rmlowz Posted July 24, 2007 Share Posted July 24, 2007 Hello, I got all three La Scalas running up front it sounds AMAZING!. One problem that I can not deal with is I can here hiss at my seating position (11 Feet) when nothing is playing. Will this harm the speakers? I am now looking for a quieter amp at least for the fronts. I have alway liked the John Curl Design Halo Amps. I have the A 51, A 52 and A23 with a Arcam AV9. They are just to loud for me. It is the amps that are the problem not the AV9. I want to stay with solid state for the theater. I already have a tube amp for 2 channel listening. What is everybody using with their Heritage set up. I am almost thinking since as you all know that very little power is needed to go back with a reciever like a Arcam AVR 350. I have heard this with Heritage and it is dead silent. What do my forum friends think? rmlowz Quote Link to comment Share on other sites More sharing options...
Guest " " Posted July 24, 2007 Share Posted July 24, 2007 I'm surprised to hear about your HISS problem. I have used various models of both old and new Heritage products with both SS and Tube gear and have not come across this. Good luck in resolving. Quote Link to comment Share on other sites More sharing options...
jacksonbart Posted July 24, 2007 Share Posted July 24, 2007 I don't think its your speakers. They are prone to reveal "hiss" that other speakers, but doubt they cause it. Perhaps your getting outside interference, or your source is playing a roll. But I agree your amp is the likely cause. Quote Link to comment Share on other sites More sharing options...
Frzninvt Posted July 24, 2007 Share Posted July 24, 2007 Nope, I am betting it's not the amps it is the DSP's in the pre/pro and welcome to the world of high sensitivity. Easy way to prove it is set the volume control to "Off" or "Infinity" and see if the hiss disappears. Or turn everything off and disconnect the RCA/XLR plugs feeding the amps from the pre/pro, turn the system on and see if the noise is present without signal from the pre/pro. I get some hiss with my NAD T163 and I have tried a myriad of pre/pro's so good luck with that. I have tried many things and none worked or lessened it so I have learned to live with it, sometimes it annoy's me but most times there is always ambient noise in the living room area and I do not notice it. I have thought about dumping all the Klipsch Heritage and going with all old school a/d/s instead like the L910's, L980's, and some L880-II's instead. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted July 24, 2007 Share Posted July 24, 2007 " set the volume control to "Off" or "Infinity" and see if the hiss disappears. Or turn everything off and disconnect the RCA/XLR plugs feeding the amps from the pre/pro, turn the system on and see if the noise is present without signal from the pre/pro. " that would help zero in on the root cause "I have tried many things and none worked or lessened it " This sounds like a challenge. If you have spare amp power...I know of a few noise floor tricks that may surprise you. Quote Link to comment Share on other sites More sharing options...
Frzninvt Posted July 24, 2007 Share Posted July 24, 2007 I had a little less noise when I ran a rare pair of DBX BX1 Reference Configurable (2,3,4 channel) Amplifiers running in 4 channel mode. They were rated at 100W per channel in 4 channel mode I had some hiss but really had to get up near the tweeters to hear it. I wanted a single amp to replace the DBX duo but wanted something close in performance and build quality and after trying the NAD T973, B&K 200.7, and a couple of others I decided on the ginormous Sherbourn 7/2100A I thought the extra 100W would be beneficial even though not necessary. From a sonic performance standpoint it was close the the DBX BX1 duo but lacked some of the finite detail. I think the extra power might be contributing to the noise to some extent. It was worse when I was using Belle Klipsch in the rear with the Klipschorn's and lessened when I went to the Cornwalls. The channel levels are all at "0" having them set lower does not reduce the ambient noise floor. I tried a few pre/pro's before settling on the NAD and it's sonic and movie performance is what keeps it in the rack for now. Thought about trying the B&K Ref 50 S2, I had the first version and did not like the clicking relay's and buried menus that were difficult to set. The Sherbourn PT-7010A is based on the Carver Cinema Grand IV and I have heard of too many issues with them like sub out levels, etc. I stayed away from using the Sherbourn unit. If I back the volume control to infinity, the hiss goes away so I know it is coming from the pre-pro, it is just having five speakers in the room with 104db @1w efficiency in the same room it is to be expected. I even used a pair of McIntosh MC-30's to run the mains for a short time, hardly a difference from the DBX BX1 amps and not worth all the maintainance and constant fiddling that accompanies tube amplifiers. That said when a movie is on and cranking or you have some music going at reasonable levels I forget all about it. I will just live with it until I can find a quiet pre/pro which I don't think is possible because of the DSP's. Quote Link to comment Share on other sites More sharing options...
