KungFuNat Posted September 21, 2004 Share Posted September 21, 2004 so after almost a year of lurking around here, i finally put a respectable heritage system together today. this is my first "true" hi-fi system ive ever owned, and i am indeed loving it. BUT, i have a question. im running a NAD cd-player into an older rotel dolby pro logic pre-pro into a hafler DH220. now from what i understand this amp is a bit of overkill for such a highly sensitive pair of speakers. yet i find myself putting the volume on the rotel way past 12 o'clock to get any sort of respectable volume.. anything under 12 o'clock and its maybe 40db im guessing, not much louder than normal speaking volume. at 100% its getting loud, but its still not that loud. hell my promedia ultra system on my computer gets louder at full volume. is there something wrong here? or am i going deaf. is it possible the rotel isnt providing enough juice to drive the hafler? the rotel is a rsp-960ax made in the late '90s i believe. Please help!! Quote Link to comment Share on other sites More sharing options...
Malcolm Posted September 21, 2004 Share Posted September 21, 2004 If your hearing hasn't already been compromised, you shouldn't be able to stay in an average size living room with two Heresys driven at full power. But if you equate loud with bass, you may be disappointed. They are 3 dB down by about 65 Hz and falling quickly. If you want bass, you need a good subwoofer. Quote Link to comment Share on other sites More sharing options...
D-MAN Posted September 21, 2004 Share Posted September 21, 2004 Is that Rotel a 6-channel? If so, you need to ensure that you are set for STEREO operation only with NO MODES, no dolby, etc. RAW STEREO or DIRECT operation. Also ensure that the outputs to the amp are on MAIN connects, set to LARGE speakers. DM Quote Link to comment Share on other sites More sharing options...
sheltie dave Posted September 21, 2004 Share Posted September 21, 2004 Nat, it may not be correct to equate 12 noon on the volume pot to exactly 50% of total amp volume. Plus the amp may not be functioning as it did on the day you purchased it. Finally, drive me out of the room volume may better be equated with there is so much distortion, it is too loud! turn it down! , rather than clean sound. Normally, you can't hear air raid sirens, firetrucks, and lightening when you are cranking Heresys with 50 to 80 good clean watts. Quote Link to comment Share on other sites More sharing options...
KungFuNat Posted September 21, 2004 Author Share Posted September 21, 2004 the rotel is fairly basic, it has a button for stereo only mode. i dont think it has settings for small/large speakers. i was just figuring that at a full 110wpc i would be rattling the windows. right now it just doesnt seem im getting full juice out of my amp. as i said before, my prmedia ultra system can be blaring lound, and i dont just mean bass. should i bring my amp in for service? its pretty damn old. would it be uncommon to see an amp loose its output capacity over time? Quote Link to comment Share on other sites More sharing options...
garymd Posted September 21, 2004 Share Posted September 21, 2004 I run my heresy 1s with a fisher X-100 tube integrated amp that is under 10 wpc and at 12:00 it practically drives me out of the room! Something isn't right. Quote Link to comment Share on other sites More sharing options...
KungFuNat Posted September 21, 2004 Author Share Posted September 21, 2004 yea thats what im talking about, i remember my friends setup which was my first exposure to klipsch heresys. if we put the volume up past 12 o'clock on his POS sony reciever we could go outside in his front yard and play ball while still hearing the music like the speakers were right next to us. im just not getting anywhere near that type of volume. Quote Link to comment Share on other sites More sharing options...
D-MAN Posted September 21, 2004 Share Posted September 21, 2004 Normally, the power amp should go to 100% somewhere around 2 volts input (varies a bit). Here's a rather nasty but sure-fire test. Plug the cd directly to the amplifier inputs with a cd that is rather "tame". This will probably force the amp to go to 100%. Use ear protection as you will have no volume control whatsoever and it will be the equivalent of turning up the volume all the way. That will ensure that the amp is functional at 2+ volts input. If it is anything less than WAY TOO DANG LOUD, then the amp is the problem. If it seems ok, then the preamp is the problem. The only other remaining possibility is that the cd player is bad. Good luck and use ear protection... DM Quote Link to comment Share on other sites More sharing options...
garymd Posted September 21, 2004 Share Posted September 21, 2004 Does your pre have gain controls? Quote Link to comment Share on other sites More sharing options...
KungFuNat Posted September 21, 2004 Author Share Posted September 21, 2004 gain controls? not sure what that is... there is only a power switch, a single 2-channel input and the 2-channel binding posts. Quote Link to comment Share on other sites More sharing options...
garymd Posted September 21, 2004 Share Posted September 21, 2004 Many preamps (including my blueberry) have gain or volume controls for each channel. I guess yours doesn't. They can be very small knobs on the back of the unit or inside the cabinet like on the Mac MX110 I used to have. Quote Link to comment Share on other sites More sharing options...
mike stehr Posted September 21, 2004 Share Posted September 21, 2004 Maybe the Rotel pre isn't pushing enough gain to the Hafler amp. Line output(pre)to amp input impedance mismatch? Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted September 21, 2004 Share Posted September 21, 2004 Had to throw a "Mr. Obvious" line out. Have you checked speaker phase? Carl Quote Link to comment Share on other sites More sharing options...
Deang Posted September 21, 2004 Share Posted September 21, 2004 I think Mike has it. What is the input impedance of the preamp, and the output impedance of the amp? Quote Link to comment Share on other sites More sharing options...
76scalas Posted September 21, 2004 Share Posted September 21, 2004 My Hafler 220 doesn't even get started before I have to leave the room when it's driving my Heresy's! I say your preamp is the problem. Quote Link to comment Share on other sites More sharing options...
heresy2guy Posted September 21, 2004 Share Posted September 21, 2004 There must be a problem somewhere in your system. I've got my Heresy IIs mated to an HK 430 in a 25 x 15 room and at an indicated 12 noon on the volume pot, I can't stay in the room it's so LOUD. And that's with only 25 watts, mind you. Quote Link to comment Share on other sites More sharing options...
KungFuNat Posted September 21, 2004 Author Share Posted September 21, 2004 ok, it sayes the hafler dh-220 input impedance is 47,000 ohms and its input sensitivity is 1.55v for 115w at 8 ohms. you can read the specs yourself here: http://www.hafler.com/techsupport/pdf/DH-220_amp_man.pdf rotels manual is a little more confusing, im not sure if this is what im looking for but: sensitivity 1khz output 1v, stereo - 430mv. it doesnt say anything about output impedance. check out the manual yourselves: http://www.rotel.com/support/pdfs/manuals/rsp960.pdf im gonna try directly hooking up my NAD to the hafler and see how it goes. this is new stuff to me fellas, i appreciate everyones help. Quote Link to comment Share on other sites More sharing options...
dbflash Posted September 21, 2004 Share Posted September 21, 2004 Does you CD player have any kind of volume level control? On the back of the CD player it should have line out. One end of your IC's should plug into that and the other end should go into CD line in. Try using another input like maybe tape in. I am using a Parasound which is 205W, and I can't turn the pre past 10 oclock with out blowing me out of the room or fearing that I will blow my speakers. Danny Quote Link to comment Share on other sites More sharing options...
michael hurd Posted September 21, 2004 Share Posted September 21, 2004 Sounds like the preamp is not producing a large enough voltage to properly drive the input stage of the amplifier. Quote Link to comment Share on other sites More sharing options...
KungFuNat Posted September 22, 2004 Author Share Posted September 22, 2004 no volume control on the cd player, grr. Quote Link to comment Share on other sites More sharing options...
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