Niles Speaker Selector-To Hot To Touch! Ouch!

[mexwave]

This system is at a customers house,so I dont have model #'s at hand. I installed a new Onkyo stereo only tuner/75 watt amp with a new 50 watt Onkyo power amp to drive 3 zones or 6 speakers all rated at 8 ohm via a Niles preowned 4 zone speaker selector.

Connections are this:
Rca Right & left from tape out of tuner/amp to Rca in on power amp. 16/4 wire to amp in on Niles Spk. selector. 16/4 wire to 3 pair of speakers. One zone not being used.

The Niles unit gets hot enough that you can barely touch it. If I remove a spk. grd. wire at power amp and reconnect it, there is a spark. When I remove the tape line in Rca's from power amp, there is no arc on the ground wire.
If you need more info, please let me know. Any thoughts on this will be very helpful.
Thanks in advance, Mexwave

[RichPA]

It seems to me that if you're confident the hookup is correct, there has to be a bad resistor or short circuit in the impedance-protection circuitry inside the selector. Does it actually work, in the sense of getting sound to all the speakers?

[westend]

Have you tried using only the Onkyo tuner/amp (a receiver?) to send a signal to the Niles speaker selector?

[cademan]

From what I can read, you need to be connecting that speaker selector switch directly to the speaker output terminals from the onkyo amplifier. Speaker selector switches just do not get hot. Something very wrong here.

[cademan]

OK, did some research, is it one of these?

http://i297.photobucket.com/albums/mm214/cademan652/Nilesspselectorss-4.jpg
http://i297.photobucket.com/albums/mm214/cademan652/Nilesspselectorhps-4.jpg

These need to be connected from the speaker out terminals from the amplifier/receiver to the amp in on the selector box. Does this help??

[240sx4u]

You don't have both power amps connected to the single switchbox right?

I ran one of these at a buddies place with a bigass yamaha amp and no heat was given off.

Evan

[whoaru99]

You don't have both power amps connected to the single switchbox right?

I ran one of these at a buddies place with a bigass yamaha amp and no heat was given off.

Evan


Afaik, depends on whether it was just a plain switch box or an impedance-matching switch box.

A plain switcher shouldn't generate any heat. An impedance-impedance matching switcher will, but I'm not exactly sure how much.

[avguytx]

How about calling Niles and talking to Technical Support. That would be your best bet and maybe it's just an issue with that particular unit. We sell the Monster and Mitek units here and have had no issues with them.

Or better yet....do you have another switcher you can swap it out with? Troubleshooting or a phone call is typically faster than waiting for a response from the internet. Just my $.02 from being in the industry 25+ years.

[240sx4u]

Afaik, depends on whether it was just a plain switch box or an impedance-matching switch box.

A plain switcher shouldn't generate any heat. An impedance-impedance matching switcher will, but I'm not exactly sure how much.

It was a niles impedance matching unit. I had a pair of them and a pair of amps. We weren't pushing 200wpc through them or anything but they certainly didn't get hot enough to fry an egg on!

Maybe its a tube based switcher? lol

Evan

[NicoR]

Hmm, it could be that the neutral wires for the speakers are at different potentials due to an amp problem. If the Niles box automatically connects all the speaker neutrals together, then it would have to dissipate that potential from within. Would explain the heat and the spark.

With the amp on but not playing anything, hook up a voltmeter between both L- and R- and then between L+ and R+. There should be little if any voltage.

[redcoates7]

OK, by connecting the Tape Out from the Onkyo receiver to the "Power Amp IN" on the Onkyo Power amplifier, you're running that amp full-tilt boogie into the Niles selector...in other words, any time the Onkyo system is turned on, it is playing at full output directly into the protection resistors of the Niles Selector. That's why you get a spark when the RCAs are connected...RCA connected means signal is input to the amplifier, which means amplifier is producing full rated output into the load presented by the Niles selector.

Your best bet would be to turn off the "Protection" feature of your speaker selector, which takes those big resistors out of the circuit (which cools things down immensely!) Replace any volume controls around the customer's house with Impedance Magnifying models of the appropriate power rating for your Onkyo ampifier and you should be off to the races.

Good luck

[avguytx]

Hmmm.....ok, after reading redcoates response about the hookups, it got me thinking. You're using the "tape monitor" connections to tie in to the separate power amp???????

[mexwave]

With the protection switch off, there is no audio. The switch is being overloaded. With all volume controls up, I'm going to start by turning down the gain control on rear of power amp to an exceptable listening level for the home owner and see if that helps. I will respond back later. Thanks for all

Mexwave

OK, by connecting the Tape Out from the Onkyo receiver to the "Power Amp IN" on the Onkyo Power amplifier, you're running that amp full-tilt boogie into the Niles selector...in other words, any time the Onkyo system is turned on, it is playing at full output directly into the protection resistors of the Niles Selector. That's why you get a spark when the RCAs are connected...RCA connected means signal is input to the amplifier, which means amplifier is producing full rated output into the load presented by the Niles selector.

Your best bet would be to turn off the "Protection" feature of your speaker selector, which takes those big resistors out of the circuit (which cools things down immensely!) Replace any volume controls around the customer's house with Impedance Magnifying models of the appropriate power rating for your Onkyo ampifier and you should be off to the races.

Good luck

[avguytx]

And you've never said....what model Onkyo gear are you attempting this to work with? We use multiple switchers in our demo room for the TX-SR606, TX-8522 and an M-282 and have NO problems with heat, etc. Also, Zone 2 of the 606 is tied into an ATON DLA-6 that also has no problems with heat.

[scootchu]

Connections are this:
Rca Right & left from tape out of tuner/amp to Rca in on power amp. 16/4 wire to amp in on Niles Spk. selector. 16/4 wire to 3 pair of speakers. One zone not being used.

That doesn't make sense. Tape out? RCA in to power amp? This means the signal going to the amp isn't variable... into a power amp you say? Well that sounds suspect for one thing.

[avguytx]

I concur...completely.

[westend]

I have the same Niles four speaker switch and the protection switch, whether it is off or on, lets the signal pass to the speakers. I'm thinking you have a bad selector switch ..and...you have a full strength signal being fed to the amp, as others have noted.
Depending on the amount of resistance from the amp through the selector and through the speaker wiring and the load of the speakers, you might have toasted the selector switch. For a multi-speaker system as you've described, the use of a heavier less resistant wire might be a better choice. 12 guage from the amp to the selector and 14 gauge to the speakers might have been a beter choice. Still, you have the non-variable signal from the receiver to the amp and that isn't a good thing. We still don't know what kind of speakers, length of run, and the impedance of the speakers.
My suggestion would be to run a single pair of speakers from the receiver, checking each run to each pair. This would eliminate the second amp and the selector switch. After you have checked each pair, hook the receiver to the amp using the "Aux" out and "Aux" in jacks, respectively. Try the selector switch with one pair of speakers at a time, noting any heat build-up. If none exists, hook them all up and see if the selector switch functions.

[whoaru99]

The speaker wire gauge is not the cause of the overheating, although a short circuit in one or more of the speaker runs might cause the overheating.

I too agree with the assessment that something is connected improperly, and the amp connected to a "tape out" jack is immediately suspect. The descriptions of the connections and components are not complete enough to really understand what is going on.

Frankly, I'm a bit concerned when I read "customer" and "home owner"...