ntn1

Thanks everyone for responding. It's really a white noise hiss, and not a hum. The level is relatively low enough that it's not noticeable while playing audio, but I prefer to have less hiss than it is now. My all digital pre/pro does not have an analog signal processing section, and does not have analog inputs other than the feedthrough bypass. All the signal processing (volume, filtering, equalizing, etc.) is done in the digital domain. The DACs convert the signal to analog before sending it out to the power amp. I can not test the analog inputs as people have suggested. Thanks to formica & micheal hurd's suggestion, I now realize that my pre/pro does have a "noise gate", and it's the DACs that might causes the hiss. I can hear the relays clicking softly as it detects input signal, probably activating and routing the signal path to the various processing circuitry. At this point, I think the pre/pro is at least 50% of the problem. To the subject of balanced and unbalanced components as Rudy81 has mentioned, I feel this could reduce the hiss if done right. All of my AV components have two-prong AC plugs, so they are probably unbalanced. There is nothing I can do here. Rudy81, What exactly do you mean by the balanced and unbalanced connections? I use standard audio patch cables to connect my pre/pro to the power amp (exact same type for all 5 channels), and optical/digital coaxial cables to connect audio sources to the pre/pro. The optical cable is the one that came with my E86 STB. The digital coaxial cable is home made, using Belden 1694A precision 75-Ohm digital video coax, and Canare true 75-Ohm RCA connectors. I strongly believe it's better than the brand-name cables. I must use the optical connection for the STB, and I must use the digital coax for the DVD. There is no other way to get Dolby digital audio. What else can I do? Ray, Yes, when I turn on the DVD w/o a disc in it, I immediately hear the hiss after my pre/pro detects the supposedly-silent (zero bit level?) PCM stream. I can hear a relay click to route the digital input to the default 2-channel PCM decoder. If there is a disc with DD5.1 on it, the relay clicks again to route the signal to the DD5.1 decoder. And of course, hiss is audible when audio is silent. My DVD & STB are located just above the pre/pro. You can see them in the link I provided in my 2nd post in this thread. I'll try your recommendation eventually to see if things improve. I hope to hear more about balanced/unbalanced components, which I am not familiar with, but heard that it could reduce the hiss noise.

lynnm, Thx for the response. Pictures of my equipment can be seen here: http://f2.pg.photos.yahoo.com/ph/nicnguye/lst?.dir=/910+with+DD5.1&.view=t The RW-12 subwoofer is on back order. All of my AV components have two-prong connectors, including the Adcom power amp, and all connected to the same power strip. The Earth ground is already floating. I am reluctant to reverse the polarity because the two-prong-connectors are keyed. The hiss is not from the power amp or the pre/pro. As stated earlier, my power amp and pre/pro combination produces absolutely no noise even at 100% volume level. It's when I turn on the DVD player, or the STB that provides digital audio feed that I start to hear the hiss. If it were analog connections, then the hiss would be understandable with ground loop problem. But mine is all digital: Optical, and digital coaxial connections that produce the hiss. How could this be? Thanks.

My digital audio setup is very simple: Hughes E86 STB and a DVD player connected to an all digital pre/pro (Sony SDP-EP9ES) though optical and digital coax respectively. The pre/pro is then connected to an analog power amp (Adcom 7400), then to the speakers. When the E86 or DVD player is off, the pre/pro and power amp combination produces absolutely no hiss even with volume is up 100% and ears pressed against the speakers. Only when the E86 or the DVD player is powered on, with nothing playing, there is a mild hiss from the speakers. The hiss level changes with the volume level. How could the digital connection (optical, digital coax) produce the hiss? I appreciate any help. Thanks.

Thank you everyone. I have stretched my budget, and just ordered a set of Klipsch speakers for my Sony 34XBR910 HDTV setup: Main: RF-25 x 2 Center: RC-35 x 1 Surround: RS-35 x 2 Sub: RW-12 x 1 I'll drive these with Sony SDP-EP9ES DD5.1 pre/pro, and Adcom 7400 5x100W amp. I'll post picture after I have everything in place.

Doug, Thanks for replying. I have the Adcom 7400 5x100W amp. I realize that the average power level that we listen to is around 3-10W, while transients could be hundreds of Watts. Technically, the Adcom could blow the RS-25 if the volume is set high enough by accident. I wanted to get the RS-25 due to my limit budget at this time, but I think I'll have to wait and save a little more for the RS-35. I wish the RS-25 could handle 100W just to be safe. NTN

Hi, I appreciate much if Klipsch or someone here can explain the following: 1/ With 6.5" woofer, how could the RS-35 not go as low as the RS-25 with just a 5.25" woofer? (81Hz for the RS-35 vs. 79Hz for the RS-25). It doesn't make sense. 2/ Why is the continuous power rating of the RS-25 only 75W? It seems very low compared to the rest of the "matching" -15 or -25 system. Thx.

Thank you everyone for replying. Since I plan to mail order these speakers, returning them is a hassle. I think I will get the RC-25 center speaker from my local dealer, and try it out first. Magnetic interference can be tough to solve when you can not move your TV from the problem source. High permeability shielding materials are expensive. If anyone knows how best to add magnetic shield to the speaker, using cheap and readily available materials, please let me know. Thanks.

---------------- On 9/5/2003 2:23:35 PM gcoker wrote: Where do you find a RW-12 for $500.00. The MSRP in $650. ---------------- The RW-12 goes for $429 + shipping ($14 - $38) at: http://brandnamez.com/merchant.ihtml?pid=1204&step=4

I am thinking about getting the RF-15, RC-25, RS-25, RW-10 to start my modest HT. I heard on the AVS forum that the RC-25 is not well shielded. Since I need to place it right on top of my new Sony 34XBR910 HDTV, I am afraid that it may damage my CRT. Does anyone here own the RC-25, and can comment on its magnetic shielding? Thank you.