[mack]

I have 4 speakers. Big, 2 sonys with a 10 inch bass, middle and treble. and also 2 speakers with 12 inchs bass and super powerfull treble. So my ONKYO amp isnt the most powerfull i dont think, in terms of AMPS. maybe 800.

So on the back of the amp there are metal contact plates (with a screw thing to hold the wire down) for the front speakers and metal plates for the "remote" speakers. The thing is i think that the 800 AMPS or whatever is divided between the front and back contact "plates".

Here enlies the problem, the "remote" contact plates dont work, so I twisted the wires together and put them all on the front contact plates. So now when im listening to low volume music the left speakers will fade out and stop working, until you turn op the volume and they violently come back to life. Is it time for a new amp or what? Can I get my current amp repaired, and most of all am I damaging my $$$ speakers in the process?

 

[Wumpus]

(Terms may not be totally correct)

You are running your speakers in parallel. This is bridging your speakers down(8 ohms to 4 ohms -or- 4 ohms to 2 ohms). May or may not be related to your speaker problem. You should really run your speakers in series -- positive from amp to positive on one speaker, negative from that speaker to positive on other speaker and then the negative of that speaker back to the amps negative.

 

[mack]

? Both speakers are on the same contacts. So there are 2 left speakers on the left contact, and the red on the red and the black on the black for both wires.

SO are what you saying is that i should have one left speaker running black on black and red on red and have the other left speaker running black on red and red on black?

 

[Wumpus]

Maybe this will help:

http://www.usspeaker.com/speaker wiring-1.htm

Your amp has a certain impedance(ohms), and your speakers should match it.

If your amp is 4 ohms, and both set of speakers are 8 ohms then your wiring would be correct.

 

[66]

Maybe this will help:

http://www.usspeaker.com/speaker wiring-1.htm

Your amp has a certain impedance(ohms), and your speakers should match it.

If your amp is 4 ohms, and both set of speakers are 8 ohms then your wiring would be correct.

is the only problem that the volume knob drops one channel at a certain point? that sounds like dust in the knob. a local hifi shop should be able to help that out.

what impedence are the speakers (look for the omega symbol). and what impedence will the amp run? since you are talking about the amp puting out AMPS you might be better off giving the model number. volts x amp = watts.

 

[mack]

oh ok.
The amp is an ONKYO tx-905, its stats are...

"60 watts of continuose power per channel into 8 OHMS...(2 x 120 watts of dynamic power at 4 ohms)

The rear speakers came with it, They are genesis. I dont have the manual for them though

The front speakers are Sony's, they are new, its says they are:

8 OMHS
Max input power of: 120 watts
Sensitivity of: 88db (1w, 1m)

 

[S.n.a.k.e.]

Mack,

Assuming each speaker is an 8 ohm load to the amp, hooking two speakers to the contact plate will result in the boxes being put in parallel. This makes the load for each channel of the amplifier 4 ohms (8 ohms / 2 speakers). You stated that you amp will do 120x2 into 4 ohms. Thus you end up with 60 watts per speaker (120 / 2). 60 watts is not a lot of power.

As far as the fading out, perhaps there is (as suggested) a bad spot on the volume pot, which you can spray some contact cleaner into, and then 'exercise' the knob. Maybe you even have a few weak output transistors which 'fade' as the current load becomes greater (louder volume).

The other contact plates (remote) usually are activated with a front panel selector that says (sometimes) A, B, A+B or some such. You can probably run this way for a while, but you really should get a new amp that is capable of driving 4 speakers. Choose a wattage that is approximately 1.5 times the speaker rating capability. EG: If the speaker is rated for 500 watts, get a 750 watt amplifier. And remember that as you add speaker in parallel, you lower the resistance (ohms). Amps make more power at lower impedences, but you spread that greater power over more drivers. And most amps (unless stated) dont really like low impedence loads (< 2 ohms) as that begins to approach a direct short (0 ohms). Just check specs before doing weird stuff.

HTH,

Marc