NOSValves Posted February 18, 2002 Share Posted February 18, 2002 Okay now that I have my Tube Amp all setup and safe to use. I have found I need a component that can regulate the input from various sources. I have a Sony DVP-NS700P DVD player and it has a setting for reducing the Audio output to relieve distortion that I get at higher Volume with my Amp (they call it Audio Attenuation it makes the sound so much sweeter). Now I also have a 5 disc Sony 315 and it doesn't have this feature. Is there a device that can equal such inputs out that I can buy for a reasonable price ?? Thanks Craig This message has been edited by NOS440 on 02-18-2002 at 11:06 AM Quote Link to comment Share on other sites More sharing options...
Ray Garrison Posted February 18, 2002 Share Posted February 18, 2002 What you need is a way to attenuate the volume of the CD player (or other source) that is overloading the input section of the amp. Also, many tube amps have a tremendous amount of gain, so you wind up with sound that is way too loud, particularly with Klipsch speakers, no matter how low you turn the volume control. There are a lot of manufacturers who make passive devices (no power) that have a bunch of inputs on the back, an output, and a volume control. These are usually called "passive attenuators". Adcom makes one, as do many other manufacturers. Do a web search on passive attentuator volume control stereo or some such string and you should get a lot of hits. There are also less expensive options. There is a widget usually marketed as an "L-pad" you can buy from Radio Shack that is basically a volume control. The main difference between the cheapie Radio Shack solution and the (potentially) much more expensive audiophile approved fancy passive attenuator is in the way the volume control interacts with the rest of the electronics in your system. The cheap L-pad type device will typically have an impedence that ranges all over the map depending upon where you have the volume control pointing. This varying impedence can interact with the signal you're putting into it, causing the sound to change in character as you adjust the volume louder or softer. That is, you might find that at loud settings, the sound is pretty good, but when you turn down the volume, because of the way the volume control interacts with the CD player's output, the sound starts to become kind of "hollow" - the midrange level drops more rapidly than the bass or treble. Or vice-versa - the bass and treble could start to roll off very rapidly at low volume settings. The more expensive devices are designed to (at least try and) present a more consistant load to the upstream component, so they affect the sound less as you raise and lower the volume. My that was a long winded complex answer to a simple question... ------------------ Music is art Audio is engineering Ray's Music System Quote Link to comment Share on other sites More sharing options...
chuckears Posted February 18, 2002 Share Posted February 18, 2002 Gosh, where I come from, they call it a "preamp" -short for preamplifier... Quote Link to comment Share on other sites More sharing options...
WMcD Posted February 18, 2002 Share Posted February 18, 2002 If I may disagree with Ray on one point. L-pads are used for speaker level signals; and more importantly, for impedances similar to speakers, i.e. in the 8 ohm range. The input will be around 8 ohms. On the other hand, the impedances of a line level output are several orders of magnitude higher. Using an L-Pad is going to create too high a load. You may find schematics for passive pre-amps (and yes, they do not amplify). It may turn out that they use a 27 or so kilo-ohm potentiometer. From this you could home brew a passive attentuator. Let me suggest you also look on the board for the Klipsch mixer for center channel output. This is a start on a passive attenuator, assuming you want to home brew. Gil Quote Link to comment Share on other sites More sharing options...
Allan Songer Posted February 19, 2002 Share Posted February 19, 2002 I love the flexibility of my C-22! That's why I don't think I'll ever be able to let it go--even though I could sell it for 10 times what I paid for it. Plus it has a KILLER phono section as well as all those controls--AND a mono switch. I paid about $250 for mine oh those many years ago--don't think I could do better for $5,000 for a line and phono stage today if I had to buy "new." Quote Link to comment Share on other sites More sharing options...
NOSValves Posted February 19, 2002 Author Share Posted February 19, 2002 Allan did you get your snail mail ?? Oh and my email addy changed to craigostby@comcast.net . Quote Link to comment Share on other sites More sharing options...
NOSValves Posted February 19, 2002 Author Share Posted February 19, 2002 Mdeneen I like your Idea's. I might have to give you another jingle this weekend and we will discuss the details on the phone. Quote Link to comment Share on other sites More sharing options...
Allan Songer Posted February 20, 2002 Share Posted February 20, 2002 Got the snail mail! Hope your Ameperex are doing fine! Allan Quote Link to comment Share on other sites More sharing options...
NOSValves Posted February 20, 2002 Author Share Posted February 20, 2002 Allan Amperexs are doing awesome. They sound real rich. Mark Theoption that sounded interesting was the RCA cable mod with the dropping resister Quote Link to comment Share on other sites More sharing options...
NOSValves Posted February 22, 2002 Author Share Posted February 22, 2002 Mdeneen Once again great intsructions and the drawing was great thanks. I'll do it this weekend and let everyone know how it works out. Thanks again Craig Quote Link to comment Share on other sites More sharing options...
SOUNDJUNKIE Posted February 22, 2002 Share Posted February 22, 2002 What you need is to set up an r/2r ladder network!!! look that one up. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted February 23, 2002 Author Share Posted February 23, 2002 Well that may work. But I already fixed it thanks to Mdeneen !!!!! It cost me a whopping 69 cents for 4- 22K resisters that I soldered the RCA line between the CD Deck and the Amp and it sounds great no more high volume distortion. You should see the drawing he emailed me to show me how to do it a child could of followed the instructions. He is the man. This message has been edited by NOS440 on 02-24-2002 at 02:01 PM Quote Link to comment Share on other sites More sharing options...
NOSValves Posted February 24, 2002 Author Share Posted February 24, 2002 Update.... After being alone here last night. I slapped 5 discs in the Sony CDP-315 and played music for 3 hours at near full volume. I find that now my $40 Ebay special CD player sounds leaps and bounds above my Sony DVP-NS700P DVD player. Can't believe what a 69 cent mod can do LOL !!!!! Thanks Again Mdeneen Quote Link to comment Share on other sites More sharing options...
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