powdermnky007 Posted November 22, 2004 Share Posted November 22, 2004 This started out as a reply to the decware opinions, but grew into a new post. Man those amps are sweet looking craig. Can't afford that yet... Bet they would rock with a blueberry Speaking of the Dec 685 cd player,I just bought one. I have a mapletree ultra 4a preamp. Later this week I will be doing some in depth listening. This being my first tube system, I won't be able to give an accurate response to how good it sounds, because the only system I've ever heard is mine. I read that they do sound better than the stock ah tjube. But if you mod out the ah with upsampler it will win. I wanted the dec unit cause its a 5 disc dvd/mp3 player. It also plays sacds, which is the main reason I prefer it to the ah. If I happen to get a better cd player, I can retire this one to another use. Its very versatile. The cd player is able to be hooked up to a tv, you can turn on different dac voicings sharp or a relaxed option. There is an attenuation feature. Lots of different stuff, fun to play with for sure This is all built into the standard sony cd player. The only problem I had was it was over driving my preamp. The output on it is very loud. apparently I'm the only one who ever had this problem. I shipped it back to him and he checked it out for me. Said nothing was wrong and recommended I get part # 27-4045 at mcminone.com it is a rca line level reducer, I got the 3db one and a 1db one. 3 turned out to be way too much. the 1db was just right and now theres some good sounding tunes coming out! I don't know how good the quailty of those rca reducers are. If anyone knows of an autophile level reducer, let me know Just so I can make sure I'm getting the best sound. I wish someone who had heard lots of systems, could come listen to mine and tell me how it stacked up. If anyone is ever around sulphur/lake charles, la. You'll have to drop by We need a get together in the south! Quote Link to comment Share on other sites More sharing options...
Daddy Dee Posted November 22, 2004 Share Posted November 22, 2004 Thanks for your take on the Decware 685. I've been terribly curious about that piece of gear. I listen to the Ah! w/upsampler and am quite pleased with it, however the versatility of the 685 playing SACD's and DVD's is most attractive. It is also priced as a bang for buck champ. The overdriving issue is odd, and I'm not familiar with the possible solutions for attenuating that signal without degradation. Yes, we do need a get together in the south. I'm hoping to put together another one in Arkansas for sometime in the spring of 2005. Hope that would be close enough for you to bring the 685! Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted November 22, 2004 Share Posted November 22, 2004 Hi! Your problem may actually be more associted with your preamp than the CD player. The couple-few volts output of most CD players should really work well with many preamps, but there are some other things to consider. Among these are interstage impedance relationships of the components you have. Both preamp and amp (if it's a tube amp) probably have fairly high input impedances, which can make them very sensitive to not only music signals, but noise pickup, as well. In other words, it may only take a very minimal turn of the volume control for really loud volume levels. Sometimes this can be fixed by series resistance on the input (which is what those inline attenuators do), and/or reducing the value of the volume control. If you have a variable output on your CD player and the remote has a volume control, you might just try running directly into the amplifier, thereby bypassing the preamp altogether. This is just as an experiment to see what happens without the preamp. If you find that the preamps is what is causing the overloading, there are some things that can be done to pad done the sensitivity. Quote Link to comment Share on other sites More sharing options...
Marvel Posted November 22, 2004 Share Posted November 22, 2004 Erik, Did I send you the little program I have that calculates pad values? It will do balanced (H pad) or unbalanced (T pad). You specify the input impedance, output impedance and amount of reduction in db. It give your the value of resistors to use. I have used it quite successfully to match equipment. It's pretty cool. Since it is a real pad, there are three resistors for each channel (unbalanced), as it makes a regular voltage divider. Marvel Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted November 22, 2004 Share Posted November 22, 2004 Hey, Marvel: I have recently discovered calculators for series and parallel capacitance and resistance, but I have not seen anything like this that can calculate values for desired reduction in gain. I've used T-pads on amps before, and they can work wonderfully well, but it often took some trial error and guessing to get things sounding right. Thank you! Erik Quote Link to comment Share on other sites More sharing options...
powdermnky007 Posted November 23, 2004 Author Share Posted November 23, 2004 Sure, whenever you have the get together I'll bring the DEC up there I tried everything with the volume control, it even distorts when you can barely hear it over the speakers. I sent emails to both the preamp designer and steve at decware. I sent steve all the preamp specs and he said the impedences were all okay. The preamp guy said it wouldn't damage the preamp, but he would rather see 2.0v than 3.5v at it. on Steves outputs there is no volume control, it's balls to the wall all the time =) at 3.5v the cd player is almost putting out a full watt. (at least that is what the preamp manufacturer said) Maybe I should hook the rcas up to my speakers Quote Link to comment Share on other sites More sharing options...
NOSValves Posted November 23, 2004 Share Posted November 23, 2004 ---------------- On 11/23/2004 9:23:02 AM powdermnky007 wrote: on Steves outputs there is no volume control, it's balls to the wall all the time =) at 3.5v the cd player is almost putting out a full watt. (at least that is what the preamp manufacturer said) Maybe I should hook the rcas up to my speakers ---------------- Now that would be a impedance mismatch for sure. I still can't figure out why they set that player up with 3.5V of output. Craig Quote Link to comment Share on other sites More sharing options...
Marvel Posted November 23, 2004 Share Posted November 23, 2004 Erik (or anyone else), You can get the pad calculator at the link below. I won't leave it up forever, but feel free to get it. The site I had gotten it from no longer has it listed. HPad calculator Let me know if it is useful. Marvel Quote Link to comment Share on other sites More sharing options...
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