Axiom Home Page Forums General Discussion Technical Questions Speaker hiss coming from QS8 tweaters

Hi, I'm having a bit of a problem with lots of hiss coming from the tweaters on my QS8s. There is also some hiss coming from the M60s, but it's not really audible unless the volume is very high or if I put my ear to the speaker. Here's my setup:

Pioneer VSX-1015TXK receiver
Axiom QS8 surrounds
Axiom M60 towers
14 gauge speaker wire at about 20 feet long
dayton banana plugs (probably dayton, not entirely sure)
source: xbox 360 with toslink cable/Sony SACD player with rca cables

I've routed all the wires away from electrical cords as best as possible. The receiver sits on the SACD player, and those are the only components in the area.

Any thoughts? I'm a bit of a home theater n00b, so I may have just overlooked something simple.

how loud is the hiss, and how far away are you from the speaker when you can start to hear it? It can be normal to hear a little hiss from the speakers.

Also, how high are the surround channels boosted on the Pioneer?

Hi DS,

All solid-state (and tube) amplifiers produce residual noise or hiss--it's called "thermal noise", a product of the amplification process. In a well-designed amplifier, it should only be noticeable if you are very close to the speaker or tweeter and the volume is turned up fairly high.

It shouldn't be audible from a normal listening position. Thermal noise will vary somewhat from one product to another and how many stages of gain (amplification) are in the chain.

For example, if your receiver has a "Phono" input for a turntable, that will add an extra stage of gain, and some phono pre-amps can be quite noisy. Other well-designed may be almost silent. A moving-coil cartridge preamp adds yet another gain stage, and those too may be even noisier.

Do check your surround levels. If you have them extremely high and/or Pioneer has saved some money in the surround-channel amps, then some hiss is likely audible.

Regards,

Alan

Thanks for all the replies.

kcarlile reminded me that I had forgotten to adjust the distance setting for the amp in my new space. That helped a bunch.

Also, I decided to do a test based on alan's post. I unplugged the fronts and the surrounds and plugged the surrounds into the front outputs. That also reduced more of the hiss, leading me to believe that the receiver has some limitations in the back channels. When I got home, I checked the model number and found it was the older vsx-1015tx, not the vsx-1015txk.

The speakers are only about 6 feet to my right and left, so not very far at all. It's a pretty small room.

Anyway, the hiss is mostly gone unless I jack the volume way up (which I do, sometimes), so I'll probably just deal with it for now. Although I would happily take any more suggestions, if there is anything else worth trying.

Thanks!

Check for snakes, leaky tires, and angry cats.

I can't believe no one suggested a power conditioner

Almost lost my coffee. Good stuff!