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Hiss not Hum help

Hi all,

I have been on my "audiophile"  journey for several years and my main goal is to reach great instrumental separation and clear voice with a wide soundstage.

I mixed and matched many brands such as Anthem, Onkyo, Parasound, Emotiva, Furman, APC, Audioquest, Kimber Cable, Oppo, Ifi, and even DIY, and in general, liked the sound of the latest system, however, there is a hiss coming out of any tweeter, and overall for music is fine since I am 10 feet away from my front towers but If I turn on the Home theater the aggregation of all speaker makes the hiss unbearable.

My attempts to solve the "problem"  include replacing receivers and preamps like switching from Onkyo to Oppo network streamer and recently to Anthem AVM60, and also from RCA to XLR cables, which I used basic cheap RCA, to AudioQuest Red, Acoustic Research Master series, and currently Mogami Gold, cables and cable type made no difference.

On the power line, I started with a regular cyber power AC filter, moved to an APC H15 AC filter, then a Furman Elite PF15, and also tried an Emotiva CMX2 and an Ifi AC purifier, all of this made little to no difference.

Does anyone here experience similar hissing, and has any budget suggestions to attempt to solve this issue?

thanks for everyone's help.
badgod86
oldhvymec
5,101 posts
 
Doesn't  the Parasound have a gain option. Turn it down.

Disconnect EVERYTHING except the preamp, amp and one source.

If you have tone control put them all in the flat position.

A loudness option turn it off.

When I say unplug, I mean from the Power supply and the RCA/XLR/EVERYTHING.. Cable boxes/routers and Laptops PS are the worst..

Go to a single outlet.

If your speakers have LPads make sure they are in the 12 oclock or less position.. Turn the LPads CCW to decrease...

Cable Art is something EVERY audiophiler need to learn. You CANNOT plug and drop cable runs... They have to be separated and cross at 90 degree (close) NO TOUCHING... Cables are everywhere in my house, 3 or 4 systems.. NO NOISE....BLACK as pitch background.. All behind routing cables correctly.. Cable Art...

Regards
erik_squires
16,056 posts
 
None of your problems are power related, I guarantee it, but good for using Furman! :-)

Turn the volume down on the Parasound amps until the his is gone, and adjust the volume on your AVM 60 accordingly.
badgod86 OP
11 posts
 
I briefly tested today with a noise isolator and a 10db attenuator, and the 10db attenuator worked great, hiss is only audible a few inches from the tweeter, I am going to do additional testing to ensure sound quality was not degraded but I purchased a professional-grade microphone attenuator, it should be at least decent... will update further.
auxinput
2,920 posts
 
The attenuator will basically reduce the entire signal level (which does include the hiss).  The result is that you will have to turn up the volume control higher than normal on your preamp equipment to get the same amount of sound out.  As long as you are able to get enough loudness out of your speakers to make you happy, this is a great solution.
badgod86 OP
11 posts
 
@auxinput, yes I understand the point of attenuators, they attenuate the voltage/amplitude of the entire signal, but I tested this at 0DB and compensated on the preamp by setting the sound to be +10DB, yet it improved and that is why I will do additional testing tonight.

even if it lowers the overall top loudness I never went about -20DB if the sound is decent and hiss is inaudible at 1 foot away at 0DB, I will be happy at most levels.
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