MichaelShaffer Posted October 3, 2005 Share Posted October 3, 2005 Somebody has a QSC USA900 amplifier (900 watts) for $150. Is that a good deal? How good/bad is QSC compared to Rotel, Creek, etc? Quote Link to comment Share on other sites More sharing options...
Bill H. Posted October 3, 2005 Share Posted October 3, 2005 Michael, form member Min-Male42 (Russ), has posted about these in the Past. He loves them......... Also found this link on pricing........http://www.prepal.com/data/QSC.htm Quote Link to comment Share on other sites More sharing options...
MichaelShaffer Posted October 3, 2005 Author Share Posted October 3, 2005 Cool, if he hasn't sold them yet I'll get them. Anything is better than my Sharp mini component system lol. Quote Link to comment Share on other sites More sharing options...
Bill H. Posted October 3, 2005 Share Posted October 3, 2005 Michael, Looking at the Pictures, I noticed that the speaker connections- (the red ones- look like maybe there was a heat problem. They look like Maybe they were burnt? Might just be the camera , but worth checking out.............FWIW. Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted October 3, 2005 Share Posted October 3, 2005 that has the look of a Cheap ,Imported amp ..... is that why it's called the USA serires ....???.....[:S] Quote Link to comment Share on other sites More sharing options...
Marvel Posted October 4, 2005 Share Posted October 4, 2005 It is an older discontinued model. he newer ones would be well worth the price difference. Like the PLX series that Dean has. Or this model for $300: http://www.zzounds.com/item--QSCRMX850 Bruce Quote Link to comment Share on other sites More sharing options...
MichaelShaffer Posted October 4, 2005 Author Share Posted October 4, 2005 Too late... I just returned from getting the amp. What a waste of time, it's very powerful but the speakers make humming noise even with the gain turned down. Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted October 4, 2005 Share Posted October 4, 2005 your running unbalanced, right ....?? check your input wiring Quote Link to comment Share on other sites More sharing options...
Marvel Posted October 4, 2005 Share Posted October 4, 2005 Michael, Get the manual for this amp: http://www.qscaudio.com/pdfs/usausr.pdf Make sure the connections and settings are all correct. Make sure you are not running in parallel, and try turning off the limiters for both channel 1 and channel 2 (set by the DIP switches). Try setting the gain on the back of the amp to where they point straight up (6 db point). See if this makes a difference. Make sure you don't have it set to bridged mono as well. As a heads up, Sam Ash has the Samson Servo 170 and Servo 260 amps on closeout right now. No fans and a reasonable amount of power (especially for Klipsch speakers). $129 and $149 respectively. The bigger one is 90 wpc into 8 ohms. These are similar to my Alesis RA-100. Bruce Quote Link to comment Share on other sites More sharing options...
MichaelShaffer Posted October 4, 2005 Author Share Posted October 4, 2005 I set all the jumpers to off and the noise persists. It's not really a hum but a snow noise. It does it with the preamplifier disconnected so I don't think it's that. I was also wondering, what's that middle post for where the inputs connect, could that be the cause of the snow noise? Am I supposed to have a ground connected? Quote Link to comment Share on other sites More sharing options...
MichaelShaffer Posted October 5, 2005 Author Share Posted October 5, 2005 your running unbalanced, right ....?? check your input wiring What do you mean unbalanced? Quote Link to comment Share on other sites More sharing options...
Duke Spinner Posted October 6, 2005 Share Posted October 6, 2005 Balanced = +,-, shield unbalanced = +,shield, or gound you got UNSHIELDED wire on yer input ...!!! no wonder it hisse..............[8-)] Quote Link to comment Share on other sites More sharing options...
Marvel Posted October 6, 2005 Share Posted October 6, 2005 Duke, I didn't even notice the wiring. Good eyes! Quote Link to comment Share on other sites More sharing options...
dragonfyr Posted October 6, 2005 Share Posted October 6, 2005 Balanced = +,-, shield unbalanced = +,shield, or gound you got UNSHIELDED wire on yer input ...!!! no wonder it hisse..............[8-)] Duke, you take all the fun out of this!!! I was wondering how so many seemed to simply get past the conversion from unbalanced pre-outs to balanced amp inputs without so much as a mention![] And the 1/4 in plugs that are also compatible for the amp-inputs are TRS (tip-ring-shield) plugs! ...Not simply generic phono plugs! Quote Link to comment Share on other sites More sharing options...
MichaelShaffer Posted October 6, 2005 Author Share Posted October 6, 2005 Time to fork out more money for a preamp I guess, sigh.. I just want to sit down and enjoy the speakers. Quote Link to comment Share on other sites More sharing options...
Marvel Posted October 6, 2005 Share Posted October 6, 2005 If you use the 1/4 inch jack (in the combo connector) you can use an unbalanced tip/sleeve connection and run unbalanced. This probably connects the - to ground. They don't explicitly say so, but you can probably do the same on the barrier input strip. Connect your shield to the ground terminal and the plus to your center conductor. You may need to connect the ground to the - (minus) connector as well. Quote Link to comment Share on other sites More sharing options...
MichaelShaffer Posted October 6, 2005 Author Share Posted October 6, 2005 That's ok, I'll just wait and get a integrated amp or something. I'd probably mess it up and fry something.. Quote Link to comment Share on other sites More sharing options...
dragonfyr Posted October 6, 2005 Share Posted October 6, 2005 Time to fork out more money for a preamp I guess, sigh.. I just want to sit down and enjoy the speakers. Take it easy![]Attached is a paper that will tell you more then you wanted to know, so just use the first example! I will also post it under the Technical Forum with a more easily 'searchable' title for reference. (How's that for an awkward mismatch of adjectives and adverbs![]) bal_to_unbal.pdf Quote Link to comment Share on other sites More sharing options...
Marvel Posted October 6, 2005 Share Posted October 6, 2005 The 1/4 inch combo connectors allow the use of unbalanced 1/4" as well as balanced. Go get some cheap Radio Shack rca to 1/4" adapters. Then you can use your regular rca cables. 10k unbalanced input impedance and 20k balanced according to their manual. Quote Link to comment Share on other sites More sharing options...
MichaelShaffer Posted October 6, 2005 Author Share Posted October 6, 2005 I'm still not sure if it's the balanced issue or if it's because of the burned speaker post.. it seems worse in that channel. Plus there was this huge spark inside the amp. So now I don't even want to connect it to the speakers. I just want to get rid of it. Not to mention it smells like cigarette smoke when I have it on. I think I'm going to just get a Rotel or HK etc.. Tired of this no name brand amp.. Quote Link to comment Share on other sites More sharing options...
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