that the warranties on the Niles speakers and switcher specifically exclude commercial use, so a misapplication to start with. In general, it seems to be a system using numerous residential components combined with an amplifier that doesn't seem appropriate.

This brings us back to the initial question, do they want it operable or reliable? The answer to that question may lead to two quite different directions.
 
The original contractor has the big dining room on the A channel of the Denon and the small dinning room on the B channel.

The 12 speakers of the big dinning room are doubled into the 6 channels of the SS-6. The small dining rooms 4 speakers are doubled into channels 1 & 2 of a second SS-6.

This is a high end country club and will want reliability. Of course, they are concerned with cost which is why they went with the low bidder in the first place.
 
The 12 speakers of the big dinning room are doubled into the 6 channels of the SS-6.
The SS-6 has stereo outputs. By "doubled" do you mean that one speaker is connected to terminals 1&2, and the other is connected to terminals 3&4 (which would be correct), or that both speakers are connected to the same set terminals?

-Fred
 
The original contractor has the big dining room on the A channel of the Denon and the small dinning room on the B channel.
Probably just semantics but the Denon AVR-69 main (front) channels are left and right for which two sets, A and B, of connections are provided. What I am envisioning is the left and right channels of Front output A going to the Main Dining Room SS-6 inputs which are on the same terminal block, one channel to terminal 1 and 2 and the other to terminals 3 and 4. Similar for the Small Dining Room but with the connections at the AVR-689 to the Front output B terminals.

To continue the connectivity, then as Fred noted, on the Small Dining Room Niles SS-6 they apparently have one speaker to terminals 1 and 2 on the Speaker 1 output, one speaker to terminals 3 and 4 on the Speaker 1 output, one speaker to terminals 1 and 2 on the Speaker 2 output and one speaker to terminals 3 and 4 on the Speaker 2 output. The Main Dining Room is similar but with 12 speakers connected to the six speaker outputs, one to terminals 1 and 2 and one to terminals 3 and 4 on each speaker output of the Niles SS-6.

That connectivity seems to make the most sense however I think there are still some critical problems with it. For one, I believe the A and B output connections on the Denon are simply parallel connections off the same internal left and right amplifier channels rather than being separate amplifier outputs. According to the AVR-689 manual and rear panel, when using both the A and B outputs the loads on each set of connections should be between 12 and 16 Ohms, thus if they are in parallel would result in a 6 to 8 Ohm total load, which matches the amplifier's ratings. However, it sounds like the load being applied to each output is more like 3 to 4 Ohms with a resulting 1.5 to 2 Ohm total load. That the amp has lasted this long while apparently driving a load so far below it's rated minimum load speaks pretty well of it.

Maybe I'm misunderstanding something about the installation but otherwise I think the Owner really needs to consider starting over with a properly designed and installed commercial system. I'm not sure how they could make the existing system reliable without major modifications and even then you'd have a system with virtually nothing under warranty.

I also see some potential operational issues with the current setup that might be resolved or improved. For example, they seem to have no independent volume control for the two separate Dining Areas, the overall level is common for both with the relative level in each space then apparently determined solely by the relative impedance that each SS-6 presents to the Denon. That might be something they would like to change.
 
Add one of these to each speaker: ATLAS LT-70

Add one of these to each of the tuner/amp A & B output: ATLAS AF140

Explain to the folks:oops: they may want to use you the first time in the future:)

I know this is a make do and my suggestion is based on the thought that the tuner / amp and whatever is connected to it is working for them. I know limitations on the levels available for each room are somewhat low.... well, if you think about it BGM in a dinning room....maybe it really won't be that low.

Is this what I would do from the get go? NO. Is this the optimum fix? NO. Does it make the best use of what they already have in place? From what I can tell, yes.

Do they have the money to rip all out and start over?

Yes= well, that's a no brainer.
No=compromise

Just my .0000002 worth (inflation)

Oh, and remove the SS-6
 
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Many amplifiers aren't happy if you just hang a 70V transformer off the back of them.

Personally I would look into just replacing the Denon entirely, or at least using it just as a preamp/ tuner. I am assuming that the power requirements on this job aren't high, so you might want to investigate 8ch amplifiers. Ashly Audio has a great product with the ne8250 which is also (IMO) very affordable for a 8ch amp. Parallel up the speakers in pairs per output channel. Crown has the CTs8200 which is about double the cost, but includes switchable 70V outputs. I haven't had the greatest experience with them though, I've had to send several back to the factory for repair within a year of purchase.
 
Personally I would look into just replacing the Denon entirely, or at least using it just as a preamp/ tuner.
I don't see any preamp outputs on the Denon, so you'll probably need to replace it. It's just not the right unit for this job.

Does it need to do more than tuner/CD player (if that much?)

-Fred
 
The AF140 is an AUTOFORMER. I have never seen a case, where properly installed, that the amp "didn't like" the AF140. I am 46 years old and have been at this for a while.

However, to make sure that I didn't enjoy foot for supper tonight, I contacted tech support at Atlas. Atlas and I are in the same boat. He emphasized that this is EXACTLY one of the applications that the AF140 is designed for.

I will attempt to attach a document related to the AF140. If sucess is not mine then it can be found on the Atlas website.

Again, yes, better solutions are to be had. This is only offered as a possible solution.
 

Attachments

  • 140 WATT autoformer.pdf
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Did the club want the speakers in each of the two rooms to be broken into switchable zones?

Or was the SS-6 purely put in by the last installer to balance the speaker loads?
How easy would it be to rewire the system to one run of 70V cabling or would it be easier to use the existing wiring and just parallel it back at the amplifier onto a 70V system?

Brent
 
Honestly, at this point I would not touch it.
Find someone who deals with this kind of thing all the time and sub it out to them.
You're guaranteed to end up looking good and still make some money.
 
You could add transformers to all 16 speakers and two autoformers on the receiver outputs (the left and right channels, not both A and B as those are paralleled outputs for each channel). Then replace the two SS-6 switchers with terminal strips or similar for each channel to let you parallel the speakers together (all the left channel on one strip and all the right channel on the other). That would probably work.

However, this would leave you with speakers that have no warranty and a receiver that apparently has been pretty badly abused due to the original system installation. Do you want to support that or inherit any future problems? It also leaves the Owner with a system that not only cannot independently control the volume of the two dining areas but that also is a two channel ceiling speaker system, something that I have typically found to not work real well in most applications.

So it sounds like you have two potential options to present; a sort of "get 'er done" option that seems to get the existing system up and running but doesn't really fix all the long term issues or an option to essentially start over with more appropriate design and equipment. Whether you want to either or both options is up to you.
 

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