newbie thrilled with a23/bp7004 combo but...

[kschaan]

Hello,
First off I want to thank everyone for all the great posts and info I have gathered thru this forum. I have been using my 6 yr old yamaha receiver to drive my fairly new def tech 7004 speakers and have been researching my first amp for quite a while now (by the way, these speakers are awesome!). I finally broke down and purchased a new a23 and am really amazed at how much better it sounds than the amp built into my receiver. I don't consider myself anywhere near an audiophile, however the improvement was very noticable and puts a big grin on my face . I am still using the yamaha as a preamp for the time being, but after listening to the a23 I think the yamaha's days are numbered :lol: .

However, while watching a movie today I noticed during a quiet passage that I could hear quite a bit of noise/hiss coming from my 7004's. I paused the movie and much to my horror discovered the noise got even worse as I increased the volume on my receiver. It's not a buzz or hum sound so I don't think I have any ground loop issues. After playing around with settings I found out that I had the gain knobs on the back of the amp all the way up to thx reference level (which is what parasound recommends). Reducing the gain settings by 1/8th of a turn got rid of most of the hiss. Is there anyone else out there with halo amps that has a problem with hissing speakers? Any other def tech owners out there with halo equip with this problem? I'm a little bummed out because I was thinking of purchasing an a52 later on for a 7.1 setup but noticed they have no gain settings on this amp. I don't think I could live with the hiss of this amp at thx reference gain settings.

Any comments/suggestions appreciated!
Kyle

[Kingdaddy]

If the noise is tracking the volume level then you have a problem with cabling or dirty power which the PS in the amp should be able to filter. Possibly a bad amp or other gear in the chain. What Pre-Amp are you using to drive the amp?

[kschaan]

right now I'm using my yamaha receiver as a preamp. It has preouts for connecting an external amp. Is it possible that it's the receiver that's causing the hiss? When I had the speakers connected to just the receiver I didn't have any problem with hiss.

[Kingdaddy]

Sounds like the gain output of the Yamaha is too low or the cabling between the two is picking up noise from another source like power wires. Also try lifting the ground switch on the back of the Halo amp and see if that will do anything.

[kschaan]

Thanks for the tips. I already tried lifting the ground and a cheater plug after that and neither made a diffence. I really wanted to use the yamaha for the time being as a prepro until I reseach a little more. Prepros like the c2 are so expensive (at least for me). Plus I'm worried that the video portion will quickly become outdated with hd dvd around the corner.