Saturn5 Posted July 24, 2007 Share Posted July 24, 2007 This sounds like a challenge. If you have spare amp power...I know of a few noise floor tricks that may surprise you. School me, my friend. [8-|] Quote Link to comment Share on other sites More sharing options...
Guest " " Posted July 24, 2007 Share Posted July 24, 2007 "School me, my friend. " There a few devices like the zero autoformer (atlas AF-140, crown CT-170, etc) that allows fine tuning of the impedance your amplifier will see. Increasing the impedance using one of these devices will improve dampening factor, while lowering the noise floor. The cost penalty is an increase in ouput power required from your amp. http://www.enjoythemusic.com/magazine/equipment/0603/midmonth/zeroautoformer.htm So where should you place one? There are different types. Some such as the T2-A install before the mid driver or mid driver+tweeter. Others like the zero device, attach in between the amp and speakers. There are smaller versions that get installed line level devices, pre-amps and amplifier inpuuts which are often refered to as passive pre-amps. Quote Link to comment Share on other sites More sharing options...
Frzninvt Posted July 24, 2007 Share Posted July 24, 2007 I suppose running two four-channel noise gates between the pre/pro outputs and power amplifier would eliminate the problem. The gate would shut when no signal was present and eliminate any noise. I know that Harrison Labs made 4-channel noise gates for automotive use (12V) I wonder if there are pro gear versions of noise gates with adjustable thresholds that could be used to quell the hiss/noise when no signal was present. DBX made an SNR-1 Single Ended Noise Reduction Unit (remove up to 40db background noise/hiss) but I would need 4 of them to do the job. This is what the DBX BX1's look like that I had a pair of. I tried to upload a .pdf file of the DBX SNR-1 User Manual but kept getting "Ooops something is wrong" error. Quote Link to comment Share on other sites More sharing options...
Frzninvt Posted July 24, 2007 Share Posted July 24, 2007 This is Sherbourn 7/2100A that I have now. Maybe I just need to have a little less power but I love headroom and dynamics. The Parasound amps that Rmlowz has are top notch amplifiers and the pre/pro is top notch and he is getting noise so I guess I don't feel so bad about it now. Quote Link to comment Share on other sites More sharing options...
rmlowz Posted July 24, 2007 Author Share Posted July 24, 2007 Hello , Your Sherbourn amp gets a lot of good reviews and feedback, a lot of of people on AVS have them and love them. I might need to get one and try it out one day. I had a good conversation with the owner of Sherbourn Ron Fone one day. I think what I am going to do is get a Arcam P90 with the additional 3 channel amp module 3 x 90 watts. I have heard the Arcam amps are quite. I have a lot invested in the Halo amps.I will hold on to them for the Ultra II system for my retirement home. I wanted to get one of the FMJ amps from Arcam but all of the FMJ stuff went up 10% today something to do with the overseas dollar. I cant justify the cost maybe it has something to do with the hobby fund getting very low. It is definatley the Halo amps you can turn off the AV9 completely and still here the hiss. Just another day in the Klipsch upgrade path. Thanks for everyones advise and opinion. rmlowz Quote Link to comment Share on other sites More sharing options...
Rudy81 Posted July 26, 2007 Share Posted July 26, 2007 What type of connection are you using between your processor and the amps? I use the HALO line with my HT system and the hiss is only audible if I stick my ear next to the horns. From my seating position, there is no perceptable hiss. This is with my connections being RCA. If I use the XLR connections, I can hear the hiss at the seating position. If you are using the XLR connections, and they are not TRUE balanced connections, you will notice the hiss more due to the 6 dB gain in the XLR connections. Quote Link to comment Share on other sites More sharing options...
rmlowz Posted July 26, 2007 Author Share Posted July 26, 2007 Hello, I am using the RCA connections. The AV9 does not have balanced connections. You are right, I have had more hiss using balanced on other systems I have had. rmlowz Quote Link to comment Share on other sites More sharing options...
Rudy81 Posted July 26, 2007 Share Posted July 26, 2007 I am going to have to guess that either your pre/pro is at fault, or the cables are picking up noise. I hope you get it worked out. Quote Link to comment Share on other sites More sharing options...
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